Semiconductor Wafer Double-Side Polishing Flatness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing semiconductor wafers struggle to achieve both global and local flatness simultaneously, requiring multiple polishing steps and resulting in suboptimal edge exclusion and flatness parameters.
Innovation Solution
A double-side polishing method using a polishing agent with a lower concentration of SiO2 (0.1-0.4% by weight) and an alkaline component (0.1-0.9% by weight), applied until the wafer center is 10-30 μm thinner than the carrier, to improve both global and local flatness without additional polishing steps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional polishing methods are used, then material removal is achieved, but global and local flatness cannot be improved simultaneously
Solution Approach 1:
The invention changes the chemical composition parameters of the polishing agent, specifically using a slurry with 0.1-0.4% SiO2 and 0.1-0.9% alkaline component, which enables simultaneous improvement of both global and local flatness during a single polishing step while maintaining high material removal rates
2Manufacturing precision
If multiple polishing steps are used to improve flatness, then manufacturing precision increases, but production time and complexity increase
Solution Approach 1:
The invention merges multiple polishing functions into a single polishing step by using a specifically formulated slurry that simultaneously achieves both global flatness (SBIR < 100 nm) and local flatness (PSFQR ≤ 35 nm), eliminating the need for sequential polishing steps and reducing production time
3Ease of manufacture
If conventional polishing agents are used, then polishing can be performed, but edge roll-off and edge exclusion remain problematic
Solution Approach 1:
The invention modifies the chemical parameters of the polishing agent by using low concentrations of SiO2 (0.1-0.4%) and alkaline components (0.1-0.9%), which enables precise control of material removal at the wafer edges, reducing edge roll-off and minimizing the edge exclusion area while maintaining overall polishing efficiency
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 significantly enhances global and local flatness, reducing edge roll-off and achieving favorable SFQR and SBIR values with a single polishing step, while maintaining a small edge exclusion area.
Implementation Method 1
Both sides of the semiconductor wafer are polished between an upper and a lower polishing plate with a polishing agent
Implementation Method 2
The polishing agent contains 0.1 to 0.4% by weight of SiO2 and 0.1 to 0.9% by weight of an alkaline component
Data Source
AI summary
A method for producing a semiconductor wafer. The method includes placing the semiconductor wafer in a cutout in a carrier. Both sides of the semiconductor wafer are polished between an upper and a lower polishing plate with a polishing agent until the thickness of the center of the semiconductor wafer is less than the thickness of the carrier and from 10 μm to 30 μm of semiconductor wafer material is removed. The polishing agent contains 0.1 to 0.4% by weight of SiO2 and 0.1 to 0.9% by weight of an alkaline component.