Hetero epitaxial structure and method therefor

A heterogeneous epitaxial structure having a plurality of devices comprising:

• a substrate of a first material;
• an intermediate layer overlying the substrate comprising:
• a first layer of a second material configured to be formed by vertical epitaxial overgrowth;
• a plurality of pillars formed in the first layer wherein each pillar of the plurality of pillars has a top surface;
• a layer of a third material formed between the plurality of pillars;
• and
• a second layer of the second material configured to be formed by epitaxial lateral overgrowth wherein the epitaxial lateral overgrowth extends from the sidewalls of the plurality of pillars, wherein the epitaxial lateral overgrowth merges between adjacent or opposing pillars of the plurality of pillars, and wherein a void or gap exists between a portion of the layer of the third material and a surface of the intermediate layer;
• and
• at least one device layer of a fourth material formed on the surface of the intermediate layer wherein the plurality of devices are formed on or in the at least one device layer.

A heterogeneous epitaxial structure having a plurality of devices comprising:

• a substrate comprising silicon carbide (SiC) or silicon;
• an intermediate layer comprising:
• a plurality of pillars formed in a first layer of the intermediate layer wherein the first layer comprises Aluminum Nitride (AlN) and wherein the first layer is configured to be grown by vertical epitaxy;
• a layer of carbon or tantalum carbide in areas between the plurality of pillars;
• and
• a second layer of AlN configured to be grown by epitaxial lateral overgrowth wherein the second layer extends from sidewalls of the plurality of pillars, wherein merged epitaxial lateral overgrowth (MELO) is configured to occur between adjacent or opposing pillars of the plurality of pillars;
• at least one device layer comprising gallium nitride (GaN) configured to be formed by vertical epitaxy overlying the intermediate layer wherein the substrate, the first and second layers of the intermediate layer, and the at least one device layer are configured to be formed single crystal, wherein the third material is configured to be heated by laser to fracture portions of the AlN in the intermediate layer to fracture the intermediate layer to exfoliate the intermediate layer from the substrate such that the substrate is not consumed by exfoliation and is configured for reuse, and wherein the plurality of devices comprises diodes or transistors.