Project/Area Number |
23656020
|
Research Category |
Grant-in-Aid for Challenging Exploratory Research
|
Allocation Type | Multi-year Fund |
Research Field |
Applied materials science/Crystal engineering
|
Research Institution | Kyushu University |
Principal Investigator |
TANAKA Satoru 九州大学, 工学研究院, 教授 (80281640)
|
Project Period (FY) |
2011 – 2012
|
Project Status |
Completed (Fiscal Year 2012)
|
Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2012: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Fiscal Year 2011: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
|
Keywords | エピタキシャル成長 / ワイドギャップ半導体 / 貫通転位 / III族窒化物 / 低転位化 / ポリタイプ / SiC / 選択成長 / 窒化物半導体 |
Research Abstract |
In-situRHEED and AFM at the initial growth stages indicate nucleation of 6H-GaN at the nanofacets followed by step-flow towards the vicinal direction [1-100] of the substrate. No nuclei on the terraces, generally resulting in 2H-polytype, are observed. Continuous growth under the same condition gives a ~50nm-thick GaN film to be analyzed by Raman and PL. Clear two zone-folded phonon modes are observed between E1(TO) and E2(high), which is indicative of the formation of 6H-polytype. The PL spectrum indicates different energy transitions from 2H-GaN: a peak at 3.33eV is shifted by -0.13eV, which also supports the formation of the 6H-polytype. This is due to the reduced bandgap in 6H-polytype, in agreement with theoretical predictions.
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