Shower Head Buffer Zones for Film Thickness Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The semi-batch type film forming apparatus experiences non-uniform film thickness distribution in the radial direction from the rotation center of the mounting table, necessitating an improvement in film thickness uniformity.
Innovation Solution
A film forming apparatus with a shower head featuring multiple buffer spaces and independently controllable flow rates for process gas injection, where the first injection ports are closer to the axis than the second injection ports, and an inert gas is optionally used to enhance gas flow management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a single buffer space with uniform gas supply is used in the shower head, then the device complexity is reduced, but the film thickness uniformity in the radial direction deteriorates
Solution Approach 1:
The shower head is divided into multiple buffer spaces (first buffer space and second buffer space) with different gas supply flow rates. Each buffer space has independent flow rate control, allowing differential gas distribution to achieve uniform film thickness across the substrate radial direction.
Solution Approach 2:
Different regions of the shower head are assigned different gas supply characteristics. The first buffer space (closer to center) and second buffer space (closer to periphery) have independently controlled flow rates, creating local quality variations that compensate for radial non-uniformity in film deposition.
2Manufacturing precision
If the gas supply flow rate is uniformly controlled across the shower head, then the ease of operation is improved, but the film thickness uniformity deteriorates
Solution Approach 1:
The gas supply system is segmented into multiple independently controlled flow rate controllers, each managing a specific buffer space. This segmentation enables precise local flow rate adjustment to achieve uniform film thickness, with each controller operating autonomously.
Solution Approach 2:
The flow rate parameter is varied across different buffer spaces rather than maintained uniformly. By changing the flow rate parameter locally in different regions, the system achieves uniform film deposition while maintaining operational control through automated flow rate management.
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 improves the uniformity of film thickness in the radial direction by controlling the flow rates and distribution of the precursor gas, ensuring consistent film deposition across the substrate.
Implementation Method 1
a substrate is exposed to a precursor gas so that the precursor gas containing a constituent element of a thin film is chemically adsorbed on the substrate
Implementation Method 2
the plasma generating unit supplies a reaction gas, and radiates microwaves supplied from a waveguide from a substantially fan-shaped antenna to generate the plasma of the reaction gas
Implementation Method 3
a mounting table configured to place a substrate to be processed thereon, and provided to be rotatable around an axis such that the substrate is moved around the axis
Implementation Method 4
a flow rate controller configured to independently control a flow rate of a process gas to be supplied to each of the first buffer space and the second buffer space
Data Source
AI summary
A film forming apparatus includes: a mounting table configured to place a substrate thereon and to be rotatable around an axis; a unit provided in a first region such that its bottom surface faces the mounting table and having first and second buffer spaces therein; and a flow rate controller that independently controls flow rates of a precursor gas supplied to the first and second buffer spaces. In the bottom surface, the unit includes: an inside injection section including injection ports communicated with the first buffer space and configured to inject the precursor gas supplied to the first buffer space; and an intermediate injection section including injection ports communicated with the second buffer space and configured to inject the precursor gas supplied to the second buffer space. All the first injection ports are provided at a location closer to the axis, as compared to the second injection ports.