Backside Power Rail and Interconnect Layout for Compact ICs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The miniaturization of integrated circuits poses challenges in design and manufacturing, including stricter specifications and reliability issues, particularly in ensuring consistent transistor characteristics and efficient power supply, which existing technologies struggle to address effectively.
Innovation Solution
The implementation of backside power rails and backside metal rails in integrated circuits, which provide reliable supply voltage and flexible routing, allowing for a reduction in front-side metal rails and via contacts, resulting in more consistent transistor characteristics and a smaller chip area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If miniaturization is pursued to reduce device size and power consumption, then device functionality and speed improve, but design and manufacturing specifications become stricter and reliability challenges increase
Solution Approach 1:
The patent introduces backside power rails and backside interconnect layers, utilizing the vertical dimension (substrate thickness) to add new interconnection pathways. This dimensional expansion allows power and signal routing to occur on both front and back sides of the substrate, effectively increasing the available interconnect space without increasing the chip footprint, thereby maintaining miniaturization benefits while improving reliability through enhanced power distribution.
2Reliability
If more metal rails and via contacts are added to improve power supply and routing, then power delivery and signal interconnection improve, but chip area increases and manufacturing complexity increases
Solution Approach 1:
By routing power rails and interconnects on the backside of the substrate, the patent utilizes the unused backside space for additional metal layers. This approach provides more interconnection pathways without consuming additional chip area, as the backside layers are formed within the existing substrate footprint. The front side remains available for active device regions while the backside accommodates power and interconnect structures.
Solution Approach 2:
The patent segments the interconnection function between front side and back side, with the front side dedicated to active devices and the back side dedicated to power rails and interconnects. This functional segmentation allows each side to be optimized independently, reducing the need for excessive via contacts and metal rails on the front side, thereby reducing overall chip area and manufacturing complexity.
3Reliability
If more metal rails and via contacts are added to improve power supply and routing, then power delivery and signal interconnection improve, but device complexity increases
Solution Approach 1:
The patent divides the interconnect system into front side and back side components, with each side performing specific functions. The backside is dedicated to power distribution and long-distance signal routing, while the front side handles local interconnections. This segmentation simplifies the overall design by clearly defining the roles of each layer, reducing the need for complex multi-layer interconnect structures on the front side, and thereby reducing manufacturing complexity.
Solution Approach 2:
By adding interconnect layers on the backside, the patent provides additional routing dimensions without increasing front side complexity. This allows complex routing functions to be distributed across multiple layers on the backside, keeping the front side structure simpler and easier to manufacture, while achieving the required power delivery and signal interconnection performance.
Data Source
AI summary
Disclosed embodiments herein relate to an integrated circuit including metal rails. In one aspect, the integrated circuit includes a first layer including a first metal rail and a second layer including a second metal rail, where the second layer is above the first layer along a first direction. In one aspect, the integrated circuit includes a third layer including an active region of a transistor, where the third layer is above the second layer along the first direction. In one aspect, the integrated circuit includes a fourth layer including a third metal rail, where the fourth layer is above the third layer along the first direction. In one aspect, the integrated circuit includes a fifth layer including a fourth metal rail, where the fifth layer is above the fourth layer along the first direction.