Seal Ring Fin Layout for Epitaxial Overgrowth Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increasing integration and miniaturization of semiconductor devices lead to challenges such as the single-channel effect and defects due to epitaxial overgrowth at the edges of device regions, particularly in FinFET structures, where residual source gases cause bridging between adjacent epitaxial elements.
Innovation Solution
The semiconductor device incorporates a seal ring structure with active fins extending in a direction different from the integrated circuit structure, utilizing a {100} crystal plane for epitaxial growth, which effectively consumes residual source gases and prevents overgrowth by forming a second epitaxial pattern with a larger cross-sectional area on the seal ring active fins.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the degree of integration of semiconductor devices is increased to improve performance, then the functionality and speed of the device are enhanced, but the transistor size must be decreased which causes a single-channel effect
Solution Approach 1:
The patent transitions from planar transistors to three-dimensional FinFET structures by extending the channel into the vertical dimension. The gate electrode wraps around three sides of the channel structure, providing better electrostatic control and preventing the single-channel effect while maintaining miniaturization for high integration.
2Reliability
If a seal ring is added to protect the internal chip region from moisture or cracks, then the reliability of the device is improved, but the device complexity increases
Solution Approach 1:
The seal ring structure is merged with the active fin structure, using the same epitaxial growth process and material layers. The seal ring active fins are formed simultaneously with the device active fins through a unified manufacturing process, reducing overall complexity while providing protection.
Solution Approach 2:
The seal ring structure serves multiple functions: it protects the internal chip region from moisture and cracks, consumes residual source gases to prevent epitaxial overgrowth, and maintains structural integrity. This multi-functionality reduces the need for separate protective components.
3Productivity
If epitaxial growth is performed to form source/drain regions, then the device functionality is improved, but residual source gases cause epitaxial overgrowth and bridging between adjacent elements
Solution Approach 1:
The seal ring active fins act as an intermediary structure that consumes residual source gases during epitaxial growth. By positioning the seal ring between the epitaxial growth zone and the external environment, it prevents harmful gases from causing overgrowth in the device region while allowing necessary growth to occur.
Solution Approach 2:
The patent converts the harmful residual source gases into a beneficial effect by directing them toward the seal ring active fins. The seal ring structure utilizes these residual gases for its own epitaxial growth, preventing them from causing unwanted bridging between adjacent device elements.
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 configuration enhances the reliability of semiconductor devices by preventing defects like bridge phenomena between epitaxial elements, ensuring effective epitaxial growth and reducing the risk of moisture penetration and crack formation.
Implementation Method 1
utilizing a {100} crystal plane for epitaxial growth, which effectively consumes residual source gases and prevents overgrowth by forming a second epitaxial pattern with a larger cross-sectional area on the seal ring active fins
Data Source
AI summary
A semiconductor device includes a substrate having a first region and a second region surrounding the first region, an integrated circuit structure disposed on the first region, and a seal ring structure disposed on the second region, wherein the integrated circuit structure includes a first active fin extending on the first region in a <110> crystal direction of the substrate, a first epitaxial pattern disposed on one region of the first active fin, and a first contact structure connected to the first epitaxial pattern, and the seal ring structure includes a second active fin extending on the second region in a <100> crystal direction of the substrate, a second epitaxial pattern disposed on the second active fin and including the same material as that of the first epitaxial pattern, and a second contact structure connected to the second epitaxial pattern.