Hole Transport and Optical Transition Properties in SiGe Alloys and Strained Quantum Wells

• Main Authors: Tsyr-Shyang Liou, 劉慈祥
• Other Authors: Chun-Yen Chang, Tahui Wang
• Format: Others
• Language: en_US
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/56772040055529774342

博士 === 國立交通大學 === 電子研究所 === 83 === In this thesis, three important research topics have been accomplished which include low-field and high-field hole trans- port characteristics in SiGe alloys, two-dimensional hole trans- port behaviors in SiGe/Si quantum wells,and optical transitional properties in SiGe/Si quantum structures.In order to high energy hole transport, a bond-orbital model is developed for the first time to calculate the band-structures in SiGe alloys. The depen- dence of low-field hole mobility in strained SiGe/Si(001) layers is calculated using a Monte Carlo technique.In addition,we study the high-field hole transport characteristics in strained SiGe alloys. With respect to the low-dimensional hole transport, the quantum confinement effects in the strained SiGe/Si quantum structures are investigated.The simulation results show that the 2D hole mobility increases with a well width in a SiGe/Si quantum well and converges to a saturated value of intrinsic SiGe alloy mobility.A study of infrared absorption due to intersubband tran- sitions in p-type SiGe/Si quantum wells has been also performed. By varying a well width, our study reveals that a maximum absorp- tion coefficient is achievable when the energy level of the excited- state subband is near the top of a quantum well.