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Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
Published on: July 17, 2020
Strain induced bandgap and refractive index variation of silicon
Jingnan Cai1, Yasuhiko Ishikawa, Kazumi Wada
1Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo,113-8656, Japan. cai@microphotonics.t.u-tokyo.ac.jp
Abstract:
We present a study of the influence of high strain on the bandgap and the refractive index of silicon. The results of photoluminescence show that with the strain applied, the silicon bandgap can be adjusted to 0.84 eV and the refractive index of silicon increases significantly. 1.4% change of refractive index of silicon was observed. The strain-induced bandgap shrinkage and absorption coefficient change of silicon are considered as the main cause of the significant refractive index change. The present work indicates that the application of strain is promising to control the refractive index of silicon in devices so that applications such as compensation of thermal effect in optical devices can be achieved.
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