Articoli di riviste: "HEMT AlN"

1

Chiu, Hsien-Chin, Chia-Hao Liu, Chong-Rong Huang, Chi-Chuan Chiu, Hsiang-Chun Wang, Hsuan-Ling Kao, Shinn-Yn Lin e Feng-Tso Chien. "Normally-Off p-GaN Gated AlGaN/GaN MIS-HEMTs with ALD-Grown Al2O3/AlN Composite Gate Insulator". Membranes 11, n. 10 (23 settembre 2021): 727. http://dx.doi.org/10.3390/membranes11100727.

Testo completo

Abstract (sommario):

A metal–insulator–semiconductor p-type GaN gate high-electron-mobility transistor (MIS-HEMT) with an Al2O3/AlN gate insulator layer deposited through atomic layer deposition was investigated. A favorable interface was observed between the selected insulator, atomic layer deposition–grown AlN, and GaN. A conventional p-type enhancement-mode GaN device without an Al2O3/AlN layer, known as a Schottky gate (SG) p-GaN HEMT, was also fabricated for comparison. Because of the presence of the Al2O3/AlN layer, the gate leakage and threshold voltage of the MIS-HEMT improved more than those of the SG-HEMT did. Additionally, a high turn-on voltage was obtained. The MIS-HEMT was shown to be reliable with a long lifetime. Hence, growing a high-quality Al2O3/AlN layer in an HEMT can help realize a high-performance enhancement-mode transistor with high stability, a large gate swing region, and high reliability.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Yamaoka, Yuya, Kazuhiro Ito, Akinori Ubukata, Toshiya Tabuchi, Koh Matsumoto e Takashi Egawa. "Effect of the formation temperature of the AlN/Si interface on the vertical-direction breakdown voltages of AlGaN/GaN HEMTs on Si substrates". MRS Advances 1, n. 50 (2016): 3415–20. http://dx.doi.org/10.1557/adv.2016.431.

Testo completo

Abstract (sommario):

ABSTRACT In this study, the initial AlN layer and the vertical-direction breakdown voltage (VDBV) of AlGaN/GaN high-electron-mobility transistors (HEMTs) were characterized. Prior to the formation of the interface between the AlN layer and the Si substrate, only trimethylaluminum (TMA) was introduced without ammonia to control the crystal quality of initial AlN layer (TMA preflow). HEMT structures were simultaneously grown on identical AlN layers on Si substrates (AlN/Si templates) grown using different TMA preflow temperatures. The density of screw- or mixed-type dislocations in the initial AlN layer decreased as the TMA preflow temperature increased. Further, the VDBV of the HEMT structure increased as the TMA preflow temperature increased. It is supposed that the screw- or mixed-type dislocations are the possible source of the vertical leakage current in the HEMT structures. The improvement in the crystal quality of the initial AlN layer affects the increase in the VDBV of the AlGaN/GaN HEMTs on Si substrates.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Çörekçi, S., D. Usanmaz, Z. Tekeli, M. Çakmak, S. Özçelik e E. Özbay. "Surface Morphology of Al0.3Ga0.7N/Al2O3-High Electron Mobility Transistor Structure". Journal of Nanoscience and Nanotechnology 8, n. 2 (1 febbraio 2008): 640–44. http://dx.doi.org/10.1166/jnn.2008.a181.

Testo completo

Abstract (sommario):

We present surface properties of buffer films (AlN and GaN) and Al0.3Ga0.7N/Al2O3-High Electron Mobility Transistor (HEMT) structures with/without AlN interlayer grown on High Temperature (HT)-AlN buffer/Al2O3 substrate and Al2O3 substrate. We have found that the GaN surface morphology is step-flow in character and the density of dislocations was about 108–109 cm−2. The AFM measurements also exhibited that the presence of atomic steps with large lateral step dimension and the surface of samples was smooth. The lateral step sizes are in the range of 100–250 nm. The typical rms values of HEMT structures were found as 0.27, 0.30, and 0.70 nm. HT-AlN buffer layer can have a significant impact on the surface morphology of Al0.3Ga0.7N/Al2O3-HEMT structures.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Shrestha, Niraj Man, Yuen Yee Wang, Yiming Li e E. Y. Chang. "Simulation Study of AlN Spacer Layer Thickness on AlGaN/GaN HEMT". Himalayan Physics 4 (22 dicembre 2013): 14–17. http://dx.doi.org/10.3126/hj.v4i0.9419.

Testo completo

Abstract (sommario):

High electron mobility transistor (HEMT)Two-dimensional electron gas (2DEG) formed at AlGaN/GaN interface is a critical part to tune the characteristic of AlGaN/GaN HEMT devices. Introduction of AlN spacer layer in between AlGaN and GaN layer is one of the way to improve 2DEG density, mobility, and drain current. Carrier concentration, mobility and conduction band offset for different spacer layer thickness was simulated by using Silvaco simulation tool. Our device simulations showed that carrier concentration, mobility are enhance on introduction of AlN spacer layer in HEMT. In addition, carrier properties of HEMT also depend on thickness of spacer layer. Our simulation showed that the mobility of 2DEG attains its maximum value at the 0.5 nm thick AlN layer but carrier concentration increases with spacer thickness. Finally, drain current increases with increasing spacer layer thickness and reach maximum value at 1.2nm thick spacer layer.The Himalayan Physics Vol. 4, No. 4, 2013 Page: 14-17 Uploaded date: 12/22/2013

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Tsai, Jung-Hui, Jing-Shiuan Niu, Xin-Yi Huang e Wen-Chau Liu. "Comparative Investigation of AlGaN/AlN/GaN High Electron Mobility Transistors with Pd/GaN and Pd/Al2O3/GaN Gate Structures". Science of Advanced Materials 13, n. 2 (1 febbraio 2021): 289–93. http://dx.doi.org/10.1166/sam.2021.3856.

Testo completo

Abstract (sommario):

In this article, the electrical characteristics of Al0.28Ga0.72 N/AlN/GaN metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT) with a 20-nm-thick Al2O3 layer by using radio-frequency sputtering as the gate dielectric layer are compared to the conventional metal-semiconductor HEMT (MS-HEMT) with Pd/GaN gate structure. For the insertion of the Al2O3 layer, the energy band near the AlN/GaN heterojunction is lifted slightly up and the 2DEG at the heterojunction is reduced to shift the threshold voltage to the right side. Experimental results exhibits that though the maximum drain current decreases about 6.5%, the maximum transconductance increases of 9%, and the gate leakage current significantly reduces about five orders of magnitude for the MOS-HEMT than the MS-HEMT.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Hong, Kuo-Bin, Chun-Yen Peng, Wei-Cheng Lin, Kuan-Lun Chen, Shih-Chen Chen, Hao-Chung Kuo, Edward Yi Chang e Chun-Hsiung Lin. "Thermal Analysis of Flip-Chip Bonding Designs for GaN Power HEMTs with an On-Chip Heat-Spreading Layer". Micromachines 14, n. 3 (23 febbraio 2023): 519. http://dx.doi.org/10.3390/mi14030519.

Testo completo

Abstract (sommario):

In this work, we demonstrated the thermal analysis of different flip-chip bonding designs for high power GaN HEMT developed for power electronics applications, such as power converters or photonic driver applications, with large gate periphery and chip size, as well as an Au metal heat-spreading layer deposited on top of a planarized dielectric/passivation layer above the active region. The Au bump patterns can be designed with high flexibility to provide more efficient heat dissipation from the large GaN HEMT chips to an AlN package substrate heat sink with no constraint in the alignment between the HEMT cells and the thermal conduction bumps. Steady-state thermal simulations were conducted to study the channel temperatures of GaN HEMTs with various Au bump patterns at different levels of current and voltage loadings, and the results were compared with the conventional face-up GaN die bonding on an AlN package substrate. The simulations were started from a single finger isolated HEMT cell and then extended to multiple fingers HEMT cells (total gate width > 40 mm) to investigate the “thermal cross-talk” effect from neighboring devices. Thermal analysis of the GaN HEMT under pulse operation was also performed to better reflect the actual conditions in power conversion or pulsed laser driver applications. Our analysis provides a combinational assessment of power GaN HEMT dies under a working condition (e.g., 1MHz, 25% duty cycle) with different flip chip packaging schemes. The analysis indicated that the channel temperature rise (∆T) of a HEMT cell in operation can be reduced by 44~46% by changing from face-up die bonding to a flip-chip bonding scheme with an optimized bump pattern design.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Gusev, A. S., A. O. Sultanov, A. V. Katkov, S. M. Ryndya, N. V. Siglovaya, A. N. Klochkov, R. V. Ryzhuk, N. I. Kargin e D. P. Borisenko. "Carrier Scattering Analysis in AlN/GaN HEMT Heterostructures with an Ultrathin AlN Barrier". Mikroèlektronika 53, n. 3 (27 ottobre 2024): 265–73. http://dx.doi.org/10.31857/s0544126924030086.

Testo completo

Abstract (sommario):

Experimental AlN/GaN heterostructures (HSs) with an ultrathin AlN barrier were obtained using molecular beam epitaxy with plasma activation of nitrogen. The layer resistance of the optimized structures was less than 230 Ω/¨. The scattering processes that limit the mobility of two-dimensional electron gas in undoped AlN/GaN HSs with an ultrathin AlN barrier have been studied. It is shown that in the ns range characteristic of AlN/GaN HEMT HSs (ns 1 × 1013 cm–2), a noticeable contribution to the scattering of charge carriers is made by the roughness of the heterointerface.

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Roensch, Sebastian, Victor Sizov, Takuma Yagi, Saad Murad, Lars Groh, Stephan Lutgen, Michael Krieger e Heiko B. Weber. "Impact of AlN Spacer on Electron Mobility of AlGaN/AlN/GaN Structures on Silicon". Materials Science Forum 740-742 (gennaio 2013): 502–5. http://dx.doi.org/10.4028/www.scientific.net/msf.740-742.502.

Testo completo

Abstract (sommario):

The impact of the thickness of an AlN spacer in AlGaN/AlN/GaN high electron mobility transistor (HEMT) structures on the Hall mobility was investigated in a range of 30 K - 340 K. The AlN spacer has a strong impact on the mobility at temperatures below 150 K. This effect is linked to a reduction of alloy scattering. Optical and scanning electron microscopy revealed hexagonal shaped defects which also have an effect on the mobility. These defects can be avoided by an appropriate adjustment of the AlN layer thickness.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Михайлович, С. В., Р. Р. Галиев, А. В. Зуев, А. Ю. Павлов, Д. С. Пономарев e Р. А. Хабибуллин. "Влияние длины затвора на скорость инжекции электронов в каналах полевых транзисторов на основе AlGaN/AlN/GaN". Письма в журнал технической физики 43, n. 16 (2017): 9. http://dx.doi.org/10.21883/pjtf.2017.16.44927.16727.

Testo completo

Abstract (sommario):

Исследованы полевые транзисторы с высокой подвижностью электронов (HEMT) на основе AlGaN/AlN/GaN с разной длиной затвора Lg. Значения максимальных частот усиления по току fT и однонаправленного коэффициента усиления fmax составили 88 и 155 GHz для транзисторов с Lg =125 nm и 26 и 82 GHz для транзисторов с Lg = 360 nm соответственно. На основе измеренных S-параметров проведена экстракция значений элементов малосигнальных эквивалентных схем AlGaN/AlN/GaN HEMT и определена зависимость скорости инжекции vinj от напряжения затвор-исток. Также исследовано влияние длины затвора и напряжения между стоком и истоком на величину vinj. DOI: 10.21883/PJTF.2017.16.44927.16727

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Shen, L., S. Heikman, B. Moran, R. Coffie, N. Q. Zhang, D. Buttari, I. P. Smorchkova, S. Keller, S. P. DenBaars e U. K. Mishra. "AlGaN/AlN/GaN high-power microwave HEMT". IEEE Electron Device Letters 22, n. 10 (ottobre 2001): 457–59. http://dx.doi.org/10.1109/55.954910.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Eustis, Tyler J., John Silcox, Michael J. Murphy e William J. Schaff. "Evidence From EELS of Oxygen in the Nucleation Layer of a MBE Grown III-N HEMT". MRS Internet Journal of Nitride Semiconductor Research 5, S1 (2000): 188–94. http://dx.doi.org/10.1557/s1092578300004269.

Testo completo

Abstract (sommario):

The presence of oxygen throughout the nominally AlN nucleation layer of a RF assisted MBE grown III-N HEMT was revealed upon examination by Electron Energy Loss Spectroscopy (EELS) in a Scanning Transmission Electron Microscope (STEM). The nucleation layer generates the correct polarity (gallium face) required for producing a piezoelectric induced high mobility two dimensional electron gas at the AlGaN/GaN heterojunction. Only AlN or AlGaN nucleation layers have provided gallium face polarity in RF assisted MBE grown III-N’s on sapphire. The sample was grown at Cornell University in a Varian GenII MBE using an EPI Uni-Bulb nitrogen plasma source. The nucleation layer was examined in the Cornell University STEM using Annular Dark Field (ADF) imaging and Parallel Electron Energy Loss Spectroscopy (PEELS). Bright Field TEM reveals a relatively crystallographically sharp interface, while the PEELS reveal a chemically diffuse interface. PEELS of the nitrogen and oxygen K-edges at approximately 5-Angstrom steps across the GaN/AlN/sapphire interfaces reveals the presence of oxygen in the AlN nucleation layer. The gradient suggests that the oxygen has diffused into the nucleation region from the sapphire substrate forming this oxygen containing AlN layer. Based on energy loss near edge structure (ELNES), oxygen is in octahedral interstitial sites in the AlN and Al is both tetrahedrally and octahedrally coordinated in the oxygen rich region of the AlN.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Reilly, Caroline E., Nirupam Hatui, Thomas E. Mates, Shuji Nakamura, Steven P. DenBaars e Stacia Keller. "2DEGs formed in AlN/GaN HEMT structures with AlN grown at low temperature". Applied Physics Letters 118, n. 22 (31 maggio 2021): 222103. http://dx.doi.org/10.1063/5.0050584.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Popok, V. N., T. S. Aunsborg, R. H. Godiksen, P. K. Kristensen, R. R. Juluri, P. Caban e K. Pedersen. "Structural Characterization of Movpe Grown Algan/Gan for Hemt Formation". REVIEWS ON ADVANCED MATERIALS SCIENCE 57, n. 1 (1 giugno 2018): 72–81. http://dx.doi.org/10.1515/rams-2018-0049.

Testo completo

Abstract (sommario):

Abstract Results on structural, compositional, optical and electrical characterization of MOVPE grown AlGaN/GaN heterostructures with focus on understanding how the AlN buffer synthesis affects the top films are reported. The study demonstrates very good correlation between different methods providing a platform for reliable estimation of crystalline quality of the AlGaN/GaN structures and related to that electrical performance which is found to be significantly affected by threading dislocations (TD): higher TD density reduces the electron mobility while the charge carrier concentration is found to be largely unchanged. The attempt to vary the ammonia flow during the AlN synthesis is found not to affect the film composition and dislocation densities in the following heterostructures. An unusual phenomenon of considerable diffusion of Ga from the GaN film into the AlN buffer is found in all samples under the study. The obtained results are an important step in optimization of AlGaN/GaN growth towards the formation of good quality HEMT structures on sapphire and transfer of technology to Si substrates by providing clear understanding of the role of synthesis parameter on structure and composition of the films.

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Wang, X. H., X. L. Wang, C. Feng, C. B. Yang, B. Z. Wang, J. X. Ran, H. L. Xiao, C. M. Wang e J. X. Wang. "Hydrogen sensors based on AlGaN/AlN/GaN HEMT". Microelectronics Journal 39, n. 1 (gennaio 2008): 20–23. http://dx.doi.org/10.1016/j.mejo.2007.10.022.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Singhal, Jashan, Reet Chaudhuri, Austin Hickman, Vladimir Protasenko, Huili Grace Xing e Debdeep Jena. "Toward AlGaN channel HEMTs on AlN: Polarization-induced 2DEGs in AlN/AlGaN/AlN heterostructures". APL Materials 10, n. 11 (1 novembre 2022): 111120. http://dx.doi.org/10.1063/5.0121195.

Testo completo

Abstract (sommario):

Due to its high breakdown electric field, the ultra-wide bandgap semiconductor AlGaN has garnered much attention recently as a promising channel material for next-generation high electron mobility transistors (HEMTs). A comprehensive experimental study of the effects of Al composition x on the transport and structural properties is lacking. We report the charge control and transport properties of polarization-induced 2D electron gases (2DEGs) in strained AlGaN quantum well channels in molecular-beam-epitaxy-grown AlN/Al xGa1− xN/AlN double heterostructures by systematically varying the Al content from x = 0 (GaN) to x = 0.74, spanning energy bandgaps of the conducting HEMT channels from 3.49 to 4.9 eV measured by photoluminescence. This results in a tunable 2DEG density from 0 to 3.7 × 1013 cm2. The room temperature mobilities of x ≥ 0.25 AlGaN channel HEMTs were limited by alloy disorder scattering to below 50 cm2/(V.s) for these 2DEG densities, leaving ample room for further heterostructure design improvements to boost mobilities. A characteristic alloy fluctuation energy of [Formula: see text] eV for electron scattering in AlGaN alloy is estimated based on the temperature dependent electron transport experiments.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Gowthami, Y., B.Balaji e K. Srinivasa Rao. "Qualitative Analysis & Advancement of Asymmetric Recessed Gates with Dual Floating Material GaN HEMT for Quantum Electronics". Journal of Integrated Circuits and Systems 18, n. 1 (22 maggio 2023): 1–8. http://dx.doi.org/10.29292/jics.v18i1.657.

Testo completo

Abstract (sommario):

The Impact of Aluminium nitride (AlN) Spacer, Gallium Nitride (GaN) Cap Layer, Front Pi Gate (FG) and Back Pi Gate(BG), High K dielectric material such as Hafnium dioxide(HfO2), Aluminium Oxide (Al2O3), Silicon nitride (Si3N4) on Aluminium Galium Nitride/ Gallium Nitride (AlGaN/GaN), Heterojunction High Electron Mobility Transistor (HEMT) of 6nm(nanometer) technology is simulated and extracted the results using the Silvaco Atlas TCAD tool. The importance of High K dielectric materials like Al2O3 and Si3N4 are studied for the proposal of GaN HEMT. AlN, GaN Cap Layers, and High K Dielectric material are layered one on another to overcome the conventional transistor draw backs like surface defects, scattering of the electron, and less mobility of electron. Hot electron effect is overcome by Pi type gate. Therefore, by optimizing the HEMT structure the abilities for certain devices are converted to abilities. The dependency on DC characteristics and RF characteristics due to GaN Cap Layers, Multi gate (FG &BG), and High K Dielectric material is established. Further Compared Single Gate (SG) Passivated HEMT, Double Gate (DG) Passivated HEMT, Double Gate Triple(DGT) Tooth Passivated HEMT, High K Dielectric Front Pi Gate (FG) and Back Pi Gate (BG) Nanowire HEMT. It is observed that there is an increased Drain Current (Ion) of 5.92(A/mm), low Leakage current(Ioff) 5.54E-13 (A) of Transconductance (Gm) of 3.71(S/mm), Drain Conductance (Gd) of 1.769(S/mm), Cutoff frequency(fT) of 743 GHz Maximum Oscillation frequency (Fmax) 765 GHz, Minimum Threshold Voltage (Vth) of -4.5V, On Resistance (Ron)of 0.40(Ohms) at Vgs =0V. These outstanding characteristics and transistor structure of proposed HEMT and materials involved to apply for upcoming generation High-speed GHz frequency applications.

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Choi, Uiho, Kyeongjae Lee, Taemyung Kwak, Donghyeop Jung, Taehoon Jang, Yongjun Nam, Byeongchan So et al. "Growth behavior of GaN on AlN for fully coalesced channel of AlN-based HEMT". Japanese Journal of Applied Physics 58, n. 12 (6 novembre 2019): 121003. http://dx.doi.org/10.7567/1347-4065/ab4df3.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Wu, Jui Sheng, e Edward Yi Chang. "Demonstration of High Interface Quality AlGaN/GaN MIS-HEMT with Fully Wet Recess and MOCVD Grown AlN Dielectric". Materials Science Forum 1055 (4 marzo 2022): 7–12. http://dx.doi.org/10.4028/p-180hme.

Testo completo

Abstract (sommario):

In this study, the results indicate that a method combining fully-recessed wet etching and regrown channel by MOCVD is capable of obtaining high quality interface in GaN MIS-HEMT. A low Vth hysterisis GaN MIS-HEMT of 0.3V is demonstrated in this work. The GaN MIS-HEMT has a Vth of-1.5 V, a high Id,max of 771mA/mm and a RON of 13.5 Ω·mm. The wet etching shows good uniformity while the MOCVD grown AlN enhances the maximum drain current. The concept provides new insights to gate recess fabrication and MOCVD grown high quality dielectrics.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Lu, Hao, Ling Yang, Bin Hou, Meng Zhang, Mei Wu, Xiao-Hua Ma e Yue Hao. "AlN/GaN/InGaN coupling-channel HEMTs with steep subthreshold swing of sub-60 mV/decade". Applied Physics Letters 120, n. 17 (25 aprile 2022): 173502. http://dx.doi.org/10.1063/5.0088585.

Testo completo

Abstract (sommario):

This work reports an AlN/GaN/InGaN high electron mobility transistor (HEMT) with a steep subthreshold swing (SS) of sub-60 mV/dec utilizing a coupling-channel architecture. The fabricated transistors show a negligible hysteresis, a SS of 39 mV/dec, a large gate voltage swing of >4.2 V, and achieving an excellent quality factor Q = gm/SS of 6.3 μS-dec/ μm-mV. The negative differential resistance effect was found in the subthreshold region in the gate current–voltage ( Ig– VGS) curve. The hot carrier transfer mechanism that occurred in the turn-on/pinch-off progress of the CC-HEMT under the dual-directional sweep, proved by the VDS- and Lg-dependent bi-directional transfer I–V characteristics, can be responsible for these excellent device performances. This work is believed to encourage further study of the AlN/GaN platform to power the future group III-nitrides CMOS technology.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Lu, Hao, Ling Yang, Bin Hou, Meng Zhang, Mei Wu, Xiao-Hua Ma e Yue Hao. "AlN/GaN/InGaN coupling-channel HEMTs with steep subthreshold swing of sub-60 mV/decade". Applied Physics Letters 120, n. 17 (25 aprile 2022): 173502. http://dx.doi.org/10.1063/5.0088585.

Testo completo

Abstract (sommario):

This work reports an AlN/GaN/InGaN high electron mobility transistor (HEMT) with a steep subthreshold swing (SS) of sub-60 mV/dec utilizing a coupling-channel architecture. The fabricated transistors show a negligible hysteresis, a SS of 39 mV/dec, a large gate voltage swing of >4.2 V, and achieving an excellent quality factor Q = gm/SS of 6.3 μS-dec/ μm-mV. The negative differential resistance effect was found in the subthreshold region in the gate current–voltage ( Ig– VGS) curve. The hot carrier transfer mechanism that occurred in the turn-on/pinch-off progress of the CC-HEMT under the dual-directional sweep, proved by the VDS- and Lg-dependent bi-directional transfer I–V characteristics, can be responsible for these excellent device performances. This work is believed to encourage further study of the AlN/GaN platform to power the future group III-nitrides CMOS technology.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Sun, Mengyuan, Luyu Wang, Penghao Zhang e Kun Chen. "Improving Performance of Al2O3/AlN/GaN MIS HEMTs via In Situ N2 Plasma Annealing". Micromachines 14, n. 6 (23 maggio 2023): 1100. http://dx.doi.org/10.3390/mi14061100.

Testo completo

Abstract (sommario):

A novel monocrystalline AlN interfacial layer formation method is proposed to improve the device performance of the fully recessed-gate Al2O3/AlN/GaN Metal-Insulator-Semiconductor High Electron Mobility Transistors (MIS-HEMTs), which is achieved by plasma-enhanced atomic layer deposition (PEALD) and in situ N2 plasma annealing (NPA). Compared with the traditional RTA method, the NPA process not only avoids the device damage caused by high temperatures but also obtains a high-quality AlN monocrystalline film that avoids natural oxidation by in situ growth. As a contrast with the conventional PELAD amorphous AlN, C-V results indicated a significantly lower interface density of states (Dit) in a MIS C-V characterization, which could be attributed to the polarization effect induced by the AlN crystal from the X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM) characterizations. The proposed method could reduce the subthreshold swing, and the Al2O3/AlN/GaN MIS-HEMTs were significantly enhanced with ~38% lower on-resistance at Vg = 10 V. What is more, in situ NPA provides a more stable threshold voltage (Vth) after a long gate stress time, and ΔVth is inhibited by about 40 mV under Vg,stress = 10 V for 1000 s, showing great potential for improving Al2O3/AlN/GaN MIS-HEMT gate reliability.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Vohra, Anurag, Karen Geens, Ming Zhao, Olga Syshchyk, Herwig Hahn, Dirk Fahle, Benoit Bakeroot et al. "Epitaxial buffer structures grown on 200 mm engineering substrates for 1200 V E-mode HEMT application". Applied Physics Letters 120, n. 26 (27 giugno 2022): 261902. http://dx.doi.org/10.1063/5.0097797.

Testo completo

Abstract (sommario):

In this work, we demonstrate the epitaxial growth of a gallium-nitride (GaN) buffer structure qualified for 1200 V applications on 200 mm engineered poly-AlN substrates with hard breakdown >1200 V. The manufacturability of a 1200 V qualified buffer structure opens doors to high voltage GaN-based power applications such as in electric cars. Key to achieving the high breakdown voltage is careful engineering of the complex epitaxial material stack in combination with the use of 200 mm engineered poly-AlN substrates. The CMOS-fab friendly engineered poly-AlN substrates have a coefficient of thermal expansion (CTE) that closely matches the CTE of the GaN/AlGaN epitaxial layers, paving the way for a thicker buffer structure on large diameter substrates, while maintaining the mechanical strength of the substrates and reaching higher voltage operation.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Kim, Jeong-Gil, Chul-Ho Won, Do-Kywn Kim, Young-Woo Jo, Jun-Hyeok Lee, Yong-Tae Kim, Sorin Cristoloveanu e Jung-Hee Lee. "Growth of AlN/GaN HEMT structure Using Indium-surfactant". JSTS:Journal of Semiconductor Technology and Science 15, n. 5 (30 ottobre 2015): 490–96. http://dx.doi.org/10.5573/jsts.2015.15.5.490.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Durukan, İ. Kars, Ö. Akpınar, C. Avar, A. Gultekin, M. K. Öztürk, S. Özçelik e E. Özbay. "Analyzing the AlGaN/AlN/GaN Heterostructures for HEMT Applications". Journal of Nanoelectronics and Optoelectronics 13, n. 3 (1 marzo 2018): 331–34. http://dx.doi.org/10.1166/jno.2018.2239.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Hao, Lu, Zhihong Liu, Hanghai Du, Shenglei Zhao, Han Wang, Jincheng Zhang e Yue Hao. "Improvement of the Thermal Performance of the GaN-on-Si Microwave High-Electron-Mobility Transistors by Introducing a GaN-on-Insulator Structure". Micromachines 15, n. 12 (21 dicembre 2024): 1525. https://doi.org/10.3390/mi15121525.

Testo completo

Abstract (sommario):

GaN-on-Si high-electron-mobility transistors have emerged as the next generation of high-powered and cost-effective microwave devices; however, the limited thermal conductivity of the Si substrate prevents the realization of their potential. In this paper, a GaN-on-insulator (GNOI) structure is proposed to enhance the heat dissipation ability of a GaN-on-Si HEMT. Electrothermal simulation was carried out to analyze the thermal performance of the GNOI-on-Si HEMTs with different insulator dielectrics, including SiO2, SiC, AlN, and diamond. The thermal resistance of the HEMTs was found to be able to be obviously reduced and the DC performance of the device can be obviously improved by removing the low-thermal-conductivity III-nitride transition layer and forming a GNOI-on-Si structure with SiC, AlN, or diamond as the bonding insulator dielectrics.

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Guo, Lunchun, Xiaoliang Wang, Cuimei Wang, Hongling Xiao, Junxue Ran, Weijun Luo, Xiaoyan Wang, Baozhu Wang, Cebao Fang e Guoxin Hu. "The influence of 1nm AlN interlayer on properties of the Al0.3Ga0.7N/AlN/GaN HEMT structure". Microelectronics Journal 39, n. 5 (maggio 2008): 777–81. http://dx.doi.org/10.1016/j.mejo.2007.12.005.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Gusev, A. S., A. O. Sultanov, A. V. Katkov, S. M. Ryndya, N. V. Siglovaya, A. N. Klochkov, R. V. Ryzhuk, N. I. Kargin e D. P. Borisenko. "Analysis of Carrier Scattering Mechanisms in AlN/GaN HEMT Heterostructures with an Ultrathin AlN Barrier". Russian Microelectronics 53, n. 3 (giugno 2024): 252–59. http://dx.doi.org/10.1134/s1063739724600304.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Elwaradi, Reda, Jash Mehta, Thi Huong Ngo, Maud Nemoz, Catherine Bougerol, Farid Medjdoub e Yvon Cordier. "Effects of GaN channel downscaling in AlGaN–GaN high electron mobility transistor structures grown on AlN bulk substrate". Journal of Applied Physics 133, n. 14 (14 aprile 2023): 145705. http://dx.doi.org/10.1063/5.0147048.

Testo completo

Abstract (sommario):

In this work, two series of AlGaN/GaN/AlN high electron mobility transistor (HEMT) heterostructures have been grown by molecular beam epitaxy on AlN bulk substrates. The effects of reduction in the GaN channel thickness as well as the AlGaN barrier thickness and composition on structural and electrical properties of the heterostructures have been studied. The material analysis involved high-resolution x-ray diffraction, atomic force microscopy, and cross-sectional transmission electron microscopy. In a first series of HEMT structures grown with an aluminum content of 30% in the AlGaN barrier, the channel downscaling results in a reduction in the GaN strain relaxation rate but at the expense of degradation in the mean crystal quality and in the electron mobility with a noticeable increase in the sheet resistance. An opposite trend is noticed for the three-terminal breakdown voltage of transistors, so that a trade-off is obtained for a 50 nm width GaN channel HEMT, which exhibits a sheet resistance of 1700 Ω/sq. with transistors demonstrating three-terminal breakdown voltage up to 1400 V for 40 μm gate to drain spacing with static on resistance Ron = 32 mΩ cm2. On the other hand, a second series of HEMT structures with high aluminum content AlGaN barriers and sub-10 nm GaN channels have been grown perfectly strained with high sheet carrier densities allowing to preserve sheet resistances in the range of 880–1050 Ω/sq.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Chen Xiang, 陈翔, 邢艳辉 Xing Yanhui, 韩军 Han Jun, 李影智 Li Yingzhi, 邓旭光 Deng Xuguang, 范亚明 Fan Yaming, 张晓东 Zhang Xiaodong e 张宝顺 Zhang Baoshun. "Influence of AlN Interfacial Layer on Electrical Properties of AlGaN/AlN/GaN HEMT Materials Grown by MOCVD". Chinese Journal of Lasers 40, n. 6 (2013): 0606005. http://dx.doi.org/10.3788/cjl201340.0606005.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

ZHONG Lin-jian, 钟林健, 邢艳辉 XING Yan-hui, 韩军 HAN Jun, 陈翔 CHEN Xiang, 朱启发 ZHU Qi-fa, 范亚明 FAN Ya-ming, 邓旭光 DENG Xu-guang e 张宝顺 ZHANG Bao-shun. "Influence of Growth Time of AlN Interfacial Layer on Electrical Properties of AlGaN/AlN/GaN HEMT Materials". Chinese Journal of Luminescence 35, n. 7 (2014): 830–34. http://dx.doi.org/10.3788/fgxb20143507.0830.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Guo, Jingwei, Shengdong Hu, Ping Li, Jie Jiang, Ruoyu Wang, Yuan Wang e Hao Wu. "A Novel AlGaN/Si3N4 Compound Buffer Layer HEMT with Improved Breakdown Performances". Micromachines 13, n. 3 (18 marzo 2022): 464. http://dx.doi.org/10.3390/mi13030464.

Testo completo

Abstract (sommario):

In this article, an AlGaN and Si3N4 compound buffer layer high electron mobility transistor (HEMT) is proposed and analyzed through TCAD simulations. In the proposed HEMT, the Si3N4 insulating layer is partially buried between the AlGaN buffer layer and AlN nucleating layer, which introduces a high electric field from the vertical field plate into the internal buffer region of the device. The compound buffer layer can significantly increase the breakdown performance without sacrificing any dynamic characteristics and increasing the difficulty in the fabrication process. The significant structural parameters are optimized and analyzed. The simulation results reveal that the proposed HEMT with a 6 μm gate-drain distance shows an OFF-state breakdown voltage (BV) of 881 V and a specific ON-state resistance (Ron,sp) of 3.27 mΩ·cm2. When compared with the conventional field plate HEMT and drain connected field plate HEMT, the breakdown voltage could be increased by 148% and 94%, respectively.

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Taking, S., D. MacFarlane e E. Wasige. "AlN/GaN-Based MOS-HEMT Technology: Processing and Device Results". Active and Passive Electronic Components 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/821305.

Testo completo

Abstract (sommario):

Process development of AlN/GaN MOS-HEMTs is presented, along with issues and problems concerning the fabrication processes. The developed technology uses thermally grown Al2O3as a gate dielectric and surface passivation for devices. Significant improvement in device performance was observed using the following techniques: (1) Ohmic contact optimisation using Al wet etch prior to Ohmic metal deposition and (2) mesa sidewall passivation. DC and RF performance of the fabricated devices will be presented and discussed in this paper.

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Mukhopadhyay, Swarnav, Cheng Liu, Jiahao Chen, Md Tahmidul Alam, Surjava Sanyal, Ruixin Bai, Guangying Wang, Chirag Gupta e Shubhra S. Pasayat. "Crack-Free High-Composition (>35%) Thick-Barrier (>30 nm) AlGaN/AlN/GaN High-Electron-Mobility Transistor on Sapphire with Low Sheet Resistance (<250 Ω/□)". Crystals 13, n. 10 (30 settembre 2023): 1456. http://dx.doi.org/10.3390/cryst13101456.

Testo completo

Abstract (sommario):

In this article, a high-composition (>35%) thick-barrier (>30 nm) AlGaN/AlN/GaN high-electron-mobility transistor (HEMT) structure grown on a sapphire substrate with ultra-low sheet resistivity (<250 Ω/□) is reported. The optimization of growth conditions, such as reduced deposition rate, and the thickness optimization of different epitaxial layers allowed us to deposit a crack-free high-composition and thick AlGaN barrier layer HEMT structure. A significantly high two-dimensional electron gas (2DEG) density of 1.46 × 1013 cm−2 with a room-temperature mobility of 1710 cm2/V·s was obtained via Hall measurement using the Van der Pauw method. These state-of-the-art results show great potential for high-power Ga-polar HEMT design on sapphire substrates.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Wang, Cuimei, Xiaoliang Wang, Guoxin Hu, Junxi Wang, Hongling Xiao e Jianping Li. "The effect of AlN growth time on the electrical properties of Al0.38Ga0.62N/AlN/GaN HEMT structures". Journal of Crystal Growth 289, n. 2 (aprile 2006): 415–18. http://dx.doi.org/10.1016/j.jcrysgro.2005.11.118.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Shur, Michael, Grigory Simin, Kamal Hussain, Abdullah Mamun, M. V. S. Chandrashekhar e Asif Khan. "Quantum Channel Extreme Bandgap AlGaN HEMT". Micromachines 15, n. 11 (15 novembre 2024): 1384. http://dx.doi.org/10.3390/mi15111384.

Testo completo

Abstract (sommario):

An extreme bandgap Al0.64Ga0.36N quantum channel HEMT with Al0.87Ga0.13N top and back barriers, grown by MOCVD on a bulk AlN substrate, demonstrated a critical breakdown field of 11.37 MV/cm—higher than the 9.8 MV/cm expected for the channel’s Al0.64Ga0.36N material. We show that the fraction of this increase is due to the quantization of the 2D electron gas. The polarization field maintains electron quantization in the quantum channel even at low sheet densities, in contrast to conventional HEMT designs. An additional increase in the breakdown field is due to quantum-enabled real space transfer of energetic electrons into high-Al barrier layers in high electric fields. These results show the advantages of the quantum channel design for achieving record-high breakdown voltages and allowing for superior power HEMT devices.

Gli stili APA, Harvard, Vancouver, ISO e altri

36

AKPINAR, Ömer, Ahmet BİLGİLİ, Mustafa ÖZTÜRK e Süleyman ÖZÇELİK. "Optical Properties of AlInN/AlN HEMTs in Detail". Karadeniz Fen Bilimleri Dergisi 12, n. 2 (15 dicembre 2022): 521–29. http://dx.doi.org/10.31466/kfbd.954421.

Testo completo

Abstract (sommario):

In this study, the optical properties of AlInN/AlN high electron mobility transistor (HEMT) structure, grown on c-oriented sapphire with Metal-Organic Chemical Vapor Deposition (MOCVD) technique, being investigated. Optical characterization is made Kubelka- Munk method. Transmittance, absorbance, and reflectance are investigated in detail. Also, the Kubelka-Munk theory is employed to determine the forbidden energy band gap of InN by using special functions. The energy band gap obtained by this method was compared.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Zhang, Wenli, Zhengyang Liu, Fred Lee, Shuojie She, Xiucheng Huang e Qiang Li. "A Gallium Nitride-Based Power Module for Totem-Pole Bridgeless Power Factor Correction Rectifier". International Symposium on Microelectronics 2015, n. 1 (1 ottobre 2015): 000324–29. http://dx.doi.org/10.4071/isom-2015-wp11.

Testo completo

Abstract (sommario):

The totem-pole bridgeless power factor correction (PFC) rectifier has recently gained popularity for ac-dc power conversion. The emerging gallium nitride (GaN) high-electron-mobility transistor (HEMT), having a small body diode reverse recovery effect and low switching loss, is a promising device for use in the totem-pole approach. The design, fabrication, and thermal analysis of a GaN-based full-bridge multi-chip module (MCM) for totem-pole bridgeless PFC rectifier are introduced in this work. Four cascode GaN devices using the same pair of high-voltage GaN HEMT and low-voltage silicon (Si) power metal-oxide-semiconductor field-effect transistor (MOSFET) chips, as used in the discrete TO-220 package, were integrated onto one aluminum nitride direct-bonded-copper (AlN-DBC) substrate in a newly designed MCM. This integrated power module achieves the same function as four discrete devices mounted on the circuit board. In this module design, the Si and GaN bare die were arranged in a stack-die format for each cascode device to eliminate the critical common source inductance, and thus to reduce parasitic ringing at turn-off transients. In addition, an extra capacitor was added in parallel with the drain-source terminals of the Si MOSFET in each cascode GaN device to compensate for the mismatched junction capacitance between the Si MOSFET and GaN HEMT, which could accomplish the internal zero-voltage switching of the GaN device and reduce its turn-on loss. The AlN-DBC substrate and the flip-chip format were also applied in the module design. This GaN-based MCM shows an improved heat dissipation capability based on the thermal analysis and comparison with the discrete GaN device. The totem-pole bridgeless PFC rectifier built using this integrated power module is expected to have a peak efficiency of higher than 99% with a projected power density greater than 400 W/in3.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Михайлович, С. В., А. Ю. Павлов, К. Н. Томош e Ю. В. Федоров. "Низкоэнергетическое бездефектное сухое травление барьерного слоя HEMT AlGaN/AlN/GaN". Письма в журнал технической физики 44, n. 10 (2018): 61. http://dx.doi.org/10.21883/pjtf.2018.10.46100.17227.

Testo completo

Abstract (sommario):

AbstractA method of defectless dry etching of an AlGaN barrier layer is proposed, which consists in repeated plasmachemical oxidation of AlGaN and removal of the oxide layer by means of reactive ion etching in inductively coupled BCl_3 plasma. Using the proposed etching technology, AlGaN/AlN/GaN high-electron-mobility transistors (HEMTs) with a buried gate have been successfully fabricated for the first time. It is shown that the currents of obtained HEMTs are independent of the number of etching cycles, while the gate operating point shifts toward positive voltages up to obtaining transistors operating in the enhancement mode.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Koehler, Andrew D., Neeraj Nepal, Travis J. Anderson, Marko J. Tadjer, Karl D. Hobart, Charles R. Eddy e Francis J. Kub. "Atomic Layer Epitaxy AlN for Enhanced AlGaN/GaN HEMT Passivation". IEEE Electron Device Letters 34, n. 9 (settembre 2013): 1115–17. http://dx.doi.org/10.1109/led.2013.2274429.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Florovič, M., R. Szobolovszký, J. Kováč, J. Kováč, A. Chvála, J.-C. Jacquet e S. L. Delage. "Rigorous channel temperature analysis verified for InAlN/AlN/GaN HEMT". Semiconductor Science and Technology 34, n. 6 (21 maggio 2019): 065021. http://dx.doi.org/10.1088/1361-6641/ab1737.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Wang, Jie, Lingling Sun, Jun Liu e Mingzhu Zhou. "A surface-potential-based model for AlGaN/AlN/GaN HEMT". Journal of Semiconductors 34, n. 9 (settembre 2013): 094002. http://dx.doi.org/10.1088/1674-4926/34/9/094002.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Luo, Xin, Peng Cui, Tieying Zhang, Xinkun Yan, Siheng Chen, Liu Wang, Jiacheng Dai et al. "High performance of AlGaN/GaN HEMT with AlN cap layer". Micro and Nanostructures 198 (febbraio 2025): 208054. https://doi.org/10.1016/j.micrna.2024.208054.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Sidi Mohammed Hadj, Irid, Mohammed Khaouani, Imane Four, Zakarya KOURDI e Omar Azzoug. "SPSPT Switch Based AlN/GaN/AlGaN HEMT on Ku to Ku to V-Band for Satellite Application". Journal of Integrated Circuits and Systems 19, n. 3 (23 dicembre 2024): 1–4. https://doi.org/10.29292/jics.v19i3.885.

Testo completo

Abstract (sommario):

This paper details the design, fabrication, and characterization of a single-pole-single-throw (SPST) switch leveraging Aluminum Nitride/Gallium Nitride/Aluminum Gallium Nitride High Electron Mobility Transistor (AlN/GaN/AlGaN HEMT) technology specifically tailored for Ku to V-band satellite applications. The switch targets high-frequency operation within the 40 GHz to 75 GHz range to satisfy the demanding specifications of satellite communication systems. The design integrates AlN, GaN, and AlGaN layers to capitalize on the superior electrical properties of GaN-based transistors while guaranteeing robust isolation and performance enhancement through AlN and AlGaN integration. Design optimization focuses on achieving high isolation, minimal insertion loss and fast switching speeds - all primordial parameters for satellite communication links. Characterization simulations explore improvements in key metrics such as insertion loss, isolation, and switching time at V-band frequencies. In addition, the switch's performance is evaluated under varying temperature and radiation conditions to ensure reliability and suitability for space environments. Early findings suggest favorable performance attributes, hinting at the potential of the proposed SPSPT switch for V-band satellite applications, thereby contributing the progression of space-based RF technology.

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Mitterhuber, Lisa, René Hammer, Thomas Dengg e Jürgen Spitaler. "Thermal Characterization and Modelling of AlGaN-GaN Multilayer Structures for HEMT Applications". Energies 13, n. 9 (9 maggio 2020): 2363. http://dx.doi.org/10.3390/en13092363.

Testo completo

Abstract (sommario):

To optimize the thermal design of AlGaN-GaN high-electron-mobility transistors (HEMTs), which incorporate high power densities, an accurate prediction of the underlying thermal transport mechanisms is crucial. Here, a HEMT-structure (Al0.17Ga0.83N, GaN, Al0.32Ga0.68N and AlN on a Si substrate) was investigated using a time-domain thermoreflectance (TDTR) setup. The different scattering contributions were investigated in the framework of phonon transport models (Callaway, Holland and Born-von-Karman). The thermal conductivities of all layers were found to decrease with a temperature between 300 K and 773 K, due to Umklapp scattering. The measurement showed that the AlN and GaN thermal conductivities were a magnitude higher than the thermal conductivity of Al0.32Ga0.68N and Al0.17Ga0.83N due to defect scattering. The layer thicknesses of the HEMT structure are in the length scale of the phonon mean free path, causing a reduction of their intrinsic thermal conductivity. The size-effect of the cross-plane thermal conductivity was investigated, which showed that the phonon transport model is a critical factor. At 300 K, we obtained a thermal conductivity of (130 ± 38) Wm−1K−1 for the (167 ± 7) nm thick AlN, (220 ± 38) Wm−1K−1 for the (1065 ± 7) nm thick GaN, (11.2 ± 0.7) Wm−1K−1 for the (423 ± 5) nm thick Al0.32Ga0.68N, and (9.7 ± 0.6) Wm−1K−1 for the (65 ± 5) nm thick Al0.17Ga0.83N. Respectively, these conductivity values were found to be 24%, 90%, 28% and 16% of the bulk values, using the Born-von-Karman model together with the Hua–Minnich suppression function approach. The thermal interface conductance as extracted from the TDTR measurements was compared to results given by the diffuse mismatch model and the phonon radiation limit, suggesting contributions from inelastic phonon-scattering processes at the interface. The knowledge of the individual thermal transport mechanisms is essential for understanding the thermal characteristics of the HEMT, and it is useful for improving the thermal management of HEMTs and their reliability.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Huang, Chong-Rong, Hsien-Chin Chiu, Chia-Hao Liu, Hsiang-Chun Wang, Hsuan-Ling Kao, Chih-Tien Chen e Kuo-Jen Chang. "Characteristic Analysis of AlGaN/GaN HEMT with Composited Buffer Layer on High-Heat Dissipation Poly-AlN Substrates". Membranes 11, n. 11 (30 ottobre 2021): 848. http://dx.doi.org/10.3390/membranes11110848.

Testo completo

Abstract (sommario):

In this study, an AlGaN/GaN high-electron-mobility transistor (HEMT) was grown through metal organic chemical vapor deposition on a Qromis Substrate Technology (QST). The GaN on the QST device exhibited a superior heat dissipation performance to the GaN on a Si device because of the higher thermal conductivity of the QST substrate. Thermal imaging analysis indicated that the temperature variation of the GaN on the QST device was 4.5 °C and that of the GaN on the Si device was 9.2 °C at a drain-to-source current (IDS) of 300 mA/mm following 50 s of operation. Compared with the GaN HEMT on the Si device, the GaN on the QST device exhibited a lower IDS degradation at high temperatures (17.5% at 400 K). The QST substrate is suitable for employment in different temperature environments because of its high thermal stability.

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Khachariya, Dolar, Seiji Mita, Pramod Reddy, Saroj Dangi, J. Houston Dycus, Pegah Bagheri, M. Hayden Breckenridge et al. "Record >10 MV/cm mesa breakdown fields in Al_0.85Ga_0.15N/Al_0.6Ga_0.4N high electron mobility transistors on native AlN substrates". Applied Physics Letters 120, n. 17 (25 aprile 2022): 172106. http://dx.doi.org/10.1063/5.0083966.

Testo completo

Abstract (sommario):

The ultra-wide bandgap of Al-rich AlGaN is expected to support a significantly larger breakdown field compared to GaN, but the reported performance thus far has been limited by the use of foreign substrates. In this Letter, the material and electrical properties of Al0.85Ga0.15N/Al0.6Ga0.4N high electron mobility transistors (HEMT) grown on a 2-in. single crystal AlN substrate are investigated, and it is demonstrated that native AlN substrates unlock the potential for Al-rich AlGaN to sustain large fields in such devices. We further study how Ohmic contacts made directly to a Si-doped channel layer reduce the knee voltage and increase the output current density. High-quality AlGaN growth is confirmed via scanning transmission electron microscopy, which also reveals the absence of metal penetration at the Ohmic contact interface and is in contrast to established GaN HEMT technology. Two-terminal mesa breakdown characteristics with 1.3 μm separation possess a record-high breakdown field strength of ∼11.5 MV/cm for an undoped Al0.6Ga0.4N-channel layer. The breakdown voltages for three-terminal devices measured with gate-drain distances of 4 and 9 μm are 850 and 1500 V, respectively.

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Khachariya, Dolar, Seiji Mita, Pramod Reddy, Saroj Dangi, J. Houston Dycus, Pegah Bagheri, M. Hayden Breckenridge et al. "Record >10 MV/cm mesa breakdown fields in Al_0.85Ga_0.15N/Al_0.6Ga_0.4N high electron mobility transistors on native AlN substrates". Applied Physics Letters 120, n. 17 (25 aprile 2022): 172106. http://dx.doi.org/10.1063/5.0083966.

Testo completo

Abstract (sommario):

The ultra-wide bandgap of Al-rich AlGaN is expected to support a significantly larger breakdown field compared to GaN, but the reported performance thus far has been limited by the use of foreign substrates. In this Letter, the material and electrical properties of Al0.85Ga0.15N/Al0.6Ga0.4N high electron mobility transistors (HEMT) grown on a 2-in. single crystal AlN substrate are investigated, and it is demonstrated that native AlN substrates unlock the potential for Al-rich AlGaN to sustain large fields in such devices. We further study how Ohmic contacts made directly to a Si-doped channel layer reduce the knee voltage and increase the output current density. High-quality AlGaN growth is confirmed via scanning transmission electron microscopy, which also reveals the absence of metal penetration at the Ohmic contact interface and is in contrast to established GaN HEMT technology. Two-terminal mesa breakdown characteristics with 1.3 μm separation possess a record-high breakdown field strength of ∼11.5 MV/cm for an undoped Al0.6Ga0.4N-channel layer. The breakdown voltages for three-terminal devices measured with gate-drain distances of 4 and 9 μm are 850 and 1500 V, respectively.

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Khediri, Abdelkrim, Abbasia Talbi, Abdelatif Jaouad, Hassan Maher e Ali Soltani. "Impact of III-Nitride/Si Interface Preconditioning on Breakdown Voltage in GaN-on-Silicon HEMT". Micromachines 12, n. 11 (21 ottobre 2021): 1284. http://dx.doi.org/10.3390/mi12111284.

Testo completo

Abstract (sommario):

In this paper, an AIGaN/GaN metal-oxide-semiconductor high-electron-mobility transistor (MOS-HEMT) device is realized. The device shows normal ON characteristics with a maximum current of 570 mA/mm at a gate-to-source voltage of 3 V, an on-state resistance of 7.3 Ω·mm and breakdown voltage of 500 V. The device has been modeled using numerical simulations to reproduce output and transfer characteristics. We identify, via experimental results and TCAD simulations, the main physical mechanisms responsible for the premature breakdown. The contribution of the AlN/Silicon substrate interface to the premature off-state breakdown is pointed out. Vertical leakage in lateral GaN devices significantly contributes to the off-state breakdown at high blocking voltages. The parasitic current path leads to premature breakdown before the appearance of avalanche or dielectric breakdown. A comparative study between a MOS-HEMT GaN on a silicon substrate with and without a SiNx interlayer at the AlN/Silicon substrate interface is presented here. We show that it is possible to increase the breakdown voltages of the fabricated transistors on a silicon substrate using SiNx interlayer.

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Murugapandiyan, P., A. Mohanbabu, V. Rajya Lakshmi, V. N. Ramakrishnan, Arathy Varghese, MOHD Wasim, S. Baskaran, R. Saravana Kumar e V. Janakiraman. "Performance analysis of HfO2/InAlN/AlN/GaN HEMT with AlN buffer layer for high power microwave applications". Journal of Science: Advanced Materials and Devices 5, n. 2 (giugno 2020): 192–98. http://dx.doi.org/10.1016/j.jsamd.2020.04.007.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Ding, Rui, Weipeng Xuan, Shurong Dong, Biao Zhang, Feng Gao, Gang Liu, Zichao Zhang, Hao Jin e Jikui Luo. "The 3.4 GHz BAW RF Filter Based on Single Crystal AlN Resonator for 5G Application". Nanomaterials 12, n. 17 (5 settembre 2022): 3082. http://dx.doi.org/10.3390/nano12173082.

Testo completo

Abstract (sommario):

To meet the stringent requirements of 5G communication, we proposed a high-performance bulk acoustic wave (BAW) filter based on single crystal AlN piezoelectric films on a SiC substrate. The fabrication of the BAW filter is compatible with the GaN high electron mobility transistor (HEMT) process, enabling the implementation of the integration of the BAW device and high-performance monolithic microwave integrated circuit (MMIC). The single crystal AlN piezoelectric film with 650-nm thickness was epitaxially grown on the SiC substrate by Metal Organic Chemical Vapor Deposition (MOCVD). After wafer bonding and substrate removal, the single crystal AlN film with electrode layers was transferred to another SiC wafer to form an air gap type BAW. Testing results showed that the fabricated resonators have a maximum Q-factor up to 837 at 3.3 GHz resonant frequency and electromechanical coupling coefficient up to 7.2%. Ladder-type filters were developed to verify the capabilities of the BAW and process, which has a center frequency of 3.38 GHz with 160 MHz 3 dB bandwidth. The filter achieved a minimum 1.5 dB insertion loss and more than 31 dB out-of-band rejection. The high performance of the filters is attributed to the high crystallinity and low defects of epitaxial single crystal AlN films.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "HEMT AlN"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili