| 摘要 |
A spinel composition of the invention includes a monocrystalline lattice having a formula Mg1-w.alpha.wA1x-y.beta.yOz, where w is greater than 0 and less than 1, x is greater than 2 and less than about 8, y is less than x, z is equal to or greater than 4 and equal to or less than about 13, .alpha. is a divalent cationic element having an ionic radius greater than divalent magnesium, and .beta. is a trivalent cationic element having an ionic radius greater than trivalent aluminum. The monocrystalline lattice has tetrahedral positions and octahedral positions, and most of the magnesium and .alpha. occupy tetrahedral positions. In one embodiment, the molar ratio of aluminum to the amount of magnesium, .alpha. and .beta. can be controlled during grow th of the monocrystalline lattice thereby forming a spinel substrate suitable f or heteroepitaxial growth of III-V materials. A method of the invention, includ es forming a monocrystalline lattice of spinel composition. A composition includes the spinel composition layer and a III-V layer at the surface of th e spinel layer. A method of forming a composite includes depositing the III-V layer onto the surface of the spinel composition using heteroepitaxial techniques. |
