SUBJECT: M.S. Thesis Presentation
BY: Kirkland Malcolm
TIME: Tuesday, April 19, 2016, 9:30 a.m.
PLACE: Love Building, 295
TITLE: Characterization of the Thermal Properties of Chemical Vapor Deposition Grown Diamond Films for Electronics Cooling
COMMITTEE: Dr. Samuel Graham, Chair (ME)
Dr. Satish Kumar (ME)
Dr. Tequila Harris (ME)


CVD Diamond is a promising technology for the passive cooling of high power GaN semiconductor devices. The high thermal conductivity diamond can be placed near the junction of the GaN transistor either by direct growth on the backside of the GaN or through bonding it to the GaN. In both cases, the thermal resistance near the interface with the diamond and any semiconductor it is attached to has the potential for large thermal resistance that limits the effectiveness of the diamond layer.

In this work, several techniques are developed to understand the thermal conductivity of thin nano crystalline diamond films and the thermal boundary resistance with Si and GaN substrates. Anisotropic thermal conductivity measurements are made using Raman spectroscopy temperature mapping along with electric resistance heating. For devices, the thermal boundary resistance is measured using transistors as the heat source and thermal mapping using Raman spectroscopy. Quick screening methods based on Raman and FTIR are also correlated with the thermal properties of the films. Based on this work, the properties of CVD diamond films near the interface of semiconductor substrates is revealed for layers less than 5 ┬Ám in thickness and their impact or limitations on thermal management shown through simulations.