The present application discloses a photomask, a semiconductor device manufacturing method, a semiconductor device and a memory chip. The photomask includes a light pattern area and a light blocking area, wherein the light pattern area comprises at least one source line pattern unit and at least one a drain electrode contact hole pattern unit. In the process of using the photomask for photolithography, light can pass through the source line pattern unit and the drain electrode contact hole pattern unit to irradiate photoresist, so that light sensitization of the photoresist is achieved, an etching solution is used for removal of the photoreceptive photoresist to form source line and drain electrode contact terminal patterns, the number of times of the photolithography is reduced, the technological process of semiconductor device manufacturing is simplified, and the semiconductor device manufacturing cost is reduced.