FinFET Channel Isolation Structure to Suppress Fermi-Level Pinning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor manufacturing processes face challenges in achieving high integration density and efficient electrostatic control due to direct contact between source/drain regions and channel layers, leading to fermi-level pinning and reduced mobility.
Innovation Solution
The process involves forming insulating layers between the source/drain regions and the channel layer, which separates them, using techniques like oxidation and deposition of high-k dielectric materials, and patterning to create a finFET structure with specific layer configurations to enhance channel width and reduce contact resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If source/drain regions are formed in direct contact with channel layer, then manufacturing process is simple, but fermi-level pinning occurs and mobility decreases
Solution Approach 1:
An insulating layer is introduced as an intermediary between the source/drain regions and the channel layer. This insulating layer prevents direct contact while maintaining electrical functionality, thereby suppressing fermi-level pinning and improving carrier mobility without significantly complicating the manufacturing process.
2Reliability
If insulating layer is introduced between source/drain regions and channel layer, then fermi-level pinning is suppressed and mobility increases, but device structure becomes more complex
Solution Approach 1:
The device structure is segmented into distinct functional regions with the insulating layer creating a clear separation between the source/drain regions and the channel layer. This segmentation allows each region to be optimized independently while maintaining overall device performance and controlling complexity through modular design.
Solution Approach 2:
The insulating layer is applied locally only where needed at the interface between source/drain regions and channel layer, rather than throughout the entire device. This localized approach improves mobility where required while minimizing the overall structural complexity and material usage.
3Reliability
If finFET structure with increased channel width is created, then electrostatic control is improved, but manufacturing precision requirements increase
Solution Approach 1:
The channel is extended into the vertical dimension by forming fins that protrude from the substrate. This three-dimensional finFET structure increases the effective channel width and improves electrostatic control without requiring proportional increases in lateral dimensions, thereby managing manufacturing precision requirements more effectively.
Solution Approach 2:
The finFET structure employs nested layering where the insulating layer is positioned within the vertical stack between the source/drain regions and the channel layer. This nested configuration allows multiple functional layers to be integrated in a compact vertical arrangement, improving electrostatic control while managing the complexity of layer alignment.
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 effectively suppresses fermi-level pinning, improves electrostatic control, and increases intrinsic mobility, resulting in enhanced semiconductor device performance and reliability.
Implementation Method 1
forming insulating layers between the source/drain regions and the channel layer
Implementation Method 2
deposition of high-k dielectric materials
Data Source
AI summary
A semiconductor device includes a substrate, a channel layer, a gate structure, source/drain regions, and an insulating layer. The channel layer is disposed over the substrate. The gate structure is disposed over the channel layer. The source/drain regions are disposed over the substrate and disposed at two opposite sides of the channel layer. The insulating layer is disposed between the channel layer and the source/drain regions.