Vertical Interconnects Through Conductive Holes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Forming interconnects from an upper conductive level through multiple lower conductive levels to an underlying semiconductor substrate is challenging, as conventional approaches result in increased resistance due to serpentine routing around conductive wiring, leading to longer and higher resistance interconnects.
Innovation Solution
The integration of interconnects that pass through holes in conductive elements within intermediate conductive levels, allowing for direct coupling between upper and underlying structures while maintaining low resistance across all conductive levels, including Metal 0, Metal 1, and Metal 2 in CMOS configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If interconnects serpentine around conductive wiring within lower conductive levels, then the interconnects can be formed to connect upper and underlying structures, but the interconnects become long and have higher resistance
Solution Approach 1:
The patent transitions from two-dimensional serpentine routing within conductive levels to three-dimensional vertical routing through holes in conductive levels. Interconnects pass through holes in intermediate conductive levels (Metal 1, Metal 2) to directly connect upper conductive structures to underlying structures, eliminating the need for long serpentine paths and reducing resistance.
Solution Approach 2:
The patent creates localized holes in specific conductive levels where interconnects need to pass through, rather than using uniform serpentine routing throughout. This localized modification allows direct vertical connections at critical points while maintaining the integrity of the conductive levels for other routing functions.
2Loss of energy
If interconnects directly pass through underlying conductive levels, then the interconnects are short and have low resistance, but the wiring within the underlying conductive levels must serpentine around the interconnects and become lengthened
Solution Approach 1:
The patent uses vertical holes through conductive levels to create three-dimensional interconnect paths, allowing wiring to maintain shorter horizontal paths while interconnects provide vertical connections. This separates the routing functions: wiring stays in conductive levels for horizontal connections, while interconnects use holes for vertical connections.
Solution Approach 2:
The patent segments the connection path into separate functions: wiring handles horizontal connections within conductive levels, while interconnects handle vertical connections through holes. This segmentation allows each to be optimized independently, preventing wiring from needing to serpentine around interconnects.
3Length of moving object
If holes are formed through conductive elements in intermediate conductive levels, then direct coupling between upper and underlying structures is achieved, but the conductive elements having holes may have increased resistance
Solution Approach 1:
The patent modifies the parameters of conductive elements by creating holes of specific dimensions and filling them with low-resistance interconnect material. The hole size, shape, and filling process are controlled to ensure the interconnect material provides lower resistance than the original conductive element path would have required.
Solution Approach 2:
The patent creates composite structures where holes in conductive elements are filled with interconnect material, forming a composite conductor. This composite structure combines the structural support of the conductive element with the low-resistance electrical path of the interconnect material, achieving both mechanical integrity and low resistance.
Data Source
AI summary
Some embodiments include an apparatus having a well region extending into a semiconductor substrate. A first conductive element is over the well region, and a second conductive element is over the first conductive element. A hole extends through the first conductive element. A connecting element extends from the second conductive element to the well region, and passes through the hole.