d form of the manufacturing method of an active matrix substrate according to the present invention includes following processes: A first conductive film consisting of one conductive material is patterned to form a first conductive film pattern on an insulating substrate, and depositing in order an insulation layer, a semiconductor thin film, a semiconductor thin film for ohmic contact, and a second conductive film consisting of other conductive material to form laminated films on the insulating substrate and the first conductive film pattern. After that, a resist pattern having a second portion with a opening therein and a first portion thicker than the first portion is formed on the second conductive film and etching the 