Formation of contact hole of semiconductor device

Abstract

Abstract PURPOSE:To contrive the improvement in reliability by enabling a contact resistance exceedingly by effecting the follow-up etching of an oxide film formed on a surface of a semiconductor substrate by a mixed gas of herium, carbon tetrafluoride, and oxygen after the etching using an etching gas composed of halogen as a base. CONSTITUTION:After an oxide film 12 is formed on a surface of the semiconductor substrate 11 on which a diffusion region 11 and etc. are formed, a resist 13 is spread over the oxide film 12. After a window 14 is formed by removing the part for forming a contact hole of the resist 13, a contact hole is formed by etching by RIE using CHF3 as an etching gas. At this time, on the surface of semiconductor substrate 10, a damage layer 15 in which C and etc. invades and a polymer layer 16 produced by C, F and etc. are produced. The produced damage layer 15 and etc. are subjected to follow-up etching by using a plasma etching device and a mixed gas of He(95%)+CF4(3%)+O2(2%) as an etching gas. A wiring is formed by vapor deposition of aluminum or the like and the diffusion region 11 and the wiring 17 are brought in ohmic contact through a contact hole 18.

Inventors

• 👤 Akira Nishiguchi
• 👤 晃 西口

Bibliographic Details