Preparation and Characterization of GaN-on-Si HEMTs with Nanocrystalline Diamond Passivation
Year: 2025
Type: article
Abstract: Thermal accumulation under high output power densities is one of the most significant challenges for GaN power devices. Diamond, with its ultra-high thermal conductivity, offers great potential for improving heat dissipation in high-power GaN devices. In this study, nanocrystalline diamond (NCD) passivated high-electron mobility transistors (HEMTs) based on AlGaN/GaN-on-Si heterostructures were fabricated with a gate length of 2 μm. The NCD film has a thickness of 250–383 nm and a uniform morphology with a grain size of mostly ~240 nm. Compared to the devices without NCD passivation, those devices with the NCD passivation layer show an increase in current density from 447 mA/mm to 555 mA/mm, a reduction in on-resistance from 20 Ω·mm to 13 Ω·mm, and a noticeable suppression of current degradation at high-drain voltages. Junction temperature measurements under varied output power densities reveal a 36% improvement in heat dissipation efficiency with the NCD passivation. These results fully demonstrate the promising potential of NCD for enhancing heat dissipation in high-power GaN devices.
Source: Crystals
Institution: Xidian University
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,534
Awards: G1603751032, G1751504635, G199601662, G2189610905, G2269836297, G2413327175, G2479180562, G2553194765, G2687236760, G2720027244, G280808964, G3434183261, G3500277608, G4006247492, G42693585, G450442871, G4621970335, G4993283811, G5435439777, G5481241115, G5698204627, G5782892680, G5887813918, G5955355093, G6898292503, G6915689102, G772719135, G7858363136, G8208353505, G8424903982, G8906779247
OpenAlex ID: W4408089976