Interconnection Structure With Stopping Pattern for Uniform Via-Line Profiles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The top-via module process for forming conductive patterns in integrated circuit devices results in non-uniform conductive line heights and profiles due to spacer variations, leading to resistance variations and performance deterioration.
Innovation Solution
Incorporating a stopping pattern between conductive lines and vias, aligned with their side surfaces, using materials with etch selectivity to ensure uniform widths and coplanar surfaces, such as ruthenium for conductive lines and tantalum nitride for stopping patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If top-via module process is used to form conductive patterns, then the process is simpler and more cost-effective, but the shapes, profiles, and heights of conductive lines show undesirable variations
Solution Approach 1:
A stopping pattern is introduced as an intermediary element between the conductive via and the conductive line. This stopping pattern serves as a reference structure during the recess process, enabling uniform removal of conductive material while preserving the underlying conductive line. The stopping pattern acts as a mediator that transfers the uniformity requirement from the final conductive line to the patterning process, resolving the contradiction between process simplicity and manufacturing precision.
2Ease of manufacture
If etching process is used in top-via module process, then the process can be implemented, but spacers on conductive patterns have various heights and profiles causing non-uniform conductive lines
Solution Approach 1:
The stopping pattern is formed in advance before the recess process that removes upper portions of conductive patterns. This preliminary structure provides a uniform reference level that guides the etching process, ensuring that all spacers are removed to the same height regardless of their initial variations. The pre-formed stopping pattern compensates for the lack of uniformity introduced by the etching process.
3Productivity
If recess process is used to remove upper portions of conductive patterns, then conductive lines and vias are formed, but non-uniform heights and profiles are caused
Solution Approach 1:
The stopping pattern serves as a mediator during the recess process, providing a uniform reference plane that ensures consistent removal of conductive material. By introducing this intermediary structure, the recess process can proceed uniformly across all conductive patterns, transforming a precision-critical step into a controlled material removal process that achieves both productivity and uniformity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach achieves uniform interconnection structures, reducing resistance variations and improving the performance consistency of integrated circuit devices.
Implementation Method 1
The stopping pattern may have an etch selectivity with the conductive via. The stopping pattern may have an etch selectivity with (with respect to) the lower conductive line
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
According to some embodiments of the inventive concepts, an integrated circuit device may be provided. The integrated circuit device may include a lower conductive line, a conductive via on the lower conductive line and a stopping pattern between the lower conductive line and the conductive via. A side surface of the stopping pattern may be aligned with the side surface of the lower conductive line and the side surface of the conductive via.