Improved thermal management for GaN power electronics: Silver diamond composite packages

A Review of Raman Thermography for Electronic and Opto-Electronic Device Measurement With Submicron Spatial and Nanosecond Temporal Resolution

“…For example, the benefit of replacing CuW with a silver-diamond composite is demonstrated by Raman thermography measurements performed in Ref. [89]. Alternatively, a flip-chip package can be used by attaching a high thermal conductivity heat spreader such as AlN to the top side of the device for heat extraction [43].…”

Low thermal resistance GaN-on-diamond transistors characterized by three-dimensional Raman thermography mapping

“…4 The role of the substrate as a heat spreader is particularly important because of its close proximity to the 2DEG conduction channel at the AlGaN/GaN interface, where Joule self-heating occurs. Silicon carbide has a relatively high thermal conductivity (up to j SiC % 420-490 W/mK) when compared to alternative substrate materials used for GaN epitaxy, for example silicon (j Silicon ¼ 140 W/mK).…”

“…In our analysis, a temperature dependent GaN layer thermal conductivity of 160 W/mK (T À1. 4 ) was used, consistent with previous work. [6][7][8]15,16 Based on the analysis of two devices, a thermal conductivity of 710 6 40 W/mK and GaN/diamond interfacial thermal resistance, of 2.7 6 0.3 Â 10 À8 m 2 K/W were obtained for wafer A, with opaque diamond and a 25 nm dielectric interlayer.…”

Diamond micro-Raman thermometers for accurate gate temperature measurements

“…5,6 Moreover, channel temperature measurement aids the improvement of thermal design for low thermal resistance. 7,8 In this Letter, we report a Raman-based technique to directly access the temperature of the gate contact in AlGaN/GaN HEMTs, utilizing diamond microparticles capable of monitoring gate temperature on timescales as short as 10 ls.…”