Etching method

Abstract

Abstract PURPOSE: To form a smooth, linear taper on the section of a work, by forming the work in laminated layers after plasma treatment of one or more layer of the work composed of plural layers with activated gas, then by etching the work successiely. CONSTITUTION: A semiconductor substrate 11 is coated with a polycrystalline poly- Si layer 12 by CVD process. The surface of the layer 12 is exposed to a gas plasma atmosphere, e.g., an activated gas such as CCl 4 , freon etc. Then the layer 12 is coated with a silicon nitride layer 13 by CVD process to form a laminated work composed of layers 12, 13. Successively, a resist pattern 14 is formed on the work, and the layer 13 is etched with the pattern 14 used as an etching mask. Hereafter, the layer 12 is etched with an etching soln. contg. acetic acid as a principal component, and fluoric acid, phosphoric acid using the layer 13 as a mask, thereby the layer 12 obtains an etched section having linear inclination of about 45°. The pattern 14, and the layer 13 are removed if necessary. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Hiroshi Ono

Bibliographic Details