Plasma Annealing Liner Layer Density and Impurity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As semiconductor device dimensions decrease, existing deposition techniques for liner layers, such as ALD and CVD, result in increased contamination and less dense films due to carbon impurities, leading to variations in work function and diffusion barrier effectiveness.
Innovation Solution
A plasma-based annealing process in a nitrogen or ammonia ambient at controlled temperatures and power levels is applied to the liner layer post-deposition, improving film density and reducing organic impurities, thereby achieving a more consistent stoichiometry and uniform work function.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional deposition techniques (ALD, CVD) are used to deposit liner layer, then the liner layer can be formed, but the film density is low and contamination increases due to carbon impurities
Solution Approach 1:
The patent applies plasma-based annealing to change the physical and chemical parameters of the deposited liner layer. By controlling plasma power (50-500 Watts), temperature (room temperature to 500°C), and ambient atmosphere (nitrogen, ammonia, or vacuum), the process transforms the liner layer from a contaminated, low-density state to a clean, high-density state with improved stoichiometry and reduced carbon impurities
Solution Approach 2:
The plasma environment acts as a strong oxidizing condition that removes carbon impurities from the liner layer. The plasma-generated reactive species oxidize and remove organic contaminants, thereby reducing carbon impurity contamination and improving film quality without requiring additional cleaning steps
2Length of moving object
If deposition techniques are used for smaller trenches with larger aspect ratios, then the liner layer can be deposited in scaled devices, but contamination is exacerbated and film quality deteriorates
Solution Approach 1:
The plasma-based annealing process extracts harmful carbon impurities from the liner layer through oxidation and volatilization. This removal process specifically targets contamination that becomes more severe in scaled devices, thereby improving film quality in smaller trenches with larger aspect ratios where conventional deposition struggles
3Length of stationary object
If thinner liner layer films are deposited, then spatial restrictions for miniaturization are satisfied, but contamination increases and diffusion barrier effectiveness decreases
Solution Approach 1:
By applying plasma-based annealing, the patent changes the density and compositional parameters of thin liner layers. This transformation enables thin films (5-20 nm) to achieve high density and low contamination levels, thereby maintaining effective diffusion barrier properties despite reduced thickness required for miniaturization
4Ease of manufacture
If conventional deposition is used, then the liner layer can be formed, but work function consistency varies due to contamination
Solution Approach 1:
The plasma-based annealing process continuously improves the liner layer quality by maintaining plasma treatment throughout the processing window. This continuous action ensures uniform removal of carbon impurities and consistent densification across the entire liner layer, resulting in uniform work function values essential for reliable device operation
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 process results in a denser and more stable liner layer with reduced contamination, enhancing the diffusion barrier properties and work function consistency, critical for advanced metallization applications in FEOL, MOL, and BEOL.
Implementation Method 1
annealing is performed in at least one of a nitrogen (N2) and ammonia (NH3) ambient, at a temperature of about 60° C. to about 500° C., and at a power of about 200 Watts to about 4500 Watts
Implementation Method 2
annealing is performed in at least one of a nitrogen (N2) and ammonia (NH3) ambient
Implementation Method 3
annealing the liner layer, wherein the annealing is performed in at least one of a nitrogen (N2) and ammonia (NH3) ambient... achieving a more consistent stoichiometry
Data Source
AI summary
A method for manufacturing a semiconductor device includes conformally depositing a liner layer on a top surface of a dielectric layer, and on sidewall and bottom surfaces of an opening in the dielectric layer, annealing the liner layer, wherein the annealing is performed in at least one of a nitrogen (N2) and ammonia (NH3) ambient, at a temperature of about 60° C. to about 500° C., and at a power of about 200. Watts to about 4500. Watts, and forming a conductive layer on the liner layer on the top surface of the dielectric layer, and on the liner layer in a remaining portion of the opening.