Gate Endcap Isolation for Short Vertical Stacks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The scaling of multi-gate transistors in semiconductor devices poses challenges due to constraints on lithographic processes, leading to trade-offs between feature dimension and spacing, resulting in issues like metal in plug defects and increased overlap capacitance.
Innovation Solution
The implementation of a gate endcap isolation structure with a perpendicular grid of insulating material patterned before gate/contact definition, allowing for simultaneous patterning and trimming of plugs to avoid defects and reduce capacitance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If conventional lithographic processes are used to pattern multi-gate transistors, then feature dimension can be reduced, but spacing between features must be increased
Solution Approach 1:
The gate endcap isolation structure is formed preliminarily before the actual gate patterning step. This preliminary structure defines the exact location where gate endings should be, allowing subsequent lithographic steps to precisely pattern gates that terminate at the correct position without requiring excessive spacing for alignment tolerance.
Solution Approach 2:
The gate endcap isolation structure acts as an intermediary element between adjacent transistor gates. This intermediate structure provides a physical reference that mediates the spacing requirement, allowing gates to be positioned closer together while maintaining proper electrical isolation and alignment through the endcap structure.
2Length of stationary object
If gate endcap isolation structure is implemented, then spacing between features can be reduced, but manufacturing process complexity increases
Solution Approach 1:
The gate endcap isolation structure merges multiple functions into a single integrated feature: it provides electrical isolation between adjacent gates, defines the precise termination location for gates, and serves as an alignment reference for subsequent patterning steps. This consolidation reduces the need for separate structures and process steps.
Solution Approach 2:
The gate endcap isolation structure performs multiple functions simultaneously: it acts as an isolation barrier, a positioning template, and an alignment reference. This multi-functionality eliminates the need for separate dedicated structures for each function, simplifying the overall manufacturing process despite the reduced spacing.
Data Source
AI summary
Gate endcap architectures having relatively short vertical stack, and methods of fabricating gate endcap architectures having relatively short vertical stack, are described. In an example, an integrated circuit structure includes a first semiconductor fin along a first direction. A second semiconductor fin is along the first direction. A trench isolation material is between the first semiconductor fin and the second semiconductor fin. The trench isolation material has an uppermost surface below a top of the first and second semiconductor fins. A gate endcap isolation structure is between the first semiconductor fin and the second semiconductor fin and is along the first direction. The gate endcap isolation structure is on the uppermost surface of the trench isolation material.