Interrupted Sacrificial Lines for Low-Pitch Interconnections
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for forming interconnection lines on integrated circuits with a pitch of 90 nm or less are complex and costly due to the need for unidirectional masks, which prevent the formation of perpendicular connections, increasing process complexity and cost.
Innovation Solution
A method involving the formation of parallel sacrificial material lines with trenches and spacers, where the lines are interrupted to create connections between adjacent lines, allowing for the formation of interconnection lines with a low pitch using a reduced number of photolithography operations and masks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If unidirectional masks are used to achieve pitch of 90 nm or less, then manufacturing precision is improved, but device complexity increases due to inability to form perpendicular connections simultaneously
Solution Approach 1:
The mask pattern is segmented into parallel line portions with interruptions (openings) rather than continuous lines. This segmentation allows the same unidirectional mask to define both parallel interconnection lines and perpendicular connections through strategic placement of line interruptions, eliminating the need for additional masks and reducing process complexity while maintaining 90 nm pitch precision
Solution Approach 2:
The unidirectional mask serves multiple functions simultaneously: it defines parallel interconnection lines and creates perpendicular connections through interrupted line portions. This multi-functionality eliminates the need for separate masks for different connection types, reducing device complexity while achieving the required manufacturing precision
2Manufacturing precision
If unidirectional masks are used to achieve pitch of 90 nm or less, then manufacturing precision is improved, but production cost increases due to additional process constraints
Solution Approach 1:
The mask pattern is segmented into parallel line portions with interruptions (openings) rather than continuous lines. This segmentation allows the same unidirectional mask to define both parallel interconnection lines and perpendicular connections through strategic placement of line interruptions, eliminating the need for additional masks and reducing process complexity while maintaining 90 nm pitch precision
Solution Approach 2:
The unidirectional mask serves multiple functions simultaneously: it defines parallel interconnection lines and creates perpendicular connections through interrupted line portions. This multi-functionality eliminates the need for separate masks for different connection types, reducing device complexity while achieving the required manufacturing 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 method enables the formation of interconnection lines with a low pitch while reducing the complexity and cost associated with traditional techniques, achieving auto-alignment and efficient electrical connections between adjacent lines using fewer photolithography masks.
Implementation Method 1
removing the sacrificial material by etching
Implementation Method 2
depositing a layer of silicon oxide
Data Source
AI summary
The invention concerns a method comprising: forming a plurality of parallel lines (502, 504, 506) of a sacrificial material over a layer of conductive material (510) of an integrated circuit, said parallel lines being separated by trenches, at least one of said lines being interrupted along its length by an opening (516) dividing it into first and second line portions (504A, 504B) separated by a space (S); forming spacers (522, 524, 526, 528, 530) in said trenches on lateral sides of said line portions and filling at least a bottom part of said opening between the line portions; removing the sacrificial material by etching; and forming interconnection lines (302, 304A, 304B, 306A, 306B, 308, 310) of said conductive material based on a pattern defined by said spacers.