Plating Apparatus with Rectifying Plate for Uniform Film Thickness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electroless plating methods face challenges in achieving uniform film thickness across semiconductor substrates due to non-uniform supply of plating solutions and the presence of by-products, which affect the electroless plating solution's precipitation ratio and lead to local variations in reaction conditions.
Innovation Solution
An apparatus is designed with a rotatable holding mechanism, fluid supply units, and a gas supply system that includes a rectifying plate with holes to control the temperature and flow of nonreactive gas, ensuring uniform plating solution distribution and suppressing the influence of by-products, thereby maintaining a consistent film thickness across the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If electroless plating solution is supplied onto the substrate surface to form cap metal, then the EM tolerance of the semiconductor device is enhanced, but the plating solution cannot be uniformly distributed due to by-products and surface heterogeneity, resulting in non-uniform film thickness
Solution Approach 1:
A gas circulation system with inert gas (nitrogen or carbon dioxide) is introduced as an intermediary medium to remove by-products from the substrate surface during electroless plating. The gas circulation unit creates a controlled atmosphere that prevents by-product accumulation, enabling uniform plating solution distribution and achieving both high EM tolerance and uniform film thickness
Solution Approach 2:
The invention changes the physical and chemical parameters of the plating environment by controlling gas flow rate, gas temperature, and atmospheric composition. By adjusting these parameters, the system optimizes the removal of by-products while maintaining appropriate conditions for uniform cap metal deposition, resolving the contradiction between reliability enhancement and manufacturing precision
2Productivity
If by-products are allowed to remain on the substrate surface during plating reaction, then the plating process continues, but the by-products impede uniform liquid flow and prevent replacement of deteriorated plating solution, making uniform film formation impossible
Solution Approach 1:
Inert gas serves as an intermediary cleaning medium that continuously removes by-products from the substrate surface during the plating process. This allows the plating reaction to continue without interruption while maintaining surface conditions suitable for uniform film formation, thus preserving both productivity and manufacturing precision
Solution Approach 2:
The gas circulation system operates continuously throughout the plating process, maintaining constant removal of by-products. This continuous action ensures that the plating solution can uniformly contact the substrate surface throughout the entire process, enabling both continuous production and uniform film thickness
3Adaptability or versatility
If the substrate surface has locally hydrophilic or hydrophobic regions due to wiring density variations, then the plating solution flow becomes non-uniform, but uniform cap metal formation is required
Solution Approach 1:
Inert gas acts as a mediator that uniformly distributes plating solution across the substrate surface regardless of local hydrophilic or hydrophobic regions. The gas flow pattern ensures consistent solution delivery to both hydrophilic and hydrophobic areas, enabling uniform cap metal formation on heterogeneous surfaces with varying wiring densities
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 apparatus effectively reduces the amount of electroless plating solution used and ensures a uniform film thickness on the substrate by controlling gas flow and temperature, enhancing the reliability of the plating process.
Implementation Method 1
a gas supply device configured to generate a nonreactive gas and control a temperature of the nonreactive gas
Implementation Method 2
a rectifying plate disposed above the substrate and below the plurality of gas inlet openings inside the inner chamber. In the apparatus, the rectifying plate has a plurality of rectifying holes uniformly disposed in the rectifying plate
Implementation Method 3
the precipitation ratio of metal is largely affected by reaction conditions such as the composition and the temperature of the plating solution
Data Source
AI summary
An apparatus for a plating process includes: an outer chamber; an inner chamber covered by the outer chamber; a rotatable holding mechanism configured to hold a substrate horizontally and installed in the inner chamber; a fluid supply unit configured to supply a plating solution to a preset position on the substrate; a gas supply device configured to generate a nonreactive gas and control a temperature of the nonreactive gas; a gas supply hole configured to supply the nonreactive gas into the outer chamber and provided in a top surface of the outer chamber; a plurality of gas inlet openings provided at a sidewall of the inner chamber and spaced apart at equal distances; and a rectifying plate disposed above the substrate and below the plurality of gas inlet openings inside the inner chamber, the rectifying plate having a plurality of rectifying holes uniformly disposed in the rectifying plate.