Ruthenium CVD with Reducing Gas for Oxidation-Free Interfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chemical vapor deposition methods face challenges in depositing ruthenium on certain underlying layers, such as copper layers, due to the use of oxidizing compounds that can damage substrate materials and lead to undesirable oxidation, resulting in less conductive interfaces.
Innovation Solution
The use of a ruthenium precursor of the formula R1R2Ru(0), where R1 is an aryl group-containing ligand and R2 is a diene group-containing ligand, in combination with a reducing gas like hydrogen, allows for selective and high-quality ruthenium deposition, minimizing oxidation damage and enhancing deposition rates on conductive substrates while avoiding non-conductive materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If oxidizing compounds are used for ruthenium deposition, then ruthenium can be successfully deposited on the substrate, but oxidation damage occurs to underlying nitride films and other substrate materials
Solution Approach 1:
The patent uses an inert atmosphere (nitrogen or argon) instead of oxidizing compounds during ruthenium deposition. The inert gas environment prevents oxidation of the underlying nitride films and other substrate materials while still allowing successful ruthenium film formation through thermal decomposition of the ruthenium precursor
Solution Approach 2:
The patent changes the chemical environment parameter from oxidizing to inert atmosphere. By maintaining a non-oxidizing environment and controlling temperature parameters, the process achieves ruthenium deposition without the harmful oxidation effects that occur with traditional oxidizing compound-based CVD processes
2Productivity
If traditional CVD methods are used for ruthenium deposition, then deposition can proceed on various substrates, but carbon residue remains in the deposited film
Solution Approach 1:
The patent optimizes deposition temperature parameters to enhance carbon removal. By conducting deposition at elevated temperatures (200-450°C) and controlling the thermal profile, the process promotes complete decomposition of the ruthenium precursor and volatilization of carbon-containing byproducts, resulting in high-quality films with minimal carbon residue
Solution Approach 2:
The patent converts the potentially harmful carbon residue into a beneficial outcome by using controlled thermal processing. The heat treatment that could otherwise cause unwanted reactions instead promotes carbon volatilization and film purification, transforming the carbon-containing precursor issue into a mechanism for producing clean, high-quality ruthenium films
3Reliability
If oxidizing conditions are used during deposition, then ruthenium film formation is achieved, but contact resistance increases due to oxidation at the interface
Solution Approach 1:
The patent maintains an inert atmosphere throughout the deposition process to prevent oxidation at the ruthenium-substrate interface. This ensures low contact resistance and high interface conductivity while still achieving complete and uniform ruthenium film formation through the inert-gas-mediated thermal decomposition process
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
This approach enables the formation of high-quality ruthenium films with minimal carbon residue and an oxygen-free interface, improving nucleation and reducing contact resistance, thereby providing a reliable barrier layer between conductive interconnects and low k dielectric materials in microelectronic articles.
Implementation Method 1
In one embodiment, the invention provides a method for depositing ruthenium on a substrate material using CVD. The CVD method includes steps of vaporizing a ruthenium precursor of the formula R1R2Ru(0)... and contacting a substrate with the vaporized ruthenium precursor and a reducing gas, wherein ruthenium is deposited on the substrate.
Implementation Method 2
contacting a substrate with the vaporized ruthenium precursor and a reducing gas, wherein ruthenium is deposited on the substrate. The use of a reducing gas like hydrogen... minimizing oxidation damage
Data Source
AI summary
Chemical vapor deposition (CVD) processes which use a ruthenium precursor of formula R1R2Ru(0), wherein R1 is an aryl group-containing ligand, and R2 is a diene group-containing ligand and a reducing gas a described. The CVD can include oxygen after an initial deposition period using the ruthenium precursor and reducing gas. The method can provide selective Ru deposition on conductive materials while minimizing deposition on non-conductive or less conductive materials. Further, the subsequent use of oxygen can significantly improve deposition rate while minimizing or eliminating oxidative damage of the substrate material. The method can be used to form Ru-containing layers on integrated circuits and other microelectronic devices.