Title :
1/f noise of AlGaAs-GaAs HBTs controlled by biasing an on-ledge Schottky diode
Author :
Ma, Pingxi ; Zampardi, Peter ; Chang, M.F. ; Sheu, Jerry ; Li, G.P.
Author_Institution :
Dept. of Electr. Eng., California Univ., Los Angeles, CA, USA
Abstract :
Experimental results indicate that the 1/f noise spectral density of HBTs is strongly influenced by the emitter ledge potential. By biasing an on-ledge Schottky diode, we can externally control the ledge potential and alter an HBT´s 1/f noise spectral density and its dependence on the base current. When biasing the on-ledge diode at VL<VBE, HBT 1/f noise spectral densities are found to increase dramatically (up to 30 dB) from the unbiased value and exhibit stronger dependence on IB (from IB1.42 to IB1.84). When biasing the on-ledge diode at VL>VBE, the HBT 1/f noise spectral density is found to decrease (about 10 dB) and exhibit virtually no dependence on IB (from IB1.42 to IB0.18). These findings help us identify the sources of the 1/f noise and create a novel 4-terminal HBT (with an extra ledge electrode) for extremely low 1/f noise RF transceiver applications
Keywords :
1/f noise; III-V semiconductors; Schottky diodes; UHF bipolar transistors; aluminium compounds; gallium arsenide; heterojunction bipolar transistors; interference suppression; semiconductor device measurement; semiconductor device noise; transceivers; 1/f noise; 1/f noise sources; AlGaAs-GaAs; AlGaAs-GaAs HBTs; HBT 1/f noise spectral density; base current; emitter ledge potential; extremely low 1/f noise RF transceiver applications; four-terminal HBT; ledge electrode; ledge potential; on-ledge Schottky diode; on-ledge Schottky diode biasing; on-ledge diode; Density measurement; Gallium arsenide; Heterojunction bipolar transistors; Integrated circuit noise; Noise level; Noise measurement; Passivation; Schottky diodes; Semiconductor device noise; Transceivers;
Conference_Titel :
Bipolar/BiCMOS Circuits and Technology Meeting, 2000. Proceedings of the 2000
Conference_Location :
Minneapolis, MN
Print_ISBN :
0-7803-6384-1
DOI :
10.1109/BIPOL.2000.886207