Epitaxial growth of group iii nitrides on silicon substrates via a reflective lattice-matched zirconium diboride buffer layer

Abstract

A semiconductor structure and fabrication method is provided for integrating wide bandgap nitrides with silicon. The structure includes a substrate, a single crystal buffer layer formed by epitaxy over the substrate and a group III nitride film formed by epitaxy over the buffer layer. The buffer layer is reflective and conductive. The buffer layer may comprise B an element selected from the group consisting of Zr, Hf, Al. For example, the buffer layer may comprise ZrB, AlBor HfB. The buffer layer provides a lattice match with the group III nitride layer. The substrate can comprise silicon, silicon carbide (SiC), gallium arsenide (GaAs), sapphire or AlO. The group III nitride material includes GaN, AlN, InN, AlGaN, InGaN or AlInGaN and can form an active region. In a presently preferred embodiment, the buffer layer is ZrBand the substrate is Si(111) or Si(100) and the group III nitride layer comprises GaN. The ZrBbuffer layer provides a reflective and conductive buffer layer that has a small lattice mismatch with GaN. The semiconductor structure can be used to fabricate active microelectronic devices, such as transistors including field effect transistors and bipolar transistors. The semiconductor structure also can be used to fabricate optoelectronic devices, such as laser diodes and light emitting diodes.