MANUFACTURING METHOD OF THIN FILM TRANSISTOR AND MANUFACTURING METHOD OF DISPLAY DEVICE

摘要

A manufacturing method of a thin film transistor and a display device using a small number of masks is provided. A first conductive film, an insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film are stacked. Then, a resist mask having a recessed portion is formed thereover using a multi-tone mask. First etching is performed to form a thin-film stack body, and second etching in which the thin-film stack body is side-etched is performed to form a gate electrode layer. The resist is made to recede, and then, a source electrode, a drain electrode, and the like are formed; accordingly, a thin film transistor is manufactured.