INDIUM TIN OXIDE THIN FILM, ITS FORMATION, DISPLAY DEVICE AND THIN-FILM TRANSISTOR

摘要

PURPOSE:To provide an indium tin oxide thin film and a method for forming this thin film capable of forming a good tapered shape at an etching section for obtaining excellent step coverage. CONSTITUTION:The indium tin oxide thin film 2 is deposited by a DC sputtering method on a transparent insulating substrate 1. At this time, the indium tin oxide thin film 2 which has a high oxygen concn. at the film surface and has the oxygen concn. decreasing in the film thickness direction from the film surface is obtd. by introducing a gaseous mixture 3 composed of an inert gas and oxygen as a sputtering gas and increasing the ratio of the oxygen in a gaseous mixture 3 with an increase in the film thickness. Next, photoresist patterns 4 are formed by a method such as ordinary photolithography. The indium tin oxide thin film patterns 5 having the good tapered shape at the etched section are formed if the indium tin oxide thin film 2 is etched by an etching liquid such as aq. ferrous chloride soln.