Title :
Reduction of low-frequency noise in a DC-2.5 GHz GaAs amplifier
Author :
Chen, C.Y. ; Bayruns, J. ; Bayruns, R.J. ; Scheinberg, N.
Author_Institution :
ANADIGICS Inc., Warren, NJ, USA
Abstract :
The low-frequency noise of a monolithic GaAs DC-2.5 GHz amplifier has been investigated in the frequency band of 100 Hz-1 MHz. As much as 8-10 dB reduction in noise power (for 100 Hz-10 kHz) has been achieved through the use of a buffer layer grown by MOCVD (metalorganic chemical vapor deposition). The amplifiers fabricated on horizontal bridgman (HB) wafer also offer an improvement of approximately 5 dB (in the frequency band of 100 Hz-4 kHz) as compared to undoped LED (liquid-encapsulated Czochralski) substrates. More importantly, the amplifiers made on MOCVD buffer substrates and HB wafers do not show low-frequency oscillations within the bias range, while those fabricated on undoped LEC and light Cr-doped LEC substrates exhibit coherent oscillations.<>
Keywords :
III-V semiconductors; MMIC; electron device noise; field effect integrated circuits; gallium arsenide; microwave amplifiers; ultra-high-frequency amplifiers; wideband amplifiers; 0 to 2.5 GHz; 100 Hz to 1 MHz; 2.5 GHz; GaAs; III-V semiconductors; LF noise reduction; MMIC; MOCVD; UHF; buffer layer; low-frequency noise; metalorganic chemical vapor deposition; microwave frequencies; monolithic wideband amplifier; Buffer layers; Electron traps; Feedback; Frequency; Gallium arsenide; Low-frequency noise; Low-noise amplifiers; MESFETs; MOCVD; Noise reduction;
Conference_Titel :
Gallium Arsenide Integrated Circuit (GaAs IC) Symposium, 1988. Technical Digest 1988., 10th Annual IEEE
Conference_Location :
Nashville, Tennessee, USA
DOI :
10.1109/GAAS.1988.11078
