Innovative approaches for alganganbased technology white. Conventional gan based transistors are of the high e. The 2d electron gas plays an important role in determining the. Algangan based enhancement mode moshemts enlighten. Large signal modelling of algan gan hemt for linearity prediction thesis presented in partial fulfillment of the requirements for the degree master of science in the graduate school of the ohio state university by preethi someswaran graduate program in electrical and computer engineering the ohio state university 2015. Sep 24, 2015 this paper presents two structures of wide band gap high electron mobility transistor hemt. This work focused on the tcad simulation and modeling of algangan hfets. A spectrum of phenomena related to the reliability of algan gan hemts are investigated in this thesis using numerical simulations. International journal of science and research ijsr is published as a monthly journal with 12 issues per year.
Gan materials have high thermal and chemical stability. The surface states assumed in the model are a key variable since the device response is determined by their magnitude. In table 1 the attributes of gan on gan is compared with gan on nonnative substrates. Algangan hfets have demonstrated excellent rf performance, which benefits from the high sheet charge density in these heterostructures, the high carrier mobility and saturation velocity in the channel, and the high breakdown voltage inherent in the gan material. Algan gan hemt devices tested the algan gan hemt based hybrid test amplifiers were designed and developed. Fabrication and characterization of zno and gan devices for. This paper presents two structures of wide band gap high electron mobility transistor hemt. With these progresses, many working groups study algan gan structure intensively concerning versatile applications such as. Algangan mishemts with aln gate dielectric grown by thermal.
Design and modeling of highpower semiconductor devices with emphasis on algan gan hemts thesis for the degree of philosophiae doctor trondheim, october 20 norwegian university of science and technology faculty of information technology, mathematics and electrical engineering department of electronics and telecommunications nitin goyal. Design and modeling of highpower semiconductor devices with emphasis on algangan hemts thesis for the degree of philosophiae doctor trondheim, october 20 norwegian university of science and technology faculty of information technology, mathematics and electrical engineering department of electronics and telecommunications nitin goyal. In this new fabrication technology, the gate stack is deposited before the ohmic contacts, and it is optimized to stand the 870degc ohmic contact annealing. Iiinitrides electronic characteristics ensure they are presently materials loved by highpower highfrequency applications. Innovative approaches for algangan based technology by turar baltynov a thesis submitted in partial fulfilment of the requirements for the degree of doctor of philosophy the university of sheffield faculty of engineering department of electronic and electrical engineering february 2016. Another interesting mobility increasing modification of the alganhemt is to introduce an algan alloy into the gan buffer layer. The devices are simulated in silvaco atlas tcad with a velocity saturation. Algangan epitaxy and technology international journal. Gan devices had previously been tested for tid damage, and the dc characteristics had been shown to be stable to very high doses.
For two dimensional electron gas 2deg density calculation of algangan hemt, we used algan barrier with different al composition on gan substrate with thickness varying from 20nm to 30nm. Design and modeling of high power semiconductor devices with. As a result, on resistance can be lower commonly vertical power device. Algan gan hemt phd thesis proposal i help to study. Physical degradation and preparation for insitu microscopy of alganganbased hemts a thesis submitted to the faculty of drexel university by. Development and modeling of a biosensor platform using.
Advanced polarizationbased design of algan gan hemts by likun shen during the past few years, enormous progress has been made in the development of gan based devices. State of the art 2d and 3d process and device simulation of ganbased devices. In fact, any action on the gate voltage vgs has the effect to modify the electronic population of the channel which varies. The work in this thesis focuses on algangan high electron mobility transistors hemts in. In this paper, for the first time, we report the uniformity of the electrical performances of algan gan hemts on a 200mm diameter si111 substrate. Round hemttechnology, which greatly simplifies the microelectronic fabrication process compared to traditional open fingers hemt, was employed. This masters thesis is a study of how the aln exclusionlayer and double heterojunction affect the electrical properties of an algangan heterostructure. Radiation response and reliability of algangan hemts. A longterm 3000hour test under onstate conditions v ds 25v, 6wmm constant dissipated power and offstate conditions v ds 46v, v gs 6v on gan algan gan hemts is presented. A spectrum of phenomena related to the reliability of algangan hemts are investigated in this thesis using numerical simulations.
Since their advent, polar algangan heterojunction field effect transistors hfets have drawn a great deal of attention especially in high frequencyhigh power applications. Fabrication and physicsbased modeling of polar algangan and. Algangan hemt topology investigation using measured. Trap states plays an important role in algan gan hemt device performance. Dec 29, 2011 highelectronmobility transistors hemts with a highly resistive twolayer buffer layer algan gan were grown on 6hsic substrates by metalorganic chemical vapor deposition. In this paper, the electrical characteristics analysis is determined for the nanogan hemt and microgan hemt and also power spectrum density is determined for gan nanohemt by reducing the gate length lg in nm range. Planview cathodeluminescence cl imaging reveals that the threading dislocation density in the films grown over bulk gan substrates is limited by the defect density in the substrate and many orders of magnitude smaller compared with the material grown on silicon, sapphire, or sic substrates. Processing, portrayal and modeling of algangan hemts. Supervision by derrick langley entitled algangan hemt topology investigation using measured data and device modeling be accepted in partial fulfillment of the requirements for the degree of master of science in engineering. Large signal modelling of algangan hemt for linearity.
This information can be used to improve the stability of threshold voltage of algangan hemt device by decreasing or eliminating the interface states. The results of xray diffraction and atomic force microscopy indicate that the crystal quality of the hemt. Notably, it is a referred, highly indexed, online international journal with high impact factor. Development of algangan hemts on different substrates ming pan, xiang gao, daniel gorka, mark oliver, and shiping guo iqe rf, llc. A physicsbased analytical model of an algangan high. New concepts for normallyoff power gallium nitride gan. One structure is madeup of a stack of algan layer over gan layer. Gallium nitride gan has been proven to be a very suitable material for advanced power electronics on account of its outstanding material properties. This letter describes a gatefirst algangan highelectron mobility transistor hemt with a whighk dielectric gate stack. A physicsbased analytical model of an aigangan high electron mobility transistor i, jonathan c. Innovative approaches for alganganbased technology.
Power electronics is the requisite interface between an electrical source and a load. Nano technology is the branch of technology that deals with dimensions and tolerances in terms of nanometers. The sentaurus software simulates the dc and ac characteristics of the two algangan hemt structures. Comparative study between algangan and alinngan high.
However, thermal and power density limitations have. The results of xray diffraction and atomic force microscopy indicate that the. Reliability studies of vertical gan devices based on bulk gan. A thesis submitted to the nanyang technological university. The characteristics were compared with those of conventional hemts utilizing gan as the highresistivity buffer. Theoretical onresistance ron limit exists for the lateral power device, which shows table1.
The work in this thesis focuses on algangan high electron mobility transistors hemts in particular, with the aim of gaining the maximum. One of the issues of algan gan hemt is specific contact resistivity con. Gallium nitride high electron mobility transistor gan. Iv characteristics model for algangan hemts using tcadsilvaco. Effect of gan cap layer on the electrical properties of. This structure is characterized by twodimensional 2d electron gas layer formed at the interface of the algan and gan layers. Highelectronmobility transistors hemts with a highly resistive twolayer buffer layer algangan were grown on 6hsic substrates by metalorganic chemical vapor deposition. Design and modeling of high power semiconductor devices. In this paper, a novel gate dielectric and passivation technique for ganonsi algangan metalinsulatorsemiconductor highelectronmobility. Any reproduction will not be for commercial use or profit. This thesis describes a new gallium nitride gan based transistor technology for electronic switching applications. Reduction of current collapse in algangan hemts using thick. University of california santa barbara understanding material and process limits for high breakdown voltage algan gan hemts a dissertation submitted in partial satisfaction of the requirements for the degree of doctor of philosophy in electrical and computer engineering by yuvaraj dora committee in charge. Algangan epitaxy and technology volume 2 issue 1 patrick waltereit, wolfgang bronner, rudiger quay, michael dammann, rudolf kiefer, wilfried pletschen, stefan muller, rolf aidam, hanspeter menner, lutz kirste, klaus kohler, michael mikulla, oliver ambacher.
Another feature of gan is lateral power device structure which can drift current lateral direction. Iv characteristics model for algangan hemts jntm2014 a. A thresholdvoltagebased 2d theoretical model for the currentvoltage characteristics of the algangan high electron mobility transistors hemts is developed. Sep 03, 2014 matteo meneghini received the laurea degree summa cum laude in electronics engineering, with a thesis on the electrical and optical characterization of gallium nitride lightemitting diodes leds, and the ph. Reduction of current collapse in algangan hemts using. Fabrication and characterization of zno and gan devices. Improvement of breakdown characteristics of a gan hemt with. Fabrication and physicsbased modeling of polar algangan. Design and fabrication of algangan hemts with high breakdown. But the tid effect on the rf characteristics had not been reported. Modeling of noise power spectral density analysis for gan. In this work, we grew the same algangan hemt structures on 200mm si111 substrates using three different buffer layers configurations such that all wafers are crackfree and have a small bow.
The focus is on trap related phenomena that lead to decrease in the power output and failure of devices, i. Today, researchers are exploring gan based high electron mobility transistors hemts for conventional as well as highend solutions in the range of 600 1200 v. Nov 21, 2016 algan gan high electron mobility transistors hemts are being investigated for high power high frequency applications as iiinitride i. Reliability studies of vertical gan devices based on bulk. Today, researchers are exploring ganbased high electron mobility transistors hemts for conventional as well as highend solutions in the range of 600 1200 v. I feel fortunate to be at uc santa barbara to pursue my ph. Reliability of algangan hemts for rf and microwave applications. Iv characteristics model for algangan hemts using tcad.
Recently algangan high electron mobility transistors hemts have made rapid progress in its characteristics as a high power microwave devices. Another interesting mobility increasing modification of the algan hemt is to introduce an algan alloy into the gan buffer layer. Improvement of breakdown characteristics of a gan hemt. Ups,dps evhev robot weld medical device air conditioner electric cooker. College dissertation from chalmers college of technology. As part of this thesis, reverse gateleakage of algan gan hfets is studied over a wide range of latticetemperatures. Characterization of algangan and alganalngan hemts in. In this paper, a novel gate dielectric and passivation technique for gan onsi algan gan metalinsulatorsemiconductor highelectronmobility transistors mishemts is.
Processing, portrayal and modeling of algan gan hemts. Journal of applied mathematics and physics, 4, 19061915. Algangan hemt structures on ammono bulk gan substrate. In this paper, we report the growth results of the first algangan hemt structures on the ammonothermal gan ammonogan substrate which have dislocation density as low as 10 4 cm.
Design and fabrication of algangan hemts with high. Iv characteristics model for algangan hemts using tcadsilvaco abdelmalek douaraa, bouaza djelloulib, abdelaziz rabehic, abderrezzak zianec and nabil belkadic a applied materials laboratory, research center, university djillali liabes of sidi bel abbes, 22000 sidi bel abbes, algeria b laboratory of modelling and calculation methods lmcm, 20002 university of saida. On the second part of the dissertation, aluminum gallium nitride gallium nitride high electron mobility transistors algangan hemts were fabricated. However, the superb prospects of these transistors are affected by a few drawbacks such as agingcrack formation under strain, presence of high gateleakage, and challenging realization of enhancementmode. Current collapse and device degradation in algangan. A 3000 hours dc life test on algangan hemt for rf and.
Overview of algangan hemt technology for l to kuband applications article pdf available in international journal of microwave and wireless technologies 201. Round hemttechnology, which greatly simplifies the microelectronic fabrication process compared to. The new processes will be used for highly efficient highpower transistors based on algan gan heterojunction field effect transistors hfets offering novel solutions for highend applications. Development of slanted gates for algangan hemts research. This masters thesis is a study of how the aln exclusionlayer and double heterojunction affect the electrical properties of an algan gan heterostructure. The great interest raised by algangan highelectron mobility transistors hemts in the international semiconductor scientific community in general, for highfrequency, highpower, and hightemperature applications, has resulted in that an important number of researchers and centers in the world are nowadays mainly devoted to this new technology. However, thermal and power density limitations have impeded the achievement of. The electrical properties of algangan heterojunction high electron mobility transistor hemt are simulated by using sentaurus software.
Some examples of power electronic systems are a laptop charger converting 90260 v ac power to 19 v3. Daniel balaz from his phd thesis from university of glasgow in 2011 entitled current collapse and device degradation in algangan heterostructure field effect transistors. Algangan epitaxy and technology international journal of. Gallium nitride high electron mobility transistor ganhemt technology for high gain and highly efficient power amplifiers. Pdf reliability of algangan hemts for rf and microwave. Gatefirst algangan hemt technology for highfrequency. Si3n4 passivated algangan highelectronmobility transistors, applied physics letter, 89 2006 p. This letter describes a gatefirst algan gan highelectron mobility transistor hemt with a whighk dielectric gate stack. Algan gan hfets have demonstrated excellent rf performance, which benefits from the high sheet charge density in these heterostructures, the high carrier mobility and saturation velocity in the channel, and the high breakdown voltage inherent in the gan material. The current collapse phenomenon has been largely suppressed using sin passivation, but. Reliability of algangan hemts for rf and microwave. Algangan hemt devices tested the algangan hemtbased hybrid test amplifiers were designed and developed. Trapping effects in the transient response of algangan.
Recently algan gan high electron mobility transistors hemts have made rapid progress in its characteristics as a high power microwave devices. Sippel, hereby grant permission to wallace memorial library of the rochester institute of technology to reproduce my thesis in whole or in part. This paper compares two structures, the hemt with gan cap layer and the hemt without gan cap layer. The source and load can differ in frequency, amplitude, number of phases, and where voltages and currents are converted from one form to another. Trapping effects in the transient response of algangan hemt. Development of algangan hemts on different substrates. It shows that interface traps at algangan interface play an important role in threshold voltage shift. Donor like surface states is believed to be responsible for formation of two dimensional electron gas at algan gan interface even without any intentional doping. As shown below, reasonable values, coherent with the measured curves, for the density of donor traps were t1 1. In this paper, for the first time, we report the uniformity of the electrical performances of algangan hemts on a 200mm diameter si111 substrate. Algangan mishemts with aln gate dielectric grown by. Reliability of algangan hemts for rf and microwave applications thesis pdf available.
This version of the hemt is known as the double heterojunction. Showing result 1 to five of 17 swedish dissertations containing the text gan hemts 1. The algangan heterostructure was grown on a 4in sapphire substrate using metalorganic chemical vapor deposition, which consists of a lowtemperature initial nucleation layer, 2. Pdf overview of algangan hemt technology for l to ku. Ohmic contacts and thin film resistors for gan mmic technologies.
Gallium nitride gan based high electron mobility transistor hemt technologies have attracted much attention within the last decade that has introduced to have an immediate rise in material quality and device performance. One of the most important device characteristics of algan gan hfets which is often poorly understood is the gateleakage current. Reduction of current collapse in algangan hemts using thick gan cap layer hiroshi chonan1, yuichi sakamura 2, guanxi piao2, toshihide ide 2, mitsuaki shimizu2, yoshiki yano 3, hisayuki nakanishi1 1 department of electrical engineering, faculty of science and technology, tokyo university of science. Large signal modelling of algangan hemt for linearity prediction thesis presented in partial fulfillment of the requirements for the degree master of science in the graduate school of the ohio state university by preethi someswaran graduate program in electrical and computer engineering the ohio state university 2015. The work in this thesis focuses on algan gan high electron mobility transistors hemts in particular, with the aim of gaining the maximum potential out of them. Due to high breakdown field, high sheet charge density and high electron saturation velocity, gan based hemts have great potential for high frequency high power applications. Advanced polarizationbased design of algangan hemts. Abstractdifferent characteristics of algangan and alinngan high electron mobility transistors hemts are compared in this paper. Gate fabrication is a crucial part in transistor manufacturing due to its strong influence on device performance and reliability. State of the art 2d and 3d process and device simulation. Recently, aln plasmaenhanced atomic layer deposition ald passivation technique had been proposed and investigated for suppressing the dynamic onresistance degradation behavior of highelectronmobility transistors hemts. This work focused on the tcad simulation and modeling of algan gan hfets.
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