Dept. of Electr. Eng., National Taiwan Univ.Tsai, M.K.M.K.TsaiWu, Y.W.Y.W.WuTan, S.W.S.W.TanChu, M.Y.M.Y.ChuChen, W.T.W.T.ChenYang, Y.J.Y.J.YangLour, W.S.W.S.LourYING-JAY YANG2018-09-102018-09-102002-10http://scholars.lib.ntu.edu.tw/handle/123456789/299390https://www.scopus.com/inward/record.uri?eid=2-s2.0-84952651553&doi=10.1109%2fCOMMAD.2002.1237272&partnerID=40&md5=6e9f8d850f03e3f0d02cc12794fc6d5cThis paper reported a new composite-emitter heterojunction bipolar transistor (CEHBT) with a composite emitter formed of a 0.04μm In0.5Ga0.5P bulk layer and a 0.06μm AI045Ga0.55As/GaAs digital graded superlattice (DGSL) layer. The CEHBT's exhibit a small collector-emitter offset voltage of 55 mV and a base-emitter turn-on voltage of 0.87 V, which is 0.4 V lower than that of 1.27 V of the InGaP/AlGaAs abrupt-emitter HBT. It is found that CEHBTs exhibits a current gain as high as 250 and is even enhanced to 385 when only a DGSL layer is used for passivation layer. © 2002 IEEE.application/pdf177690 bytesapplication/pdf[SDGs]SDG7Amplification; Gallium; Heterojunctions; Microelectronics; Base emitters; Collector emitters; Composite emitters; Current gains; Passivation layer; Turn-on voltages; Heterojunction bipolar transistorsconference paper10.1109/COMMAD.2002.12372722-s2.0-84952651553