| Autor: |
Yusuke Kumazaki, Keisuke Uemura, Taketomo Sato, Tamotsu Hashizume |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2017, Vol. 121 Issue 18, p1-6, 6p, 1 Diagram, 8 Graphs |
| Abstrakt: |
The photocarrier-regulated electrochemical (PREC) process was developed for fabricating recessed-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) for normally off operation. The PREC process is based on photo-assisted electrochemical etching using low-energy chemical reactions. The fundamental photo-electrochemical measurements on AlGaN/GaN heterostructures revealed that the photo-carriers generated in the top AlGaN layer caused homogeneous etching of AlGaN with a smooth surface, but those generated in the GaN layer underneath caused inhomogeneous etching that roughens the surface. The concept of the PREC process is to supply the photocarriers generated only in the AlGaN layer by selecting proper conditions on light wavelength and voltage. The phenomenon of self-termination etching has been observed during the PREC process, where the etching depth was controlled by light intensity. The recessed-gate AlGaN/GaN HEMT fabricated with the PREC process showed positive threshold voltage and improvement in transconductance compared to planar-gate AlGaN/GaN HEMTs. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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