FinFET Gate Contact Single Liner Reduces Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing finFETs face high contact resistance due to the presence of high-resistance layers such as the work function metal and diffusion barrier layer, which affects the device's functionality.
Innovation Solution
A single liner layer is formed that acts as both a contact barrier and a work function metal, eliminating the need for separate high-resistance layers and reducing overall contact resistance by merging the functions of the contact barrier and work function metal into a single layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate work function metal layer and diffusion barrier layer are used in gate contact, then proper finFET functionality is achieved, but contact resistance becomes relatively high
Solution Approach 1:
The patent combines the work function metal layer and diffusion barrier layer into a single integrated layer. This merged layer simultaneously provides the work function necessary for inducing charge in the channel region and the diffusion barrier protection, thereby eliminating the compounding effect of separate high-resistance layers while maintaining proper finFET functionality.
Solution Approach 2:
The single integrated layer performs multiple functions: it serves as the work function metal for charge induction in the channel region and simultaneously acts as the diffusion barrier layer protecting the gate contact. This multi-functional design reduces the number of layers and eliminates the contact resistance issue caused by stacking separate high-resistance layers.
2Reliability
If multiple layers (work function metal and diffusion barrier) are stacked in gate contact, then proper functionality is ensured, but device complexity increases
Solution Approach 1:
The patent merges two separate layers (work function metal layer and diffusion barrier layer) into a single integrated layer in the gate contact structure. This reduces the number of manufacturing steps and material depositions required, thereby simplifying the device structure and manufacturing process while maintaining the necessary functional properties.
Solution Approach 2:
The single integrated layer is designed to perform both the work function role (inducing charge in the channel) and the diffusion barrier role (protecting the gate contact). This multi-functionality eliminates the need for separate layers, reducing structural complexity and manufacturing complexity simultaneously.
Data Source
AI summary
An embodiment includes a substrate, wherein a portion of the substrate extends upwards, forming a fin, a gate dielectric over a top surface and sidewalls of the fin, a liner overlaying the gate dielectric, and an uninterrupted metallic feature over the liner a portion of the liner overlaying the gate dielectric, wherein the liner extends from a top surface of the uninterrupted metallic feature and covers sidewalls of the metallic feature, and wherein the gate dielectric, liner, and uninterrupted metallic feature collectively form a gate, a gate contact barrier, and a gate contact.