Substrate Drying Gas Filtration for 20 Nm Defect Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate drying technologies struggle to effectively suppress micro-sized defects (20 nm or less) on substrates with complex film structures, leading to issues like water marks and residue, which can impact semiconductor device reliability.
Innovation Solution
A substrate drying device and method that utilizes a controlled sequence of rinse liquid and drying gas application, including a filter with a defect size ratio of 4 or more, and a controlled nozzle movement and gas concentration to minimize defects by stopping rinse liquid supply and reducing drying gas flow at the substrate edge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional substrate drying device supplies rinse liquid and drying gas without regional control, then the entire substrate surface can be processed uniformly, but micro-sized defects occur on the substrate edge where centrifugal force is strong and rinse liquid remains
Solution Approach 1:
The patent applies local quality by dividing the substrate into different regions (center and edge) and applying different drying conditions to each region. Specifically, the drying gas flow rate is reduced in the edge region where centrifugal force is strong, while maintaining normal flow rate in the center region. This regional differentiation prevents excessive drying that would cause micro-defects at the edges while ensuring adequate drying at the center.
Solution Approach 2:
The patent employs dynamics by dynamically adjusting the drying gas flow rate based on the radial position on the substrate. The system transitions from a static, uniform drying approach to a dynamic, position-dependent approach where the gas flow rate varies continuously or in steps from the center to the edge, adapting to the varying centrifugal force distribution across the substrate surface.
2Object-affected harmful factors
If the drying gas flow rate is reduced at the substrate edge to suppress micro-defects, then defect occurrence is reduced, but the drying time may increase
Solution Approach 1:
The patent applies local quality by dividing the substrate into different regions (center and edge) and applying different drying conditions to each region. Specifically, the drying gas flow rate is reduced in the edge region where centrifugal force is strong, while maintaining normal flow rate in the center region. This regional differentiation prevents excessive drying that would cause micro-defects at the edges while ensuring adequate drying at the center.
Solution Approach 2:
The patent employs dynamics by dynamically adjusting the drying gas flow rate based on the radial position on the substrate. The system transitions from a static, uniform drying approach to a dynamic, position-dependent approach where the gas flow rate varies continuously or in steps from the center to the edge, adapting to the varying centrifugal force distribution across the substrate surface.
3Manufacturing precision
If a filter with small pore size is used to remove micro-particles, then particle removal efficiency is improved, but the filter clogs more easily and requires frequent maintenance
Solution Approach 1:
The patent applies segmentation by using a multi-stage filtration system with different filter elements having progressively smaller pore sizes. The first filter removes larger particles, the second filter removes medium-sized particles, and the third filter removes fine particles. This segmented approach achieves high particle removal efficiency while preventing any single filter from clogging too quickly, as each filter handles only the particle size range it is designed for.
Solution Approach 2:
The patent employs porous materials with specifically controlled pore size distributions in the filter elements. By selecting porous materials with appropriate pore sizes and distributions, the system achieves effective particle removal while maintaining adequate flow rates and resistance to clogging. The porous structure allows selective passage of particles based on size while maintaining filter longevity.
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
The method effectively suppresses micro-sized defects on the substrate edge, ensuring higher quality drying by minimizing defects to 20 nm or less, enhancing substrate reliability.
Implementation Method 1
supplying a drying gas including IPA vapor to a substrate to move rinse liquid from a center to an outer periphery with a Marangoni force
Implementation Method 2
move rinse liquid from a center to an outer periphery with a centrifugal force
Data Source
AI summary
A substrate drying device is provided that can suppress occurrence of a micro size defect (for example, a defect having a defect size of 20 nm or less). A substrate drying device 1 includes a substrate holding unit 11 which holds a substrate W, a gas generator 60 which generates a drying gas G including at least IPA vapor and for drying the substrate W, and a drying gas nozzle 30 which supplies the drying gas G to the surface WA of the substrate W. A filter 67 for filtering the drying gas G is provided in the gas generator 60. A defect size D allowed in a defect test after the drying of the substrate W is set to 20 nm or less and a ratio D/F of the defect size D and a filter size F of the filter 67 is set to 4 or more.