| 摘要 |
The present invention is to provide a lift off method capable of accurately separating an epitaxy substrate. The life off method is about moving an optical device layer on an optical device wafer to a transferring substrate by putting a buffer layer made of Ga composites including Ga on the surface of the epitaxy substrate. The lift off method includes a transferring substrate joining process which puts a joining metal layer on the surface of the optical device layer on the optical device wafer; a gas layer forming process which forms gas layers on the boundary surface between the epitaxy substrate and the buffer layer by radiating pulse laser rays with a wavelength, which are permeable through the expitaxy substrate and are absorbable into the buffer layer, from the rear side of the epitaxy substrate toward the buffer layer; a gas layer detecting process which detects the area of the outermost gas layer among the gas layers formed on the boundary surface between the epitaxy substrate and the buffer layer; an epitaxy substrate attaching process which places a suction pad on the area on which the outermost gas layer is placed on the epitaxy substrate to be attached to the epitaxy substrate; and an optical device moving process which moves the suction pad, which is attached to the epitaxy substrate, opposite to the epitaxy substrate and separates the epitaxy substrate to move the optical device layer to the transferring substrate. |
