Performance of GaAs MESFET's on InP substrates

The fabrication of GaAs MESFET's with 0.9- mu m gate length on InP substrates, after growth of the heteroepitaxial material by metalorganic chemical vapor deposition (MOCVD) is described. The MESFETs exhibit extrinsic transconductances of 377 mS-mm/sup -1/, the highest value yet reported for GaAs-on-InP devices. The drain I-V characteristic shows excellent saturation, a knee voltage of 0.75 V, and no light sensitivity. A unity current-gain cutoff frequency of 22 GHz and a maximum frequency of oscillation of 30 GHz are obtained for these MESFETs.<
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