Large Diameter Silicon Single Crystal Growth Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods fail to produce silicon single crystals with favorable macroscopic and microscopic resistivity distribution, particularly for large diameter (111) silicon wafers, which are essential for cutting-edge devices using next-generation channel materials.
Innovation Solution
The Czochralski method is employed while applying a magnetic field to control the growth conditions, setting the diameter and growth axis orientation to promote (111) lateral growth, ensuring a ratio of 1096/D−(0.134×M+80×R)/D>0.7, where D is the crystal diameter, M is the magnetic field strength, and R is the rotation rate, resulting in a silicon single crystal with 70% or more of the surface area as lateral growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a silicon single crystal is grown by conventional Czochralski method without magnetic field control, then the growth process is simple, but the macroscopic radial distribution of resistivity is unfavorable and microscopic variation is high
Solution Approach 1:
The patent applies a magnetic field during the Czochralski growth process to control melt convection and solid-liquid interface morphology. By changing the physical parameter (magnetic field application), the patent achieves favorable macroscopic radial distribution of resistivity and reduced microscopic variation, resolving the contradiction between manufacturing precision and process simplicity
Solution Approach 2:
The patent establishes a quantitative relationship between growth parameters (diameter D, magnetic field strength M, rotation rate R) and growth quality through the formula 1096/D−(0.134×M+80×R)/D>0.7. This feedback mechanism allows precise control of lateral growth to achieve 70% or more of the crystal surface as lateral growth, improving resistivity distribution uniformity
2Area of stationary object
If the crystal diameter is increased to 300 mm or more for large diameter wafers, then the wafer area increases for better device integration, but the control of lateral growth and resistivity distribution becomes more difficult
Solution Approach 1:
The patent specifically addresses large diameter crystal growth (D≥300 mm) by incorporating the diameter parameter into the control formula 1096/D−(0.134×M+80×R)/D>0.7. The magnetic field strength and rotation rate are adjusted as functions of diameter to maintain optimal lateral growth control across different scale sizes
Solution Approach 2:
The patent introduces magnetic field control as an additional control dimension to manage the complexity of large diameter crystal growth. By adding magnetic field strength M as a controllable parameter, the system gains an extra degree of freedom to control lateral growth and resistivity distribution in large diameter wafers
3Manufacturing precision
If magnetic field strength is increased to control lateral growth, then the resistivity distribution improves, but the energy consumption and equipment complexity increase
Solution Approach 1:
The patent provides a quantitative formula 1096/D−(0.134×M+80×R)/D>0.7 that defines the optimal magnetic field strength M as a function of crystal diameter and rotation rate. This allows achieving favorable resistivity distribution with minimized magnetic field strength, thereby reducing energy consumption while maintaining manufacturing precision
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 approach enables the production of large diameter silicon single crystals with improved macroscopic radial distribution of resistivity and reduced microscopic variation, making the (111) silicon wafer suitable for high-yield miniaturization techniques and as a substrate for next-generation channel materials.
Implementation Method 1
pulling a silicon single crystal by Czochralski method while a magnetic field is applied to a raw material melt
Implementation Method 2
applying a magnetic field to control the growth conditions
Implementation Method 3
production of a silicon single crystal by Czochralski method
Implementation Method 4
growth of a silicon single crystal
Data Source
AI summary
A method of producing a silicon single crystal, including pulling a silicon single crystal by Czochralski method while a magnetic field is applied to a raw material melt, including: setting a diameter on pulling the silicon single crystal to 300 mm or more, setting a growth axis direction of the silicon single crystal to <111>, and growing the silicon single crystal so as to satisfy a relation of 1096/D−(0.134×M+80×R)/D>0.7, wherein D [mm] is the diameter on pulling the silicon single crystal, M [Gauss] is a central magnetic field strength at a surface of the raw material melt, and R [rpm] is a rotation rate of the silicon single crystal. This makes it possible to produce a <111> crystal with favorable macroscopic RRG distribution and microscopic variation of resistivity.