Patent ID: 7829912

Claim:
A semiconductor device with efficient carrier injection from a wide bandgap semiconductor material into a narrower bandgap semiconductor material, the semiconductor device comprising: a first semiconductor material having a desired bandgap; an injection structure adjacent the first semiconductor material, the injection structure comprising: a confining region formed from a second semiconductor material having a wider bandgap than the first semiconductor material; and a transition region positioned between the first and second semiconductor materials, the transition region comprising a first ramp portion in which a composition is gradually ramped and a doped intermediate structure, the doped intermediate structure having an inflection in the ramping of the composition wherein (i) the intermediate structure is n-doped and the electron affinity at the inflection is lower than the electron affinity of the confining region or (ii) the intermediate structure is p-doped and the hole affinity at the inflection is higher than the hole affinity of the confining region, wherein the ramping of the composition comprises a change in the content of Al, P, or Si and the change in content of the Al, P, or Si provides an electron affinity minimum or a hole affinity maximum within the ramping and the inflection occurs at an Al, P, or Si content that is within 20% of the electron affinity minimum or the hole affinity maximum.