Browsing by Author "Tsou, BC"

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Determining GaInP/GaAs HBT device structure by DC measurements on a two-emitter HBT device and high frequency transit time measurements
(2005-06-01)
Meng, CC
;
Tsou, BC
;
Tseng, SC
;
電信工程研究所
;
Institute of Communications Engineering
A method to monitor the GaInP/GaAs HBT device structure including emitter ledge thickness is demonstrated in this paper. The base thickness and base doping density are obtained through base transit time and base sheet resistance measurements while the base transit time is measured through the cut-off frequency measurements at various bias points. A large size two-emitter HBT device is used to measure the ledge thickness. Emitter doping profile and collector doping profile are obtained by the large size HBT device through C-V measurements. An FATFET device formed by two emitters as drain and source terminals and the interconnect metal as the on-ledge Schottky gate between two emitters is used to measure the ledge thickness.
The effect of selectively and fully ion-implanted collector on RF characteristics of BJT devices
(2006-04-01)
Meng, CC
;
Su, JY
;
Tsou, BC
;
Huang, GW
;
電信工程研究所
A selectively ion-implanted collector (SIC) is implemented in a 0.8 mu m BiCMOS process to improve the RF characteristics of the BJT devices. The SIC BJT device has better f(t) and f(max) than the FIC (fully ion-implanted collector) BJT device because the extrinsic base-collector capacitance is reduced by the SIC process. The f(t) is 7.8GHz and f(max) is 9.5 GHz for the SIC BJT device while the f(t) is 7.2 GHz and f(max) is 4.5 GHz for the FIC BJT device when biased at V-ce =3.6 V and J(c) = 0.07 mA/mu m(2). The noise parameters are the same for both BJT devices but the associated gain is higher for the SIC BJT device.