Silicon-based electronics devices and integrated circuits have been the backbone of most modern technology, the demands for smaller and faster electronics have pushed the material towards its physical limitations. Compound semiconductor materials are growing in importance because of their ability to offer superior performance across a wide range of applications in optoelectronics and power electronics. Unfortunately, the adoption of these new materials has been hindered by the lack of cost-effective epitaxial substrates and the difficulties in integrating with existing processes. Additionally, the rigid wafers pose major challenges to future flexible electronics and the heterogeneous integration of dissimilar materials. To overcome these limitations, a new layer transfer technology based on remote epitaxy is developed. Remote epitaxy takes advantage of the atomic thickness of the two-dimensional (2D) material so that the wafer covered by 2D material can still be the substrate for epitaxial growth. At the same time, the weak van der Waals interaction between the 2D material and the epitaxial layer allows the epitaxial layer to be mechanically exfoliated precisely at the 2D material interface. In this work, the mechanism of remote epitaxy is systematically investigated. This work demonstrates that the strength of remote interaction between the substrate and epitaxial layer through 2D material is determined by the ionicity of the bulk materials and the thickness of the 2D interlayer. The 2D interlayer is transparent to such remote interaction unless it possesses periodic polar bonds. The remote epitaxy of gallium nitride (GaN) is studied in depth. Freestanding GaN thin film with a threading dislocation density of 2.1×107 cm−2 and electron mobility of 254 cm2/(V·s) is demonstrated. The thin film is then transferred onto a host substrate and the original substrate can be reused without refurbishment. The process demonstrated in this work can significantly reduce the production cost of compound semiconductor devices by reusing the expensive wafers. The free-standing crystalline thin films obtained by remote epitaxy can also be monolithically integrated to accommodate existing processes or create novel heterogeneous structures.

Gallium nitride is an important material for the production of next-generation visible and near-UV optical devices, as well as for high temperature electronic amplifiers and circuits; however there has been no bulk method for the production of GaN substrates for device layer growth. Instead, thick GaN layers are heteroepitaxially deposited onto non-native substrates (usually sapphire) by one of two vapor phase epitaxy (VPE) techniques: MOVPE (metalorganic VPE) or HVPE (hydride VPE). Each method has its strengths and weaknesses: MOVPE has precise growth rate and layer thickness control but it is slow and expensive; HVPE is a low-cost method for high rate deposition of thick GaN, but it lacks the precise control and heterojunction layer growth required for device structures. Because of the large (14%) lattice mismatch, GaN grown on sapphire requires the prior deposition of a low temperature MOVPE nucleation layer using a second growth process in a separate deposition system. Here we present a novel hybrid VPE system incorporating elements of both techniques, allowing MOVPE and HVPE in a single growth run. In this way, a thick GaN layer can be produced directly on sapphire. GaN growth commences as small (50-100 nm diameter) coherent strained 3-dimensional islands which coalesce into a continuous film, after which 2-dimensional layer growth commences. The coalescence of islands imparts significant stress into the growing film, which increases with the film thickness until catastrophic breakage occurs, in-situ. Additionally, the mismatch in thermal expansion rates induces compressive stress upon cooling from the growth temperature of 1025°C. We demonstrate a growth technique that mitigates these stresses, by using a 2-step growth sequence: an initial high growth rate step resulting in a pitted but relaxed film, followed by a low growth rate smoothing layer. As a result, thick (> 50 [Mu]m) and freestanding films have been grown successfully. X-ray rocking curve linewidth of 105 arcseconds and 10K PL indicating no "yellow" emission indicate that the material quality is higher than that produced by conventional MOVPE. By further modifying the hybrid system to include a metallic Mn source, it is possible to grow a doped semi-insulating GaN template for use in high frequency electronics devices.

Amorphous boron nitride (aBN) has found broad applications in industrial applications. Thick aBN has been thoroughly investigated1,2, including the recent revisiting of this material at nanometer thickness. However, most investigations of aBN so far have been based on three-dimensional structures. In this thesis, Molecular-Beam Epitaxy (MBE) grown monolayer aBN in two-dimensional structure is demonstrated. In-situ gallium nitride (GaN) remote epitaxy is finished on the transparent monolayer aBN. By doing the in-situ remote epitaxy, contaminations are avoided, and epitaxial membrane quality is improved. Multi-stacking technique is developed to further enhance the manufacturing efficiency of the free-standing GaN film. Surface acoustic wave (SAW) strain sensor fabricated by free-standing ultrathin single crystalline GaN film shows good performances. Process to solve GaN device heat dissipation is presented. Relaxed InGaN film grown on aBN monolayer provides a new research direction for GaN based red LED.

Addresses a Growing Need for High-Power and High-Frequency Transistors Gallium Nitride (GaN): Physics, Devices, and Technology offers a balanced perspective on the state of the art in gallium nitride technology. A semiconductor commonly used in bright light-emitting diodes, GaN can serve as a great alternative to existing devices used in microelectronics. It has a wide band gap and high electron mobility that gives it special properties for applications in optoelectronic, high-power, and high-frequency devices, and because of its high off-state breakdown strength combined with excellent on-state channel conductivity, GaN is an ideal candidate for switching power transistors. Explores Recent Progress in High-Frequency GaN Technology Written by a panel of academic and industry experts from around the globe, this book reviews the advantages of GaN-based material systems suitable for high-frequency, high-power applications. It provides an overview of the semiconductor environment, outlines the fundamental device physics of GaN, and describes GaN materials and device structures that are needed for the next stage of microelectronics and optoelectronics. The book details the development of radio frequency (RF) semiconductor devices and circuits, considers the current challenges that the industry now faces, and examines future trends. In addition, the authors: Propose a design in which multiple LED stacks can be connected in a series using interband tunnel junction (TJ) interconnects Examine GaN technology while in its early stages of high-volume deployment in commercial and military products Consider the potential use of both sunlight and hydrogen as promising and prominent energy sources for this technology Introduce two unique methods, PEC oxidation and vapor cooling condensation methods, for the deposition of high-quality oxide layers A single-source reference for students and professionals, Gallium Nitride (GaN): Physics, Devices, and Technology provides an overall assessment of the semiconductor environment, discusses the potential use of GaN-based technology for RF semiconductor devices, and highlights the current and emerging applications of GaN.

III-Nitride Electronic Devices, Volume 102, emphasizes two major technical areas advanced by this technology: radio frequency (RF) and power electronics applications. The range of topics covered by this book provides a basic understanding of materials, devices, circuits and applications while showing the future directions of this technology. Specific chapters cover Electronic properties of III-nitride materials and basics of III-nitride HEMT, Epitaxial growth of III-nitride electronic devices, III-nitride microwave power transistors, III-nitride millimeter wave transistors, III-nitride lateral transistor power switch, III-nitride vertical devices, Physics-Based Modeling, Thermal management in III-nitride HEMT, RF/Microwave applications of III-nitride transistor/wireless power transfer, and more. Presents a complete review of III-Nitride electronic devices, from fundamental physics, to applications in two key technical areas - RF and power electronics Outlines fundamentals, reviews state-of-the-art circuits and applications, and introduces current and emerging technologies Written by a panel of academic and industry experts in each field