Methods of manufacturing engineered substrate structures for power and RF applications
A method of manufacturing a substrate includes forming a support structure by providing a polycrystalline ceramic core, encapsulating the polycrystalline ceramic core in a first adhesion shell, encapsulating the first adhesion shell in a conductive shell, encapsulating the conductive shell in a second adhesion shell, and encapsulating the second adhesion shell in a barrier shell. The method also includes joining a bonding layer to the support structure, joining a substantially single crystalline silicon layer to the bonding layer, forming an epitaxial silicon layer by epitaxial growth on the substantially single crystalline silicon layer, and forming one or more epitaxial layers by epitaxial growth on the epitaxial silicon layer.
1. A method of manufacturing a substrate, the method comprising:
forming a support structure by:
providing a polycrystalline ceramic core;
encapsulating the polycrystalline ceramic core in a first adhesion shell;
encapsulating the first adhesion shell in a conductive shell;
encapsulating the conductive shell in a second adhesion shell; and
encapsulating the second adhesion shell in a barrier shell;
joining a bonding layer to the support structure;
joining a substantially single crystalline silicon layer to the bonding layer;
forming an epitaxial silicon layer by epitaxial growth on the substantially single crystalline silicon layer; and
forming one or more epitaxial III-V layers by epitaxial growth on the epitaxial silicon layer.
2. The method of claim 1 further comprising forming a plurality of vias passing from the one or more epitaxial III-V layers to the epitaxial silicon layer.
3. The method of claim 1 wherein the polycrystalline ceramic core comprises aluminum nitride.
4. The method of claim 1 wherein the one or more epitaxial III-V layers comprise an epitaxial gallium nitride layer.
5. The method of claim 4 wherein the one or more epitaxial III-V layers further comprise an epitaxial aluminum nitride layer, or an epitaxial aluminum gallium nitride layer, or a combination thereof.
6. The method of claim 1 wherein:
the first adhesion shell comprises a first tetraethyl orthosilicate (TEOS) shell;
the conductive shell comprises a polysilicon shell;
the second adhesion shell comprises a second TEOS shell;
the barrier shell comprises a silicon nitride shell; and
the bonding layer comprises silicon oxide.
7. The method of claim 6 wherein:
the first TEOS shell comprises a single layer of TEOS;
the polysilicon shell comprises a single layer of polysilicon;
the second TEOS shell comprises a single layer of TEOS; and
the silicon nitride shell comprises a single layer of silicon nitride.
8. The method of claim 1 wherein a thickness of the one or more epitaxial III-V layers is about 5 μm or greater.
9. The method of claim 1 wherein joining the substantially single crystalline silicon layer is performed by exfoliation.
10. The method of claim 9 wherein the substantially single crystalline silicon layer has a thickness of about 0.5 μm.