Semiconductor Contact Structure With Stacked Layers
Solution Overview
Problem
The existing semiconductor structures face poor electrical connection performance due to a small contact area between the contact structure and the electrical connection layer, leading to increased contact resistance and potential disconnection issues caused by alignment deviations during the manufacturing process.
Innovation Solution
The semiconductor structure incorporates a contact structure with a first contact layer and a second contact layer, where the second contact layer has a greater width than the first, increasing the contact area with the electrical connection layer and reducing resistance, while also providing a larger process window to mitigate alignment-related issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a contact structure with a single contact layer is used, then the manufacturing process is simple, but the electrical connection performance is poor due to small contact area and high contact resistance
Solution Approach 1:
The contact structure is divided into multiple contact layers (first contact layer and second contact layer) with different functions. The first contact layer provides mechanical support and initial electrical connection, while the second contact layer provides a larger contact area with the electrical connection layer, reducing contact resistance and improving electrical connection performance.
Solution Approach 2:
The contact structure transitions from a two-dimensional planar contact to a three-dimensional stacked structure. By adding the vertical dimension with multiple contact layers of different widths, the total contact area is increased without expanding the lateral footprint, effectively reducing contact resistance while maintaining device integration.
2Reliability
If the contact area between contact structure and electrical connection layer is small, then the device integration is high, but the contact resistance increases and disconnection issues occur
Solution Approach 1:
The contact structure is segmented into multiple layers where the second contact layer has a larger width than the first contact layer. This segmentation allows the electrical connection layer to contact multiple contact surfaces, effectively increasing the total contact area and reducing contact resistance without compromising device integration.
Solution Approach 2:
The contact structure uses a nested configuration where the first contact layer is positioned within the lateral footprint of the second contact layer. This nesting arrangement maximizes the contact area with the electrical connection layer while maintaining a compact structure that does not increase the overall device area.
3Manufacturing precision
If a narrow contact structure is used to maintain high device integration, then the feature size is reduced, but the alignment precision during manufacturing becomes more difficult to control
Solution Approach 1:
The contact structure is segmented into two layers with different widths. The first contact layer has a narrower width for high integration, while the second contact layer has a wider width that provides a larger target area for alignment during electrical connection layer formation, improving manufacturing precision without sacrificing device integration density.
Solution Approach 2:
The solution moves from a single-width contact structure to a multi-level contact structure. By utilizing the vertical dimension and creating contact layers of different widths at different heights, the design achieves both high integration (narrow first contact layer) and improved alignment precision (wider second contact layer) simultaneously.
Data Source
AI summary
Provided are semiconductor and a method for manufacturing semiconductor. The semiconductor structure includes: a substrate and a gate located on the substrate, a source is formed in the substrate on one side of the gate, and a drain is formed in the substrate on another side of the gate; a dielectric layer covering a surface of the gate; a contact structure passing through the dielectric layer and electrically connected to the source or the drain, the contact structure including a stack of a first contact layer and a second contact layer, and in a direction from the source to the drain, a width of the second contact layer being greater than a width of the first contact layer; and an electrical connection layer located at a top surface of the dielectric layer and in contact with part of a top surface of the second contact layer.