Resistance Structure with Conductive Layer for IC Fabrication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional resistance structures in semiconductor integrated circuits face challenges in suppressing resistance value variations caused by potential differences between the semiconductor substrate and resistance elements, leading to inconsistency and reduced accuracy in resistance ratios, while also occupying excessive area due to the need for larger conductive layers.
Innovation Solution
A resistance structure comprising a conductive layer on a semiconductor substrate with first and second resistance elements having long and short sides, connected by wiring, and a connection portion to the conductive layer, which are fabricated to prevent potential differences-induced variations without increasing the occupancy area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the length dimension L and width dimension W of resistance elements are increased to suppress inconsistency and raise resistance ratio accuracy, then manufacturing precision is improved, but the area occupied by the resistance structure increases
Solution Approach 1:
The patent transitions from planar resistance element arrangement to a three-dimensional structure by forming resistance elements within a conductive layer that extends in the depth direction of the semiconductor substrate. This allows the resistance elements to utilize the vertical dimension, thereby achieving larger effective area without increasing the surface footprint, thus improving resistance ratio accuracy while maintaining compact occupancy area.
Solution Approach 2:
The patent embeds resistance elements within the conductive layer structure, where the resistance elements are formed inside or integrated with the conductive layer that itself is formed within the semiconductor substrate. This nested arrangement allows multiple functional components to occupy overlapping spatial regions, effectively increasing the resistance element dimensions without proportionally increasing the overall structure area.
2Reliability
If conductive layers are enlarged to prevent resistance value variations due to potential differences, then reliability is improved, but the area occupied by the resistance structure increases
Solution Approach 1:
The conductive layer is extended in the depth direction of the semiconductor substrate rather than only in the planar direction. By increasing the thickness or vertical extent of the conductive layer, the patent enhances the shielding effect against potential differences and improves resistance value stability without requiring a larger surface area, thus maintaining compact occupancy area while improving reliability.
3Device complexity
If a gap is provided between conductive layers to prevent short-circuit, then device complexity is reduced, but the resistance element becomes affected by electric fields from the semiconductor substrate causing resistance value changes
Solution Approach 1:
The patent utilizes the depth direction of the semiconductor substrate to position the conductive layer and resistance elements such that the vertical separation provides sufficient electrical isolation without requiring large lateral gaps. By arranging components in the vertical dimension, the patent maintains compact lateral dimensions while ensuring proper electrical isolation, thus reducing device complexity while maintaining resistance value stability.
Data Source
AI summary
A resistance structure including: a conductive layer provided at a surface layer portion of a semiconductor substrate; a first resistance element having long sides and short sides provided over the conductive layer with an insulating film interposed; a second resistance element having long sides and short sides provided over the conductive layer with the insulating film interposed and disposed such that one long side thereof opposes one long side of the first resistance element; first wiring that is connected to one end of the first resistance element; second wiring that is connected to one end of the second resistance element; third wiring that connects the other end of the first resistance element with the other end of the second resistance element; and a connection portion that connects any of the first wiring, the second wiring and the third wiring with the conductive layer.