Ultra-thin AlGaN/GaN HFET with a high breakdown voltage on sapphire substrates

In this Letter, an ultra-thin AlGaN/GaN heterostructure field effect transistor (HFET) with a total thickness of similar to 200nm was fabricated on sapphire substrates by combing physical vapor deposition and metal organic chemical vapor deposition growth methods. Thanks to the absence of a conventional semi-insulating thick GaN buffer by taking advantage of an ex situ sputtered AlN nucleation layer, we achieved a profound soft breakdown voltage of 1700V accompanied by a 12.5 Omega.mm on-resistance and a low off-state leakage of 0.1 mu A/mm in such ultra-thin HFET devices. Our work demonstrates an alternative strategy to fabricate GaN based power devices with high breakdown voltage and low cost. Published under an exclusive license by AIP Publishing.

Automated summary

In this study, an ultra-thin AlGaN/GaN heterostructure field effect transistor (HFET) was fabricated with high breakdown voltage, low on-resistance, and low off-state leakage by using an innovative ex situ sputtered AlN nucleation layer method. This work demonstrates an alternative strategy for fabricating GaN-based power devices with high performance at a low cost.