Dielectric Fin Height Variation for Fin Isolation and Contact Area
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The scaling down of semiconductor integrated circuits poses challenges in manufacturing due to increased complexity and device performance degradation, particularly in field-effect transistors, where existing methods have not adequately addressed issues related to device sizes and fabrication costs.
Innovation Solution
The introduction of dielectric fin structures with varying heights and widths, integrated with semiconductor fin structures, to improve manufacturing processes by providing topography uniformity and isolating adjacent semiconductor fins, reducing coupling capacitance, and enhancing source/drain contact areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If semiconductor device sizes continue to decrease to increase functional density, then production efficiency increases and costs lower, but device performance degradation occurs and fabrication complexity increases
Solution Approach 1:
The patent implements dielectric fin structures with varying heights positioned between adjacent semiconductor fins, creating local topographic variations that provide electrical isolation and reduce coupling capacitance in specific regions without affecting overall device scaling. This local modification allows continued miniaturization while maintaining performance by addressing specific interference problems at fin interfaces.
Solution Approach 2:
The dielectric fin structures serve as intermediary elements between adjacent semiconductor fins, acting as isolation barriers that reduce parasitic coupling capacitance. These intermediate dielectric structures mediate the electromagnetic interaction between neighboring fins, enabling higher density integration while preserving individual fin performance characteristics.
2Ease of manufacture
If conventional fabrication methods are used for scaled devices, then manufacturing processes remain simple, but device performance degradation associated with various defects occurs
Solution Approach 1:
The dielectric fin structures are formed preliminarily between semiconductor fins during the fabrication sequence, establishing isolation barriers before subsequent processing steps. This preliminary formation of isolation structures prevents defects from developing during later manufacturing steps, addressing performance degradation issues before they occur in the fabrication process.
3Productivity
If adjacent semiconductor fins are placed closer together to increase density, then functional density increases, but coupling capacitance between fins increases causing performance degradation
Solution Approach 1:
Dielectric fin structures are positioned as intermediary elements between adjacent semiconductor fins, providing electrical isolation that reduces coupling capacitance. These intermediate dielectric structures enable higher fin density by blocking parasitic electromagnetic coupling while maintaining close spacing for increased functional density.
Solution Approach 2:
The varying heights of dielectric fin structures create local topographic variations that provide targeted electrical isolation between adjacent fins. This local modification of the interface environment reduces coupling capacitance in specific regions where fins are in close proximity, enabling higher density integration.
Data Source
AI summary
A semiconductor device includes a semiconductor fin structure extending in a first direction on a substrate and a first dielectric fin structure extending parallel to the fin structure, the first dielectric fin structure being underneath a gate structure extending in a second direction that is perpendicular to the first direction. The device further includes a second dielectric fin structure extending parallel to the fin structure, the second dielectric feature being positioned beneath a gate cut feature. A top surface of the first dielectric fin structure is higher than a top surface of the second dielectric fin structure.