Size dictated thermal conductivity of GaN

被引：92

作者：

Beechem, Thomas E. ^{[1
]}

McDonald, Anthony E. ^{[1
]}

Fuller, Elliot J. ^{[2
]}

Talin, A. Alec ^{[2
]}

Rost, Christina M. ^{[3
]}

Maria, Jon-Paul ^{[3
]}

Gaskins, John T. ^{[4
]}

Hopkins, Patrick E. ^{[4
]}

Allerman, Andrew A. ^{[1
]}

机构：

[1] Sandia Natl Labs, Albuquerque, NM 87123 USA

[2] Sandia Natl Labs, Livermore, CA 94551 USA

[3] North Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA

[4] Univ Virginia, Dept Mech & Aerosp Engn, Charlottesville, VA 22904 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2016年 / 120卷 / 09期

基金：

美国国家科学基金会;

关键词：

TIME-DOMAIN THERMOREFLECTANCE; OVERGROWN GAN/SAPPHIRE 0001; TEMPERATURE-DEPENDENCE; RAMAN-SPECTROSCOPY; GALLIUM NITRIDE; LATTICE WAVES; SCATTERING; FILMS; DISLOCATIONS; IMPURITIES;

D O I：

10.1063/1.4962010

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The thermal conductivity of n- and p-type doped gallium nitride (GaN) epilayers having thicknesses of 3-4 mu m was investigated using time domain thermoreflectance. Despite possessing carrier concentrations ranging across 3 decades (10(15) - 10(18) cm(-3)), n-type layers exhibit a nearly constant thermal conductivity of 180 W/mK. The thermal conductivity of p-type epilayers, in contrast, reduces from 160 to 110 W/mK with increased doping. These trends-and their overall reduction relative to bulk-are explained leveraging established scattering models where it is shown that, while the decrease in p-type layers is partly due to the increased impurity levels evolving from its doping, size effects play a primary role in limiting the thermal conductivity of GaN layers tens of microns thick. Device layers, even of pristine quality, will therefore exhibit thermal conductivities less than the bulk value of 240 W/mK owing to their finite thickness. Published by AIP Publishing.

引用

页数：6

共 67 条

[1]

[Anonymous], THESIS

[2] High spatial resolution thermal conductivity of lateral epitaxial overgrown GaN/sapphire (0001) using a scanning thermal microscope [J].