Patent ID: 8070972
Filing Date: 2011-12-06
Classification: H01J,H01L

Abstract:
1. An etching method for subjecting an object to be processed to an etching process, the object including: a substrate; a film to be etched that is formed on the substrate; and a photoresist mask provided with an opening, the photoresist mask being formed on the film; to form a concave portion in the film; the etching method comprising the steps of: determining, in advance, a first correlation between a parameter value of an etching process parameter and an opening dimension of the concave portion, when the etching process is conducted with the use of the mask provided with the opening of a reference opening dimension; determining, in advance, a second correlation between a variation in opening dimension of the opening the mask and a variation in opening dimension of the concave portion in the film; measuring an actual opening dimension of the opening in the mask in the object that is to be subjected to the etching process; determining a target parameter value of the etching process parameter for achieving a target opening dimension of the concave portion, based on a difference between the actual opening dimension of the opening in the mask and the reference opening dimension of the opening in the mask, the target opening dimension of the concave portion to be formed, and the first and second correlations; and conducting an etching process to the object to be processed, so as to make the etching process parameter correspond to the target etching parameter value, wherein the etching process is conducted by using at least two types of etching gases, and the etching process parameter is a ratio of flow rates of the etching gases.