화학공학소재연구정보센터
Applied Surface Science, Vol.257, No.21, 8846-8849, 2011
The testing of stress-sensitivity in heteroepitaxy GaN/Si by Raman spectroscopy
In this paper the stress-sensitive features of hexagonal-GaN (H-GaN) and cubic-Si (C-Si) were investigeted. The H-GaN films have been grown on Si (1 1 1) substrates by metal-organic chemical vapor deposition (MOCVD). The Raman peaks of GaN E-2 (high) and Si (TO) have a blueshift when applying displacement-loadings which parallel the (0 0 0 2) plane of H-GaN. According to the relationship between stress changing and Raman peak shifts, the values of compressive stress in both materials were larger with increasing the displacement-loadings. The stress-sensitivity of H-GaN up to 93.5 MPa/mu m which higher than C-Si which testing is 467.9 MPa/mu m and the nonlinear error sigma of GaN films is 0.1639 and Si is 0.0698. The measurement has a great significance to deeply research the piezoelectric polarization of H-GaN in future. This finding is important for the understanding and application of nitride semiconductors. (C) 2011 Elsevier B. V. All rights reserved.