Group III-nitrides on Si substrates using a nanostructured interlayer
A layered group III-nitride article includes a single crystal silicon substrate, and a highly textured group III-nitride layer, such as GaN, disposed on the silicon substrate. The highly textured group III-nitride layer is crack free and has a thickness of at least 10 μm. A method for forming highly textured group III-nitride layers includes the steps of providing a single crystal silicon comprising substrate, depositing a nanostructured In x Ga 1-x N (1≧x≧0) interlayer on the silicon substrate, and depositing a highly textured group III-nitride layer on the interlayer. The interlayer has a nano indentation hardness that is less than both the silicon substrate and the highly textured group III-nitride layer.
1. A layered group III-nitride article, comprising:
a single crystal silicon comprising substrate;
a nanostructured interlayer; said nanostructured interlayer comprising a nanostructured feature selected from the group consisting of a columnar film, a plurality of nanorods, a plurality of microrods, and a combination thereof;
and a highly textured crystal group III-nitride layer, said highly textured group III-nitride layer being crack free and having a thickness of at least 10 μm wherein said nanostructured interlayer is disposed between said silicon substrate and said highly textured group III-nitride layer.
2. The article of claim 1 , wherein said silicon substrate is (111) or (100) oriented.
3. The article of claim 2 , wherein said highly textured group III-nitride layer comprises GaN.
4. The article of claim 3 , wherein said interlayer comprises an InGaN alloy.
5. The article of claim 1 , wherein said nanostructured interlayer comprises nanorods, microrods, or a combination thereof.
6. The article of claim 1 , wherein said nanostructured interlayer comprises nanorods, said nanorods being well aligned.
7. The article of claim 1 , wherein said nanostructured interlayer comprises nanorods, said nanorods being randomly oriented.
8. The article of claim 1 , wherein said nanostructured interlayer comprises nanorods, said nanorods having an average rod diameter of 300 to 700 nm.
9. The article of claim 1 , wherein said nanostructured interlayer comprises nano rods, said nanorods comprising InN.
10. The article of claim 1 , wherein said nanostructured interlayer comprises In x Ga 1-x N, wherein 1>x>0.
11. The article of claim 1 , wherein said nanostructured interlayer has a thickness of 0.1 to 3.0 μm.
12. The article of claim 1 , wherein said silicon substrate is (111) oriented.