Publication Date:
2015-12-09
Description:
The incorporation of In on the non-polar, piezoelectric-free (001) facet of cubic ( c -) GaN epitaxially grown over a Si(001) substrate by metal-organic vapor phase epitaxy is reported. Relying on a hexagonal ( h -) to c -phase transformation during epitaxy on an 800 nm-wide, Si(111)-faceted v-groove patterned into the substrate, the GaN epilayer at cross sectional view retains a triangular c -phase inside a chevron-shaped h -phase that results in a top surface bounded by a (001) facet parallel to Si(001) at the center and ( 1 1 ¯ 01 ) facets at both edges. A stack of five, ∼3 nm-thick, In x Ga 1−x N/GaN quantum wells (QWs) was deposited on the double-phased top surface. The c -phase region up to the QWs keeps extremely small misfit (∼0.002) to the fully relaxed h -GaN underneath it and is in tensile stress implying undefected by the h-c phase interface. The In incorporation on a strained non-polar (001) of c -GaN is comparable with that on totally relaxed semi-polar ( 1 1 ¯ 01 ) of h -GaN without noticeable adatom migration across the phase boundary, and sufficient to provide the room-temperature green emission at 496 nm from the c -In x Ga 1−x N/GaN QWs on Si(001) in photoluminescence.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
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