The character of δ-doping in InGaP/InGaAsN/GaAs HBT wafer by photo-reflectance technique

• Main Authors: Lin Chun Hung, 林俊宏
• Other Authors: Yee-Shyi Chang
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/45726352686249273044

碩士 === 國立清華大學 === 材料科學工程學系 === 91 === We use the photo-reflectance (PR) technique to measurements InGaP/InGaAsN/GaAs heterojunction bipolar transistor (HBT) wafer , we fine the change of photo-reflectance spectrum when there is a high concentration δ-doping layer added in our sample ,and we can obtained electric field、energy gap in thecollector/base、emitter/base by Franz-Keldysh oscillations (FKOs) from photo-reflectance spectrum . In this experiment , the waferwith δ-doping layer will be have a special PR spectrum and theelectric field are more higher then others . This kind of sample cannot become a good-condition device and their current gain equal 1 . To analysis this special phenomenal , we etching our sample and use photo-reflectance technique . After analysis every layer of sample , we provide that the special phenomenal when the wafer hasδ-doping layer . In this thesis , we guess it was form by the diffusion between epitaxial layer .