Patent ID: 7585708

Claim:
A method for manufacturing a thin-film transistor, the method comprising the steps of: providing an apparatus having a light source, a substrate movement means onto which a substrate including a semiconductor device constituent part rests, and a mask means; forming a light beam emitted from said light source into a desired light beam comprising a prescribed shape; directing the desired light beam in a desired light path comprising a prescribed direction; moving the substrate movement means to oppose the desired light beam; whereby an operation of aligning the desired light path in said mask means with a desired location on said semiconductor device constituent part is performed by referencing an alignment mark provided on said semiconductor device constituent part; wherein the alignment mark is made of one and the same constituent material as a constituent material of a light-blocking layer and formed at one and the same position as said light-blocking layer, the light blocking layer for blocking light from a thin-film-transistor element.