Diamond Integration on GaN for Channel Temperature Reduction

At a Glance

Metadata	Details
Publication Date	2021-11-07
Authors	Mohamadali Malakoutian, Runjie Lily Xu, Chenhao Ren, Shubhra S. Pasayat, Islam Sayed
Institutions	Stanford University, University of California, Santa Barbara
Citations	4

Abstract

GaN-based transistors offers the highest power density for radio-frequency (RF) applications. However, self-heating significantly limits device performance and reliability that must be managed for the transistors to perform. Exploiting the high thermal conductivity of polycrystalline diamond (300-2000 Wm <sup xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>-1</sup> K <sup xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>-1</sup> near room temperature), we have demonstrated polycrystalline diamond integration on top of the GaN channels for effective device cooling, while preserving its electrical performance. Various thicknesses of polycrystalline diamond were grown on top of the GaN channel to investigate its impact on the device temperature. Using Raman thermometry, a remarkably lower temperature (by 30-60 °C) was measured in the channel for devices with diamond compared to control devices without diamond. The effect of diamond thickness (250-650 nm) and device layout on the heat dissipation was carefully studied and discussed. We have shown that thicker diamond (~650 nm) along with the metal-diamond overlap improves channel cooling capabilities of the diamond heat spreader by a factor of two.

Tech Support

Original Source

DOI: https://doi.org/10.1109/wipda49284.2021.9645133

References

2019 - A study on the nucleation and MPCVD growth of thin, dense, and contiguous nanocrystalline diamond films on bare and Si3N4-coated N-polar GaN
2014 - Reduction of the thermal conductivity in freestanding silicon nano-membranes investigated by non-invasive Raman thermometry [Crossref]