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    GaN-based Metal-Oxide-Semiconductor Devices

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    AlGaN/GaN ์ „๋ ฅ์†Œ์ž์˜ ํŠน์„ฑ ํ–ฅ์ƒ์„ ์œ„ํ•œ ์‹๊ฐ๊ณผ ์ ˆ์—ฐ๋ง‰์— ๊ด€ํ•œ ์—ฐ๊ตฌ

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    ํ•™์œ„๋…ผ๋ฌธ (๋ฐ•์‚ฌ) -- ์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› : ๊ณต๊ณผ๋Œ€ํ•™ ์ „๊ธฐยท์ •๋ณด๊ณตํ•™๋ถ€, 2020. 8. ์„œ๊ด‘์„.์ตœ๊ทผ ์—๋„ˆ์ง€ ์œ„๊ธฐ์™€ ํ™˜๊ฒฝ๊ทœ์ œ ๊ฐ•ํ™”, ์นœํ™˜๊ฒฝ ๋…น์ƒ‰์„ฑ์žฅ ๋“ฑ์˜ ์ด์Šˆ๊ฐ€ ๋Œ€๋‘๋˜์–ด ์—๋„ˆ์ง€ ์ ˆ๊ฐ๊ณผ ํ™˜๊ฒฝ ๋ณดํ˜ธ ๋ถ„์•ผ์— IT ๊ธฐ์ˆ ์„ ์ ‘๋ชฉ, ํ™œ์šฉํ•˜๋Š” ๊ทธ๋ฆฐ IT ํŒจ๋Ÿฌ๋‹ค์ž„์ด ๋ถ€๊ฐ๋˜๊ณ  ์žˆ๋‹ค. ํ˜„์žฌ ๊ณ ์œ ๊ฐ€ ํ™˜๊ฒฝ๊ทœ์ œ ๊ฐ•ํ™”์— ๋Œ€์‘ํ•˜๊ธฐ ์œ„ํ•ด ํ•˜์ด๋ธŒ๋ฆฌ๋“œ ์ž๋™์ฐจ, ์ „๊ธฐ์ž๋™์ฐจ ๋“ฑ ์นœํ™˜๊ฒฝ ๋ฏธ๋ž˜ํ˜• ์ž๋™์ฐจ ๊ฐœ๋ฐœ์ด ์š”๊ตฌ๋˜๊ณ  ์žˆ์œผ๋ฉฐ, ์ž๋™์ฐจ์—์„œ ์ „์žฅ๋ถ€ํ’ˆ์ด ์ฐจ์ง€ํ•˜๋Š” ์›๊ฐ€๋น„์ค‘์€ ์•ฝ 40%๊นŒ์ง€ ๋‹ฌํ•  ๊ฒƒ์œผ๋กœ ์ „๋ง๋˜๊ณ  ์ด ์ค‘ ๋ฐ˜๋„์ฒด๊ฐ€ ์ฐจ์ง€ํ•˜๋Š” ๋น„์šฉ์€ ์•ฝ 30% ์ •๋„๋กœ ์ถ”์ •๋œ๋‹ค. ์ด๋Ÿฌํ•œ ์ž๋™์ฐจ ์ „์žฅ๋ถ€ํ’ˆ์—์„œ ์ „๋ ฅ์†Œ์ž๊ฐ€ ํ•ต์‹ฌ๋ถ€ํ’ˆ์œผ๋กœ ์ž๋ฆฌ ์žก์„ ์ „๋ง์ด๋‹ค. ์ง€๊ธˆ๊นŒ์ง€๋Š” ์‹ค๋ฆฌ์ฝ˜ ๊ธฐ๋ฐ˜์˜ ์ „๋ ฅ์†Œ์ž ๊ธฐ์ˆ ์ด ์ „๋ ฅ๋ฐ˜๋„์ฒด ์‹œ์žฅ์˜ ๋Œ€๋ถ€๋ถ„์„ ์ฃผ๋„ํ•˜๊ณ  ์žˆ์ง€๋งŒ ์ „๋ ฅ๊ธฐ๊ธฐ ๋กœ๋“œ๋งต์— ์˜ํ•˜๋ฉด ์ „๋ ฅ๋ฐ€๋„๊ฐ€ ํ•ด๋ฅผ ๊ฑฐ๋“ญํ•˜๋ฉด์„œ ์ง€์†์ ์œผ๋กœ ์ฆ๊ฐ€ํ•˜๊ธฐ ๋•Œ๋ฌธ์— ๋‚ด์—ด, ๋‚ด์••, ์ „๋ ฅ์†์‹ค, ์ „๋ ฅ๋ฐ€๋„ ๋“ฑ์—์„œ ๋‚˜ํƒ€๋‚˜๋Š” ๋งŽ์€ ํ•œ๊ณ„๋ฅผ ๊ฐ€์ง€๊ณ  ์žˆ๋Š” ํ˜„์žฌ์˜ ์‹ค๋ฆฌ์ฝ˜ ๊ธฐ๋ฐ˜ ์ „๋ ฅ์‹œ์Šคํ…œ์€ ํšจ์œจ์ด ๋ˆˆ์— ๋„๊ฒŒ ๊ฐ์†Œํ•  ๊ฒƒ์ด ์ž๋ช…ํ•˜๋ฏ€๋กœ ์ „๋ ฅ์‹œ์Šคํ…œ์˜ ์ „๋ ฅ์ „์†กํšจ์œจ๊ณผ ์‹ ๋ขฐ์„ฑ์˜ ์ค‘์š”์„ฑ์ด ํฌ๊ฒŒ ๋Œ€๋‘๋˜๊ณ  ์žˆ๋‹ค. ์ด ๊ฐ™์€ ์‚ฌํšŒ์  ์š”๊ตฌ๋กœ ๋ณผ ๋•Œ ํ˜„์žฌ์˜ ์‹ค๋ฆฌ์ฝ˜ ์ „๋ ฅ์†Œ์ž์˜ ๊ธฐ์ˆ ์  ํ•œ๊ณ„๋ฅผ ๋›ฐ์–ด๋„˜๋Š” ๊ณ ํšจ์œจ์˜ ์ฐจ์„ธ๋Œ€ ์ „๋ ฅ๋ฐ˜๋„์ฒด ์†Œ์ž์˜ ๊ฐœ๋ฐœ์ด ์‹œ๊ธ‰ํžˆ ์š”๊ตฌ๋˜๋ฉฐ SiC์™€ GaN์™€ ๊ฐ™์€ ๊ด‘๋Œ€์—ญ ๋ฐ˜๋„์ฒด๊ฐ€ ์ฐจ์„ธ๋Œ€ ์ „๋ ฅ๋ฐ˜๋„์ฒด ์†Œ์žฌ๋กœ ์œ ๋ ฅํ•ด์ง€๊ณ  ์žˆ๋‹ค. ๋˜ํ•œ ์ „๋ ฅ์‹œ์Šคํ…œ์—์„œ๋Š” ์‹œ์Šคํ…œ์˜ ์•ˆ์ „์„ฑ๊ณผ ํšŒ๋กœ์˜ ๊ฐ„๋žตํ™”๋ฅผ ์œ„ํ•˜์—ฌ normally-off (์ฆ๊ฐ•ํ˜•) ์ „๋ ฅ์†Œ์ž๊ฐ€ ์š”๊ตฌ๋˜๊ธฐ ๋•Œ๋ฌธ์— normally-off (์ฆ๊ฐ•ํ˜•) GaN ์ „๋ ฅ์†Œ์ž์— ๋Œ€ํ•œ ๊ฐœ๋ฐœ์ด ํ•„์ˆ˜์ ์ด๋‹ค. ๋ณธ ๊ทธ๋ฃน์—์„œ๋Š” gate-recess ๊ณต์ •์„ ์ด์šฉํ•˜์—ฌ normally-off ๋™์ž‘์„ ์‹คํ˜„ํ•˜๋Š” ์—ฐ๊ตฌ๋ฅผ ์ง„ํ–‰ํ•˜์˜€๊ณ , gate-recess ์‹œ ๋ฐœ์ƒํ•˜๋Š” ์‹๊ฐ ๋ฐ๋ฏธ์ง€๋ฅผ ์ค„์ด๊ณ  ์šฐ์ˆ˜ํ•œ ์„ฑ๋Šฅ์˜ ๊ฒŒ์ดํŠธ ์ ˆ์—ฐ๋ง‰์„ ๊ฐœ๋ฐœํ•˜์—ฌ GaN ์ „๋ ฅ ๋ฐ˜๋„์ฒด ์†Œ์ž์˜ ์ „๊ธฐ์  ํŠน์„ฑ ๋ฐ ์‹ ๋ขฐ์„ฑ์„ ๊ฐœ์„ ํ•˜๋Š” ์—ฐ๊ตฌ๋ฅผ ์ง„ํ–‰ํ•˜์˜€๋‹ค. ์‹๊ฐ ์—ฐ๊ตฌ์—์„œ๋Š” ์ตœ์ข…์ ์œผ๋กœ ์…€ํ”„ DC ๋ฐ”์ด์–ด์Šค๊ฐ€ ๋‚ฎ์€ O2, BCl3 ํ”Œ๋ผ์ฆˆ๋งˆ๋ฅผ ์ด์šฉํ•œ atomic layer etching์„ ๊ฐœ๋ฐœํ•˜์˜€๊ณ , ์ด๋ฅผ ํ†ตํ•ด ๊ฑฐ์น ๊ธฐ๊ฐ€ ์ž‘๊ณ  ํ‘œ๋ฉด N vacancy๊ฐ€ ์ ์€ ๊ณ ํ’ˆ์งˆ์˜ (Al)GaN ํ‘œ๋ฉด์„ ์–ป์„ ์ˆ˜ ์žˆ์—ˆ๋‹ค. ๋ฐ•๋ง‰ ์—ฐ๊ตฌ์—์„œ๋Š” Oxide ๋ฐ•๋ง‰ ์ฆ์ฐฉ ์‹œ, (Al)GaN ํ‘œ๋ฉด์— ์ƒ์„ฑ๋˜์–ด ๊ณ„๋ฉด ํŠน์„ฑ์„ ์•…ํ™”์‹œํ‚ค๋Š” Ga2O3 ์ƒ์„ฑ์„ ๋ง‰๊ธฐ์œ„ํ•ด ALD AlN layer๋ฅผ ๊ฐœ๋ฐœ ๋ฐ ์ ์šฉํ•˜์—ฌ ๋ฐ•๋ง‰/(Al)GaN ๊ณ„๋ฉด ํŠน์„ฑ์„ ํ–ฅ์ƒ์‹œ์ผฐ๋‹ค. ์ด๋กœ ์ธํ•ด ์†Œ์ž์˜ ๋™์ž‘์ „๋ฅ˜ ์ฆ๊ฐ€ ๋ฐ Dit ๊ฐ์†Œ ๊ฒฐ๊ณผ๋ฅผ ์–ป์„ ์ˆ˜ ์žˆ์—ˆ๊ณ  ์ŠคํŠธ๋ ˆ์Šค์— ๋”ฐ๋ฅธ ๋ฌธํ„ฑ์ „์•• ์ด๋™ ํŠน์„ฑ์˜ ๊ฐ์†Œ๋กœ ์†Œ์ž์˜ ์‹ ๋ขฐ์„ฑ ๋˜ํ•œ ๊ฐœ์„ ์‹œํ‚ฌ ์ˆ˜ ์žˆ์—ˆ๋‹ค. ์ด๋Š” ํƒ€ ๊ธฐ๊ด€์˜ ๊ฒฐ๊ณผ์™€ ๋น„๊ตํ•ด๋„ ๋’ค๋–จ์–ด์ง€์ง€ ์•Š๋Š” ์šฐ์ˆ˜ํ•œ ํŠน์„ฑ์„ ๋ณด์—ฌ์ฃผ์—ˆ๋‹ค. ๊ฒฐ๋ก ์ ์œผ๋กœ ๋ณธ ์—ฐ๊ตฌ์˜ ์ž‘์€ ํ”Œ๋ผ์ฆˆ๋งˆ ๋ฐ๋ฏธ์ง€๋ฅผ ๊ฐ–๋Š” ์‹๊ฐ๊ณต์ •๊ณผ ๊ณ ํ’ˆ์งˆ ์ ˆ์—ฐ๋ง‰ ๊ฐœ๋ฐœ์„ ํ†ตํ•ด ์šฐ์ˆ˜ํ•œ ํŠน์„ฑ์˜ GaN ์ „๋ ฅ์†Œ์ž๋ฅผ ๊ตฌํ˜„ํ•  ์ˆ˜ ์žˆ์—ˆ๊ณ  ํ–ฅํ›„ ์ฐจ์„ธ๋Œ€ ์ „๋ ฅ์†Œ์ž์— ์ ์šฉ์„ ์œ„ํ•œ ๊ฐ€๋Šฅ์„ฑ์„ ํ™•๋ณดํ•˜์˜€๋‹ค.The Si technology for power devices have already approached its theoretical limitations due to its physical and material properties, despite the considerable efforts such as super junction MOSFET, trench gate, and insulated gate bipolar transistors. To overcome these limitations, many kinds of compound materials such as GaN, GaAs, SiC, Diamond and InP which have larger breakdown voltage and high electron velocity than Si also have been studied as future power devices. GaN has been considered as a breakthrough in power applications due to its high critical electric field, high saturation velocity and high electron mobility compared to Si, GaAs, and SiC. Especially, AlGaN/GaN heterostructure field-effect transistors (HFETs) have been considered as promising candidates for high power and high voltage applications. However, these AlGaN/GaN heterostructure field-effect transistors with the 2DEG are naturally normally-on, which makes the devices difficult to deplete the channel at zero gate bias. Among the various methods for normally-off operation of GaN devices, gate-recess method is a promising method because it can be easier to implement than other approaches and ensure normally-off operation. However, charge trapping at the interface between gate dielectric and (Al)GaN and in the gate dielectric is a big issue for recessed gate MIS-HEMTs. This problem leads to degradation of channel mobility, on-resistance and on-current of the devices. Especially, Vth hysteresis after a positive gate voltage sweep and Vth shift under a gate bias stress are important reliability challenges in gate recessed MIS-HEMTs. The scope of this work is mainly oriented to achieve high quality interface at dielectric/(Al)GaN MIS by studying low damage etching methods and the ALD process of various dielectric layers. In the etching study, various etching methods for normally-off operation have been studied. Also, etching damage was evaluated by various methods such as atomic force microscopy (AFM), photoluminescence (PL) measurements, X-ray photoelectron spectroscopy (XPS) measurements and electrical properties of the recessed schottky devices. Among the etching methods, the ALE shows the smoothest etched surface, the highest PL intensity and N/(Al+Ga) ratio of the etched AlGaN surface and the lowest leakage current of the gate recessed schottky devices. It is suggested that the ALE is a promising etching technique for normally-off gate recessed AlGaN/GaN MIS-FETs. In the study of dielectrics, excellent electrical characteristics and small threshold voltยฌage drift under positive gate bias stress are achieved by employing the SiON interfacial layer. However, considerable threshold voltage drift is observed under the higher positive gate bias stress even at the devices using the SiON interfacial layer. For further improvement of interface and reliability of devices, we develop and optimize an ALD AlN as an interfacial layer to avoid the formation of poor-quality oxide at the dielectric/(Al)GaN interface. We also develop an ALD AlHfON as a bulk layer, which have a high dielectric constant and low leakage current and high breakdown field characteristics. Devices with AlN/AlON/AlHfON layer show smaller I-V hysteresis of ~10 mV than that of devices with AlON/AlHfON layer. The extracted static Ron values of devices with AlN/AlON/AlHfON and AlON/AlHfON are 1.35 and 1.69 mโ„ฆยทcm2, respectively. Besides, the effective mobility, Dit and threshold voltage instability characteristics are all improved by employing the ALD AlN. In conclusion, for high performance and improvement of reliability of normally-off AlGaN/GaN MIS-FETs, this thesis presents an etching technique for low damage etching and high-quality gate dielectric layer and suggests that the ALE and ALD AlN/AlON/AlHfON gate dielectric are very promising for the future normally-off AlGaN/GaN MIS-FETsChapter 1. Introduction 1 1.1. Backgrounds 1 1.2. Normally-off Operation in AlGaN/GaN HFETs 3 1.3. Issues and Feasible Strategies in AlGaN/GaN MIS-HFETs 11 1.4. Research Aims 15 1.5. References 17 Chapter 2. Development and Evaluation of Low Damage Etching processes 22 2.1. Introduction 22 2.2. Various Evaluation Methods of Etching Damage 24 2.3. Low-Damage Dry Etching Methods 29 2.3.1. Inductively Coupled Plasma-Reactive Ion Etching Using BCl3/Cl2 Gas Mixture 29 2.3.2. Digital Etching Using Plasma Asher and HCl 34 2.3.3. Atomic Layer Etching Using Inductively Coupled Plasmaโ€“Reactive Ion Etching System (ICP-RIE) 50 2.4. Conclusion 75 2.5. References 76 Chapter 3. SiON/HfON Gate Dielectric Layer by ALD for AlGaN/GaN MIS-FETs 80 3.1. Introduction 80 3.2. ALD Processes for SiON and HfON 83 3.3. Electrical Characteristics of ALD SiON, HfON and SiON/HfON Dual Layer on n-GaN 87 3.4. Device Characteristics of Normally-off AlGaN/GaN MIS-FETs with SiON/HfON Dual Layer 95 3.5. Conclusion 113 3.6. References 114 Chapter 4. High Quality AlN/AlON/AlHfON Gate Dielectric Layer by ALD for AlGaN/GaN MIS-FETs 120 4.1. Introduction 120 4.2. Development of ALD AlN/AlON/AlHfON Gate Stack 122 4.2.1. Process Optimization for ALD AlN 122 4.2.2. ALD AlN as an Interfacial Layer 144 4.2.3. Thickness Optimization of AlN/AlON/ AlHfON Layer 149 4.2.4. ALD AlHfON Optimization 159 4.2.5. Material Characteristics of AlN/AlON/AlHfON Layer 167 4.3. Device Characteristics of Normally-off AlGaN/GaN MIS-FETs with AlN/AlON/AlHfON Layer 171 4.4. Conclusion 182 4.5. References 183 Chapter 5. Concluding Remarks 188 Appendix. 190 A. N2 Plasma Treatment Before Dielectric Deposition 190 B. Tri-gate Normally-on/off AlGaN/GaN MIS-FETs 200 C. AlGaN/GaN Diode with MIS-gated Hybrid Anode and Edge termination 214 Abstract in Korean 219 Research Achievements 221Docto

    Novel Metamaterials and Their Applications in Subwavelength Waveguides, Imaging and Modulation

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    The development of metamaterials has opened the door for engineering electromagnetic properties by subwavelength artificial atoms , and hence accessing new properties and functionalities which cannot be found among naturally occurring materials. In particular, metamaterials enable the flexibility of independently controlling the permittivity and permeability to be almost any arbitrary value, which promises to achieve deep subwavelength confinement and focusing of electromagnetic waves in different spectrum regimes. The next stage of this technological revolution will be focused on the development of active and controllable metamaterials, where the properties of the metamaterials are expected to be tuned by external stimuli. In this sense, some natural materials are also promising to provide the tunable capability, particularly in the near infrared and terahertz domains either by applying a voltage or shining light on the materials. The objective of this dissertation is to investigate novel metamaterials and explore three important applications of them: subwavelength waveguiding, imaging and modulation. The first part of this dissertation covers the theory, design and fabrication of several different types of metamaterials, which includes artificially designed metamaterials and some naturally existing materials. The second part demonstrates metal gratings functioning as designer surface plasmonic waveguides support deep subwavelength surface propagation modes at microwave frequency. The third part proposes multilayered metal-insulator stack as indefinite metamaterial that converts evanescent waves to propagating waves, hence deep subwavelength image can be observed. The fourth part explores the tunability of several natural materials - gallium (Ga), indium tin oxide (ITO) and graphene, and demonstrates electro-optical (EO) modulators based on these materials can be achieved on nano-scale. The final part summarizes the work presented in this dissertation and also discusses some future work for photodetection, photovoltaics, and modulation

    Micro- and Nanotechnology of Wide Bandgap Semiconductors

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    Owing to their unique characteristics, direct wide bandgap energy, large breakdown field, and excellent electron transport properties, including operation at high temperature environments and low sensitivity to ionizing radiation, gallium nitride (GaN) and related group III-nitride heterostructures proved to be enabling materials for advanced optoelectronic and electronic devices and systems. Today, they are widely used in high performing short wavelength light emitting diodes (LEDs) and laser diodes (LDs), high performing radar, wireless telecommunications, as well โ€˜greenโ€™ power electronics. Impressive progress in GaN technology over the last 25 years has been driven by a continuously growing need for more advanced systems, and still new challenges arise and need to be solved. Actually, lighting industry, RF defene industry, and 5G mmWave telecommunication systems are driving forces for further intense research in order to reach full potential of GaN-based semiconductors. In the literature, there is a number of review papers and publications reporting technology progress and indicating future trends. In this Special Issue of Electronics, eight papers are published, the majority of them focusing materials and process technology of GaN-based devices fabricated on native GaN substrates. The specific topics include: GaN single crystalline substrates for electronic devices by ammonothermal and HVPE methods, Selective โ€“ Area Metalorganic Vapour โ€“ Phase Epitaxy of GaN and AlGaN/GaN hetereostructures for HEMTs, Advances in Ion Implantation of GaN and Related Materials including high pressure processing (lattice reconstruction) of ion implanted GaN (Mg and Be) and III-Nitride Nanowires for electronic and optoelectronic devices

    Feature Papers in Electronic Materials Section

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    This book entitled "Feature Papers in Electronic Materials Section" is a collection of selected papers recently published on the journal Materials, focusing on the latest advances in electronic materials and devices in different fields (e.g., power- and high-frequency electronics, optoelectronic devices, detectors, etc.). In the first part of the book, many articles are dedicated to wide band gap semiconductors (e.g., SiC, GaN, Ga2O3, diamond), focusing on the current relevant materials and devices technology issues. The second part of the book is a miscellaneous of other electronics materials for various applications, including two-dimensional materials for optoelectronic and high-frequency devices. Finally, some recent advances in materials and flexible sensors for bioelectronics and medical applications are presented at the end of the book

    Wide Bandgap Based Devices: Design, Fabrication and Applications, Volume II

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    Wide bandgap (WBG) semiconductors are becoming a key enabling technology for several strategic fields, including power electronics, illumination, and sensors. This reprint collects the 23 papers covering the full spectrum of the above applications and providing contributions from the on-going research at different levels, from materials to devices and from circuits to systems

    Plasma-Enhanced Chemical Vapor Deposition: Where we are and the Outlook for the Future

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    Chemical vapor deposition (CVD) is a technique for the fabrication of thin films of polymeric materials, which has successfully overcome some of the issues faced by wet chemical fabrication and other deposition methods. There are many hybrid techniques, which arise from CVD and are constantly evolving in order to modify the properties of the fabricated thin films. Amongst them, plasma enhanced chemical vapor deposition (PECVD) is a technique that can extend the applicability of the method for various precursors, reactive organic and inorganic materials as well as inert materials. Organic/inorganic monomers, which are used as precursors in the PECVD technique, undergo disintegration and radical polymerization while exposed to a high-energy plasma stream, followed by thin film deposition. In this chapter, we have provided a summary of the history, various characteristics as well as the main applications of PECVD. By demonstrating the advantages and disadvantages of PECVD, we have provided a comparison of this technique with other techniques. PECVD, like any other techniques, still suffers from some restrictions, such as selection of appropriate monomers, or suitable inlet instrument. However, the remarkable properties of this technique and variety of possible applications make it an area of interest for researchers, and offers potential for many future developments

    Deposiรงรฃo de filmes do diamante para dispositivos electrรณnicos

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    This PhD thesis presents details about the usage of diamond in electronics. It presents a review of the properties of diamond and the mechanisms of its growth using hot filament chemical vapour deposition (HFCVD). Presented in the thesis are the experimental details and discussions that follow from it about the optimization of the deposition technique and the growth of diamond on various electronically relevant substrates. The discussions present an analysis of the parameters typically involved in the HFCVD, particularly the pre-treatment that the substrates receive- namely, the novel nucleation procedure (NNP), as well as growth temperatures and plasma chemistry and how they affect the characteristics of the thus-grown films. Extensive morphological and spectroscopic analysis has been made in order to characterise these films.Este trabalho discute a utilizaรงรฃo de diamante em aplicaรงรตes electrรณnicas. ร‰ apresentada uma revisรฃo detalhada das propriedades de diamante e dos respectivos mecanismos de crescimento utilizando deposiรงรฃo quรญmica a partir da fase vapor com filament quente (hot filament chemical vapour deposition - HFCVD). Os detalhes experimentais relativos ร  otimizaรงรฃo desta tรฉcnica tendo em vista o crescimento de diamante em vรกrios substratos com relevรขncia em eletrรณnica sรฃo apresentados e discutidos com detalhe. A discussรฃo inclui a anรกlise dos parรขmetros tipicamente envolvidos em HFCVD, em particular do prรฉ-tratamento que o substrato recebe e que รฉ conhecido na literatura como "novel nucleation procedure" (NNP), assim como das temperaturas de crescimento e da quรญmica do plasma, bem como a influรชncia de todos estes parรขmetros nas caracterรญsticas finais dos filmes. A caracterizaรงรฃo morfolรณgica dos filmes envolveu tรฉcnicas de microscopia e espetroscopia.Programa Doutoral em Engenharia Eletrotรฉcnic
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