PECVD Shower Head Thermal Expansion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing PECVD apparatuses face issues with non-uniform gas distribution due to thermal expansion-induced warping of the shower head, leading to uneven thin film deposition, particularly in large-scale manufacturing processes.
Innovation Solution
The apparatus incorporates a gas diffusion member with vertically penetrating gas guiding holes and a diffusion plate to ensure uniform gas distribution, coupled with a thermal resistance member and clamp system to minimize thermal expansion distortion of the shower head, maintaining even gas flow and deposition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a shower head is used in PECVD apparatus for gas distribution, then gas can be sprayed onto the substrate, but thermal expansion causes the shower head to warp and sag, resulting in non-uniform gas distribution
Solution Approach 1:
The shower head is divided into multiple independent support points (first support, second support, third support) distributed across its structure. This segmentation allows each support point to independently manage local thermal expansion, preventing cumulative warping and maintaining overall planarity for uniform gas distribution.
Solution Approach 2:
The support structure acts as a counterbalancing mechanism against the downward sagging force caused by thermal expansion. By providing upward support forces at multiple locations, the supports counterweight the thermal deformation, keeping the shower head in a stable, planar position.
2Manufacturing precision
If the shower head is supported to prevent warping, then gas distribution uniformity can be maintained, but the structural complexity increases
Solution Approach 1:
The support structure is designed to automatically adjust and maintain the shower head's position without requiring external control systems. The supports self-adjust to thermal expansion effects, providing a passive, self-regulating solution that maintains gas distribution uniformity without adding complex active control mechanisms.
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 configuration ensures a uniform large-area thin film deposition by minimizing thermal expansion distortion, resulting in improved process uniformity and quality.
Implementation Method 1
a gas diffusion member arranged below and separated from the gas inlet and coupled to the back plate by a first coupling member and configured to diffuse process gas supplied through the gas inlet
Implementation Method 2
the thermal deformation is caused by thermal expansion due to heat transfer from the high-temperature plasma and a heater (not shown) installed in the susceptor 2
Implementation Method 3
the sprayed gas is transformed to a state of plasma 8 by RF (Radio Frequency) power that is supplied through a plasma electrode 6
Implementation Method 4
the sprayed gas is transformed to a state of plasma 8 by RF (Radio Frequency) power that is supplied through a plasma electrode 6
Implementation Method 5
the thermal deformation is caused by thermal expansion due to heat transfer from the high-temperature plasma and a heater (not shown) installed in the susceptor 2
Implementation Method 6
any reaction gas remaining after completion of the thin film deposition process is discharged through an outlet pipe 9 by a vacuum pump (not shown)
Data Source
AI summary
An apparatus for chemical vapor deposition is disclosed. An aspect of the present invention provides an apparatus for chemical vapor deposition that includes: a process chamber configured to demarcate a reaction space; a back plate placed above the reaction space and having a gas inlet in a middle thereof; a gas diffusion member arranged below and separated from the gas inlet and coupled to the back plate by a first coupling member and configured to diffuse process gas supplied through the gas inlet; a shower head placed below and separated from the back plate and the gas diffusion member and having a middle part thereof coupled to the gas diffusion member by a second coupling member and having a plurality of spray holes perforated therein; and a susceptor arranged below and separated from the shower head and supporting a substrate. The gas diffusion member has a plurality of gas guiding holes that vertically penetrate the gas diffusion member such that the process gas supplied through the gas inlet is diffused toward a lower side of the gas diffusion member.