Method of manufacturing GaN-based semiconductor device
A method of manufacturing a GaN-based semiconductor device includes the steps of: preparing a composite substrate including: a support substrate having a thermal expansion coefficient at a ratio of not less than 0.8 and not more than 1.2 relative to a thermal expansion coefficient of GaN; and a GaN layer bonded to the support substrate, using an ion implantation separation method; growing at least one GaN-based semiconductor layer on the GaN layer of the composite substrate; and removing the support substrate of the composite substrate by dissolving the support substrate. Thus, the method of manufacturing a GaN-based semiconductor device is provided by which GaN-based semiconductor devices having excellent characteristics can be manufactured at a high yield ratio.
1. A method of manufacturing a GaN-based semiconductor device comprising the steps of:
preparing a composite substrate including: a support substrate having a thermal expansion coefficient at a ratio of not less than 0.8 and not more than 1.2 relative to a thermal expansion coefficient of GaN; and a GaN layer bonded to said support substrate, using an ion implantation separation method;
growing at least one GaN-based semiconductor layer on said GaN layer of said composite substrate; and
removing said support substrate of said composite substrate by dissolving said support substrate.
2. The method of manufacturing a GaN-based semiconductor device according to claim 1 , further comprising the steps of:
bonding a transfer support substrate to said GaN-based semiconductor layer, after said step of growing said GaN-based semiconductor layer and before said step of removing said support substrate by dissolving said support substrate; and
fabricating said transfer support substrate and said GaN-based semiconductor layer into a device and a chip after said step of removing said support substrate by dissolving said support substrate.
3. The method of manufacturing a GaN-based semiconductor device according to claim 1 , further comprising the steps of: fabricating said GaN-based semiconductor layer grown on said composite substrate into a device and a chip; and mounting said GaN-based semiconductor layer fabricated into a device and a chip on a mount substrate, after said step of growing said GaN-based semiconductor layer and before said step of removing said support substrate by dissolving said support substrate.
4. The method of manufacturing a GaN-based semiconductor device according to claim 2 , wherein said support substrate includes at least one selected from the group consisting of molybdenum and a composite oxide of aluminum oxide and silicon oxide.
5. The method of manufacturing a GaN-based semiconductor device according to claim 1 , wherein said support substrate includes at least one selected from the group consisting of molybdenum and a composite oxide of aluminum oxide and silicon oxide.
6. The method of manufacturing a GaN-based semiconductor device according to claim 3 , wherein said support substrate includes at least one selected from the group consisting of molybdenum and a composite oxide of aluminum oxide and silicon oxide.