Abstract: A mask alignment method for a substrate holding apparatus. A first engaging portion is formed in one of a substrate holder and a mask and has two protruding portions. A second engaging portion is formed in the other one of the substrate holder and the mask and has at least one protruding portion. First groove portions formed in the other one of the substrate holder and the mask engage with the protruding portions of the first engaging portion. A second groove portion formed in the other one of the substrate holder and the mask engages with the protruding portion of the second engaging portion.

Abstract: The present invention provides a mask alignment mechanism which reduces the occurrence of particles and which aligns a mask with high accuracy, and a vacuum processing apparatus including such a mask alignment mechanism. A mask alignment mechanism according to one embodiment of the present invention includes a substrate holder which is movable up and down when a substrate is transferred and on which four taper pins are formed, and a mask in which grooves are formed. The taper pins can be inserted into the grooves, respectively. The taper pins include a pair of long taper pins and a pair of short taper pins. The taper pins in each pair are disposed to face each other across the substrate. Tapered surfaces formed in the long taper pins and tapered surfaces formed in the short taper pins are located at different heights.