Patent ID: 8884265

Claim:
An InGaAs n-channel quantum well heterostructure, comprising: a substrate; a first buffer layer disposed on the substrate, the first buffer layer being lattice-matched to the substrate; a second buffer layer disposed on the first buffer layer; a barrier layer disposed on the second buffer layer an In x Ga 1-x As, x=0.64 to 1, n-channel layer disposed on the second buffer layer, the In x Ga 1-x As n-channel material having a first lattice constant; a barrier layer disposed on the n-channel layer; a spacer layer disposed on the barrier layer; and a second barrier layer disposed on the spacer layer; wherein the heterostructure is configured for use with an antimonide-based p-channel material in a complementary transistor, the p-channel material having a second lattice constant different from the first lattice constant, a difference between the first and second lattice constants producing a strain between the n- and p-channels in the complementary transistor; wherein the second buffer layer serves as a buffer layer for both the n- and p-channels in the complementary transistor; and wherein the second buffer layer is configured to have a third lattice constant intermediate the first and second lattice constants and is configured to accommodate the strain produced by a lattice-constant mismatch between the n- and p-channels in the complementary transistor.