Download or read book Design and Fabrication of GaN based Heterojunction Bipolar Transistors written by Kyu-Pil Lee and published by . This book was released on 2003 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Fabrication of Gallium Nitride silicon Carbide Heterojunction Bipolar Transistors written by Hong Wu and published by . This book was released on 2003 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growth and Fabrication of GaN Based Heterojunction Bipolar Transistors written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: GaN HBTs are promising for microwave power applications but face numerous technology barriers. In this project, we are addressing the enhancement of the hole concentration in p-type GaN by piezoelectric effects and/or the use of superlattices. We are currently assessing the activity of Mg-doped GaN on sapphire and lithium gallate as grown by MBE. In addition, we are modeling these effects to optimize the hole concentration in realistic HBT structures.

Download or read book Design and Fabrication of InGaN GaN Heterojunction Bipolar Transistors for Microwave Power Amplifiers written by David Martin Keogh and published by . This book was released on 2006 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: The GaN material system is widely recognized for its opto-electronic properties, with the recent commercialization of blue, green, and violet light emitting devices, but also has enormous potential for high power applications across a range of frequencies. The combination of high breakdown field, high electron saturation velocity, and high thermal conductivity, make it especially useful for delivering high power at high frequencies for wireless base stations, emerging WiMAX technology, and satellite communications. Though HEMTs have shown impressive performance, HBTs have many advantages as compared to HEMTs, and therefore represent an important technology. Bipolar technology, however, has not achieved the same level of success as HEMTs, as a result of some important technological obstacles. For example, the main issue with GaN-based HBTs is the issue of acceptor impurity activation, which is typically less than 1% for GaN, limiting free hole concentrations to less than 1x1018 cm-3. Through the use of InGaN alloys in the base of an HBT, however, it is possible to achieve doping levels greater than 1x1019 cm-3, with higher mobilities and less lattice damage, enabling a high performance RF device. This dissertation embodies the design, fabrication, and characterization of InGaN/GaN HBTs under DC and RF conditions. Design of the epitaxial layer structure accounts for the piezo-electric and polarization effects present in the nitrides, which is critical for proper device operation. Furthermore, the DC and RF performance is simulated using physically based TCAD device design software to estimate the performance of an InGaN/GaN HBT. In addition, the performance of a fully-matched Class-B power amplifier is simulated at 1 GHz. Processing of InGaN/GaN HBTs was a significant portion of this thesis, and as such, a robust scheme for their fabrication was developed. Dry-etching was accomplished using Inductively Coupled Plasma (ICP), and the effects of etch conditions on the characteristics of the device explored. Also, boiling KOH solutions were found to be useful for improving the surface quality after dry-etching, and as part of a digital etching process. The final process enabled the successful fabrication of InGaN/GaN HBTs with excellent DC performance, and a maximum cut-off frequency of 0.8 GHz.

Download or read book Growth and Fabrication of GaN Based Heterojunction Biopolar Transistors written by and published by . This book was released on 2000 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this progress report, we summarize the results to date of experiments to prove the existence of a two dimensional hole gas. If possible, this hole gas will result in enhanced performance Heterojunctions bipolar transistors for military and commercial applications. Also summarized is the background work required to achieve the two dimensional hole gas including several never before reported results on the behavior of p-type dopants in III-Nitrides.

Download or read book Design Fabrication and Evaluation of High speed III V based Heterojunction Bipolar Transistors written by Bo Willén and published by . This book was released on 1998 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation Design and Fabrication of InP based Pnp Heterojunction Bipolar Transistors written by Suman Datta and published by . This book was released on 1999 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Realization of Bipolar Transistors written by Peter Ashburn and published by . This book was released on 1988-08-18 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Addresses new developments in the design and fabrication of bipolar transistors for high-speed digital circuits. Covers advances in silicon technology (such as polysilicon emitters and self-aligned fabrication techniques), gallium arsenide technology (such as extremely high-performance MSI circuits resulting from the development of GaAs/GaAlAs heterojunctions), and new applications of bipolar transistors (such as optoelectronic circuits). Also deals with optimization of bipolar devices and processes for high-speed, digital circuits by means of a quasi-analytical expression for the gate delay of an ECL logic gate. Includes case studies.

Download or read book Gan based Materials And Devices Growth Fabrication Characterization And Performance written by Robert F Davis and published by World Scientific. This book was released on 2004-05-07 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique materials properties of GaN-based semiconductors have stimulated a great deal of interest in research and development regarding nitride materials growth and optoelectronic and nitride-based electronic devices. High electron mobility and saturation velocity, high sheet carrier concentration at heterojunction interfaces, high breakdown field, and low thermal impedance of GaN-based films grown over SiC or bulk AlN substrates make nitride-based electronic devices very promising. The chemical inertness of nitrides is another key property.This volume, written by experts on different aspects of nitride technology, addresses the entire spectrum of issues related to nitride materials and devices, and it will be useful for technologists, scientists, engineers, and graduate students who are working on wide bandgap materials and devices. The book can also be used as a supplementary text for graduate courses on wide bandgap semiconductor technology.

Download or read book Design and Fabrication of Heterojunction Bipolar Transistors HBT written by Yang Pan and published by . This book was released on 2000 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Demonstration and Modeling of a Nitride based Heterojunction Bipolar Transistor Using Nanomembrane Transfer written by Clincy Cheung and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterojunction bipolar transistors (HBT) are sought as a building block for implementation of modern broadband electronics, defense applications, and other mm-wave electronic systems demanding in high-speed and high-power performance. The push for greater frequency performance, higher power densities and reliability have pushed research towards wide-bandgap materials such as Gallium Nitride (GaN) given its superior intrinsic material properties, providing for higher breakdown voltage, and enabling higher power performance. However, GaN faces a fundamental limitation with p-type doping, limiting its adoption in RF power electronics. Attempts at a wide bandgap HBT to-date has exclusively relied on epitaxial growth using metal-organic chemical vapor deposition or molecular beam epitaxy (MBE) to fabricate a GaN-based transistor; however, none have yielded a device with both sufficient current gain and transition frequency - both key measures of performance in a bipolar transistor. Alternative materials for the different HBT layers have been considered but are limited by significant lattice mismatch. To bypass p-type GaN limitations and improve the base-collector junction with minimal interface trap density, a nanomembrane interlayer device transfer is proposed as an alternative for fabrication of an HBT. There are two aims in this dissertation: to demonstrate an experimental HBT with a sufficient current gain above 20 and demonstrate using computer-aided modeling that sufficient frequency performance can be achieved - both to demonstrate that a wide-bandgap HBT is both possible and worth further exploration for RF electronics. In Chapter 1, the landscape of research into wide-bandgap bipolar transistors is presented. In Chapter 2, multiple methods of integration for different diode pairs within the HBT are evaluated for probability of success in the overall device, where a GaAs-GaN base-collector diode is demonstrated to have the best performance using nanomembrane layer transfer. Additionally, an MBE-grown AlGaAs-GaAs film stack was transferred and demonstrated an emitter-base structure can be transferred with no degradation in performance. In Chapter 3, fabrication of the HBT is demonstrated using the best methods selected from Chapter 2, where a AlGaAs-GaAs-GaN HBT was demonstrated to have a current gain greater than 70. In Chapter 4, technology computer-aided design simulations were developed to validate the DC results shown in Chapter 2 and 3, and simulated transition frequencies of at least 60 GHz for the experimental structure fabricated in Chapter 3. Finally, in Chapter 5, next steps are outlined for exploration beyond this initial proof-of-concept device. Taken altogether, this dissertation serves to demonstrate a device structure with the potential to vastly exceed existing solutions that can be applied to a vast array of wide-bandgap materials without being limited by its p-type analogues, enabling performance for a wide array of applications in the next generations of electronics.

Download or read book Design Fabrication and Analysis of a Gallium Arsenide Heterojunction Bipolar Transistor written by Edward David Goff and published by . This book was released on 1991 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Fabrication of Lateral Silicon Germanium Heterojunction Bipolar Transistors written by Putapon Pengpad and published by . This book was released on 2008 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of III nitride Bipolar Devices written by Yun Zhang and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the development of III-nitride (III-N) bipolar devices for optoelectronic and electronic applications. Research mainly involves device design, fabrication process development, and device characterization for Geiger-mode gallium nitride (GaN) deep-UV (DUV) p-i-n avalanche photodiodes (APDs), indium gallium nitride (InGaN)/GaN-based violet/blue laser diodes (LDs), and GaN/InGaN-based npn radio-frequency (RF) double-heterojunction bipolar transistors (DHBTs). All the epitaxial materials of these devices were grown in the Advanced Materials and Devices Group (AMDG) led by Prof. Russell D. Dupuis at the Georgia Institute of Technology using the metalorganic chemical vapor deposition (MOCVD) technique. Geiger-mode GaN p-i-n APDs have important applications in DUV and UV single-photon detections. In the fabrication of GaN p-i-n APDs, the major technical challenge is the sidewall leakage current. To address this issue, two surface leakage reduction schemes have been developed: a wet-etching surface treatment technique to recover the dry-etching-induced surface damage, and a ledged structure to form a surface depletion layer to partially passivate the sidewall. The first Geiger-mode DUV GaN p-i-n APD on a free-standing (FS) c-plane GaN substrate has been demonstrated. InGaN/GaN-based violet/blue/green LDs are the coherent light sources for high-density optical storage systems and the next-generation full-color LD display systems. The design of InGaN/GaN LDs has several challenges, such as the quantum-confined stark effect (QCSE), the efficiency droop issue, and the optical confinement design optimization. In this dissertation, a step-graded electron-blocking layer (EBL) is studied to address the efficiency droop issue. Enhanced internal quantum efficiency (©3¡2©60́9©3℗Øâ0́(℗Ơ©2°©3¡2â2́Ơš©30́(©2℗đi) has been observed on 420-nm InGaN/GaN-based LDs. Moreover, an InGaN waveguide design is implemented, and the continuous-wave (CW)-mode operation on 460-nm InGaN/GaN-based LDs is achieved at room temperature (RT). III-N HBTs are promising devices for the next-generation RF and power electronics because of their advantages of high breakdown voltages, high power handling capability, and high-temperature and harsh-environment operation stability. One of the major technical challenges to fabricate high-performance RF III-N HBTs is to suppress the base surface recombination current on the extrinsic base region. The wet-etching surface treatment has also been employed to lower the surface recombination current. As a result, a record small-signal current gain (hfe)> 100 is achieved on GaN/InGaN-based npn DHBTs on sapphire substrates. A cut-off frequency (fT)> 5.3 GHz and a maximum oscillation frequency (fmax)> 1.3 GHz are also demonstrated for the first time. Furthermore, A FS c-plane GaN substrate with low epitaxial defect density and good thermal dissipation ability is used for reduced base bulk recombination current. The hfe> 115, collector current density (JC)> 141 kA/cm©3¡2©60́9©3℗Øâ0́(℗Ơ©5¡©3¡2â2́Ơš©30́(©2℗ø, and power density> 3.05 MW/cm©3¡2©60́9©3℗Øâ0́(℗Ơ©5¡©3¡2â2́Ơš©30́(©2℗ø are achieved at RT, which are all the highest values reported ever on III-N HBTs.

Download or read book Design Simulation and Fabrication of a Self aligned SiGe Based Heterojunction Bipolar Transistor for Low power Operation written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Fabrication and Characterization of InP based Heterojunction Bipolar Transistors written by James C. Vlcek and published by . This book was released on 1985 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book GaN based Materials and Devices written by Michael Shur and published by World Scientific. This book was released on 2004 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique materials properties of GaN-based semiconductors havestimulated a great deal of interest in research and developmentregarding nitride materials growth and optoelectronic andnitride-based electronic devices. High electron mobility andsaturation velocity, high sheet carrier concentration atheterojunction interfaces, high breakdown field, and low thermalimpedance of GaN-based films grown over SiC or bulk AlN substratesmake nitride-based electronic devices very promising.