Metal Layer End-Cut Flow for Precise Trench Patterning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor device patterning techniques suffer from large critical dimension variations and unacceptably large end-to-end spacing due to the inability to precisely control both width and length of features using a single patterning process, leading to increased complexity and reduced functional density in ICs.
Innovation Solution
A method involving two separate patterning processes is employed, where the first process defines the width of trenches in one direction and the second process defines the length in a perpendicular direction, allowing for precise control of both dimensions and filling the transformed trenches with conductive material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single patterning process is used to define both width and length of conductive features, then the process complexity is reduced, but the critical dimension uniformity deteriorates due to large CD variations
Solution Approach 1:
The single patterning process is segmented into two separate patterning processes: a first patterning process that defines the width of conductive features, and a second patterning process that defines the length. This segmentation allows each process to independently control one dimension, thereby achieving uniform critical dimensions without increasing overall process complexity.
2Productivity
If a single patterning process is used to define both width and length, then the number of process steps is reduced, but the end-to-end spacing becomes unacceptably large
Solution Approach 1:
The patterning process is divided into two independent steps where the first step establishes the width and the second step establishes the length. This independent control enables precise adjustment of end-to-end spacing between conductive features, reducing the spacing to acceptable levels while maintaining reasonable process efficiency through systematic fabrication steps.
3Device complexity
If the width and length of conductive features are defined in the same patterning process, then the process flow is simplified, but the functional density is reduced due to large end-to-end spacing
Solution Approach 1:
By segmenting the patterning into width-defining and length-defining steps, the process flow maintains clarity and systematic organization. The first patterning process creates features with controlled width, and the second patterning process controls the length and spacing, enabling higher functional density through reduced end-to-end spacing while preserving process flow manageability through structured fabrication sequences.
Data Source
AI summary
A method of patterning a metal layer is disclosed. The method includes providing a substrate and forming a material layer over the substrate. The method includes forming a second material layer over the first material layer. The method includes performing a first patterning process to the second material layer to form a trench in the second material layer. The first patterning process defines a width size of the trench, the width size being measured in a first direction. The method includes performing a second patterning process to the trench to transform the trench. The second patterning process defines a length size of the transformed trench. The length size is measured in a second direction different from the first direction. The method also includes filling the transformed trench with a conductive material.