SEMICONDUCTOR SUBSTRATE
A method for manufacturing a semiconductor substrate. The method provides a single-crystal diamond base layer. The method then forms a beryllium oxide (BeO) layer over the single-crystal diamond base layer. The method then forms a gallium nitride (GaN) layer over the BeO layer. In some embodiments, the method forms surfactants over the single-crystal diamond base layer and the BeO layer.
1 . A method for manufacturing a semiconductor substrate, comprising:
providing a single-crystal diamond base layer;
epitaxially forming a single-crystal beryllium oxide (BeO) layer over the single-crystal diamond base layer; and
epitaxially growing a single-crystal gallium nitride (GaN) layer over the BeO layer.
2 . The method of claim 1 , wherein the single-crystal diamond base layer has a grain size greater than 1 mm.
3 . The method of claim 1 , wherein the GaN layer contains a single GaN crystal.
4 . The method of claim 1 , comprising providing a surfactant over the BeO layer before epitaxially growing the single-crystal GaN layer.
5 . The method of claim 1 , comprising providing a surfactant over the single-crystal diamond base layer before epitaxially growing the BeO layer.
6 . The method of claim 5 , wherein the surfactant includes a surfactant lattice constant value between a BeO lattice constant value and a GaN lattice constant value.
7 . The method of claim 5 , wherein forming the surfactant includes patterning a surface of the BeO layer or the single-crystal diamond base layer.
8 . A semiconductor substrate, comprising:
a single-crystal diamond base layer;
a single-crystal beryllium oxide (BeO) layer formed over the single-crystal diamond base layer; and
a single-crystal gallium nitride (GaN) layer formed over the BeO layer.
9 . The semiconductor substrate of claim 8 , wherein the single-crystal diamond base layer is configured to include a grain size greater than 1 mm.
10 . The semiconductor substrate of claim 8 , wherein the GaN layer is a seed layer configured to receive an additional GaN layer.
11 . The semiconductor substrate of claim 8 , wherein the GaN layer contains a single GaN crystal.
12 . The semiconductor substrate of claim 8 , comprising: a surfactant located at an interface between the single-crystal diamond base layer and the BeO layer, or at an interface between the BeO layer and the GaN layer.
13 . The semiconductor substrate of claim 12 , wherein the surfactant has a surfactant lattice constant value between a BeO lattice constant value and a GaN lattice constant value.
14 . The semiconductor substrate of claim 12 , wherein the top surface of the BeO layer and/or the single-crystal diamond base layer is patterned.
15 . A method for manufacturing a semiconductor substrate, comprising:
providing a single-crystal diamond base layer;
epitaxially growing a beryllium oxide (BeO) layer over the single-crystal diamond base layer; and
patterning a growth surface of the BeO layer prior to epitaxially growing a gallium nitride (GaN) layer on the growth surface, the patterning configured to provide elongated lateral overgrowth of the GaN layer.
16 . The method of claim 15 , wherein the single-crystal diamond base layer has a grain size greater than 1 mm.
17 . The method of claim 15 , comprising epitaxially growing a single-crystal GaN layer over the BeO layer.
18 . The method of claim 15 , further comprising providing a surfactant over the BeO layer.
19 . The method of claim 18 , wherein the surfactant has a surfactant lattice constant value between a BeO lattice constant value and a GaN lattice constant value.
20 . The method of claim 18 , wherein the surfactant includes iridium or titanium.