Title :
Hydrogen effects on reliability of GaAs MMICs
Author :
Camp, W.O., Jr. ; Lasater, R. ; Genova, V. ; Hume, R.
Author_Institution :
IBM Syst. Integration Div., Owego, NY, USA
Abstract :
Investigations into unexplained RF gain changes versus time during life tests have lead to the conclusion that hydrogen gas in quantities as small as 0.5% of ambient atmosphere can cause significant performance degradation in as little as 168 h at elevated temperatures (125 degrees C). This amount of hydrogen has been readily observed in Kovar hermetic packages with 0.1 cm/sup 3/ internal volume. The apparent mechanism for this degradation is the conversion of gaseous hydrogen into atomic hydrogen in Pt metallization, with subsequent doping compensation due to the atomic hydrogen. The loss of electron carriers leads directly to lower transconductance and lower RF gain. A change in the Schottky diode characteristics is also noted.<>
Keywords :
III-V semiconductors; MMIC; failure analysis; field effect integrated circuits; gallium arsenide; hydrogen; life testing; metallisation; microwave amplifiers; packaging; platinum; reliability; 125 C; 168 h; GaAs; GaAs MMICs; GaAs:H; H/sub 2/ effects; Kovar hermetic packages; Pt metallisation; RF gain changes; Schottky diode characteristics; doping compensation; elevated temperatures; failure mechanism; gain reduction; internal volume; life tests; loss of electron carriers; lower RF gain; lower transconductance; performance degradation; reliability; residual gas analysis; semiconductors; Atmosphere; Degradation; Gallium arsenide; Hydrogen; Life testing; MMICs; Packaging; Performance gain; Radio frequency; Temperature;
Conference_Titel :
Gallium Arsenide Integrated Circuit (GaAs IC) Symposium, 1989. Technical Digest 1989., 11th Annual
Conference_Location :
San Diego, CA, USA
DOI :
10.1109/GAAS.1989.69326
