Gate Extension Layout Pre-Distortion for OPE Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photolithographic processes in semiconductor manufacturing suffer from optical proximity effects (OPEs) that cause shape distortions in semiconductor devices, particularly in the formation of gate extensions, leading to over-etching and impaired functional connections between gate electrodes and underlying active regions.
Innovation Solution
A pre-distortion technique is applied to the layout diagram by widening the middle region of bridge segments in the line pattern to mitigate over-etch distortions, ensuring the resulting gate extensions maintain a rectangular shape and facilitate effective connections with underlying active regions, implemented during the design phase rather than through optical proximity correction (OPC).
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If optical proximity correction (OPC) is applied to correct layout distortions, then manufacturing precision is improved, but device complexity and process time increase
Solution Approach 1:
The patent applies pre-distortion to the layout diagram before photolithography, intentionally adding distortions that will be compensated during the etching process. This preliminary action eliminates the need for complex OPC calculations after layout generation, reducing process complexity while maintaining manufacturing precision for gate extension shapes
Solution Approach 2:
The patent introduces pre-calculated distortion patterns that counteract the expected over-etching effects. By applying the opposite distortion in advance, the final etched shape achieves the desired rectangular geometry without requiring complex real-time correction processes
2Manufacturing precision
If pre-distortion is applied to mitigate over-etch distortions, then manufacturing precision is improved, but layout design complexity increases
Solution Approach 1:
The patent applies pre-distortion selectively to specific regions of the layout diagram, particularly to bridge segments connecting gate electrodes to active regions. Instead of distorting the entire layout, only local areas prone to over-etching are modified, maintaining overall layout simplicity while achieving precise rectangular gate extension shapes
Solution Approach 2:
The patent modifies specific geometric parameters of the layout diagram, such as adjusting the width and positioning of bridge segments. These parameter changes are calculated to compensate for expected etching variations, transforming the layout to produce the desired rectangular gate extensions after etching without excessive complexity
3Reliability
If bridge segment width is increased to prevent over-etching, then reliability is improved, but area consumption increases
Solution Approach 1:
The patent pre-distorts the bridge segment dimensions in the layout diagram to account for expected etching shrinkage. This preliminary adjustment ensures that after etching, the bridge segments maintain adequate width for reliable functional connections without requiring excessive initial width that would waste layout area
Data Source
AI summary
A semiconductor structure includes first and second active regions extending in a first direction. The semiconductor structure further includes gate electrodes extending in a second direction perpendicular to the first direction. Each of the gate electrodes includes a first segment over at least one of the first active region or the second active region; a gate extension extending beyond each of the first active region and the second active region, wherein the gate extension has a uniform width in the first direction, and a conductive element, wherein a width of the conductive element in the first direction increases as a distance from the gate extension increases along an entirety of the conductive element in the second direction.