Methods for stable process in a reactive sputtering process using zinc or doped zinc target

Abstract

Embodiments disclosed herein generally relate to a method for seasoning a sputtering target in-situ with a substrate to be processed. New semiconductor compounds containing oxygen, nitrogen, and an element such as zinc, cadmium, tin, indium, and gallium are beginning to replace silicon as the material for active channels in TFTs. The new semiconductor compounds may be deposited by a reactive sputtering process. During the sputtering process, reactive gas reacts with the metal from the sputtering target and deposits on the substrate. Some of the reactive gas may react at the surface and lead to a buildup of a compound at the target surface. Because oxygen and nitrogen are quite reactive, an oxide or nitride compound may develop at the target surface. The oxide or nitride may be removed by seasoning the sputtering target. The seasoning may occur while the substrate is within the processing chamber.