In recent years, it has been required to achieve high integration and high performance of elements in the semiconductor industry supporting IT technology that progresses rapidly. Therefore, in a semiconductor manufacturing process, further improvements in micro-fabrication technology has been required. In this semiconductor manufacturing process, an etching technique is an important micro-fabrication technology. In recent years, in this etching technique, a plasma etching technique capable of efficient and large-area micro-fabrication has been a main stream.
This plasma etching technique is a kind of dry etching technique. In this technique, a mask pattern is formed on a solid material serving as a processing target with a resist, and reactive gas is introduced into a vacuum in a state in which this solid material is supported in the vacuum, and a high-frequency electrical field is applied to the reactive gas. Accordingly, accelerated electrons collide with gas molecules and are brought into a plasma state, and radicals (free radicals) and ions, which are generated from this plasma, are made to react with the solid material and are removed as a reactive product. As a result, a fine pattern is formed on the solid material.
Meanwhile, there is a plasma CVD method as one of the thin film growth techniques that combine source gas through the action of the plasma and deposit the obtained compound on a substrate. This method is a film forming method that applies a high-frequency electrical field to gas containing raw material molecules to perform plasma discharge, decomposes the raw material molecules with the electrons accelerated through this plasma discharge, and deposits the obtained compound. A reaction, which has not occurred only with thermal excitation at low temperature, is also allowed in the plasma because the gas molecules in a system collide with each other and are activated and turned into radicals in the plasma.
In semiconductor manufacturing apparatuses using plasma, such a plasma etching apparatus and a plasma CVD apparatus, an electrostatic chuck device has conventionally been used from the former as a device that simply attaches and fixes a wafer to a sample platform and maintains this wafer at a desired temperature.
As such an electrostatic chuck device, for example, the following electrostatic chuck device is proposed and is presented for practical use (PTL 1). In this electrostatic chuck device, an electrostatic chuck part where an upper surface of a ceramic substrate is used as a placement surface for placing a plate-shaped sample, such as a wafer, and which a plate-shaped electrode for electrostatic attraction is buried in, and a cooling base part in which a refrigerant flow path for circulating cooling water is formed, are integrally adhered to each other with an adhesive layer, and cooling gas holes are formed so as to pass through the electrostatic chuck part and the cooling base part.