Raman spectroscopic study of ZnO surface

• Main Author: Guo, Qiongyao.
• Other Authors: Sun Changqing
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Microelectronics
• Online Access: http://hdl.handle.net/10356/49807
• Institution: Nanyang Technological University

The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy 60 meV which could lead to lasing action based on exciton recombination even above room temperature. [1] In this study, Raman spectroscope will be used to examine the lattice vibration of ZnO crystals under applied temperature to understand the physical origin behind the frequency change from the perspective of interatomic interaction between under coordinated atoms in the surface region. Raman spectroscope observed 3 modes (A1 (LO), E2 (Low), and E2 (High)) because the incident light is exactly normal to the surface, the other modes are forbidden according to the Raman selection rules. These 3 Raman frequencies of ZnO will shift due to the change in temperature because of the bond expansion and bond weakening due to vibration.