Efficient Dislocation Reduction Methods for Integrating Gallium Nitride HEMTs on Si
Electronic Theses of Indian Institute of Science
View Archive InfoField | Value | |
Title |
Efficient Dislocation Reduction Methods for Integrating Gallium Nitride HEMTs on Si
|
|
Creator |
Mohan, Nagaboopathy
|
|
Subject |
Gallium Nitrides
Gallium Nitride Alloys Gallium Nitride Dislocation Reduction Gallium Nitride on Silicon High Electron Mobility Transistors Si Doping GaN Materials Science |
|
Description |
Gallium Nitride (GaN) and its alloys with InN and AlN, the III-nitrides, are of interest for a variety of high power-high frequency electronics and optoelectronics applications. However, unlike Si and GaAs technology that have been developed on native substrates, III-nitride devices have been developed on non-native substrates such as Si, sapphire and SiC. This is because bulk cheap native III-nitride substrates are unavailable. Among the known substrates, III-nitride technology development on Si is desirable because of its large substrate size and low cost. However, the large lattice and thermal expansion mismatch between the III-nitrides films and Si substrate leads to a high level of dislocations, 1010 cm-2, and tensile stress which results in cracking. For successful integration of crack free and low dislocation density GaN on Si various kinds of transition layer schemes are used that help to incorporate a compressive growth stress to neutralize the tensile thermal mismatch stresses and also to reduce dislocation densities to levels required by devices. These transition schemes, ranging from 400 nm to 7 m, involve the use of graded AlGaN layers, high/low temperature interlayers and superlattices. The aim of the research described in this thesis was a systematic comparison of the different transition layer schemes currently used with the objective of increasing the efficiency of integrating device quality, crack free, low dislocation density, |
|
Contributor |
Raghavan, Srinivasan
|
|
Date |
2017-11-23T07:53:36Z
2017-11-23T07:53:36Z 2017-11-23 2014 |
|
Type |
Thesis
|
|
Identifier |
http://hdl.handle.net/2005/2789
http://etd.ncsi.iisc.ernet.in/abstracts/3656/G26626-Abs.pdf |
|
Language |
en_US
|
|
Relation |
G26626
|
|