摘要
Crack free GaN films were grown on 1200×1200𝜈m^(2) patterned Si(111)substrates and 36 light emitting diodes(LEDs)were fabricated in each pattern unit.Spatial distribution of the tensile stress in the pattern units and its influence on the LED performance are studied by micro-Raman and electroluminescence(EL).The Raman shift of the GaN𝐹E_(2) mode shows that the tensile stress is the maximum at the center,partially relaxed at the edge,and further relaxed at the corner.With the stress relaxation,the EL wavelength has a significant blue shift and the luminous intensity shows a great enhancement.
基金
Supported by the National High-Technology Research and Development Program of China under Grant No 2011AA03A101
the National Natural Science Foundation of China under Grant No 51072076
the National Key Technology Research and Development Program of China under Grant No 2011BAE32B01.
