CFET Termination Cell Layout for Lower Manufacturing Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing semiconductor integrated circuit devices using three-dimensional transistors face challenges in manufacturing variations and yield due to unaddressed structure and layout considerations of termination cells incorporating Complementary FETs (CFETs).
Innovation Solution
The semiconductor integrated circuit device incorporates a specific layout configuration with CFETs, where termination cells are arranged with dummy transistors and gate lines at the ends of cell rows, aligning with standard cells to regularize the layout pattern and interconnects, thereby reducing manufacturing variations and improving reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If termination cells are not specifically designed with dummy transistors and gate lines, then the layout can be simpler, but manufacturing variations increase and yield decreases
Solution Approach 1:
Dummy transistors and gate lines are arranged in termination cells before the actual manufacturing process to pre-establish a regularized layout pattern. This preliminary structural preparation ensures that the entire chip, including termination regions, maintains consistent spacing and alignment, thereby reducing manufacturing variations without adding complex functional elements.
Solution Approach 2:
The termination cells are designed to have the same structural characteristics as the standard logic cells, including the arrangement of gate lines, interconnects, and dummy transistors. This homogenization of layout patterns across different cell types ensures uniform manufacturing conditions and reduces variability, while the dummy elements maintain the regular spacing without contributing to logic functions.
2Reliability
If termination cells are not arranged with regularized layout patterns, then the design process is faster, but the finished shape variations and manufacturing variations increase
Solution Approach 1:
The dummy transistors and gate lines in termination cells serve multiple purposes: they maintain layout regularity, provide consistent spacing for manufacturing alignment, and enable standardized interconnect routing. This multi-functionality allows the same structural template to be applied across all cells, improving reliability through consistency while simplifying the overall design process by using a universal layout approach.
Solution Approach 2:
The successful layout pattern from standard logic cells is copied and applied to termination cells by incorporating dummy transistors and gate lines that replicate the spacing, alignment, and structural characteristics of functional cells. This copying of the proven layout template ensures that termination regions do not introduce manufacturing variations, thereby improving yield without requiring entirely new design methodologies.
3Speed
If three-dimensional transistors are used to improve integration degree and operating speed, then device performance improves, but off-current increases and power consumption increases
Solution Approach 1:
The three-dimensional transistor structure provides locally enhanced electric field control and carrier confinement in the channel region, which improves operating speed through better gate control. Simultaneously, the localized structural features such as strained semiconductor layers or specific doping profiles in the source/drain regions reduce off-state leakage current, thereby mitigating the power consumption increase while maintaining the speed improvement.
Data Source
AI summary
A cell row includes an inverter cell having a logic function and a termination cell having no logic function. The termination cell is arranged at one of two ends of the cell row. A gate line and dummy gate lines are arranged in the same layer in a Z direction. Local interconnects are arranged in the same layer in the Z direction. Local interconnects are arranged in the same layer in the Z direction.