Open AccessSelectively dry etched of p-GaN/InAlN heterostructures using BCI3-based plasma for normally-off HEMT technology
Author(s) -
Ahmet Toprak,
Doğan Yılmaz,
Ekmel Özbay
Publication year - 2021
Publication title -
materials research express
Language(s) - English
Resource type - Journals
ISSN - 2053-1591
DOI - 10.1088/2053-1591/ac3e98
Subject(s) - materials science , high electron mobility transistor , etching (microfabrication) , inductively coupled plasma , plasma , surface roughness , optoelectronics , dry etching , reactive ion etching , surface finish , atomic force microscopy , plasma etching , heterojunction , root mean square , analytical chemistry (journal) , nanotechnology , layer (electronics) , composite material , transistor , chemistry , electrical engineering , physics , voltage , quantum mechanics , chromatography , engineering
In this paper, an alternative selective dry etching of p-GaN over InAlN was studied as a function of the ICP source powers, RF chuck powers and process pressures by using inductively coupled plasma reactive ion etching (ICP RIE) system. A recipe using only BCI 3 -based plasma with a resulting selectivity 13.5 for p-GaN in respect to InAlN was demonstrated. Surface roughness measurements depending on the etching time was performed by atomic force microscope (AFM) measurement and showed that a smooth etched surface with the root-mean-square roughness of 0.45 nm for p-GaN and 0.37 nm for InAlN were achieved. Normally-off p-GaN/InAlN HEMT devices were fabricated and tested by using the BCI 3 -based plasma we developed.