Study of the Modulated Spectra in GaAs/InGaAs Heterostructure

• Main Authors: Sue, Shing-Jane, 蘇素珍
• Other Authors: Lu Chien-Rong
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/10758682445348306253

碩士 === 國立臺灣師範大學 === 物理學系 === 84 === The varities of built-in fields of the MBE grown GaAs/InGaAs heterostructures have been studied by the photoreflectance spectroscopy(PR) at various temperature.The spectra were complicated and contained four types of oscillations in different spectra regions.The origins of different features in the spectra were identified by comparing lineshape fitting and analysis with experiment result of appling bias voltage on sample. Above the energy gap of GaAs,there were two types of spectra oscillations. The one with large oscillatin period was due to the modulation of the high built-in field in second layer.The lineshape oscillations above the energy gap of InGaAs originated from first and third layers which were both n-type doped. The built-in fields were deduced from the spectra fitting and analysis,and compared with the numerically calculated results.