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Littérature scientifique sur le sujet « Plasma treatment, PECVD, plasma deposition, biocompatibility »
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Articles de revues sur le sujet "Plasma treatment, PECVD, plasma deposition, biocompatibility"
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Teske, Michael, Sabine Illner, Jana Markhoff, Niels Grabow et Stefan Oschatz. « Ultrathin fibre coatings on nanofibrous nonwovens by plasma enhanced chemical vapor deposition ». Current Directions in Biomedical Engineering 7, no 2 (1 octobre 2021) : 535–38. http://dx.doi.org/10.1515/cdbme-2021-2136.
Texte intégralRésumé :
Abstract For the generation of tailor-made polymer coatings on nanofibrous nonwovens plasma enhanced chemical vapor (PECVD) is a promising process, even for complex geometries. The plasma coatings can greatly improve their suitability for biomedical applications by optimising biocompatibility to the local needs, especially for cardiovascular disease treatments. Therein, wound healing and endothelialisation are important steps which are connected by a complex interaction. The monomers allylamine and hexamethyldisiloxane, as well as different process conditions were studied for the coating of nanofibrous thermoplastic silicone polycarbonate polyurethane (TSPCU) nonwovens. Aim of this study was to investigate the feasibility of plasma polymer coating under preservation of the nanofibrous morphological structure. Beside characterization of the nonwoven, biological evaluation with endothelial and fibroblast cells was performed. The prepared nonwoven samples support the feasibility of plasma coating under preservation of the nanofibrous structure. Also, different effects of the surfaces in contact with fibroblasts and endothelial cells could be observed.
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Terriza, Antonia, Jose I. Vilches-Pérez, Emilio de la Orden, Francisco Yubero, Juan L. Gonzalez-Caballero, Agustin R. González-Elipe, José Vilches et Mercedes Salido. « Osteoconductive Potential of Barrier NanoSiO2PLGA Membranes Functionalized by Plasma Enhanced Chemical Vapour Deposition ». BioMed Research International 2014 (2014) : 1–10. http://dx.doi.org/10.1155/2014/253590.
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The possibility of tailoring membrane surfaces with osteoconductive potential, in particular in biodegradable devices, to create modified biomaterials that stimulate osteoblast response should make them more suitable for clinical use, hopefully enhancing bone regeneration. Bioactive inorganic materials, such as silica, have been suggested to improve the bioactivity of synthetic biopolymers. An in vitro study on HOB human osteoblasts was performed to assess biocompatibility and bioactivity of SiO2functionalized poly(lactide-co-glycolide) (PLGA) membranes, prior to clinical use. A 15 nm SiO2layer was deposited by plasma enhanced chemical vapour deposition (PECVD), onto a resorbable PLGA membrane. Samples were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and infrared spectroscopy (FT-IR). HOB cells were seeded on sterilized test surfaces where cell morphology, spreading, actin cytoskeletal organization, and focal adhesion expression were assessed. As proved by the FT-IR analysis of samples, the deposition by PECVD of the SiO2onto the PLGA membrane did not alter the composition and other characteristics of the organic membrane. A temporal and spatial reorganization of cytoskeleton and focal adhesions and morphological changes in response to SiO2nanolayer were identified in our model. The novedous SiO2deposition method is compatible with the standard sterilization protocols and reveals as a valuable tool to increase bioactivity of resorbable PLGA membranes.
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Fares, Chaker, Randy Elhassani, Jessica Partain, Shu-Min Hsu, Valentin Craciun, Fan Ren et Josephine F. Esquivel-Upshaw. « Annealing and N2 Plasma Treatment to Minimize Corrosion of SiC-Coated Glass-Ceramics ». Materials 13, no 10 (21 mai 2020) : 2375. http://dx.doi.org/10.3390/ma13102375.
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To improve the chemical durability of SiC-based coatings on glass-ceramics, the effects of annealing and N2 plasma treatment were investigated. Fluorapatite glass-ceramic disks were coated with SiC via plasma-enhanced chemical vapor deposition (PECVD), treated with N2 plasma followed by an annealing step, characterized, and then immersed in a pH 10 buffer solution for 30 days to study coating delamination. Post-deposition annealing was found to densify the deposited SiC and lessen SiC delamination during the pH 10 immersion. When the SiC was treated with a N2 plasma for 10 min, the bulk properties of the SiC coating were not affected but surface pores were sealed, slightly improving the SiC’s chemical durability. By combining N2 plasma-treatment with a post-deposition annealing step, film delamination was reduced from 94% to 2.9% after immersion in a pH 10 solution for 30 days. X-ray Photoelectron spectroscopy (XPS) detected a higher concentration of oxygen on the surface of the plasma treated films, indicating a thin SiO2 layer was formed and could have assisted in pore sealing. In conclusion, post-deposition annealing and N2 plasma treatment where shown to significantly improve the chemical durability of PECVD deposited SiC films used as a coating for glass-ceramics.
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Cho, Cha et Kim. « Influence of Oxygen–Plasma Treatment on In-Situ SiN/AlGaN/GaN MOSHEMT with PECVD SiO2 Gate Insulator ». Materials 12, no 23 (29 novembre 2019) : 3968. http://dx.doi.org/10.3390/ma12233968.
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The influence of oxygen–plasma treatment on in situ SiN/AlGaN/GaN MOS high electron mobility transistor with SiO2 gate insulator was investigated. Oxygen–plasma treatment was performed on in situ SiN, before SiO2 gate insulator was deposited by plasma-enhanced chemical vapor deposition (PECVD). DC I-V characteristics were not changed by oxygen plasma treatment. However, pulsed I-V characteristics were improved, showing less dispersion compared to non-treated devices. During short-term gate bias stress, the threshold voltage shift was also smaller in a treated device than in an untreated one. X-ray photoemission spectroscopy also revealed that SiO2 on in situ SiN with oxygen–plasma treatment has an O/Si ratio close to the theoretical value. This suggests that the oxygen plasma treatment-modified surface condition of the SiN layer is favorable to SiO2 formation by PECVD.
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Enisherlova, Kira L., Lev A. Seidman, Ella M. Temper et Yuliy A. Kontsevoy. « Effect of PECVD SiNx deposition process parameters on electrical properties of SiNx/AlGaN/GaN structures ». Modern Electronic Materials 7, no 2 (30 juin 2021) : 63–71. http://dx.doi.org/10.3897/j.moem.7.2.73293.
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The effect of parameters of plasma enhanced chemical vapor deposition (PECVD) processes for SiNx film fabrication on the electrical parameters of dielectric/АlGaN/GaN structures has been studied. The effect of growing film composition, additional heterostructure surface treatment with nitrogen plasma before dielectric deposition and HF biasing during treatment on the parameters of the С–V and I–V curves of SiNx/АlGaN/GaN structures has been analyzed. We show that films with nitrogen to silicon concentration ratios of 60 and 40% and a high oxygen content exhibit a decrease in the positive fixed charge in the structures although the I–V curves of the structures exhibit current oscillations. Information has been reported on the effect of PECVD process mode on current oscillation parameters, e.g. period and amplitude, and length of I–V curve section in which oscillations occur. Possible explanation of these oscillations has been suggested. Additional nitrogen plasma treatment of heterostructure surface before monosilane supply to the chamber changes the magnitude and sign of fixed charge and reduces the free carrier concentration in the 2D gas channel of SiNx/АlGaN/GaN heterostructures. Experimental evidence has been provided for the effect of PECVD process parameters and surface preparation on the electrical parameters of the heterostructures grown.
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Baheti, Wufanbieke, Ming Xin Li, Fu Guo Wang, Jin Ge Song, Long Hua Xu et Bin Liu. « The Biocompatibility of Ti Alloy Improved by Nitrogen-Doped Diamond-Like Carbon Films ». Applied Mechanics and Materials 711 (décembre 2014) : 250–54. http://dx.doi.org/10.4028/www.scientific.net/amm.711.250.
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The nitrogen-doped diamond-like carbon film was prepared on Ti6Al4V alloy by using plasma enhanced chemical vapor deposition (PECVD) technique,and its biocompatibility was studied.The surface morphology,chemical composition and contact angle were measured by scanning electron microscope (SEM),X-ray photoelectron spectroscopy(XPS),Raman Spectrometer and contact angle measuring device. Finally, the proliferation rate and cellular morphology of 3T3-E1 osteoblast cells on different sample surfaces were tested and Image J software was used to statistically analyze the count of the adhered cells. The results showed that cell adhesion and proliferation were significantly (P<0.05) increased on nitrogen-doped diamond-like carbon films , which illustrated that N doping improved the biocompatibility of DLC films. This finding has potential clinical application value to modify titanium alloy for new bone formation.
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Lei, Jin Song, Yin Sheng Zou et Zhao Qiang Zhang. « Influence of p/i Interface Treatment on the Flexible Thin Film Solar Cells for Application in Building Integrated Photovoltaics ». Advanced Materials Research 287-290 (juillet 2011) : 1259–62. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1259.
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Nip type flexible a-Si solar cells for application in building integrated photovoltaics (BIPV) were deposited by plasma enhanced chemical vapor deposition (PECVD) method. In order to improve the efficiency and stability of the device, p-type microcrystalline silicon (μc-Si:H) film was used as the window layers. H plasma treatment was applied on the p/i interface and nucleation layer was introduced to enhance the deposition of p-type μc-Si:H film on the surface of a-Si:H. Results suggest that with the application of H plasma treatment and the nucleation layer introduction, high quality p-type μc-Si:H film and high efficiency flexible solar cells were obtained.
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Zarchi, Meysam, Sharokh Ahangarani et Maryam Zare Sanjari. « The role of PECVD hard coatings on the performance of industrial tools ». Metallurgical and Materials Engineering 20, no 1 (31 mars 2014) : 15–22. http://dx.doi.org/10.5937/metmateng1401015z.
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The advantages of the application of hard coatings, which are well knownfor cutting tools, are to a much lesser extent explored for casting, extrusion, molding and forming tools. Increasing the lifetime of these tools is an important task in surface engineering because of complex loading conditionsand often complicated tool geometry. The plasma-enhanced chemical vapor deposition (PECVD) technique is well suited to deposit hard coatings onto large dies and moulds. The aim of this study was to discuss deposition processes suitable for coating of the often large three-dimensional molds and dies used in metal forming. Furthermore, results obtained using different hard coatings in industrial applications for several case studies like aluminum pressure die-casting; plastics injection molding and sheet metal forming are presented and discussed. For best coating performance, a careful optimization of both substrate pretreatment and coating deposition is necessary. The plasma-enhanced chemical vapor deposition (PECVD) technique shows advantages for these applications because of the high flexibility in pre-treatment using chemical etching and plasma-nitriding, because of its ability to coat large complexly shaped tools and because of the possibility of deposition of low-chlorine containing low-friction coatings.
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Tatoulian, Michael, Enrico Gallino, R. Jafari, Farzaneh Arefi-Khonsari, L. Tatoulian, Jean Pascal Borra, François Lewis et D. Mantovani. « Plasma and Electrospray Deposition to Improve the Biocompatibility of Stents ». Materials Science Forum 539-543 (mars 2007) : 529–34. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.529.
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Metallic Intravascular stents are medical devices used to scaffold a biological lumen, mostly diseased arteries, after balloon angioplasty. They are commonly made of 316L stainless steel or Nitinol, two alloys containing Nickel, an element classified as potentially toxic and carcinogenic. Although they are largely implanted, the long-term safety of such metallic elements is still controversial, since the corrosion processes may lead to the release of several metallic ions. In order to avoid the metallic ion release in the body and to improve the biocompatibility of metallic stents with their biological environments, polymer coatings have been deposited by two different technologies, i.e. plasma surface modifications and Electrospraying. The role of the polymer coating is then to encapsulate the stainless steel device, and to favour the chemical grafting of Phosphorylcholine, a molecule known for its hemocompatible properties.1 In this talk, the state of the art on low pressure and atmospheric pressure plasmas for deposition of organic coatings will be given and we will present the advantages and drawbacks of each process. Then, we will present an original technology that combine a Dielectric Barrier Discharge and an electrospraying system to deposit well-defined Polyacrylic acid and Polyallylamine films. The advantage of such system is the possibility to limit the extent of the monomer fragmentation and to give rise to rapid deposition of a highly functionalised plasma polymer layer, and also the possibility to cover three dimensional objects, such as stents. Thus, the theory of EHDA technology will be explained: special attention has been paid to define the Electrospray parameters (Voltage, flow of precursor, nozzle-substrate distance…) which control the size distribution of the charged droplets and as a consequence, the structure of the film coating. The film coatings have been analysed with XPS and by ATR. Moreover, special attention will be paid on the stability of the coating which is related to both spraying conditions as well as to the preliminary plasma treatment. The potentiality and the features of the EHDA process will be then presented.
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JIANG, JIN, et SUK JAE CHUNG. « HYDROGEN-FREE DIAMOND-LIKE CARBON DEPOSITED BY A LAYER-BY-LAYER TECHNIQUE USING PECVD ». International Journal of Modern Physics B 14, no 02n03 (30 janvier 2000) : 154–66. http://dx.doi.org/10.1142/s0217979200000157.
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We developed a hydrogen-free diamond like carbon (DLC) film by a novel deposition technique of a layer-by-layer technique using plasma enhanced chemical vapor deposition (PECVD) in which a repeated deposition of a thin DLC layer and subsequently CF 4 plasma treatment on its surface have been carried out. The electrical, optical and structural properties of the DLC films deposited depend on the CF 4 plasma exposure time. The hydrogen content is less than 1 at % when the CF4 plasma exposure time is 140s. Its emission current is much higher and stability is much improved compared with conventional DLC.N-type, hydrogen-free DLC could be obtained by N ion doping N2 gas-phase doping in the CF 4 plasma. The optimum [ N 2][ CH 4] flow rate was found to be 9% for the efficient electron emission, at which the onset-field was 7.2 V /μ. The nitrogen gas-phase doped hydrogen-free DLC coating on Mo tip field emitter arrays (FEAs) increased the electron emission current from 160μ A to 1.52 mA and improved the stability in electron emission current.
Thèses sur le sujet "Plasma treatment, PECVD, plasma deposition, biocompatibility"
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ZIANO, ROBERTO. « Plasma treatment for biomedical application on polymeric substrate ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/7774.
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This work arises from the possibility of changing the surface properties of materials with the use of plasma. It proved to be a very good method for treating surfaces, it is in fact able to modify surface properties of materials without altering their bulk properties. In particular, with the Plasma
Enhanced Chemical Vapour Deposition (PECVD) is feasible sustaining the polymerization of a specific monomer depositing thin films containing interesting chemical groups. For these reasons, this technique was chosen for modifying polypropylene substrates through the polymerization of acrylic acid, an organic acid carrying the carboxy group (COOH). This chemical group is of particular interest because it has biocompatibility properties itself and can be used for a further grafting reaction allowing further surface modifications.
During this works two types of plasma reactor were optimized for obtaining the best working condition, namely, creating a stable coating of poly-acrylic acid resistant to Phosphate Buffer Saline
(PBS) and water washing.
The physical and chemical properties of the deposited thin films were studied by means of Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR), Water Contact Angle (WCA), XRay Photoelectron Spectroscopy (XPS), Atomic Force Microscope (AFM). The density of COOH groups into the polypropylene surface were evaluated by ion-exchange reaction with Thionin
Acetate (THA).
A simple model for explaining the particular physical composition and stratification of the films is presented along with a computer simulation.
The reactor geometry effect onto the film properties was investigated.
Furthermore, some applications of the process were then discussed.
Part of the present work consisted in the use of the AFM for internal scopes and extramural collaborations. Among these, the measurement of the thickness of different PEG chains bounded to the plasma treated surface in support of Monte Carlo simulations of their polymer dynamics.
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Zhou, Ming. « Novel photocatalytic TiO2-based porous membranes prepared by plasma-enhanced chemical vapor deposition (PECVD) for organic pollutant degradation in water ». Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS090/document.
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Le dépôt chimique en phase vapeur assisté par plasma est appliqué pour préparer des couches minces amorphes de TiO2 à basse température. Un recuit à 300 °C pendant un temps minimum de 4,5 h permet de former la phase cristalline anatase. Les principales caractéristiques de ces couches minces comme leur structure cristalline, leur microstructure, leur largeur de bande interdite et leur hydrophilie de surface, sont déterminées. Leurs performances fonctionnelles comme photocatalyseurs sont d'abord examinées selon le test breveté par Pilkington, consistant à éliminer sous irradiation UV de l'acide stéarique préalablement adsorbé sur les couches de TiO2 ici déposées sur des plaquettes de silicium. Des membranes M100 (couche continue de TiO2) et M800 (couche de TiO2 couvrant les grains de support) sont préparées sur les couches de surface macroporeuses de supports poreux en alumine, de tailles moyennes de pores respectives, 100 nm et 800 nm. Ces membranes sont testées en condition "statique", avec la diffusion d'un soluté organique dilué dans l'eau. Pour le bleu de méthylène, on montre que la quantité de composé détruit par unité de surface de membrane et par unité de temps est égale à 2 × 10-8 mol m-2 s-1 pour la membrane M100 et 1 × 10-8 mol m-2 s- 1 pour la membrane M800. Ces membranes sont également testées dans des conditions "dynamiques", à savoir en procédé baromembranaire, avec deux configurations différentes (couche photocatalytique du côté de l'alimentation ou du côté du perméat) et trois composés organiques différents (bleu de méthylène, acide orange 7 et phénol). La modélisation du procédé (adsorption et réaction photocatalytique) est finalement réalisée à partir des données expérimentales disponiblesPlasma-enhanced chemical vapor deposition is applied to prepare amorphous TiO2 thin films at low temperature. Post-annealing at 300 °C for minimal staying time 4.5 h is required to form crystalline anatase phase. Characteristics of the TiO2 thin films including crystalline structure, microstructure, band gap and surface hydrophilicity, are determined. Functional performance of these anatase thin films as photocatalysts is first examined with patented Pilkington assessment by removing, under UV irradiation, stearic acid initially adsorbed on TiO2 layers here deposited on silicon wafers. Membranes M100 (TiO2 continuous layer) and M800 (TiO2-skin on support grain) are prepared on the macroporous top layer of porous alumina supports with an average pore size of 100 nm and 800 nm, respectively. These membranes are tested in “static” condition under the effect of diffusion of an organic solute in water. For Methylene Blue it is shown that the quantity of destroyed compound per unit of membrane surface area and per unit of time is equal to 2×10−8 mol m-2 s-1 for M100 and 1×10−8 mol m-2 s-1 for M800. These membranes are also tested in “dynamic” conditions, i.e. pressure-driven membrane processes, with two different configurations (photocatalytic layer on the feed side or on the permeate side) and three different organics (Methylene Blue, Acid Orange 7 and phenol). Process modelling (adsorption and photocatalysis reaction) is finally carried out from the available experimental outputs
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Jehanathan, Neerushana. « Thermal stability of plasma enhanced chemical vapor deposited silicon nitride thin films ». University of Western Australia. School of Mechanical Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0069.
Texte intégralRésumé :
[Truncated abstract] This study investigates the thermal stability of Plasma Enhanced Chemical Vapor Deposited (PECVD) silicon nitride thin films. Effects of heat-treatment in air on the chemical composition, atomic bonding structure, crystallinity, mechanical properties, morphological and physical integrity are investigated. The chemical composition, bonding structures and crystallinity are studied by means of X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FTIR) Spectroscopy and Transmission Electron Microscopy (TEM). The mechanical properties, such as hardness and Young’s modulus, are determined by means of nanoindentation. The morphological and physical integrity are analyzed using Scanning Electron Microscopy (SEM) . . . The Young’s modulus (E) and hardness (H) of the film deposited at 448 K were measured to have E=121±1.8 GPa and H=11.7±0.25 GPa. The film deposited at 573 K has E=150±3.6 GPa and H=14.7±0.6 GPa. For the film deposited at 573 K, the Young’s modulus is not affected by heating up to 1148 K. Heating at 1373 K caused significant increase in Young’s modulus to 180∼199 GPa. This is attributed to the crystallization of the film. For the film deposited at 448 K, the Young’s modulus showed a moderate increase, by ∼10%, after heating to above 673 K. This is consistent with the much lower level of crystallization in this film as compared to the film deposited at 573 K. In summary, low temperature deposited PECVD SiNx films are chemically and structurally unstable when heated in air to above 673 K. The main changes include oxidation to SiO2, crystallization of Si3N4 and physical cracking. The film deposited at 573 K is more stable and damage and oxidation resistant than the film deposited at 448 K.
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PEKÁREK, Michal. « Optimalizace depozičních parametrů za účelem vytvoření fotokatalytických titanoxidových vrstev metodou PECVD ». Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-153375.
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This thesis presents Photocatalytic TiOx layers created by own PECVD reactor assembled in the building of Department of Applied Physics and Technics. Parameters of depositions were optimalized as well as the PECVD reactor itself. Final layers are compared to layers made by Degussa P25. As a result based on the included measurements, this thesis tries to answer the question whether PECVD is the suitable method for depositions of photocatalytic layers.
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Huang, Man-Chi, et 黃曼琦. « The Efficiency Improvement Study of Heterojunction with Intrinsic Thin Layer (HIT) Solar Cell Deposition by 40.68MHz VHF-PECVD System using Rapid Thermal Annealing (RTA) and Post H2 Plasma Treatment ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/75599433162136893466.
Texte intégralRésumé :
碩士國立交通大學
材料科學與工程學系
101
In this work, we studied on how to use post hydrogen (H2) plasma treatment and RTA treatment to improve HIT solar cell performance. First, we adjusted the Si thin film deposition parameters, and optimized HIT solar cell characteristics. Then, we used device simulation software (AMPS-1D) to find out the optimized device structure. In these experiments, we tried to adjust the post hydrogen (H2) plasma treatment condition, such as H2 flux, plasma power, pressure and post H2 plasma treatment time to find the optimization deposition conditions. The dark IV result indicated that a low plasma power (100W), a low ambient pressure (0.75torr), and longer post H2 plasma treatment time (50 sec) is a preferable condition to enhance the HIT solar cell performance. In the solar cell photo IV measurement, when the post H2 plasma treatment was applied on HIT solar cell, a short circuit current density (Jsc) was improved around 5.2 % (from 13.92 mA/cm2 to 14.68 mA/cm2) and an 18.9 % increased fill-factor (F. F.) were observed (from 49.5 to 61.0). Voc was increased significantly about 16.7 % (from 0.75 V to 0.90 V). Besides, the overall efficiency increased around 35.8 % was also achieved (from 5.17 % to 8.05 %). In addition, we tried to use the rapid thermal annealing (RTA) treatment to improve HIT solar cell performance. We used different RTA parameters, and found the best device characteristics under RTA temperature about 200℃. In these series of solar cell photo IV measurement, when the RTA treatment was used on HIT solar cell, a short circuit current density (Jsc) was improved around 15.4 % (from 14.68 mA/cm2 to 17.36 mA/cm2) and an 13 % increased fill-factor (F. F.) were observed (from 61.0 to 70.1 ). Voc was increased about 1.1 % (from 0.90 V to 0.91 V). Besides, the overall efficiency increased around 27.3 % was also achieved (from 8.05 % to 11.07 % ).
Actes de conférences sur le sujet "Plasma treatment, PECVD, plasma deposition, biocompatibility"
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Eremeev, Anatoly, Sergei Egorov et Vladislav Kholoptsev. « MILLIMETER WAVE ABSORPTION IN HYDROXYAPATITE AND 3YSZ CERAMICS IN WIDE TEMPERATURE RANGE ». Dans Ampere 2019. Valencia : Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9754.
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In the field of ceramic-based materials processing the last three decades has been marked by significant academic and industry interest in Additive Manufacturing (AM) technology due to its capability to produce ceramic parts with complex geometry and customizable materials properties. Conceptually, AM technology is a layer-by-layer fabrication of three dimensional physical parts directly from computer-aided design [1]. Solidification of the parts prepared from substances containing ceramic powder may be performed either by conventional heat treatment of a part as whole or by directed energy deposition. Both these strategies can be implemented using gyrotron-based millimeter-wave facilities allowing alternatively both the uniform heating of large-size parts in multi-mode cavities and local heating by focused wave-beams [2]. Hydroxyapatite- and yttria-stabilized zirconia-based ceramics are widely used in biomedical applications due to their high biocompatibility. The knowledge of their microwave absorption variation with temperature and porosity as the materials are densified, is necessary to optimize the scheme of microwave heating. 8 mm diameter disks for the measurements were prepared by uniaxial compacting from commercially available hydroxyapatite (HA) powder and yttria-stabilized zirconia (3YSZ) powder (Tosoh corp.). The measurements were performed at 24 GHz 3 kW gyrotron system. Samples for measurements were placed into the gyrotron system applicator and surrounded with porous alumina based thermal insulation. The design of the applicator and insulation allowed performing optical measurements of both the sample size and temperature distribution over the surface of the sample using a digital monochrome CCD camera. Measurements were made by the calorimetric method, when the microwave power absorbed in the sample is determined basing on the difference of the heating/cooling rates at the moments of intentional abrupt change of the microwave power at different sample temperatures. Absorption coefficient was determined as a division of the absorbed power to the incident microwave power. Special calibration experiments were made for determining microwave power density in the applicator and inside the thermal insulation. The method allows to measure absorption coefficients in situ during the sintering process. Absorption coefficients of HA were obtained in the range of 200 C - 1200 C, and for 3YSZ - in the range of 400 C - 1400 C both in situ during sintering and for as sintered samples. Dependencies of the absorption coefficients on the temperature and porosity are discussed. References Vaezi, M., et al., Int. J. Adv. Manuf. Technol., 2013, 67, 1721–1759. Bykov, Yu., Eremeev, A., et al., IEEE Trans. Plasma Science, 2004, 32, 67–72.