High-k Fin Isolation Segments for Uniform GAA Gate Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The semiconductor industry faces challenges in scaling down semiconductor integrated circuits (ICs) while maintaining gate control and reducing short-channel effects, which complicates the manufacturing process and increases costs.
Innovation Solution
The use of gate-all-around (GAA) transistors with high-k isolation regions formed by hafnium oxide and insertion layers, such as silicon oxide, through a chemical mechanical planarization (CMP) process that includes selective and non-selective stages to achieve uniformity and precise shaping of isolation regions, allowing for aggressive scaling without etching adjacent to gates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional isolation methods are used during scaling, then manufacturing process complexity increases, but gate control and short-channel effects deteriorate
Solution Approach 1:
The high-k isolation region is formed before gate formation, establishing the isolation structure in advance. This preliminary action defines the isolation region boundaries before the gate is created, eliminating the need for subsequent etching adjacent to the gate and simplifying the overall manufacturing process while maintaining precise gate control
Solution Approach 2:
The isolation region is segmented into a multi-layer structure with a first high-k material layer and a second high-k material layer with different dielectric constants. This segmentation allows each layer to be optimized for specific functions, improving gate control and electrical isolation while maintaining manufacturing feasibility
2Productivity
If feature size is reduced to improve production efficiency, then production cost decreases, but manufacturing process complexity increases
Solution Approach 1:
The high-k isolation region is formed before gate formation, establishing the isolation structure in advance. This preliminary action defines the isolation region boundaries before the gate is created, eliminating the need for subsequent etching adjacent to the gate and simplifying the overall manufacturing process while maintaining precise gate control
Solution Approach 2:
The patent utilizes materials with different dielectric constants (high-k materials) to create the isolation region. By changing the electrical parameter (dielectric constant) rather than relying on geometric scaling, the patent achieves effective isolation and gate control at reduced feature sizes without proportionally increasing process complexity
3Manufacturing precision
If high-k isolation regions are formed with multiple layers, then within-wafer and wafer-to-wafer uniformity improve, but manufacturing process steps increase
Solution Approach 1:
The patent utilizes materials with different dielectric constants (high-k materials) to create the isolation region. By changing the electrical parameter (dielectric constant) rather than relying on geometric scaling, the patent achieves effective isolation and gate control at reduced feature sizes without proportionally increasing process complexity
Solution Approach 2:
The CMP process automatically adjusts material removal based on the different dielectric constants of the layers. The process self-regulates to achieve the desired isolation region profile and uniformity across the wafer, reducing the need for additional process steps to correct uniformity issues
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 enables improved within-wafer, within-die, and wafer-to-wafer uniformity, reduces cell height, and maintains effective gate control, addressing the complexity and cost issues associated with scaling down semiconductor ICs.
Implementation Method 1
performing a chemical mechanical planarization (CMP) process to remove the capping layer and the upper portion of the high-k material and to define high-k isolation segments
Data Source
AI summary
Provided are semiconductor devices and methods for fabricating such devices. An exemplary method includes forming fin structures separated by an isolation material; depositing a high-k material over the fin structures and isolation material, wherein the high-k material includes lower portions located between fin structures and an upper portion located above the fin structures; depositing a topography-improving capping layer over the high-k material; performing a chemical mechanical planarization (CMP) process to remove the capping layer and the upper portion of the high-k material and to define high-k insulation segments.