Investigation of Delta-Doped and Superlattice-Emitter Heterostructure Bipolar Transistors

• Main Authors: Shiou-Ying Cheng, 鄭岫盈
• Other Authors: Wen-Chau Liu
• Format: Others
• Language: en_US
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/64108555160704074743

博士 === 國立成功大學 === 電機工程學系 === 87 === In this dissertation, we pay attention on five delta-doped and superlattice-emitter heterostructure bipolar transistors. These novel structures included low-offset voltage high current gain In0.49Ga0.51P/GaAs delta-doped heterojunction bipolar transistor (D2HBT), In0.49Ga0.51P/GaAs double delta-doped heterojunction bipolar transistor (D3HBT), wide voltage operation regime In0.49Ga0.51P/GaAs double heterojunction bipolar transistor, Al0.48In0.52As/Ga0.47In0.53As superlattice-emitter resonant-tunneling bipolar transistor (SE-RTBT), and In0.49Ga0.51P/GaAs superlattice-emitter resonant-tunneling bipolar transistor (SE-RTBT) Chapter 1 is an introduction in this dissertation. For chapter 2 and 3, we investigate several key parameters to reduce the potential spike associated with conduction band discontinuity for conventional heterojunction. We demonstrate the qualitative influence of delta-doped sheet and setback layer on the performance of InGaP/GaAs heterojunction bipolar. Also, based on the theoretical analysis, the high-performance delta-doped heterojunction bipolar transistor and the improved double heterojunction bipolar transistors are fabricated and studied. These improved devices cannot only greatly reduce the magnitude of offset voltage, but also maintain relatively high emitter injection efficiency. In chapter 4, two superlattice-emitter resonant-tunneling bipolar transistor, based on AlInAs/GaInAs and InGaP/GaAs material systems, are fabricated and demonstrated. These functional structures not only significantly improve the transistor performance but also exhibit three-terminal controlled N-shaped negative-differential-resistance (NDR) characteristics. These interesting N-shaped NDR behavior are attributed primarily to RT through superlattice region. Chapter 5 is conclusion and prospect of this work.