Formation of silicon nitride film by using atomic layer deposition method

Abstract

Disclosed is a method of forming a silicon nitride film which can form a silicon nitride film having a high film stress at a low process temperature. The method includes the steps of (a) supplying dichlorosilane into a reaction chamber containing a process object, thereby allowing chemical species originated from dichlorosilane as a precursor to be adsorbed on the process object; (b) hydrogenating chlorine contained in the chemical species, thereby removing the chlorine from the chemical species; and (c) supplying ammonia radicals into the reaction chamber, thereby nitriding the chemical species, from which the chlorine has been removed, by the ammonia radicals to, deposit resultant silicon nitride on the process object, wherein the steps (a), (b) and (c) are performed repeatedly for plural times in that order, thereby a silicon nitride film of a desired thickness is formed on a semiconductor wafer.

Description

technical field

[0001] The present invention relates to a technique for forming a silicon nitride film using atomic layer deposition (ALD: Atomic Layer Deposition). Background technique

[0002] The manufacturing process of a semiconductor device includes a process of forming a silicon nitride film on an object to be processed, for example, a semiconductor wafer, using an ALD method.

[0003] The ALD method is a kind of gas composed of two (or more than two) raw materials used for film formation under certain film formation conditions (temperature, time, etc.), which are alternately supplied to the substrate one by one, with one atomic layer Unit adsorption is a method of film formation using surface reactions. For example, along the surface of the object to be processed, the first raw material gas and the second raw material gas are alternately flowed, so that the raw material gas molecules in the first raw material gas are adsorbed on the surface of the processed object, ...

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