A pixel portion 100 of a liquid crystal display device comprises a thin film transistor T comprising a channel region 18, and source/drain regions 22, a source (data) line 26 for supplying current to the thin film transistor T, a color filter 23, and a pixel electrode 24. In forming the pixel portion 100, a gate electrode 13, a gate insulating film 16 and the channel region 18 are first formed on a glass substrate 10. On the glass substrate 10 after the formation of the channel region 18 is formed, a wall made of a polyimide film 20 surrounding the peripheries of the regions for forming the source/drain regions 22, the color filter 23, the pixel electrode 24 and the source line 26. Liquid materials are applied to the regions surrounded with a wall made of the polyimide film 20, and a heat treatment is carried out to form films, thereby forming elements such as the color filter 23 or the pixel electrode 24.