Mixed Diffusion Break Isolation for Standard Cell Area Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional standard cell device architectures with diffusion breaks face area penalties and reduced output due to shallow and narrow single diffusion breaks, while deeper and wider double diffusion breaks increase area usage and transistor spacing, necessitating a more efficient isolation method.
Innovation Solution
A standard cell device architecture incorporating mixed diffusion break isolation trenches, featuring single diffusion breaks within the cell interior and double diffusion breaks at the cell edges, optimizing area utilization and output performance by combining shallow and narrow single trench isolation with deeper and wider double trench isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If single diffusion breaks are used for isolation, then area usage is minimized, but electrical isolation effectiveness and drive strength are reduced
Solution Approach 1:
The diffusion break is segmented into two distinct parts: a shallow single diffusion break portion and a deeper double diffusion break portion. This segmentation allows each part to serve different functions - the shallow portion minimizes area while the deeper portion provides effective electrical isolation, resolving the contradiction between area efficiency and isolation effectiveness.
Solution Approach 2:
Different depths and structures are applied to different portions of the diffusion break. The single diffusion break portion uses shallower trenches for area efficiency, while the double diffusion break portion uses deeper trenches for enhanced electrical isolation. This local differentiation of quality allows the system to optimize both area usage and isolation effectiveness in different locations.
2Reliability
If double diffusion breaks are used for isolation, then electrical isolation effectiveness is improved, but area penalties and transistor spacing increase
Solution Approach 1:
The diffusion break structure is divided into segments with different depths. The double diffusion break portion provides the necessary electrical isolation effectiveness, while the single diffusion break portion reduces the overall area penalty. This segmentation allows the system to achieve effective isolation without uniformly applying the area-intensive double diffusion break structure throughout.
Solution Approach 2:
The invention applies different diffusion break depths locally - deeper double diffusion breaks where electrical isolation is critical, and shallower single diffusion breaks where area efficiency is prioritized. This local quality differentiation resolves the contradiction by providing enhanced isolation only where necessary rather than uniformly across the entire device.
3Reliability
If deeper and wider double diffusion breaks are used, then electrical isolation is enhanced, but transistor spacing and device area increase
Solution Approach 1:
The diffusion break is segmented into shallow and deep portions, allowing enhanced electrical isolation to be achieved through the deeper double diffusion break portion without requiring uniformly increased spacing across all transistors. The shallow single diffusion break portions maintain tighter spacing where full isolation depth is not required.
Solution Approach 2:
Different diffusion break depths are applied locally to different transistor regions. Areas requiring enhanced electrical isolation receive the deeper double diffusion breaks, while other areas utilize shallower single diffusion breaks that allow for reduced transistor spacing, thus resolving the contradiction between isolation enhancement and spacing reduction.
Data Source
AI summary
A standard cell IC includes pMOS transistors in a pMOS region of a MOS device. The pMOS region extends between a first cell edge and a second cell edge opposite the first cell edge. The standard cell IC further includes nMOS transistors in an nMOS region of the MOS device. The nMOS region extends between the first cell edge and the second cell edge. The standard cell IC further includes at least one single diffusion break located in an interior region between the first cell edge and the second cell edge that extends across the pMOS region and the nMOS region to separate the pMOS region into pMOS subregions and the nMOS region into nMOS subregions. The standard cell IC includes a first double diffusion break portion at the first cell edge. The standard cell IC further includes a second double diffusion break portion at the second cell edge.