Two layer stepped-QW channel HFETs on InP-substrate

A novel HFET structure on InP containing an asymmetric two layer stepped QW channel sandwiched between two InAlAs barriers is proposed. A small bandgap InGaAs channel hosts the 2DEG-density and provides a low sheet resistance at low drain field. A higher bandgap sub channel of (a) InP and (b) InGaAs/InAlAs superlattice is designed to act as high field drift layer. This approach allows to obtain high f/sub maxf/sub t/-ratios and high output power at high speed. First results are given.<
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