PROCESSING METHOD OF WORKPIECE

PROCESSING METHOD OF WORKPIECE A processing method for processing a workpiece includes a holding step of holding the front surface side of the workpiece on which an alignment mark is formed by a holding table having a holding surface that reflects a near-infrared ray and exposing the back surface side and an imaging step of emitting the near-infrared ray toward the back surface side of the workpiece held by the holding table and imaging the workpiece by an imaging unit that has sensitivity to the near-infrared ray and faces the back surface side of the workpiece to form a captured image. The processing method also includes an alignment mark detection step of detecting the alignment mark based on the captured image and a processing step of processing the workpiece held by the holding table by a processing unit based on the detected alignment mark. (Figure 1B)