Title :
Digital etching for highly reproducible low damage gate recessing on AlGaN/GaN HEMTs
Author :
Buttari, D. ; Heikman, S. ; Keller, S. ; Mishra, U.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
Abstract :
A room temperature digital etching technique for aluminum gallium nitride has been developed. An oxidizing agent and an acid have been used in a two step etching cycle to remove aluminum gallium nitride in approximately 5-6 Å increments. The process has been characterized to be reasonably linear and highly repeatable, offering an alternative to currently not available gate recess etch stopper technologies. Recessed gate Al0.35Ga0.65N/GaN HEMTs on sapphire were compared to unrecessed devices realized on the same sample. A fivefold gate leakage decrease and negligible variations on breakdown voltage support digital recessing as a viable solution for highly reproducible low surface-damage gate recessed structures.
Keywords :
III-V semiconductors; aluminium compounds; etching; gallium compounds; high electron mobility transistors; leakage currents; semiconductor device breakdown; semiconductor device reliability; wide band gap semiconductors; 5 to 6 Å; Al0.35Ga0.65N-GaN; AlGaN/GaN; HEMTs; breakdown voltage; gate leakage; gate recessing; oxidizing agent; room temperature digital etching technique; two step etching cycle; unrecessed devices; Aluminum gallium nitride; Dry etching; Gallium nitride; Gate leakage; HEMTs; MODFETs; Plasma applications; Plasma measurements; Reproducibility of results; Wet etching;
Conference_Titel :
High Performance Devices, 2002. Proceedings. IEEE Lester Eastman Conference on
Print_ISBN :
0-7803-7478-9
DOI :
10.1109/LECHPD.2002.1146788
