| 摘要 |
PROBLEM TO BE SOLVED: To smoothly peel an epitaxy substrate from an optical device layer even in a case where an optical device wafer of large diameter is lift off.SOLUTION: A lift-off method for transferring an optical device layer 12 for an optical device wafer to a transfer substrate 20, comprises: a transfer substrate bonding step in which a transfer substrate is joined to a surface of the optical device layer via a bonding layer; a peeling layer formation step in which a laser beam that is transmissive through an epitaxy substrate and absorbable by a buffer layer 13 is emitted from the back 11b side of the epitaxy substrate 11 of the optical device wafer with the transfer substrate joined thereto, thereby forming a peeling layer 19 on a boundary face between the epitaxy substrate and the buffer layer; and an optical device layer transfer step in which while an ultrasonic horn 40 having a shape surrounding the outer peripheral edge 11c of the epitaxy substrate is kept in contact with the back 11d of the outer peripheral edge 11c, the epitaxy substrate is vibrated to be peeled off from the transfer substrate, and the optical device layer is transferred to the transfer substrate.SELECTED DRAWING: Figure 8 |
