Plasma etching method and plasma etching apparatus

Abstract

There are provided a plasma etching method and a plasma etching apparatus capable of independently controlling distributions of line widths and heights of lines in a surface of a wafer. The plasma etching method for performing a plasma etching on a substrate W by irradiating plasma containing charged particles and neutral particles to the substrate W includes controlling a distribution of reaction amounts between the substrate W and the neutral particles in a surface of the substrate W by adjusting a temperature distribution in the surface of the substrate W supported by a support 105, and controlling a distribution of irradiation amounts of the charged particles in the surface of the substrate W by adjusting a gap between the substrate W supported by the support 105 and an electrode 120 provided so as to face the support 105.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of Japanese Patent Application No. 2010-054828 filed on Mar. 11, 2010, the entire disclosures of which are incorporated herein by reference.FIELD OF THE INVENTION[0002]The present disclosure relates to a plasma etching method and a plasma etching apparatus for performing a plasma etching on a substrate.BACKGROUND OF THE INVENTION[0003]In manufacturing a semiconductor device, as an apparatus for processing a substrate such as a semiconductor wafer (hereinafter, referred to as “wafer”), there has been used a plasma etching apparatus which performs an etching process on the wafer by irradiating plasma to the wafer.[0004]By way of example, a wafer yet to be processed in the above-described plasma etching apparatus is formed of a silicon substrate. On the wafer, a silicon dioxide (SiO2) film, an etching target film formed of a polysilicon film, a mask film formed of a single layer or multiple layers, a bottom...

AI Technical Summary

Benefits of technology

[0020]In accordance with the present disclosure, it is possible to independently control distributions of widths and heights of lines in a surface of a wafer and it is also possible to perform an etching process with high uniformity in cross sectional shapes of lines when the lines are formed by etching a layered mask film including an inorganic film and an organic film or when multiple kinds of line groups having various gaps between adjacent lines are formed by etching a mask film.

Problems solved by technology

However, recently, in manufacturing a semiconductor device, a wafer becomes larger.

As the wafer becomes larger, it becomes difficult to obtain uniformity in line widths CD (critical dimension) and a height of lines formed on the surface of the wafer.

However, in case of using the above-described plasma etching apparatuses to perform a plasma etching process, there are some problems as follows.

However, as described above, when a pattern having both a sparse area and a dense area is required, it is impossible to perform an etching process with high uniformity in line widths of the lines formed on a wafer.

Thus, it is difficult to control the etching rate to a required level by controlling the supply amount or composition ratio of the processing gas.

Consequently, line widths and heights of the lines in the surface of the wafer cannot be uniformed and cross sections of the lines cannot be uniformed.

In case of using the processing gas having the radicals of the low reaction rate, even if the temperature of the wafer and the supply amount or composition ratio of the processing gas are adjusted within a typical variable range, an amount of reacted radicals is hardly changed and the line widths of the lines cannot be controlled.

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