Origin height position method of detection of chuck table

摘要

PPROBLEM TO BE SOLVED: To provide a method for detecting the origin height position of a chuck table capable of detecting the height position of an origin without forming any annular recess in a holding part of the chuck table. PSOLUTION: The method for detecting the origin height position of the chuck table includes a height position detecting step of detecting the height position of a base by bringing a measurement needle 151a of a first height detector 15a from the evacuation position to an upper surface of a base 62 of the chuck table 6, and bringing a measurement needle 151b of a second height detector 15b from the evacuation position to a holding surface of a holding part 61 of the chuck table to detect the height position of the holding part, a chuck table positioning step of positioning the measurement needle of the first height detector and the measurement needle of the second height detector to the respective evacuation positions and turning the chuck table by a predetermined angle to position the chuck table to the next detection position, and an origin height position calculating step of repeating the height position detecting step and the chuck table positioning step to obtain the mean value of a plurality of height positions of the base, and to obtain the mean value of the height position of the holding part. PCOPYRIGHT: (C)2010,JPO&INPIT