| 摘要 |
PURPOSE:To mount a mask in a normal state, by mounting a mask on an electrically conducting reference surface, pressing the head of a pin against a spring, and electrically detecting the fact that the pin comes in contact with the reference surface. CONSTITUTION:The rod part of a nail-like electrically conducting pin 11a is movably received by a positioning pin 10a through an insulator so that when the end of the head of the pin 11a abuts on an end surface of a photomask 1, the bottom of the head can be in electrical contact with the pin 10a. A spring leaf 12 has one end thereof secured to an electrically conducting mask-mounting part 4 through an insulator 13a and the other end abutting on the end of the rod part of the pin 11a. When the head of the pin 11a does not abut on the end surface of the mask 1, the contact between the pins 11a and 10a is canceled by the resilience of the spring leaf 12a. Pins 10b, 10c are similarly provided with pins 11b, 11c and springs 12b, 12c, respectively. When the heads of the pins 11 come in contact with all the pins 10, respectively, an LED is turned ON. This constitution makes it possible to mount the photomask 1 in a normal state, without any rotation and alignment errors. |
