Source/Drain Contact Formation With Remote Plasma Anti-Segregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As semiconductor devices continue to integrate more components into a given area through reduced minimum feature sizes, challenges arise in the fabrication process that need to be addressed.
Innovation Solution
A non-segregating process is employed to form source/drain contacts in semiconductor devices, utilizing techniques such as reactive ion etching, epitaxial growth, and selective deposition of materials like silicon germanium and high-k dielectrics to enhance the integration density and performance of finFET transistors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If minimum feature size is reduced to increase integration density, then more components can be integrated into a given area, but fabrication process challenges and manufacturing precision difficulties increase
Solution Approach 1:
The fabrication process is divided into multiple sequential steps including forming mandrels, depositing first spacers, forming second spacers, and creating source/drain regions. Each step builds upon the previous one, allowing precise control at each stage rather than attempting to create the final structure in a single step. This segmentation enables better manufacturing precision while achieving high integration density.
Solution Approach 2:
Mandrels are formed first as preliminary structures that guide the subsequent formation of spacers and source/drain regions. The first and second spacers are deposited and patterned before the actual source/drain regions are created. These preliminary actions establish precise geometric constraints that ensure manufacturing precision is maintained even as feature sizes are reduced for higher integration density.
2Ease of manufacture
If conventional segregating processes are used to form source/drain contacts, then fabrication is simpler, but material segregation and contact quality deteriorate
Solution Approach 1:
The process uses selective epitaxial growth under controlled parameters to form source/drain regions. By adjusting growth conditions such as temperature, pressure, and precursor flow rates, the material composition and crystal structure are precisely controlled. This prevents unwanted segregation while maintaining fabrication feasibility, thereby improving contact quality without excessive complexity.
Solution Approach 2:
The source/drain contacts are formed using composite material structures including silicon germanium (SiGe) alloys and high-k dielectric materials. These composite materials are deposited in layered sequences with specific compositions that prevent segregation. The use of SiGe source/drain regions with controlled germanium content, combined with high-k dielectric liners, ensures material stability and contact quality while allowing for a somewhat complex but systematic fabrication 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
The process enables efficient formation of source/drain regions with precise control over dimensions and materials, improving the integration density and performance of semiconductor devices, particularly in 5 nm and 3 nm process nodes.
Implementation Method 1
introducing the plasma to the treatment chamber
Implementation Method 2
generating a plasma outside of the treatment chamber; introducing the plasma to the treatment chamber
Data Source
AI summary
A semiconductor device and method of manufacture are provided which utilize a remote plasma process which reduces or eliminates segregation of material. By reducing segregation of the material, overlying conductive material can be deposited on a smoother interface. By depositing on smoother interfaces, overall losses of the deposited material may be avoided, which improves the overall yield.