Silane and borane treatments for titanium carbide films

Abstract

Methods of treating metal-containing thin films, such as films comprising titanium carbide, with a silane/borane agent are provided. In some embodiments a film comprising titanium carbide is deposited on a substrate by an atomic layer deposition (ALD) process. The process may include a plurality of deposition cycles involving alternating and sequential pulses of a first source chemical that comprises titanium and at least one halide ligand, a second source chemical comprising metal and carbon, wherein the metal and the carbon from the second source chemical are incorporated into the thin film, and a third source chemical, wherein the third source chemical is a silane or borane that at least partially reduces oxidized portions of the titanium carbide layer formed by the first and second source chemicals. In some embodiments treatment forms a capping layer on the metal carbide film.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates generally to processes for producing metal carbide thin films on a substrate by atomic layer deposition. In some embodiments, titanium carbide films produced by the atomic layer deposition (ALD) processes disclosed herein can be used in metal gate and metal electrode applications in metal oxide semiconductor field effect transistors (MOSFETs), such as n-channel MOSFETs (NMOS).[0003]2. Description of the Related Art[0004]Atomic layer deposition (ALD) is a generally self-limiting process, whereby alternated pulses of reaction precursors saturate a substrate surface and leave no more than about one monolayer of material per pulse. The deposition conditions and precursors are selected to provide self-saturating reactions, such that an adsorbed layer in one pulse leaves a surface termination that is non-reactive with the gas phase reactants of the same pulse. A subsequent pulse of different reac...

AI Technical Summary

Benefits of technology

[0008]According to some embodiments of the invention, an organosilane, organoborane, silane, or borane (generally referred to herein as a “silane/borane agent”) is utilized in atomic layer deposition (ALD) processes for depositing a boron- or silicon-containing film comprising metal carbide from a halide-containing precursor or in treating a deposited film that comprises metal carbide. The silane/borane agent may be pulsed during or after a deposition cycle, or it may be applied to a thin

Problems solved by technology

Despite the lower impurity levels in ALD films, the impurity content in ALD films can still be a problem.

In some cases, the semiconductor process flow necessarily limits the maximum deposition temperature such that that some

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