| 摘要 |
PROBLEM TO BE SOLVED: To provide a lift-off method capable of surely exfoliating an epitaxy substrate without reducing the quality of an optical device.SOLUTION: A lift-off method is configured to transfer, to a transfer substrate, an optical device layer of an optical device wafer in which the optical device layer is laminated on a surface of an epitaxy substrate via a buffer layer. The lift-off method includes: a composite substrate forming step of forming a composite substrate by bonding the transfer substrate to a surface of the optical device layer in the optical device wafer via a bond; a buffer layer destruction step of destroying the buffer layer by irradiating the buffer layer, from the rear side of the epitaxy substrate of the composite substrate, with laser beams of a wavelength having transmissivity with respect to the epitaxy substrate and having absorptivity with respect to the buffer layer; and an optical device layer transfer step of transferring the optical device layer to the transfer substrate by exfoliating the epitaxy substrate of the composite substrate on which the buffer layer destruction step is implemented. In the buffer layer destruction step, the buffer layer is irradiated with the laser beams while mitigating spring-back that is generated in the epitaxy substrate and the transfer substrate by heating the composite substrate. |
