Gas processing apparatus and gas processing method

#This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2018-151874, filed on Aug. 10, 2018, the entire contents of which are incorporated herein by reference.

#The present disclosure relates to a gas processing apparatus and a gas processing method.

#A gas processing, such as film formation by atomic layer deposition (ALD) or chemical vapor deposition (CVD), is often carried out on a semiconductor wafer (hereinafter, referred to as a “wafer”), which is a substrate. During the gas processing, a gas is supplied to the wafer, for example, in a shower shape. Patent Document 1 describes a film forming apparatus that performs chemical vapor deposition (CVD) by supplying a gas to a mounting table, on which a wafer is mounted. In the film forming apparatus, a susceptor for supporting the wafer and a shower head provided above the susceptor are installed. The shower head includes a first porous plate (face plate) facing the wafer and having a plurality of holes formed therein, and a second porous plate (blocker plate) installed above the first porous plate so as to vertically partition a gas diffusion space constituting the shower head.

#The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

#FIG. 1 is a longitudinal sectional side view of a film forming apparatus according to one embodiment of the present disclosure.

#FIG. 2 is a longitudinal sectional side view of a shower plate and an upper shower head constituting the film forming apparatus.

#Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, systems, and components have not been described in detail so as not to unnecessarily obscure aspects of the various embodiments.

#A film forming apparatus 1 according to one embodiment of a gas processing apparatus of the present disclosure will be described with reference to a longitudinal sectional side view of FIG. 1. The film forming apparatus 1 includes a flat circular process vessel 11. In the process vessel 11, a vacuum atmosphere is formed and a wafer W, which is a circular substrate having a diameter of, for example, 300 mm, is stored. The film forming apparatus 1 performs ALD by alternately and repeatedly supplying a titanium tetrachloride (TiCl4) gas as a raw material gas and an ammonia (NH3) gas as a reaction gas to the wafer W to form a titanium nitride (TiN) film. A nitrogen (N2) gas as an inert gas is supplied as a purge gas between a time period for supplying the TiCl4 gas as a first processing gas and a time period for supplying the NH3 gas as a second processing gas. By supplying the purge gas, the internal atmosphere of the process vessel 11 is changed from a TiCl4 gas atmosphere or an NH3 gas atmosphere to an N2 gas atmosphere. In addition, the N2 gas is continuously supplied into the process vessel 11 as a carrier gas for introducing the TiCl4 gas and the NH3 gas into the process vessel 11 during a film forming process by ALD.

#A wafer loading/unloading port 12 and a gate valve 13 for opening and closing the loading/unloading port 12 are installed on a sidewall of the process vessel 11. An exhaust duct 14, which forms a portion of the sidewall of the process vessel 11 and is formed by annularly curving a duct having a rectangular longitudinal section, is installed on an upper portion of the loading/unloading port 12. A slit-like opening 15 extending along a circumferential direction of the exhaust duct 14 is formed on an inner peripheral surface of the exhaust duct 14 to form an exhaust port of the process vessel 11.