ROTATIONAL DRIVING DEVICE FOR SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To stably hold a rectangular substrate and to ensure the smooth rotation of this substrate at the time of the substrate is mounted at a spindle and is rotated. SOLUTION: The holding means of the substrate 1 disposed at the front end of the revolving shaft 21 of the spindle 20 consists of a ring part 27 which is concentric with the center of rotation of the revolving shaft 21 and plural pieces of connecting arms 28 spanned between this ring part 27 and the revolving shaft 21. Plural regulating pins 29 are erected at the ring part 27. When the substrate 1 is mounted at the spindle 20, one piece each of these regulating pins 29 engages with the two short side parts and two pieces each of the regulating pins 29 engage with the two long side parts. Plural pieces of supporting pins 30 which come into contact with the rear surface of the substrate 1 are erected at the proper points of the connecting arms 28 and the ring part 27.