Abstract
A method for highly controllable etching of AlGaN/GaN for the fabrication of high sensitivity HEMT based sensors is developed. The process consists of cyclic oxidation of nitride with O2 plasma using ICP-RIE etcher followed by wet etching of the oxidized layer. Previously reported cyclic oxidation-based GaN etching obtained very slow etching rate (∼0.38nm/cycle), limited by oxidation depth. The proposed approach allows fine control of the oxidation enabling the formation of accurately controlled recess of very thin (20∼30nm) barrier layers. With optimized power settings, etch rates from ∼0.6 to ∼11nm/cycle were obtained. AFM results did not show any increase in surface roughness after etching, indicating that surface quality of the etched layer was not affected by the etching process.
Original language | English |
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Pages (from-to) | 1094-1097 |
Number of pages | 4 |
Journal | Procedia Engineering |
Volume | 168 |
DOIs | |
Publication status | Published - 2016 |
Event | Eurosensors 2016: The 30th anniversary Eurosensors Conference - Budapest, Hungary Duration: 4 Sept 2016 → 7 Sept 2016 |
Keywords
- AlGaN/GaN
- cyclic etch
- gate recess
- HEMT
- HEMT-sensor
- ICP-RIE
- plasma oxidation
- semiconductor sensor