Common Etch Patterning for Gate and Source/Drain Contacts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methodologies require separate masking layers and etching processes to form gate and source/drain contact openings in integrated circuits, leading to increased manufacturing costs and complexity due to the need to avoid electrical shorts between gate and source/drain structures.
Innovation Solution
A common etch patterning process is employed to form both gate and source/drain contact openings simultaneously by creating a reduced-thickness gate cap layer and using a patterned masking layer to define openings through the insulating material, allowing for the formation of conductive contacts that avoid electrical shorts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate masking layers and etching processes are used to form gate and source/drain contact openings, then electrical shorts between gate and source/drain structures are avoided, but manufacturing cost and process complexity increase
Solution Approach 1:
The patent combines the formation of gate contact openings and source/drain contact openings into a single common etch patterning process. A first masking layer is used to define both gate contact regions and source/drain contact regions, allowing simultaneous formation of both types of contacts through one etching process, thereby reducing process complexity while maintaining electrical integrity through proper contact separation
Solution Approach 2:
The patent segments the contact formation process by using a first masking layer to define distinct gate contact regions and source/drain contact regions separately, even though they are formed in the same etching process. This segmentation ensures that gate contacts and source/drain contacts are formed in separate locations without electrical shorts, while still benefiting from the simplified single-process approach
2Reliability
If separate masking layers and etching processes are used to form gate and source/drain contact openings, then electrical shorts between gate and source/drain structures are avoided, but manufacturing cost increases
Solution Approach 1:
The patent merges the formation of gate contact openings and source/drain contact openings into a single common etch patterning process using one masking layer. This consolidation eliminates the need for separate masking and etching steps that would increase manufacturing cost, while still ensuring proper electrical isolation between gate and source/drain contacts through the defined contact regions
3Device complexity
If a common etch patterning process is used to form gate and source/drain contact openings simultaneously, then manufacturing cost and complexity are reduced, but the risk of electrical shorts between gate and source/drain structures increases
Solution Approach 1:
The patent segments the contact formation within the common etch process by using a first masking layer to define distinct gate contact regions and source/drain contact regions. This segmentation ensures that even though the etching process is common, the contacts are formed in separate, electrically isolated locations, preventing shorts while maintaining process simplicity
4Productivity
If a common etch patterning process is used to form gate and source/drain contact openings simultaneously, then manufacturing efficiency is improved, but the precision of contact opening formation may be compromised
Solution Approach 1:
The patent segments the masking layer into regions that define gate contact openings and source/drain contact openings with different dimensions and positions. The first masking layer is configured to define a first opening for the gate contact and a second opening for the source/drain contact, allowing precise control over each contact's geometry while still using a single etching process, thus maintaining both efficiency and precision
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 reduces manufacturing costs and complexity by enabling the simultaneous formation of gate and source/drain contact openings using a single masking layer, improving the efficiency of the process while maintaining electrical integrity.
Implementation Method 1
performing a common etching process sequence through a patterned masking layer to define a gate contact opening that extends through the reduced-thickness second portion of the gate cap layer and a plurality of separate source/drain contact openings
Data Source
AI summary
One method disclosed herein includes forming an opening in a layer of material so as to expose the source/drain regions of a transistor and a first portion of a gate cap layer positioned above an active region, reducing the thickness of a portion of the gate cap layer positioned above the isolation region, defining separate initial source/drain contacts positioned on opposite sides of the gate structure, performing a common etching process sequence to define a gate contact opening that extends through the reduced-thickness portion of the gate cap layer and a plurality of separate source/drain contact openings in the layer of insulating material, and forming a conductive gate contact structure and conductive source/drain contact structures.