Title :
High efficiency AlGaAs/GaAs power HBTs at a low supply voltage for digital cellular phones
Author :
Miura, T. ; Shimura, T. ; Mori, K. ; Uneme, Y. ; Nakano, H. ; Inoue, A. ; Hattori, R. ; Tanino, N.
Author_Institution :
Optoelectron. & Microwave Devices Lab., Mitsubishi Electr. Corp., Hyogo, Japan
Abstract :
We present a high performance AlGaAs/GaAs power HBT with very low thermal resistance for digital cellular phones. Device structure with emitter air-bridge is utilized and device layout is optimized to reduce thermal resistance by three-dimensional thermal flow analysis, and in spite of a rather thick substrate (100 /spl mu/m), a low thermal resistance of 23/spl deg/C/W is achieved for a multi-finger (4/spl times/40 /spl mu/m/sup 2//spl times/40 fingers) HBT. This 40 finger HBT achieved power added efficiency (PAE) of over 53%, 29.1 dBm output power (Pout) and high associated gain (Ga) of 13.5 dB with 50 KHz adjacent channel leakage power (Padj) of less than 48 dBc under a 948 MHz /spl pi//4-shifted QPSK modulation with 3.4 V emitter-collector voltage.
Keywords :
III-V semiconductors; aluminium compounds; cellular radio; digital radio; gallium arsenide; heterojunction bipolar transistors; land mobile radio; power bipolar transistors; telephone sets; thermal resistance; /spl pi//4-shifted QPSK modulation; 13.5 dB; 3.4 V; 53 percent; AlGaAs-GaAs; AlGaAs/GaAs power HBT; adjacent channel leakage power; digital cellular phone; emitter air-bridge; gain; low voltage operation; multi-finger HBT; output power; power added efficiency; thermal resistance; three-dimensional thermal flow analysis; Assembly; Cellular phones; Electric resistance; Fabrication; Fingers; Gallium arsenide; Heterojunction bipolar transistors; Low voltage; Temperature; Thermal resistance;
Conference_Titel :
Gallium Arsenide Integrated Circuit (GaAs IC) Symposium, 1996. Technical Digest 1996., 18th Annual
Conference_Location :
Orlando, FL, USA
Print_ISBN :
0-7803-3504-X
DOI :
10.1109/GAAS.1996.567746
