Abstract: Disclosed herein is a wafer processing method for dividing a wafer into a plurality of individual devices along a plurality of crossing division lines. The wafer is composed of a substrate and a functional layer formed on the front side of the substrate. The division lines are formed on the front side of the functional layer. A laser beam having a transmission wavelength to the substrate is applied to the wafer from the back side thereof to detect the height of an interface between the functional layer and the substrate in an area corresponding to each division line. The depth of cut by a cutting blade for cutting the substrate is next set according to the height detected above.

Abstract: A plate-like object processing method for processing a plate-like object including a substrate and a laminate formed on a front surface of the substrate, includes a substrate exposing step of exposing the substrate by removing the laminate by irradiating a region in which the laminate of the plate-like object is desired to be removed with a laser beam set at an energy density that destroys the laminate but does not destroy the substrate.

Abstract: A wafer is divided into individual devices along division lines formed on the front side of the wafer. A protective tape having an adhesive layer is attached to the front side of a functional layer of the wafer with the adhesive layer of the protective tape in contact with the front side of the functional layer. The wafer with the protective tape is held on a holding surface of a chuck table with the protective tape in contact with the holding surface. A laser beam having an absorption wavelength to the substrate and the functional layer of the wafer is applied from the back side of the substrate along each division line to form a laser processed groove having a depth reaching the protective tape along each division line, thereby dividing the wafer into individual device chips corresponding to the individual devices.

Abstract: A wafer has a substrate, a functional layer and division lines. The wafer is held on a chuck table with a protective member attached to the front side of the functional layer in contact with the chuck table. The height of the back side of the wafer is detected in a Z direction along each division line while moving the chuck table in an X direction. An X coordinate is recorded for each division line, as well as a corresponding Z coordinate. A cutting blade is positioned on the back side of the wafer and moved in the Z direction according to the recorded X and Z coordinates while moving the chuck table in the X direction to thereby form a cut groove having a depth not reaching the functional layer, with a part of the substrate left between the bottom of the cut groove and the functional layer.

Abstract: A wafer has a substrate, a functional layer and division lines. The wafer is held on a chuck table with a protective member attached to the front side of the functional layer in contact with the chuck table. The height of the back side of the wafer is detected in a Z direction along each division line while moving the chuck table in an X direction. An X coordinate is recorded for each division line, as well as a corresponding Z coordinate. A cutting blade is positioned on the back side of the wafer and moved in the Z direction according to the recorded X and Z coordinates while moving the chuck table in the X direction to thereby form a cut groove having a depth not reaching the functional layer, with a part of the substrate left between the bottom of the cut groove and the functional layer.

Abstract: A plate-like object processing method for processing a plate-like object including a substrate and a laminate formed on a front surface of the substrate, includes a substrate exposing step of exposing the substrate by removing the laminate by irradiating a region in which the laminate of the plate-like object is desired to be removed with a laser beam set at an energy density that destroys the laminate but does not destroy the substrate.