Abstract
The effects of plasma pretreatment on sapphire and the properties of the GaN overgrown epilayers were investigated. The sapphire surface was pretreated with H2/N2 mixed gas-plasma at 350 °C for 30 min with fixed 50 W plasma power from which an about 2 nm thick oxygen-deficient layer was obtained. GaN epilayer of about 4.5 μm thick were grown using a metal organic chemical vapor deposition (MOCVD) system. X-ray rocking curves and cathodoluminescence spectra of the GaN epilayers showed that the crystallinity was improved through the mixed gas-plasma pretreatment of sapphire substrate. It was found that the oxygen-deficient thin layer plays a major role in reducing crytallographic defects in the GaN epilayers.
| Original language | English |
|---|---|
| Pages (from-to) | S446-S449 |
| Journal | Journal of the Korean Physical Society |
| Volume | 42 |
| Issue number | SPEC. |
| Publication status | Published - 2003 Feb |
| Event | Proceedings of The 11th Seoul International Symposium on the Physics of Semiconductors and Apllications - 2002 - Cheju Island, Korea, Republic of Duration: 2002 Aug 20 → 2002 Aug 23 |
Keywords
- GaN
- H/N mixed gas plasma
- Oxygen-deficient thin layer
ASJC Scopus subject areas
- Physics and Astronomy(all)