Single Barrier-Liner Interconnect Structure for Copper Diffusion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing interconnect structures in semiconductor devices face challenges with copper diffusion, which can lead to performance degradation or device failure, as they rely on separate barrier and liner layers that occupy significant volume, increasing resistance and requiring complex processes.
Innovation Solution
A single layer serving as both a barrier and a liner is introduced, composed of a main component like cobalt or ruthenium and a doping component such as tantalum, deposited conformally to separate the bulk metal region from the dielectric layer, enhancing thermal stability and adhesion while reducing volume occupancy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate barrier layer and liner layer are deposited sequentially, then copper diffusion is prevented, but interconnect resistance increases and manufacturing complexity increases
Solution Approach 1:
The patent combines the barrier layer and liner layer into a single integrated layer that performs both functions simultaneously. This single layer is deposited conformally to provide both copper diffusion barrier properties and copper deposition promotion properties, eliminating the need for separate sequential deposition of two distinct layers.
Solution Approach 2:
The single barrier/liner layer is designed to perform multiple functions: it acts as a diffusion barrier to prevent copper from migrating into the dielectric, while simultaneously serving as a liner that promotes copper deposition. This multi-functional layer replaces the traditional two-layer system, reducing manufacturing steps and complexity.
2Reliability
If separate barrier layer and liner layer are deposited sequentially, then copper diffusion is prevented, but volume occupancy increases
Solution Approach 1:
The patent combines the barrier layer and liner layer into a single integrated layer that performs both functions simultaneously. This single layer is deposited conformally to provide both copper diffusion barrier properties and copper deposition promotion properties, eliminating the need for separate sequential deposition of two distinct layers.
3Device complexity
If single layer serves as both barrier and liner, then manufacturing process is simplified, but thermal stability and adhesion must be enhanced
Solution Approach 1:
The single barrier/liner layer is formed as a composite material containing both a liner component (such as cobalt or ruthenium) that promotes copper deposition, and a barrier component (such as tantalum, tungsten, or molybdenum) that prevents copper diffusion. This composite structure enables the layer to achieve both functionality while maintaining thermal stability and adhesion properties.
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 single barrier/liner layer effectively prevents copper diffusion, reduces interconnect resistance, and simplifies the manufacturing process by occupying less volume, thereby improving the semiconductor device's performance and yield.
Implementation Method 1
The barrier layer is made of metal nitride, and is used for preventing the metal material from diffusing into neighboring sensitive regions
Implementation Method 2
The liner layer is made of a single metal, and is used for permitting the metal material to be deposited thereon
Data Source
AI summary
A semiconductor device includes a substrate and an interconnect layer disposed on the substrate. The interconnect layer includes a dielectric layer and an interconnect extending through the dielectric layer. The interconnect includes a bulk metal region and a single barrier/liner layer, which serves as both a barrier layer and a liner layer and which is disposed to separate the bulk metal region from the dielectric layer.