Title :
SiGe heterojunction bipolar transistors with thin alpha -Si emitters
Author :
Tang, Z.R. ; Kamins, Theodore ; Li, P. ; Salama, C.A.T.
Author_Institution :
Dept. of Electr. & Comput. Eng., Toronto Univ., Ont., Canada
Abstract :
A SiGe-base heterojunction bipolar transistor with an extremely thin n hydrogenated amorphous Si ( alpha -Si:H) emitter is proposed and characterized. The structure results in enhanced emitter injection efficiency, current gain, and frequency performance. The fabricated devices exhibited maximum current gains of 100 and Early voltages of 55 V. The unity current gain cutoff frequency (f/sub T/) for a device with an emitter size of 2 mu m*4 mu m was 8.5 GHz.<>
Keywords :
Ge-Si alloys; heterojunction bipolar transistors; hydrogen; semiconductor materials; silicon; solid-state microwave devices; thermionic emission; 55 V; 8.5 GHz; Early voltages; HBT; SiGe-Si:H; amorphous Si; current gain; emitter injection efficiency; frequency performance; heterojunction bipolar transistors; thin alpha -Si emitters; unity current gain cutoff frequency; Amorphous materials; Current density; Electrons; Germanium silicon alloys; Heterojunction bipolar transistors; Performance gain; Photonic band gap; Silicon germanium; Temperature; Thermionic emission;
Journal_Title :
Electron Device Letters, IEEE
