Silicon Core Wire Holder with Slit Gap for Polysilicon Growth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional core wire holders used in polycrystalline silicon manufacturing by the Siemens method face challenges such as non-uniform heat generation and electric discharge, leading to silicon core wire instability and potential falling, especially at the initial stage of deposition, which restricts the growth rate and productivity.
Innovation Solution
A core wire holder design featuring a slit-like gap part and a fixing member that securely fastens the silicon core wire, ensuring uniform thermal and electrical contact, reducing the likelihood of electric discharge, and enhancing the holding strength symmetrically.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the source gas is supplied at a high flow rate or high concentration from the initial stage of growth to increase the growth rate, then productivity is improved, but the silicon core wire is likely to fall due to insufficient joint strength
Solution Approach 1:
The patent applies preliminary action by pre-forming a recessed portion in the core wire holder before inserting the silicon core wire. This recessed portion is specifically designed to receive and secure the end of the silicon core wire, creating a pre-established mechanical interlock that prevents wire falling even when high growth rates are achieved through high source gas flow rates or concentrations from the initial stage of growth.
2Device complexity
If the silicon core wire is held in a conventional core wire holder, then the holder structure is simple, but non-uniform heat generation and electric discharge occur leading to wire instability
Solution Approach 1:
The patent applies local quality by creating a recessed portion at the specific location where the silicon core wire is inserted. This localized structural modification concentrates the holding function at the wire insertion point, ensuring uniform thermal and electrical contact between the wire and holder. The recessed portion design eliminates non-uniform heat generation and prevents electric discharge by ensuring consistent contact, thereby improving wire stability without significantly increasing overall device complexity.
3Ease of manufacture
If the silicon core wire is inserted into a core wire holder without a recessed portion, then the insertion process is simple, but the joint strength between wire and holder is insufficient
Solution Approach 1:
The patent applies preliminary action by pre-forming a recessed portion in the core wire holder before wire insertion. This recessed portion is specifically designed to receive and secure the end of the silicon core wire, creating a pre-established mechanical interlock that significantly enhances joint strength. The design maintains ease of manufacture as the recessed portion can be formed through standard machining processes, and the wire insertion remains a straightforward process of placing the wire end into the pre-formed recess.
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 improved holder design facilitates uniform polycrystalline silicon deposition, reduces the risk of core wire falling, and allows for increased productivity by enabling higher source gas flow rates and concentrations without compromising the core wire's stability.
Implementation Method 1
the core wire holder fixed to the metal electrode is also cooled by the metal electrodes
Implementation Method 2
A current is conducted from the metal electrode, and while the silicon core wire is being heated to a temperature in a range of 900°C~1200°C in a hydrogen atmosphere
Implementation Method 3
polycrystalline silicon is vapor-grown on a surface of the silicon core wire through a CVD (Chemical Vapor Deposition) process
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
A core wire holder 20 is formed with a core wire insert hole 21 having an opening part 22 on an upper surface of a main body and extending toward a lower surface side, and a silicon core wire 5 is inserted into the core wire insert hole 21. In addition, a slit-like gap part 60 extending along a virtual plane P including a central axis C of the core wire insert hole 21 is formed, and the slit-like gap part 60 is a gap part extending from the core wire insert hole 21 to reach an outer surface of the main body of the holder 20. The silicon core wire 5 inserted in the core wire insert hole 21 is fixed by fastening an upper part of the main body of the holder 20 from sides with, for example, a bolt/nut type fixing member 31.