|학술대회||2014년 가을 (11/27 ~ 11/28, 대전컨벤션센터)|
|발표분야||A. 전자/반도체 재료(Electronic and Semiconductor Materials)|
|제목||Epiraxial growth of GaN on patterned sapphire substrate with AlN buffer layer.|
|초록||GaN (Gallium nitrid) is the most promising materials for the application of device such as LED. GaN has a direct band gap of 3.4eV at room temperature. However, GaN hetero-epitaxy grown on sapphire substrate leads to dislocation because of large lattice mismatch and thermal expansion coefficient mismatch between GaN and substrate (sapphire). Therefore low temperature GaN buffer layer on sapphire substrate was used to improve the structural property of GaN film. But, lattice mismatch still remains. Thus we need to alternative material with low lattice mismatch to replace low temperature GaN buffer layer.
In this study, AlN buffer layer with various thickness was grown on sapphire substrate. AlN buffer layer was deposited on sapphire substrate by Sputter system. GaN film was formed on pre-grown AlN buffer layer at 1020~1070 ℃, at 88~300torr by MOCVD. The morphology of GaN surface was investigated by Scanning Electron microscopy (SEM). Structural characteristic of GaN on PSS (Patterned Sapphire Substrate) using AlN buffer layer were evaluated by ω-2θ high resolution X-ray diffraction (HR-XRD).
The crystalline property of GaN film is improved by AlN buffer layer instead of GaN buffer layer. Also, PSS (Patterned Sapphire Substrate) is used to improve the internal luminance efficiency.
|저자||이지은, 김대식, 배선호, 정서주, 정우섭, 변동진|
|키워드||GaN; AlN; PSS; MOCVD; Crystalline|