Separation method of wafer
AssigneeDisco Corporation
InventorsAsahi NOMOTO, Kazuya HIRATA
Life of this patent
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Abstract
A wafer having a first surface, an opposite second surface, and an outer circumferential surface that includes a curved part curved outward in a protruding manner is separated into two wafers. Part of the wafer is removed along the curved part, and a separation origin is formed inside the wafer by positioning the focal point of a laser beam with a wavelength having transmissibility with respect to the wafer inside the wafer and executing irradiation with the laser beam while the focal point and the wafer are relatively moved in such a manner that the focal point is kept inside the wafer. The wafer is separated into two wafers by an external force.
Claims16
A separation method of a wafer by which the wafer having a first surface, a second surface on a side opposite to the first surface, and an outer circumferential surface that is located between the first surface and the second surface and that includes a curved part curved outward in a protruding manner is separated into two wafers on a side of the first surface and on a side of the second surface, the separation method comprising:
- a processing step of processing the wafer to remove part of the wafer along the curved part;
- a separation origin forming step of, after the processing step, forming a separation origin inside the wafer by positioning a focal point of a laser beam with a wavelength having transmissibility with respect to the wafer inside the wafer and executing irradiation with the laser beam while the focal point and the wafer are relatively moved in such a manner that the focal point is kept inside the wafer;
- and
- a separation step of separating the wafer into a wafer having the first surface and a wafer having the second surface from the separation origin by giving an external force after the separation origin forming step.
Dependencies are inferred from the claim text.