Depletion mode HEMT with refractory metal silicide WSi gate has been designed and fabricated. Epitaxial modulation doping materials were grown by a home-made MBE system. The gate length and width for low noise depleti...Depletion mode HEMT with refractory metal silicide WSi gate has been designed and fabricated. Epitaxial modulation doping materials were grown by a home-made MBE system. The gate length and width for low noise depletion devices were 1.2-1.5 μm and 2 × 160 μm respectively. The electron mobility of the fabricated devices is typically 6 080 cm2/V.s at 300K and 68 000 cm2/V.s at 77K. The sheet electron concentration ns is 9 × 10 11 cm-2. The source-drain contacts with AuGeNi/Au were fabricated using evaporating and lift-off technique. to further reduce the contact resistance, the wafer was alloyed at 520 ℃ for 3 min in the hydrogen (H2) gas. Schottky gate was formed using WSi. The transconductance of the depletion mode device is 110～130 mS/mm at room temperature. The devices can be applied in communication satellite at microwave frequency of 3. 83 GHz and radar receiver at 1. 5 GHz. Its noise figure is about 2～3 dB.展开更多
文摘Depletion mode HEMT with refractory metal silicide WSi gate has been designed and fabricated. Epitaxial modulation doping materials were grown by a home-made MBE system. The gate length and width for low noise depletion devices were 1.2-1.5 μm and 2 × 160 μm respectively. The electron mobility of the fabricated devices is typically 6 080 cm2/V.s at 300K and 68 000 cm2/V.s at 77K. The sheet electron concentration ns is 9 × 10 11 cm-2. The source-drain contacts with AuGeNi/Au were fabricated using evaporating and lift-off technique. to further reduce the contact resistance, the wafer was alloyed at 520 ℃ for 3 min in the hydrogen (H2) gas. Schottky gate was formed using WSi. The transconductance of the depletion mode device is 110～130 mS/mm at room temperature. The devices can be applied in communication satellite at microwave frequency of 3. 83 GHz and radar receiver at 1. 5 GHz. Its noise figure is about 2～3 dB.
