Pattern forming method and manufacturing method of semiconductor device

摘要

A disclosed mask pattern forming method includes isotropically coating a surface of a resist pattern array having a predetermined line width with a silicon oxide film, embedding a gap in the resist pattern array coated by the silicon oxide film with a carbon film, removing the carbon film from the upper portion and etching back the carbon film while leaving the carbon film within the gap in any order, removing the remaining carbon film and etching back the upper portion of the resist pattern array to have a predetermined film thickness in any order, and forming a first mask pattern array which has a center portion having a predetermined width and film sidewall portions sandwiching the predetermined width, and arranged interposing a space width substantially the same as the predetermined line width with an asking process provided to the resist pattern array exposed from the removed silicon oxide film.

主权项

1. A mask pattern forming method comprising:
a first step of isotropically coating a surface of a resist pattern array, which is formed on an anti-reflective coating film and has a predetermined line width with a silicon oxide film until a gap in the resist pattern array becomes a predetermined size; a second step of coating the surface of the resist pattern array coated by the silicon oxide film with a carbon film to embed the gap in the resist pattern array coated by the silicon oxide film with the carbon film; a third step of etching back the carbon film to partly remove the carbon film from the surface of the resist pattern array coated by the silicon oxide film while leaving the carbon film within the gap in the resist pattern array coated by the silicon oxide film, wherein the etching back the carbon film is carried out in any order; a fourth step of etching back a portion of the silicon oxide film positioned above a top portion of the resist pattern array so that the resist pattern array is exposed from the silicon oxide film, and the silicon oxide film has a predetermined film thickness and the carbon film left within the gap in the third step is removed, wherein the etching back the portion of the silicon oxide film above the resist pattern array is carried out in any order; and a first mask pattern array forming step of forming the first mask pattern array of first mask patterns each of which is made of the silicon oxide film, which has a center portion having a predetermined width and sidewalls sandwiching the center portion in a width direction, and is alternately arranged with a space width substantially the same as the predetermined line width on the anti-reflective coating film by applying an ashing process to the resist pattern array exposed through the silicon oxide film to completely remove the resist pattern array so that the anti-reflective coating film is exposed from the silicon oxide film.