Abstract: A wafer chuck holds a wafer on a surface thereof such that an image of the wafer can be formed from light reflected by the surface of the wafer chuck. The surface of the wafer chuck is a planar surface that has a reflectivity equal to or greater than 40%, and/or a whiteness index value equal to or greater than 90. The wafer chuck can include a ceramic containing aluminum oxide having a purity equal to or greater than 95%. The planar surface of the wafer chuck is such that light illuminating the surface of the wafer chuck is reflected by the surface of the wafer chuck through the wafer. The wafer chuck can be used with an apparatus for cutting the wafer, and the light reflected by the surface can be used to form an image of the wafer used identifying cutting lines on the wafer.

Abstract: Methods of cutting a light-emitting device chip wafer by using a laser scribing process. The method includes: preparing a wafer that has a plurality of semiconductor chips on an upper surface of the wafer; attaching a first tape covering the semiconductor chips to the upper surface of the wafer; forming scribing lines to define each of the semiconductor chips on the wafer by irradiating a laser beam onto a lower surface of the wafer; attaching a second tape to the lower surface of the wafer; and breaking the wafer into a plurality of chips by applying a physical force to the wafer along the scribing lines.

Abstract: A wafer chuck holds a wafer on a surface thereof such that an image of the wafer can be formed from light reflected by the surface of the wafer chuck. The surface of the wafer chuck is a planar surface that has a reflectivity equal to or greater than 40%, and/or a whiteness index value equal to or greater than 90. The wafer chuck can include a ceramic containing aluminum oxide having a purity equal to or greater than 95%. The planar surface of the wafer chuck is such that light illuminating the surface of the wafer chuck is reflected by the surface of the wafer chuck through the wafer. The wafer chuck can be used with an apparatus for cutting the wafer, and the light reflected by the surface can be used to form an image of the wafer used identifying cutting lines on the wafer.

Abstract: Provided is an apparatus for laser scribing. The laser scribing apparatus may include: a first laser emitter to emit a laser for a thickness measurement while moving towards a first axial direction of a substrate where a plurality of light emitting devices is formed; a laser receiver to receive a reflected laser when the laser emitted from the first laser emitter is reflected from the substrate; a thickness measurement unit to measure a thickness of the substrate based on a strength of the leaser received by the laser receiver; and a second laser emitter to generate a scribing line on the substrate by emitting a laser towards a first axial direction and a second axial direction of the substrate while adjusting a laser emission location based on the measured thickness.