High Frequency Plasma TaN Deposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for depositing tantalum nitride (TaN) films suffer from plasma damage, leading to increased capacitance, dielectric constant, leakage currents, and poor adhesion, especially in fine structures, which affects the performance and reliability of copper barriers in semiconductor processes.
Innovation Solution
The use of high frequency plasma, specifically in the range of 40 MHz, with tantalum precursors like pentakis(dimethylamino)tantalum (PDMAT) and a controlled substrate temperature, to densify the TaN films and enhance barrier properties without causing damage, resulting in lower resistivity and improved uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If higher power plasma is used to deposit TaN films, then deposition rate is improved, but plasma damage increases causing higher capacitance, increased dielectric constant, and greater leakage currents
Solution Approach 1:
The patent changes the plasma frequency parameter from conventional low frequency (e.g., 13.56 MHz) to high frequency (e.g., 40 MHz or higher). This parameter change allows the plasma to have sufficient energy for deposition while reducing the harmful ion bombardment damage to the TaN film and underlying layers, thereby achieving both improved deposition rate and reduced plasma damage simultaneously
2Productivity
If higher power plasma is used, then film deposition is enhanced, but adhesion quality deteriorates due to damage to the TaN layer and underlying layers
Solution Approach 1:
By changing the plasma frequency to high frequency (40 MHz or higher), the patent achieves enhanced film deposition while maintaining adhesion quality. The high frequency plasma provides sufficient reactive species for deposition without causing excessive ion damage that would compromise the integrity and adhesion of the TaN barrier layer
3Ease of manufacture
If conventional plasma parameters are used, then processing is simpler, but film density and barrier properties are insufficient
Solution Approach 1:
The patent implements high frequency plasma (40 MHz or higher) with optimized power and pressure parameters to achieve superior film density and barrier properties. While this requires adjusting process parameters, it enables the deposition of high-quality TaN films with the necessary density for effective copper diffusion barriers in advanced semiconductor devices
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method achieves lower resistivity and higher density TaN films with improved barrier properties and interface quality, reducing plasma damage and enhancing the performance of copper barriers in semiconductor processes.
Implementation Method 1
The substrate is sequentially exposed to a metal precursor and a high frequency plasma
Implementation Method 2
high frequency plasma comprises one or more of argon, hydrogen, ammonia, helium and nitrogen
Implementation Method 3
methods for the deposition of tantalum nitride (TaN) using CVD or ALD techniques
Data Source
AI summary
Methods for depositing metal layers, and more specifically TaN layers, using CVD and ALD techniques are provided. In one or more embodiments, the method includes sequentially exposing a substrate to a metal precursor, or more specifically a tantalum precursor, followed by a high frequency plasma.