Microstructural characterization of high indium-composition InXGa₁-XN epilayers grown on c-plane sapphire substrates.
The growth of high-quality indium (In)-rich In(X)Ga(1-X)N alloys is technologically important for applications to attain highly efficient green light-emitting diodes and solar cells. However, phase separation and composition modulation in In-rich In(X )Ga(1-X)N alloys are inevitable phenomena that degrade the crystal quality of In-rich In(X)Ga(1-X)N layers. Composition modulations were observed in the In-rich In(X)Ga(1-X)N layers with various In compositions. The In composition modulation in the In X Ga1-X N alloys formed in samples with In compositions exceeding 47%. The misfit strain between the InGaN layer and the GaN buffer retarded the composition modulation, which resulted in the formation of modulated regions 100 nm above the In(0.67)Ga(0.33)N/GaN interface. The composition modulations were formed on the specific crystallographic planes of both the {0001} and {0114} planes of InGaN.
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea.
Myoungho
M
Jeong
Hyo Sung
HS
Lee
Seok Kyu
SK
Han
Eun-Jung-Shin
Soon-Ku
SK
Hong
Jeong Yong
JY
Lee
Yun Chang
YC
Park
Jun-Mo
JM
Yang
Takafumi
T
Yao