Vertical Gas Supply Duct for Uniform Semiconductor Film Deposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor heat processing apparatuses face challenges in achieving uniform film thickness and gas flow rate due to variations in the gap between the reaction tube and substrates, leading to non-uniform film deposition and increased particle contamination.
Innovation Solution
A heat processing apparatus with a gas supply duct integrally formed outside the reaction tube, featuring vertically arranged gas delivery holes that communicate with the duct, reduces the gap between the tube and substrates, allowing for increased hole diameters and stable gas flow, thereby improving planar uniformity and reducing particle contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a large number of holes are formed in a gas nozzle to decrease gas concentration variations, then film thickness uniformity is improved, but the pressure gradient in the vertical direction increases and product deposition on hole edges occurs
Solution Approach 1:
The gas supply structure transitions from a conventional horizontal nozzle configuration to a vertical gas supply duct arrangement. This dimensional change allows gas to be supplied from the bottom upward through the reaction tube, fundamentally altering the flow pattern and eliminating the pressure gradient issues associated with horizontal multi-hole nozzles while maintaining uniform gas distribution
Solution Approach 2:
The gas supply system is divided into multiple vertical ducts (first and second gas supply ducts) that are positioned at different locations within the reaction tube. Each duct independently supplies gas to specific regions, enabling segmented control of gas flow and concentration distribution throughout the reaction space, thereby achieving uniform film deposition without the harmful effects of single-nozzle multi-hole configurations
2Stress or pressure
If the opening diameters of holes in the gas nozzle are increased to decrease pressure gradient, then gas flow uniformity is improved, but the gap between reaction tube and substrates increases and planar uniformity degrades
Solution Approach 1:
The invention replaces the conventional horizontal nozzle with a vertical gas supply duct configuration. Gas flows upward from the bottom of the reaction tube through vertically oriented ducts, creating a fundamentally different pressure distribution pattern. This vertical arrangement naturally reduces pressure gradients without requiring large hole diameters, as the gas flow path is optimized by the vertical orientation and the spacing between the ducts and substrates is controlled to maintain appropriate gaps
Solution Approach 2:
Different regions of the reaction tube are served by different gas supply ducts positioned at specific locations. The first gas supply duct is positioned to supply gas to certain substrate regions while the second duct serves other regions, allowing localized optimization of gas flow characteristics. This segmented approach enables each duct to maintain appropriate pressure gradients and gap distances for its specific service area, achieving overall planar uniformity
3Manufacturing precision
If the reaction tube wall surface is projected outwardly to decrease the gap between tube and substrates, then planar uniformity is improved, but the pressure resistance of the reaction tube decreases and cleaning time prolongs
Solution Approach 1:
Instead of modifying the reaction tube wall geometry by projecting it outward, the invention introduces vertical gas supply ducts that extend downward to approach the substrates from below. This vertical gas supply approach achieves the desired proximity to substrates for uniform film deposition without altering the reaction tube's structural integrity. The ducts are positioned in the vertical dimension to minimize gaps while maintaining the reaction tube's original cylindrical shape and pressure resistance
Solution Approach 2:
The gas supply ducts act as intermediary structures that mediate between the gas source and the substrates. These ducts are positioned to provide close proximity to the substrates for uniform gas distribution, while the reaction tube maintains its original structure and pressure resistance. The ducts serve as the intermediate element that achieves the gap reduction goal without compromising the reaction tube's structural strength or cleaning accessibility
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 apparatus achieves improved planar uniformity of film thickness and stable gas flow, reducing the need for frequent cleaning and maintaining a low pressure atmosphere, which minimizes particle generation and extends processing time.
Implementation Method 1
a gas supply system connected to a bottom portion of the gas supply duct to supply a process gas to the process field through the gas supply duct and the gas delivery opening
Implementation Method 2
a heater configured to heat the target substrates in the process field
Implementation Method 3
an exhaust system configured to exhaust an interior of the process field
Implementation Method 4
a film formation process by a CVD process
Data Source
AI summary
A heat processing apparatus for a semiconductor process includes a reaction tube including a process field configured to store a plurality of target substrates stacked at intervals. A gas supply duct is integrally provided outside the wall of the reaction tube to extend vertically in a range that covers the process field. A plurality of gas delivery holes are formed in the side portion of the wall of the reaction tube, to be vertically arrayed in a range that covers the process field and communicate with the gas supply duct. A gas supply system is connected to a bottom portion of the gas supply duct to supply a process gas to the process field through the gas supply duct and the plurality of gas delivery holes.