Titanium Silicide and Nitride CVD Using Hydrogen Flow Selectivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in semiconductor manufacturing is the formation of titanium silicide and titanium nitride layers with high conformality and uniformity in high aspect-ratio contact regions, leading to issues such as contamination and increased fabrication time due to the use of separate deposition chambers, and the need for improved control over layer thicknesses.
Innovation Solution
A CVD and in-situ treatment process is employed to form titanium silicide and titanium nitride layers, allowing for improved conformality, uniformity, and controlled thicknesses, which can be applied to various semiconductor devices including finFETs and planar structures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate deposition chambers are used to form titanium silicide and titanium nitride layers, then contamination is reduced, but fabrication time increases and process complexity increases
Solution Approach 1:
The patent combines the deposition of titanium silicide and titanium nitride layers into a single reaction chamber, eliminating the need for separate chambers. This merging approach reduces fabrication time by avoiding chamber transitions while maintaining contamination control through sequential deposition processes and in-situ treatments within the same controlled environment.
Solution Approach 2:
The patent applies in-situ treatments before and during deposition to prepare the substrate surface and control the deposition process. These preliminary actions ensure proper adhesion and uniformity of layers without requiring additional cleaning chambers, thus reducing overall fabrication time while maintaining reliability.
2Reliability
If separate deposition chambers are used to form titanium silicide and titanium nitride layers, then contamination is reduced, but device complexity increases
Solution Approach 1:
The patent merges multiple deposition processes into a single reaction chamber, reducing the number of equipment pieces and process steps. This simplifies the overall device fabrication process while maintaining contamination control through careful process sequencing and in-situ treatments within the unified chamber environment.
3Ease of manufacture
If conventional deposition methods are used, then fabrication process is simple, but layer conformality and uniformity in high aspect-ratio contact regions deteriorate
Solution Approach 1:
The patent modifies deposition parameters including gas flow rates, pressure conditions, and temperature profiles to achieve conformal and uniform layer deposition in high aspect-ratio contact regions. These parameter changes enable precise control over deposition kinetics, ensuring consistent film quality without complicating the overall fabrication process.
Solution Approach 2:
The patent employs continuous deposition processes with optimized gas delivery systems that maintain uniform reactant distribution throughout the reaction chamber. This continuous action ensures consistent layer formation across complex geometries, achieving high conformality while keeping the fabrication process straightforward.
4Ease of manufacture
If conventional deposition methods are used, then fabrication process is simple, but layer thickness control deteriorates
Solution Approach 1:
The patent utilizes precise control of deposition parameters such as gas flow rates, pressure, and temperature to achieve uniform layer thickness. By optimizing these parameters, the process maintains simplicity while achieving excellent thickness control through enhanced reaction kinetics and uniform reactant distribution within the single chamber.
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 method enhances the quality and coverage of titanium silicide and titanium nitride layers, reducing parasitic resistance and improving the performance of semiconductor devices by ensuring consistent layer thicknesses and conformal deposition.
Implementation Method 1
A CVD and in-situ treatment process is employed to form titanium silicide and titanium nitride layers
Implementation Method 2
Selective Formation Of Titanium Silicide and Titanium Nitride Byhydrogen Gas Control
Data Source
AI summary
The present disclosure relates to a method for fabricating a semiconductor structure. The method includes providing a substrate with a gate structure, an insulating structure over the gate structure, and a S/D region; depositing a titanium silicide layer over the S/D region with a first chemical vapor deposition (CVD) process. The first CVD process includes a first hydrogen gas flow. The method also includes depositing a titanium nitride layer over the insulating structure with a second CVD process. The second CVD process includes a second hydrogen gas flow. The first and second CVD processes are performed in a single reaction chamber and a flow rate of the first hydrogen gas flow is higher than a flow rate of the second hydrogen gas flow.