SMOOTH SURFACE INSPECTION DEVICE

PROBLEM TO BE SOLVED: To provide a smooth surface inspection device capable of detecting defects on a semiconductor- and LED-wafer substrate surface, and an optical surface without using a floating head method and capable of detecting defects near a rotation center.SOLUTION: A built-in type micro heater 3 having a tip portion protruded by heat deformation, and a heat detection element 1 for detecting imperceptible heat are provided in a same probe to be defined as a contact sensor probe 4. The heat detection element 1 is disposed at a tip of the contact sensor probe 4. Relative motion is applied between the contact sensor probe 4 and a measurement object surface 10, with a minute gap retained between the tip of the contact sensor probe 4 and the measurement object surface 10, and imperceptible friction heat generated by contact between the heat detection element 1 and a minute protrusion 12 on the measurement object surface 10 is detected so as to detect the minute protrusion 12. The built-in micro heater 3 and the heat detection element 1 are coaxially disposed on the contact sensor probe 4.