Dissertationen zum Thema „Electronic device testing“

The Internet of Things (IoT) is a rapidly growing network. As society begins to trust the devices in the IoT with increasingly complex tasks, issues regarding the security of these devices are of high priority. An example of an IoT-device in which failure of security could be fatal, is the Telia Sense. Telia Sense is an OBD-II dongle which together with a mobile application connects a car to a smartphone.In this paper, the discoveries that was made during security testing of Telia Sense will be discussed. The system was investigated through a black box perspective. Primarily, a model of the system was produced. Threats were then identified, ranked and tested accordingly.No major vulnerabilities were found. The results all indicated that Telia Sense is a well secured system. The main reasons to this is the fact that the device has very limited functionality and its communications are bounded. Even though no major vulnerabilities were found, this paper can still be used as a guide for future testing of security in IoT devices.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaf 35).
Conducting polymers have the potential to serve the technical and commercial communities with novel actuators, sensors, and biomimetic devices. The conjugated structures of these polymers and the addition of dopants enable conduction. [1] One current goal in the conducting polymer field is to observe and understand the events by which these polymers carryout their active mechanical functions (contraction and expansion) upon the application of a potential. This thesis presents the design and a prototype of a new device for investigating the relationship between the mechanical and electronic properties of conducting polymers with EPR Spectroscopy. The performance of the testing device was explored with a controlled experiment. The results of this experiment suggest that the response of conducting polymer actuators to mechanical inputs can be examined with EPR Spectroscopy.
by Nicholas R. Powley.
S.B.

The work presented in this dissertation is focused on the fabrication, integration and test of chemoresistive gas sensor devices and systems based on semiconducting nanowires (NWs). The first objective of this dissertation was to grow monocrystalline In2O3 and Ga2O3 NWs via the vapor-liquid-solid mechanism using a chemical vapor deposition furnace and solid precursors. Subsequently devices based on individual NWs were fabricated, contacted on top of microhotplates using Focused Electron Beam Induced Deposition (FEBID), and their gas sensing properties were characterized. The gas sensors based on individual In2O3 NWs present considerable response towards ethanol at 300 ºC, with a response time of about 4 minutes. On the other hand, the gas sensors based on individual Ga2O3 NWs showed high selectivity towards relative humidity at room temperature, with resistance variations up to 90% in times as short as 2 minutes, and with minimal response to other gases (NO2, CO, ethanol and H2). This behavior is completely different from that reported on this material and is a direct consequence of the NW growth method, which gives rise to a carbon shell around the NWs. Furthermore, the sensing behavior ressembles that of carbon-containing materials.. A second objective was to deepen into methodologies to integrate the sensing material in the substrates where the gas sensing devices are fabricated, with the aim of simplifying the integration procedures and increasing the throughput. With this in mind, dielectrophoretic alignment of NWs was the first methodology proposed to fabricate chemoresistors based on arrays of individual WO3 NWs. The maximum gas response of the fabricated arrays of individual NWs was towards 5 ppm of NO2 for the pristine and towards 100 ppm of EtOH for the Pt-functionalized WO3 NWs, respectively. This higher response of the Pt-functionalized WO3 NWs-based gas sensors is related to the surface decoration of these NWs, which increases the amount of oxygen adsorbed species at their surface, allowing EtOH molecules to be more easily adsorbed than on pristine NWs. The second approach proposed for contacting individual SnO2 NWs on top of suspended microhotplates was Electron Beam Lithography (EBL) in combination with lift-off. The method allows fabricating several devices sequentially but without breaking the vacuum of the EBL system and required optimization of the holder for spinning and of the electron dose used to modify the photoresist properties. The gas characterization of these devices showed higher resistance variations than that obtained for the reference fabrication technique, FEBID. This superior behavior can be the result of the better electrical characteristics of the Ti/Pt contacts in front of the FEBID Pt-deposition. This demonstrates the potentiality of this techniques for contacting individual NWs on top of micromembranes. The third objective was, to a certain point, a natural extension of the device integration activity when considering one of the major drawbacks of chemoresistors: their lack of selectivity. For this, SnO2, WO3 and Ge NWs, have been grown on well-defined and pre-specified regions of one single chip, allowing their simultaneous operation. Here, NO2, CO and relative humidity (RH), diluted in dry synthetic air, have been tested. The calibration of each individual sensor has been carried out exposing the whole chip to the individual gases but with only this particular sensor heated and biased, while the others were unheated and unbiased. This has allowed determining the optimal operation conditions for each sensor. Next, at these optimal temperatures, all the sensors have been tested, simultaneously, towards each gas specie alone. Finally, tests of the three sensors, operating simultaneously, towards mixtures of the three gases were performed. The data from all the mentioned measurements have been treated according to the Principal Component Analysis (PCA) methodology and the results demonstrate that the fabricated sensor system can discriminate and quantify the concentration of the three different studied analytes. The three sensors, made of three different materials and operating simultaneously, constitute an electronic nose, which we here call nano electronic nose.
Aquesta tesi doctoral està enfocada al desenvolupament de dispositius i sistemes sensors de gas basats en nanofils semiconductors monocristal·lins. El primer objectiu aconseguit és el creixement de nanofils d’In2O3 i de Ga2O3 utilitzant un forn pel dipòsit químic en fase vapor. Els nanofils fabricats s’han transferit a xips amb micromembranes suspeses amb calefactor i nanofils individuals s’han contactat amb els seus elèctrodes, emprant el dipòsit assistit per feixos d’electrons. Els nanofils d’In2O3 mostren una resposta considerablement selectiva enfront d’etanol a partir dels 200 ºC i els de Ga2O3 són molt selectius a la humitat relativa a temperatura ambient, fruit del mètode de creixement. Un segon objectiu d’aquesta tesi ha estat explorar dos mètodes d’integració de nanofils individuals: la dielectroforesi, per alinear nanofils de WO3, que han mostrat respostes enfront d’etanol i NO2, a 250 ºC, i la litografia per feixos d’electrons, per contactar nanofils de SnO2 sobre microplataformes calefactores suspeses, que han mostrat respostes satisfactòries enfront d’amoníac a 200 ºC. En ambdós casos s’ha demostrat la viabilitat d’aquestes tècniques. L’últim objectiu ha estat la fabricació i caracterització d’un nas electrònic basat en xarxes de nanofils de SnO2, WO3 i Ge integrades en cadascuna en una micromembrana d’un mateix xip. Aquests nanofils s’han fet créixer directament en regions localitzades i predefinides del xip, les micromembranes, integrats directament en ell, evitant la necessitat de transferir-los després de fer-los créixer. Primer s’ha realitzat el calibratge de cada sensor individual enfront de tres gasos individualment, després enfront de tres gasos simultàniament i, finalment, els tres sensors s’han fet funcionar alhora enfront dels tres gasos. Les dades de totes les mesures s’han tractat segons la metodologia d’anàlisi de components principals i els resultats demostren que aquest sistema és capaç de discriminar entre diverses mescles de NO2 i CO diluïts en aire sintètic sota diferents nivells d’humitat relativa. Els tres sensors, formats per els tres materials diferents i funcionant simultàniament, constitueixen un nano nas electrònic.

A key problem faced with the implementation of a multi-terminal direct current (MTDC) grid is fault mitigation. One method extensively researched in mitigating a fault in MTDC is to use protection intelligent electronic devices (IEDs) and fast direct current circuit breakers (DCCBs). The IEDs are able to detect and identify faults with fault algorithms. In this study overhead line MTDC systems are investigated to identify the best algorithm for overhead line (OHL) MTDC fault mitigation and the resulting algorithm is tested on a protection IED. Three models: short line, long line and combined line models are developed with varying DC line lengths on the software PSCAD and are analysed under line to line (L-L) and line to ground (L-G) faults with multiple fault impedance at a variety of fault locations. The voltage derivative algorithm has performed the best in detecting and identifying faults under OHL conditions. However, its performance declines with the increase of length of DC lines of the MTDC. Therefore, transient based algorithms were also tested. They are a better _t for remote faults compared to voltage derivative algorithms. However, they perform poorly for close faults. The critical threshold for fault detection is obtained through the algorithms and are implemented to the IED. A waveform generator will simulate faults and the IED is tested with the critical threshold obtained. The IED performed as expected and produced results similar to the software analysis. The critical threshold obtained through the algorithm was applicable to all DC lines of MTDC grid. Wide adaptation of MTDC is expected and this will increase complexity in the grid network and modelling of it. Therefore, new lines implemented to MTDC grids may have to identify their critical protection threshold with simplified MTDC grid models. Evidence towards the possibility of modelling a point-to-point high voltage direct current (HVDC) system to identify threshold values can be obtained from this study as the results suggest that the maximum derivative values are highest for internal faults rather than external faults.
Ett centralt problem inför implementeringen av ett multiterminalt DCnät (MTDC-nät) är feldetektering och bortkoppling av fel. En metod som har  undersökts mycket för att detektera och bortkoppla ett fel i MTDC-nät är att  använda en skydds-IED (intelligent electronic device) och likströmsbrytare (eng: direct current circuit breakers, DCCBs). En IED kan upptäcka och identifiera fel med hjälp av skyddsalgoritmer. Denna studie syftar till att identifiera den bästa algoritmen för feldetektering i luftledningar i MTDC-nät och den resulterande algoritmen testas på en skydds-IED. Tre linjemodeller: korta, långa och kombinerade implementeras i programvaran PSCAD och simuleras under pol-pol-fel och pol-jord-fel med era felimpedanser på en mängd olika felplatser. Spänningsderivataalgoritmen har fungerat bäst för att upptäcka och identifiera fel i luftledningar. Men dess prestanda minskar med längden hos DC-linjernas för MTDC. Därför testades också transientalgoritmer. De passar bättre för fjärrfel jämfört med algoritmer baserade på spänningsderivata. De fungerar dock dåligt för närliggande fel. Den kritiska tröskeln för feldetektering erhölls genom algoritmerna och implementerades i IEDn. En vågformgenerator simulerade fel och IEDn testades med den kritiska tröskel som erhölls. IEDn fungerade som förväntat och producerade resultat som liknar programvarans analys. Den kritiska tröskeln som erhölls genom algoritmen var giltig för alla DC-linjer i nätet. Bred anpassning av MTDC förväntas och detta kommer att öka komplexiteten i nätverket och dess modellering. Därför kan nya linjer implementerade för MTDC-nät behöva identifiera dess kritiska skyddströskel utan att modellera hela nätet. Denna studie indikerar att det är möjligt att modellera ett punkt-till-punkt HVDC-system för att identifiera tröskelvärden för ett MTDC-nät eftersom resultaten antyder att de maximala derivatavärdena är högst för interna fel snarare än för externa fel.

This thesis describes an embedded data logger project, composed of software part (in C++ language) and hardware part (Raspberry Pi). It is illustrated the whole procedure from the start of the project with requirements to the end with the experimental results and validation phase. The device is able to acquire, in a synchronous way, videos, CAN and Serial logs from the vehicle under test.

This diploma thesis deals with the design and implementation of a computer-controlled device for testing gas boiler control units, especially in the development phase. The reason for creating a test facility is the inadequacy of older test systems and the automation of existing testing. The test device in development consists of individual different cards. Each of the cards inserted into the motherboard performs its function in the system. Each of the cards has a special functionality which simulates the real conditions of the developed product. The basis of most cards is a microcontroller with a Cortex-M core, which communicates with the connected computer using the MODBUS protocol on the RS-485 communication interface. All cards on the bus are connected in parallel and behaves as a SLAVE, while the computer behaves as a MASTER and requests data or sends commands to the cards. The cards represent status switches (switching sensors), resistance and analog temperature sensors, PWM inputs and outputs (for simulation of feedback pumps or flow meters with pulse output). The cards also include a flame simulator, which reliably simulates the electrical properties of the flame and at the same time acts as a fan simulator. The input of the control unit is taken care of by the input card, which is intended for digital detection of the voltage presence in the range of 5 to 230 V DC and AC. Simultaneously, a card for connecting the power supply at zero voltage and disconnecting at zero current is created to supply the tested device with alternating voltage. A schematic diagram was designed or simulated for each card, then the function was verified and on this basis the whole card was created, including the microcontroller firmware. The most suitable solution and function of each card is carefully described and evaluated. All the requirements of the assignment within the work were met and the whole test equipment was manufactured and verified in four versions. In the future, the device is ready for the implementation of an automatic flame simulator and other improvements of individual module cards.

Computing technology has been getting more reliable and cheaper every year for the past several decades. Consequently, IoT devices have now become a part of medical technology. One example of this is a new open-source technology that has emerged for type-1 diabetes patients, which regulates the patients’ blood glucose levels. One component of this open-source system is AndroidAPS, a mobile application that manages and controls the system by communicating with the two other components: a blood glucose sensor and an insulin pump. Another component is Nightscout, a web application for monitoring T1D patients. Together they form the APS ecosystem that automatically i) reads blood glucose values, ii) syncs the data with Nightscout, iii) stores patient information into Nightscout database, iv) calculates optimal treatment plan, and v) regulates pump for the ideal insulin intake. The whole system bears several critical assets to guarantee patient health. In this thesis, the security of a representative APS ecosystem is studied. We found 5 critical vulnerabilities in the ecosystem: 1) an XSS vulnerability in the web application due to ineffective input sanitization which lead to stealing administrator password from browser cache, 2) highly sensitive patient data is open to public by default, 3) the web application login mechanism, where all system data is managed, is weak against password guessing attacks together with 4) insecure GET requests used for authentication, and lastly 5) any type of database hijack does not trigger any alarms for Nightscout. Successful attacks result in malicious values synchronized from Nightscout to tamper correct insulin delivery calculations. Possible attack scenarios, devised from existing vulnerabilities in this work, show how an attacker can physically harm their victims through their internet-connected insulin pump.
Datorteknik har blivit mer pålitlig och billigare varje år under de senaste decennierna. Följaktligen har IoT-enheter nu blivit en del av medicinsk teknik. Ett exempel på detta är en ny öppen källkodsteknik som har utvecklats för typ 1- diabetespatienter, som reglerar patienternas blodsockernivåer. En komponent i detta öppen källkodssystem är AndroidAPS, en mobilapplikation som hanterar och kontrollerar systemet genom att kommunicera med de två andra komponenterna: en blodsockersensor och en insulinpump. En annan komponent är Nightscout, en webbapplikation för övervakning av T1D-patienter. Tillsammans bildar de APSekosystemet som automatiskt i) läser blodsockervärden, ii) synkroniserar data med Nightscout, iii) lagrar patientinformation i Nightscout-databasen, iv) beräknar optimal behandlingsplan och v) reglerar pumpen för perfekt insulinintag. Hela systemet har flera kritiska tillgångar för att garantera patientens hälsa. I denna avhandling studeras säkerheten för ett representativt APS-ekosystem. Vi hittade 5 kritiska sårbarheter i ekosystemet: 1) en XSS-sårbarhet i webbapplikationen på grund av ineffektiv sanering av ingångar som leder till att stjäla administratörslösenord från webbläsarens cache, 2) mycket känsliga patientdata är öppna för allmänheten som standard, 3) webben applikationsinloggningsmekanism, där all systemdata hanteras, är svag mot gissningar av lösenord tillsammans med 4) osäkra GET-förfrågningar som används för autentisering, och slutligen 5) någon typ av databaskapning utlöser inga larm för Nightscout. Framgångsrika attacker resulterar i skadliga värden som synkroniseras från Nightscout för att manipulera korrekta insulinleveransberäkningar. Möjliga attackscenarier, utformade utifrån befintliga sårbarheter i detta arbete, visar hur en angripare fysiskt kan skada sina offer genom sin internetanslutna insulinpump.

Consumer demands are driving the current trend in the microelectronics industry to make electronic products that are miniature, fast, compact, high-density, reliable and low-cost. The use of surface mount devices (SMDs) has helped to decrease the size of electronic packages through the use of solder bump interconnections between the devices and the substrates/printed wiring boards (PWBs). Solder bumps act as not only mechanical, but also electrical interconnections between the device and the substrate/PWB. Common manufacturing defects ¨C such as open, cracked, missing, and misaligned solder bumps ¨C are difficult to detect because solder bumps are hidden between the device and the substrate/PWB after assembly. The reliability of packaged electronic devices in storage and usage is a major concern in the microelectronics industry. Therefore, quality inspection of solder bumps has become a critical process in the microelectronics industry to help ensure product quality and reliability. In this thesis, a methodology for quality evaluation and reliability study of solder bumps in electronic packages has been developed using the non-destructive and non-contact laser ultrasound-interferometric technique, finite element and statistical methods in this research work. This methodology includes the following aspects: 1) inspection pattern ¨C specific inspection patterns are created according to inspection purpose and package formats, 2) laser pulse energy density calibration ¨C specific laser pulse power and excitation laser spot size are selected in terms of package formats, 3) processing and analysis methods, including integrated analytical, finite element and experimental modal analyses approach, advanced signal processing methods and statistical analysis method, 4) approach combining modal analysis and advanced signal processing to improve measurement sensitivity of laser ultrasound-interferometric inspection technique, and 5) calibration curve using energy based simulation method and laser ultrasound inspection technique to predict thermomechanical reliability of solder bumps in electronic packages. Because of the successful completion of the research objectives, the system has been used to evaluate a broad range of solder bump defects in a variety of packaged electronic devices. The development of this system will help tremendously to improve the quality and reliability of electronic packages.

Internet of Things (IoT) devices are becoming more ubiquitous than ever before, and while security is not that important for every type of device, it is crucial for some. In this thesis, a widely available Bluetooth smart lock is examined through the lens of security. By using well-known attack methods, an attempt is made to exploit potential vulnerabilities in the system.The researched lock was found to have design flaws that could be considered low-impact vulnerabilities, but using the system without these flaws in mind could lead to harmful outcomes for the lock owner.Except for the design flaws, no real security problems were discovered, but the methods used in this thesis should be applicable for further IoT security research.
IoT-apparater blir allt mer vanliga i samhället. Det är inte ett krav för alla typer av apparater att ha stark säkerhet, men för vissa är det helt avgörande. I denna avhandling undersöks ett allmänt tillgängligt Bluetooth-smartlås utifrån ett säkerhetsperspektiv. Genom att använda välkända angreppsmetoder görs det ett försök att utnyttja potentiella sårbarheter i systemet.Låset visade sig ha designfel som skulle kunna betraktas som sårbarheter med låg hotnivå, men att använda systemet utan dessa designfel i åtanke skulle kunna leda till farliga påföljder för låsägaren.Förutom designfelen upptäcktes inga riktiga säkerhetsproblem, men metoderna som används i denna avhandling bör vara tillämpliga för ytterligare säkerhetsforskning inom IoT.

Abstract Electronic industry is developing advanced and versatile products to satisfy customers' needs. It is also creating new needs, which expand the market further. This highly competitive field forces companies to produce continuously better, and hence more complex, products at an increasingly fast rate. This is particularly true of the mobile phone industry, which pursues higher volumes and penetration rates throughout the world. Very high volumes and extreme complexity require intensive research and a commitment to high product quality. Mobile phone manufacturers must commit themselves to strict quality standards and programs, which ultimately enable high customer satisfaction. Both quality assessment and product management generally need a method of feedback to be able to react to the manufactured output. This thesis concentrates on this aspect of feedback. A preliminary customer survey revealed that the information received directly from customers might not be accurate enough to be used as primary feedback data. The quality of the information varies notably and depends entirely on the customers' ability to perceive the relevant parameters. This also affects greatly their ability to communicate the information to the customer interface and then all the way back to the manufacturer. Based on the findings, end customers' average level of knowledge of mobile phone technology is fair [C]. Therefore, it is recommended that more accurate means should be developed for acquiring feedback data. Also, based on other research findings, it would be important to minimize human intervention and to make the flow of information as direct as possible. Based on previous research and the present findings, a concept was designed which satisfies the specific need for accurate feedback from the performance of mobile phones in the field. The interfaces providing data throughout the whole product life cycle were also analyzed in detail. And finally, the concept was implemented and piloted with a mobile phone manufacturer. The pilot studies showed that an improved feedback capability would benefit not only product quality, but also various functions of the company producing mobile devices. The increased knowledge of device performance obtained from the system can be utilized in, for example, testing, design, marketing, and management and also at all customer interfaces in the field.

Silicon Carbide (SiC) is a wide-bandgap (WBG) semiconductor materialwhich has several advantages such as higher maximum electric field, lowerON-state resistance, higher switching speeds, and higher maximum allowablejunction operation temperature compared to Silicon (Si). In the 1.2 kV - 1.7kV voltage range, power devices in SiC are foreseen to replace Si Insulatedgatebipolar transistors (IGBTs) for applications targeting high efficiency,high operation temperatures and/or volume reductions. In particular, theSiC Metal-oxide semiconductor field-effect transistor (MOSFET) – which isvoltage controlled and normally-OFF – is the device of choice due to the easeof its implementation in designs using Si IGBTs.In this work the reliability of SiC devices, in particular that of the SiCMOSFET, has been investigated. First, the possibility of paralleling two discreteSiC MOSFETs is investigated and validated through static and dynamictests. Parallel-connection was found to be unproblematic. Secondly, drifts ofthe threshold voltage and forward voltage of the body diode of the SiC MOSFETare investigated through long-term tests. Also these reliability aspectswere found to be unproblematic. Thirdly, the impact of the package on thechip reliability is discussed through a modeling of the parasitic inductancesof a standard module and the impact of those inductances on the gate oxide.The model shows imbalances in stray inductances and parasitic elementsthat are problematic for high-speed switching. A long-term test on the impactof humidity on junction terminations of SiC MOSFETs dies and SiCSchottky dies encapsulated in the same standard package reveals early degradationfor some modules situated outdoors. Then, the short-circuit behaviorof three different types (bipolar junction transistor, junction field-effect transistor,and MOSFET) of 1.2 kV SiC switching devices is investigated throughexperiments and simulations. The necessity to turn OFF the device quicklyduring a fault is supported with a detailed electro-thermal analysis for eachdevice. Design guidelines towards a rugged and fast short-circuit protectionare derived. For each device, a short-circuit protection driver was designed,built and validated experimentally. The possibility of designing diode-lessconverters with SiC MOSFETs is investigated with focus on surge currenttests through the body diode. The discovered fault mechanism is the triggeringof the npn parasitic bipolar transistor. Finally, a life-cycle cost analysis(LCCA) has been performed revealing that the introduction of SiC MOSFETsin already existing IGBT designs is economically interesting. In fact,the initial investment is saved later on due to a higher efficiency. Moreover,the reliability is improved, which is beneficial from a risk-management pointof-view. The total investment over 20 years is approximately 30 % lower fora converter with SiC MOSFETs although the initial converter cost is 30 %higher.
Kiselkarbid (SiC) är ett bredbandgapsmaterial (WBG) som har flera fördelar,såsom högre maximal elektrisk fältstyrka, lägre ON-state resitans, högreswitch-hastighet och högre maximalt tillåten arbetstemperatur jämförtmed kisel (Si). I spänningsområdet 1,2-1,7 kV förutses att effekthalvledarkomponenteri SiC kommer att ersätta Si Insulated-gate bipolar transistorer(IGBT:er) i tillämpningar där hög verkningsgrad, hög arbetstemperatur ellervolymreduktioner eftersträvas. Förstahandsvalet är en SiC Metal-oxidesemiconductor field-effect transistor (MOSFET) som är spänningsstyrd ochnormally-OFF, egenskaper som möjliggör enkel implementering i konstruktionersom använder Si IGBTer.I detta arbete undersöks tillförlitligheten av SiC komponenter, specielltSiC MOSFET:en. Först undersöks möjligheten att parallellkoppla tvådiskretaSiC MOSFET:ar genom statiska och dynamiska prov. Parallellkopplingbefanns vara oproblematisk. Sedan undersöks drift av tröskelspänning ochbody-diodens framspänning genom långtidsprov. Ocksådessa tillförlitlighetsaspekterbefanns vara oproblematiska. Därefter undersöks kapslingens inverkanpåchip:et genom modellering av parasitiska induktanser hos en standardmoduloch inverkan av dessa induktanser pågate-oxiden. Modellen påvisaren obalans mellan de parasitiska induktanserna, något som kan varaproblematiskt för snabb switchning. Ett långtidstest av inverkan från fuktpåkant-termineringar för SiC-MOSFET:ar och SiC-Schottky-dioder i sammastandardmodul avslöjar tidiga tecken pådegradering för vissa moduler somvarit utomhus. Därefter undersöks kortslutningsbeteende för tre typer (bipolärtransistor,junction-field-effect transistor och MOSFET) av 1.2 kV effekthalvledarswitchargenom experiment och simuleringar. Behovet att stänga avkomponenten snabbt stöds av detaljerade elektrotermiska simuleringar för allatre komponenter. Konstruktionsriktlinjer för ett robust och snabbt kortslutningsskyddtas fram. För var och en av komponenterna byggs en drivkrets medkortslutningsskydd som valideras experimentellt. Möjligheten att konstrueradiodlösa omvandlare med SiC MOSFET:ar undersöks med fokus påstötströmmargenom body-dioden. Den upptäckta felmekanismen är ett oönskat tillslagav den parasitiska npn-transistorn. Slutligen utförs en livscykelanalys(LCCA) som avslöjar att introduktionen av SiC MOSFET:ar i existerandeIGBT-konstruktioner är ekonomiskt intressant. Den initiala investeringensparas in senare pågrund av en högre verkningsgrad. Dessutom förbättrastillförlitligheten, vilket är fördelaktigt ur ett riskhanteringsperspektiv. Dentotala investeringen över 20 år är ungefär 30 % lägre för en omvandlare medSiC MOSFET:ar även om initialkostnaden är 30 % högre.

QC 20170524

During development and testing of the functionality of the pacemaker and defibrillator device, engineers in the St. Jude Medical Cardiac Rhythm Management Division use an in-house development tool called Universal Engineering Programmer (UEP) to ensure the device functions as expected, before it can be used to test on an animal or a human during the implantation process. In addition, some applications of UEP are incorporated into the official releases of the device product. UEP has been developed and used by engineers across departments in the St. Jude Medical Cardiac Rhythm Management Division (CRMD). This thesis covers the flexible and reusable design and implementation of UEP features, to allow engineers to easily and effectively develop and test the devices.

Body mounted germanium substrate solar cell arrays form the faces of many small satellite designs to provide the primary power source on orbit. High efficiency solar cells are made affordable for university satellite programs as triangular devices trimmed from wafer scale solar cells. The smaller cells allow array designs to pack tightly around antenna mounts and payload instruments, giving the board design flexibility. One objective of this work is to investigate the reliability of solar cells attached to FR-4 printed circuit boards. FR-4 circuit boards have significantly higher thermal expansion coefficients and lower thermal conductivities than germanium. This thermal expansion coefficient mismatch between the FR-4 board and the components causes concern for the power system in terms of failures seen by the solar cells. These failures are most likely to occur with a longer orbital lifetime and an extended exposure to harsh environments. This work compares various methods of attaching solar cells to printed circuit boards, using solder paste alone and with a silicone adhesive, and considering the application of these adhesives by comparing the solder joints when printed by screen versus a stencil. An environmental test plan was used to compare the survivability and performance of the solar arrays.

The use of optical input/output (I/O) interconnects, in addition to electrical I/Os, is a promising approach for achieving high-bandwidth, chip-to-board communications required for future high-performance gigascale chip-based systems. While numerous efforts are underway to investigate the integration of optoelectronics and silicon microelectronics, virtually no work has been reported relating to testing of such chips. The objective of this research is to explore methods that enable wafer-level testing of gigascale chips having electrical and optical I/O interconnects. A major challenge in achieving this is to develop probe modules which would allow high-precision, temporary interconnection of a multitude of electrical and optical I/Os, in a chip-size area, to automated test equipment. A probe module would need to do this in a rapid, step-and-repeat manner across all the chips on the wafer. In this work, two candidate probe modules were devised, batch-fabricated on Si using microfabrication techniques, and successfully demonstrated. The first probe module consists of compliant electrical probes (10^3 probes/cm^2) fabricated alongside grating-in-waveguide optical probes. The second module consists of micro-opto-electro-mechanical-systems (MOEMS)-based microsocket probes (10^4 probes/cm^2) to interface a chip with polymer pillar-based electrical and optical I/Os. High-density through-wafer interconnects are an essential attribute in both probe substrates for transferring electrical and optical signals to the substrate back-side. Fabrication and characterization of metal-clad, metal-filled, and polymer-filled through-wafer interconnects as well as process integration with probe substrate fabrication are described and numerous possible redistribution schemes are explicated. Chips with optical and electrical I/Os are an emerging technology, and one that test engineers are likely to encounter in the near future. The contributions of this thesis are to help understand and address the issues relating to joint electrical and optical testing during manufacturing.

The new Field Programmable Gate Array (FPGA) technologies and their structures have opened up new approaches to logic design and synthesis. The main feature of an FPGA is an array of logic blocks surrounded by a programmable interconnection structure. Cellular FPGAs are a special class of FPGAs which are distinguished by their fine granularity and their emphasis on local cell interconnects. While these characteristics call for specialized synthesis tools, the availability of logic gates other than Boolean AND, OR and NOT in these architectures opens up new possibilities for synthesis. Among the possible realizations of Boolean functions, XOR logic is shown to be more compact than AND/OR and also highly testable. In this dissertation, the concept of structural regularity and the advantages of XOR logic are used to investigate various synthesis approaches to cellular FPGAs, which up to now have been mostly nonexistent. Universal XOR Canonical Forms, Two-level AND/XOR, restricted factorization, as well as various Directed Acyclic Graph structures are among the proposed approaches. In addition, a new comprehensive methodology for the investigation of all possible XOR canonical forms is introduced. Additionally, a new compact class of XOR-based Decision Diagrams for the representation of Boolean functions, called Kronecker Functional Decision Diagrams (KFDD), is presented. It is shown that for the standard, hard, benchmark examples, KFDDs are on average 35% more compact than Binary Decision Diagrams, with some reductions of up to 75% being observed.

A stability checker is a clocked storage element, much like a flip-flop, which detects unstable and late signals in the pipeline of a digital system. The On-line stability checker operates concurrently with its associated circuit-under-test (CUT). This thesis describes the full custom very-large-scale integration (VLSI) design and testing process of On-Line Stability Checkers. The goals of this thesis are to construct and test Stability Checker designs, and to create a design template for future class projects in the EE 431 Computer-Aided Design (CAD) of VLSI Devices course at Cal Poly. A method for concurrent fault testing called On-line Stability Checking was introduced by Franco and McCluskey [10] to detect reliability failures. Reliability failures initially manifest themselves as delay faults and transient glitching, which become progressively larger over time due to the wearout of conducting metal lines, eventually leading to functional faults. Stability checkers periodically detect reliability failures by monitoring CUT output signals for unstable and late input signals over a time period after the sampling clock edge. The checkers are tested by applying variable delayed input test patterns to emulate reliability failures. Consequently, configurable delay chains were incorporated into the system to provide variable delays on the input signal lines. The system also includes external test signal ports. Circuit and layout designs were implemented in the Electric VLSI Design tool [12] and simulated with LTSPICE [13]. Electric provides Design Rule Checking (DRC) and Layout-versus-Schematic (LVS) utilities for verification. Each module was designed in a bottom-up, hierarchical cell-based approach. Functional simulation, DRC and LVS checks were performed at every subsequent higher cell layer in the design hierarchy. The final chip layout was taped out for fabrication on November 29, 2010 and finished parts were received on July 7, 2011 after two manufacturing delays. Finished packaged parts were successfully verified for functionality based on SPICE simulations. The stability checkers were tested for flip-flop operation, glitch detection and late signal arrival detection. Configurable delay chains were tested to determine delay resolution and uniformity. Actual delay resolution and range measurements show a 3 to 4 times difference compared to simulated values. The Electric design template created from this project includes basic CMOS logic gates with uniform standard cell heights. The template contains a 40-pin pad ring cell along with the individual pad ring components. EE 431 students would be able to create custom chips that are compatible for fabrication via the MOSIS MEP service. In future work, the template design library can be expanded to include more logic gate variants of various inputs and drive strengths as well as more complex functional modules.

INTRODUCTION: While mobile device use by physicians increases, there is an increased risk that errors committed while using mobile devices can lead to harm. This mixed-method study evaluates the effects of screen size on clinical users’ perceptions of medical application usability and safety when interfacing to critical patient information. In this research, two mobile devices are examined: iPhone® and the iPad®. METHOD: Eleven physicians and one nurse practitioner participated in a chart-review simulation using an app that was an end-point to an electronic health record. Screen-recording, video-recording and a think-aloud protocol were used to gather data during the simulation. Additionally, participants completed Likert-based questionnaires and engaged in semi-structured interviews. RESULTS: A total of 105 usability, usefulness and safety problems were recorded and analysed. A strong preference was found for the larger screen when reviewing patient data due to the large quantity of data and the increased display size. The smaller device was preferred due to the devices portability when participants needed to remain informed when they were away from the point of care. CONCLUSION: There is an association between screen size and the perceived safety of the handheld device. The iPad was perceived to be safer to use in clinical practice. Participants preferred the iPad® because of the larger size, not because they thought it was safer or easier to use. The iPhone® was preferred for its portability and its usefulness was perceived to increase with greater distance from the point of care.
Graduate

New potential molecular electronics devices have been synthesized based on our knowledge of previous systems that have come out of our group. Previous studies and current studies have shown that simple molecular systems demonstrate negative differential resistance (NDR) and memory characteristics. The new systems rely primarily on the redox properties of the compounds to improve upon the solid state properties already observed. Most of these new organic compounds use thiol-based "alligator clips" for attachment to metal surfaces. Some of the compounds, however, contain different "alligator clips," primarily isonitriles, for attachment to metal substrates. It is our hope that these new "alligator clips" will offer lower conductivity barriers (higher current density). Electrochemical tests have been performed in order to evaluate those redox properties and in the hope of using those electrochemical results as a predictive tool to evaluate the usefulness of those compounds. Also, organic structures with polymerizable functionalities have been synthesized in order to cross-link the molecules once they are a part of a self-assembled monolayer (SAM). This has been shown to enable the electrochemical growth of polypyrrole from a SAM in a controllable manner.

Though declining in popularity over the last decade, the magnetron still has applications where portable high power is needed. This study examines the predicted performance of cylindrical microwave magnetrons using analytic lumped-spoke models based on the energy conservation principle. The analytic approach is still favoured when small computer systems are used and the overall performance of the tube is to be predicted. The magnetron elements are examined and the role they play in the overall device performance analysed. Simplified representations of these elements are used to construct a complete magnetron model. The Hartree threshold condition is reexamined and a new, more accurate analytic formulation proposed. This formulation is based on electric field strengths at the base of the magnetron spoke. The effect of the space charge on the threshold condition is included. Spoke current has been evaluated at the edge of the Brillouin hub. The resulting anode- cathode voltage performance predictions are consistent with measured results. A computer program has been written to analyse the performance predicted by this model. Models proposed by other authors are examined, and compared to this model. The resulting model has been tested by comparing predicted results to the measured performance of four slot-and-hole magnetrons. To facilitate accurate magnetron testing, a new automated triple-stub high power microwave load has been developed. The load operates at a peak power of IMW from 2,7-3,OGHZ, and allows the change of the VSWR to any value along any path within the VSWR=I, 5: I circle. The development of the triple tuner and termination is discussed in detail. A new waterload configuration which has the advantage of simple construction yet good matching characteristics is presented. Automated measurement of pulling figure and construction of Rieke diagrams is discussed. The accuracy of the complete load is compared to conventional loads currently in service in the tube industry.
Thesis (Ph.D.)-University of Natal, Durban, 1988.

Chapter 1 discusses advances in molecular scale electronics. With the miniaturization of transistors on silicon semiconductor chips comes faster processing speeds and more powerful computational power; however, certain size constraints on today's semiconductor industry will soon be realized. Therefore, a new method of computer architecture must be developed. The use of a discrete, highly conjugated organic molecule as a molecular scale wire to conduct an electric current has been demonstrated. We have developed molecular scale gates, from organic molecules, that can be altered "on" and "off" with the use of an electric field. Additionally, we have synthesized and tested nanoscale devices that exhibit negative differential resistance with a valley to peak ratio of over 1000:1 that is 10 times that of current solid-state devices and shown long lasting random access memory. The use of these molecular scale wires and devices should allow us to overcome the miniaturization barrier. Chapter 2 describes a simple bench-top gravity column chromatography method for the purification of C60, C70, and the higher fullerenes < C100. The stationary phase is based on poly(dibromostyrene)/divinylbenzene and the eluent is chlorobenzene. This new stationary phase (1) uses an inexpensive monomer that can be easily polymerized by standard suspension techniques, (2) permits the use of potent fullerene solvents, and (3) can be reused without additional preparation. Chapter 3 discusses the use of phenylene ethynylene oligomers as self assembled monolayer negative tone resist for the manufacture of even smaller semiconductor chips. With current methods of silicon etching with polymer resists, devices with sub-25 run feature size are not obtainable. We have prepared the first self-assembled monolayer that upon irradiation acts as a negative tone resist. In addition, we have synthesized a phenylene-ethynylene substituted trichlorosilane that should crosslink with exposure to irradiation to be a superior resist material. We are currently in the process of evaluating what functionalities are necessary to form negative tone resists at lower doses of energy. This will allow the fabrication of device feature sizes below 8 nm. Chapters 4, 5, and 6 discuss the great utility of substituted phenylene ethynylenes in the areas of cluster and surface binding study, STM patterning, and organic LEDs.

Here I report work done to develop an integrated amplitude and phase shaped optical frequency comb as a source for RF photonic signal processing. The first published section of work pushed towards integrated comb generation; in this work, InP devices were provided by Infinera corp., and SiN devices fabricated by professor Minghao Qi’s group. In this work a monolithic InP-based photonic integrated circuit (PIC) consisting of a widely tunable laser master oscillator feeding an array of integrated semiconductor optical amplifiers that are interferometrically combined on-chip in a single-mode waveguide is shown. We demonstrate a stable and efficient on-chip coherent beam combination and obtain up to 240 mW average power from the monolithic PIC, with 30–50 kHz Schawlow-Townes linewidths and >180 mW average power across the extended C-band. We also explored hybrid integration of the InP-based laser and amplifier array PIC with a high quality factor silicon nitride microring resonator. We observe lasing based on gain from the interferometrically combined amplifier array in an external cavity formed via feedback from the silicon nitride microresonator chip; this configuration results in narrowing of the Schawlow-Townes linewidth to 􀀀3 kHz with 37.9 mW average power at the SiN output facet. The pulse shaping was achieved using an InP ultrafast optical pulse shaper fabricated by Infinera corporation. In this work we report characterization of a 48 channel InP shaper at 50 GHz channel spacing, provisioned with both channel-by-channel phase adjusters and SOA gain elements. To our knowledge this constitutes the first demonstration of an operable integrated InP pulse shaper with independent intensity and phase control.

Based on rational design principles, diverse arrays of small organic oligomers containing unique electronics structures and redox functionalities have been synthesized for use in molecular-scale electronic device architectures. Thiol terminated oligoanilines were found to exhibit reproducible bistable switching behavior with an on-off ratio of > 10:1 at room temperature when biased between metal electrodes. The synthesis of orthogonally functionalized oligomers has resulted in compounds containing functionalities on one end known to form ordered self-assembled monolayers on metal surfaces while at the other end an intact thioacetate is present whereby self-assembly may again occur after an in situ deprotection for use in NanoCell electronic memories. The NanoCell devices were found to exhibit switching behavior when biased, with a two state memory; however the switching proved to be metallic in nature. Additionally, orthogonally functionalized oligomers allow for the covalent attachment of carbon nanotubes to silicon surfaces for possible uses in sensor and electronic device embodiments. This technique relies on the ability to graft aryldiazonium salts onto a silicon hydride passivated surface followed by diazotization of the terminal aniline. Organic aryltriazenes have been shown to assemble on hydride passivated silicon surfaces by using an in situ diazotization protocol in dilute HF solution. Film thicknesses range from a monolayer to 200 nm depending on conditions. Novel U-shape oligomers have been synthesized to aid in the elucidation of molecular switching behavior and monolayer film formation using advanced surface characterization techniques. These conformationally restricted oligomers are designed to be of use in studies utilizing scanning probe microscopy techniques to elucidate switching mechanisms and negative differential resistance behavior thought to be based on molecular conformational changes.

碩士
國立清華大學
工業工程與工程管理學系
99
According to Espicom Business Intelligence surveys, the medical device global market size was 224.1 Billion USD in 2009, and it is estimated to achieve 294.4 billion USD in 2014, the CAGR (Compound Annual Growth Rate) can be 7.3%. Besides that, more and more famous Taiwanese Electronics companies attracted to involve in medical device market are almost focusing on electronic medical devices because of that medical device industry belongs to high benefit return rate industries. Therefore, the issue is arising as the followings --- what are the main advantages of famous electronics companies to invest into medical device market? This research adopts case study to find out what are the case’ management strategies and future development trend by studying the diabetic diagnosis market which the case involved in at the first step, and then high light the challenges and management strategies that electronics companies planning to involved in medical device will be facing via studying the case. As the result, there are four main key points in the conclusion: 1. Companies can get family with products verification and quality management process to shorten the learning lead time via merger and acquisition strategies. 2. Key components expanded from code technology providing model helps companies cut in and position in the international medical device value chain. 3. Investing in innovative medical products R&D, it means tending towards high level medical device development 4. To broaden business size and increase the market share via merging other companies.

The widespread use of Liquid Petroleum Gas (LPG) for cooking and as fuel for automobile vehicles requires fast and selective detection of LPG to precisely measure the leakage of gas for preventing the occurrence of accidental explosions. The adoption of Micro-Electro-Mechanical-System (MEMS) technology for fabricating the gas sensor provides other potential advantages for sensing applications, which includes low power consumption, low fabrication cost, high quality, small size and reliability. MEMS based gas sensor requires a sensitive layer of oxide material like ZnO, SnO2, TiO2, Fe2O3, etc. The tin oxide material used in the present work changes its electrical properties, as it interacts with the reducing gas like LPG. The sensor material becomes active only at high temperature such as 400ºC, thereby realizing the need of a micro heater to reach the desired temperature. To control the temperature of micro heater and to determine the change in electrical properties of the sensor due to its interaction with LPG an Application Specific Integrated Circuit (ASIC) forms an essential constituent of the MEMS based gas sensor. In the present work, an attempt has been made to improve the sensitivity of LPG gas sensor and it is correlated with other properties by different characterization techniques. The work also includes the design as well as testing of ASIC for gas sensor system. Process parameters particularly deposition time and substrate temperature have a profound influence on the microstructure of the tin oxide film, which in turn affects the gas sensing properties. To study the effects of these parameters, RF magnetron sputtering system is used for depositing tin oxide films onto the silicon substrate, which is compatible with CMOS technology. The effects of structural properties, optical properties and the porosity of the films are also studied and correlated with the gas sensing properties. In this direction the deposited films are characterized using X-Ray Diffraction (XRD) to determine the structure orientation. The morphology of the sensor films are analyzed by Scanning Electron Microscope (SEM) while the refractive index, thickness and porosity of the films are determined using ellipsometry studies. The thickness of the deposited films is also confirmed by the surface profilometer. The change in composition of the deposited film along its depth is determined using Secondary Ion Mass Spectrometer (SIMS). Maximum sensitivity 5.5 is obtained for 470 nm thick films, which corresponds to a grain size of 38nm at the operating temperature of 4000C. Following these studies, an ASIC has been designed using Tanner EDA Tools on AMIS 0.7 µm CMOS process, fabricated through Euro practice’s ASIC prototyping service, Belgium and tested successfully after fabrication. The temperature control module of ASIC has been designed using relaxation oscillator technique to control the temperature of the in house developed heater. The resistance to period conversion technique is explored for the design of the sensor read out module of ASIC. The heater is integrated successfully with the sensor film, ASIC and microcontroller based LCD module. The test results show good agreement with the simulation results.