MIM Capacitor Etching Structure to Break Sidewall Leakage Paths
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the etching process of metal-insulator-metal (MIM) structures in semiconductor devices, metal deposition on the sidewalls of the insulator layer can form leakage paths between the metal layers, compromising the insulation and device performance.
Innovation Solution
The semiconductor device employs a one-step etching process that includes etching the hard mask layer, top electrode layer, insulator layer, bottom electrode layer, and bottom electrode via in the same chamber with controlled parameters, which helps in retracting the top and bottom electrode layers and breaking any potential leakage paths formed by re-deposit metal at the sidewalls of the insulator layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If metal layers are etched in one etching process to form the MIM structure, then manufacturing efficiency is improved, but metal deposition on the sidewall of the insulator layer forms leakage paths connecting the two metal layers
Solution Approach 1:
The patent converts the harmful metal deposition on the insulator sidewall into a beneficial feature by designing the insulator layer to protrude beyond the metal layers. The protruding insulator portion acts as a protective barrier that prevents leakage paths, transforming the potential defect of metal deposition into an advantage by ensuring the insulator extends further laterally to block any leakage routes while maintaining process efficiency.
Solution Approach 2:
The patent applies preliminary action by forming the insulator layer with a protruding structure before the etching process. This pre-configured protruding shape ensures that when metal layers are etched in the same process, the insulator is already positioned to prevent metal deposition from creating leakage paths, thus preventing the reliability issue before it occurs.
2Reliability
If the insulator layer is formed with a protruding shape to prevent leakage paths, then insulation reliability is improved, but the device structure becomes more complex
Solution Approach 1:
The patent applies segmentation by dividing the insulator layer into distinct functional zones: a protruding portion that extends beyond the metal layers to provide leakage protection, and a main body portion that maintains the standard MIM structure. This segmentation allows the protruding feature to serve its protective function without requiring complete structural redesign of the entire device.
Solution Approach 2:
The patent applies local quality by making the insulator layer protrude only in specific lateral regions where leakage prevention is needed, while maintaining the standard structure in other areas. This localized modification ensures improved reliability at critical interfaces without unnecessarily complicating the entire device structure.
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 effectively breaks the leakage paths and maintains the insulation between the top and bottom electrode layers, ensuring the integrity and performance of the MIM structure in semiconductor devices.
Implementation Method 1
The metal layers and the insulator layer may be etched in one etching process to form the MIM structure
Implementation Method 2
when etching metal layers, the metal may be deposited on the sidewall of the insulator layer and form a leakage path connecting the two metal layers
Data Source
AI summary
A semiconductor device and a manufacturing method thereof are provided. The semiconductor device includes a top electrode layer, a bottom electrode layer, an insulator layer and a hard mask layer. The insulator layer is disposed between the top electrode layer and the bottom electrode. The top electrode layer, the insulator layer and the bottom electrode layer form a metal-insulator-metal structure. The hard mask layer stacks on the top electrode layer. The insulator layer protrudes from a first sidewall of the top electrode layer and a second sidewall of the bottom electrode layer.