Impact of subchannel design on DC and RF performance of 0.1 μm MODFETs with InAs-inserted channel

It is shown that a further performance improvement in MODFETs with InAs-inserted channel structures can be achieved by properly designing the subchannel layer that lies directly under the main channel of the InAs layer. The use of an In/sub 0.30/Ga/sub 0.70/As layer grown with tensile strain on the InP substrate contributes to better accommodation of the 2D electron gas in the InAs layer. This translates to a >10% increase in the maximum extrinsic transconductance and an 8% increase in the current gain cutoff frequency of a 0.1 /spl mu/m device.