[18p-PA6-1~30] 13.7 Compound and power electron devices and process technology

[18p-PA6-10] Effect of selective dryetching on performances of p-GaN gate AlGaN/GaN high electron mobility transistor

〇(M1)Takaaki Kondou¹, Yoshihiko Akazawa¹, Naotaka Iwata¹ (1.Toyota Tech. Inst)

Keywords:GaN, HEMT, Dry etching

We reported the p-type GaN gate AlGaN/GaN HEMT in the previous conference. The gate is formed by selective dry etching. To remove unnecessary p-type layer, excessive time is required. However, unexpected problems such as thinning of the AlGaN layer and defect formation in it might be occurred. In this study, we have investigated the effect of dry etching on HEMT performances. Samples which was etched for 10 minutes and 30 seconds, and was etched for 20minutes and 30seconds were fabricated, and the characteristics were evaluated. By over-etching, the on-resistance was found to increase from 7.0 to 8.8 Ωmm. The electron mobility in the etching region decreased from 1600 to 1100 cm²/Vs. The increase of the on-resistance is assumed to be caused by the decrease of the electron mobility.