Wafer Rotation Mechanism for Uniform Cleaning and Plating
Solution Overview
Problem
In wafer cleaning and electroless plating processes, uneven dipping of wafers in cleaning fluids and retention of hydrogen gas on wafer surfaces lead to poor yield rates and uneven plating, respectively.
Innovation Solution
A wafer rotating apparatus with a roller and shaft gear system, driven by a power unit, ensures even dipping and gas removal by rotating the wafer, with optional friction-enhancing wrapping layers and stabilizing features like limiting slots and a handheld portion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the wafer is stationary during cleaning and plating processes, then the equipment structure is simple, but the wafer surfaces are unevenly dipped in cleaning fluid and plating solution, causing poor yield and uneven plating
Solution Approach 1:
The patent applies the dynamics principle by transitioning from a stationary wafer to a rotating wafer during cleaning and plating processes. The wafer rotation mechanism ensures uniform dipping of the wafer surface in cleaning fluid and plating solution, eliminating uneven treatment and improving manufacturing precision without excessive complexity.
Solution Approach 2:
The wafer serves itself by rotating during the cleaning and plating processes. The self-rotation mechanism allows the wafer to uniformly expose all its surfaces to the cleaning fluid and plating solution without requiring complex external handling equipment, thus improving treatment uniformity while keeping the device structure relatively simple.
2Manufacturing precision
If hydrogen gas is not removed from wafer surfaces during electroless plating, then the process is simple, but the plating fluid cannot attach sufficiently to wafer surfaces, causing uneven plating and reduced yield
Solution Approach 1:
The patent uses wafer rotation to dynamically remove hydrogen gas from the wafer surface during electroless plating. The rotation prevents gas accumulation and ensures continuous contact between the plating fluid and wafer surface, achieving uniform plated layer formation without requiring complex gas removal systems.
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
Enhances wafer yield by ensuring even fluid contact and gas removal, resulting in improved appearance and increased yield rates above 97% in both cleaning and electroless plating processes.
Implementation Method 1
The roller has a wrapping layer wrapping around the roller to increase friction between the roller and the edge of the wafer
Data Source
AI summary
A wafer rotating apparatus includes a base, a carrying device, a first shaft gear, a power unit, a roller, a second shaft gear and a driving assembly. The base has an accommodating space which the carrying device is disposed in to accommodate the wafer. The first shaft gear is disposed on a side surface of the base. The power unit is assembled to a top of the base and connected to the first shaft gear. The roller is located under the carrying device and supports an edge of the wafer. The second shaft gear is disposed on the side surface of the base and connected to the roller. The driving assembly is connected between the first shaft gear and the second shaft gear. The power unit provides a power through the first gear, the driving unit and the second shaft gear to drive the roller to rotate the wafer.