Method for manufacturing semiconductor device
View Patent ↗The number of masks and photolithography processes used in a manufacturing process of a semiconductor device are reduced. A first conductive film is formed over a substrate; a first insulating film is formed over the first conductive film; a semiconductor film is formed over the first insulating film; a semiconductor film including a channel region is formed by etching part of the semiconductor film; a second insulating film is formed over the semiconductor film; a mask is formed over the second insulating film; a first portion of the second insulating film that overlaps the semiconductor film and second portions of the first insulating film and the second insulating film that do not overlap the semiconductor film are removed with the use of the mask; the mask is removed; and a second conductive film electrically connected to the semiconductor film is formed over at least part of the second insulating film.
1. A method for manufacturing a semiconductor device, comprising the steps of:
forming a first electrode and a second electrode over a substrate;
forming a first insulating film over the first electrode and the second electrode;
forming a second insulating film over the first insulating film;
forming a first conductive film over the second insulating film;
forming a first mask including a first region and a second region over the first conductive film, wherein a thickness of the first mask in the second region is smaller than a thickness of the first mask in the first region;
removing first portions of the first insulating film, the second insulating film, and the first conductive film with the use of the first mask to form a first opening and a second opening;
removing the first mask in the second region to form a second mask after removing the first portions;
removing a second portion of the first conductive film with the use of the second mask;
removing the second mask after removing the second portion;
forming a third insulating film over the second insulating film; and
forming a pixel electrode over the third insulating film, the pixel electrode electrically connected to the first electrode through the first opening, and forming a second conductive film over the third insulating film, the second conductive film electrically connected to the second electrode through the second opening and to the first conductive film through a third opening opened in the third insulating film,
wherein the first electrode and the second electrode are formed by etching a same conductive film, and
wherein the third opening is spaced apart from the second opening.
2. The method for manufacturing a semiconductor device, according to claim 1 , further comprising the steps of:
forming a semiconductor film over the substrate before forming the electrode;
forming a fourth insulating film over the semiconductor film; and
forming a first opening in the fourth insulating film.
3. The method for manufacturing a semiconductor device, according to claim 2 ,
wherein the electrode is electrically connected to the semiconductor film through the first opening in the fourth insulating film.
4. The method for manufacturing a semiconductor device, according to claim 2 ,
wherein the semiconductor film includes an oxide semiconductor.
5. The method for manufacturing a semiconductor device, according to claim 1 ,
wherein the third insulating film is formed on at least part of a side surface of the second insulating film in the opening.
6. The method for manufacturing a semiconductor device, according to claim 1 ,
wherein the third insulating film is formed on a side surface of the second insulating film and on at least part of the electrode in the opening.