Transition from Screw-Type to Edge-Type Misfit Dislocations at InGaN/GaN Heterointerfaces
Quantong Li,
Albert Minj,
Yunzhi Ling,
Changan Wang,
Siliang He,
Xiaoming Ge,
Chenguang He,
Chan Guo,
Jiantai Wang,
Yuan Bao,
Zhuming Liu,
Pierre Ruterana
Affiliations
Quantong Li
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Albert Minj
Interuniversity Microelectronics Centre (IMEC), Kapeldreef 75, 3000 Leuven, Belgium
Yunzhi Ling
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Changan Wang
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Siliang He
Key Laboratory of Microelectronic Packaging & Assembly Technology of Guangxi Education Department, School of Mechanical & Electrical Engineering, Guilin University of Electronic Technology, Guilin 541004, China
Xiaoming Ge
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Chenguang He
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Chan Guo
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Jiantai Wang
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Yuan Bao
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Zhuming Liu
Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China
Pierre Ruterana
CIMAP UMR 6252, CNRS ENSICAEN UCBN CEA, 6 Boulevard du Maréchal Juin, 14050 Caen, France
We have investigated the interface dislocations in InxGa1−xN/GaN heterostructures (0 ≤ x ≤ 0.20) using diffraction contrast analysis in a transmission electron microscope. The results indicate that the structural properties of interface dislocations depend on the indium composition. For lower indium composition (up to x = 0.09), we observed that the screw-type dislocations and dislocation half-loops occurred at the interface, even though the former do not contribute toward elastic relaxation of the misfit strain in the InGaN layer. With the increase in indium composition (0.13 ≤ x ≤ 0.17), in addition to the network of screw-type dislocations, edge-type misfit dislocations were generated, with their density gradually increasing. For higher indium composition (0.18 ≤ x ≤ 0.20), all of the interface dislocations are transformed into a network of straight misfit dislocations along the direction, leading to partial relaxation of the InGaN epilayer. The presence of dislocation half-loops may be explained by a slip on basal plane; formation of edge-type misfit dislocations are attributed to punch-out mechanism.
