• 作者： 吳啟宗
• 作者服務機構： 交通大學電子工程系所
• 中文摘要： 半導體內自由載子吸收的量子原理，可引伸來處理限制自由載子在準二維半導體結構的問題，如N-型銻化銦薄膜。結果發現自由載子吸收係數與垂直於準二維結構之電磁輻射、光子頻率和溫度有關。本研究計算對於N-型銻化銦薄膜內因載子經由形變位能所產生之聲子散射吸收現象，這個吸收係數由於在半導體內導電子與輻射場及聲子場之作用，產生複素數值，當輻射場極化後沿垂直於薄膜層面時，自由載子吸收係數之虛數部份在低溫下將消失。
• 英文摘要： The quantum theory of free-carrier absorption in semiconductors is extended to treat the case wherethe free carriers are confined in a quasi-two-dimensional semiconducting structure such as n-type InSbfilms．The free-carrier absorption coefficient is found to depend upon the polarization of the electromagneticradiation relative to the direction normal to the quasi-two-dimensional structure, the thickness of the films,the photon frequency, and temperature. The free-carrier absorption coefficient in n-type InSb films hasbeen calculated for the case where the carriers are scattered by the acoustic-phonon via the deformation-potential coupling. The absorption coefficient could be a complex value due to the interaction of theradiation field and the phonon field with the conduction electrons in semiconductor films. However, whenthe radiation field is polarized perpendicular to the plane of the layer, the imaginary part of the free-carrierabsorption coefficient will vanish at low temperatures.
• 中文關鍵字： free-carrier absorption; quasi-two-dimensional semiconducting structure; deformation-potential coupling; radiation field; phonon field
• 英文關鍵字： --