Fabrication and simulation of Ga/sub 0.51/In/sub 0.49/P/In/sub x/Ga/sub 1-x/As doped-channel FETs and MMIC amplifiers grown by GSMBE

The first Ga/sub 0.51/In/sub 0.49/P/In/sub x/Ga/sub 1-x/As (0/spl les/x/spl les/0.22) doped-channel FETs (DCFETs) grown by GSMBE exhibiting excellent dc and microwave characteristics were successfully fabricated. A high g/sub m/ of 400 mS/mm, a high f/sub t/ of 47 GHz, and a high f/sub max/ of 94 GHz were achieved at 300 K for a Ga/sub 0.51/In/sub 0.49/P/In/sub 0.15/Ga/sub 0.85/As DCFET with a 0.5 /spl mu/m-long gate. The device also showed a very high maximum current density (650 mA/mm) and a very high gate-to-drain breakdown voltage (31 V). The first MMIC local drive amplifier (LDA) using Ga/sub 0.51/In/sub 0.49/P/In/sub x/Ga/sub 1-x/As DCFET with x=0 as active component was successfully fabricated and exhibited excellent input and output VSWRs. The measured input and output VSWRs at central frequency were 1.19 and 1.12, respectively and were very consistent with the simulated results. The measured and simulated S parameters of this amplifier agreed very well. All these results indicate the great potential of using Ga/sub 0.51/In/sub 0.49/P/In/sub x/Ga/sub 1-x/As DCFETs for microwave integrated circuit application.