Shower Plate Pressure Control for Plasma Chamber Venting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional plasma processing apparatuses face issues with contamination of the shower plate and gas supply system interiors by foreign material particles during venting to atmosphere, leading to potential damage of the shower plate and increased venting time, which reduces productivity.
Innovation Solution
A plasma processing apparatus with a dual gas supply system that adjusts the flow rates of vent gases to maintain a positive pressure on the back side of the shower plate within its withstand pressure range, preventing contamination and reducing venting time by controlling the pressure differential between the processing chamber and the back side of the shower plate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If vent gas is supplied into the processing chamber to return it to atmospheric pressure, then the venting process is completed, but foreign material particles are flown up and scatter into the gas supply system and shower plate causing contamination
Solution Approach 1:
The patent applies preliminary anti-action by supplying processing gas from the gas supply system during the venting process. This creates a protective gas flow that prevents foreign material particles from entering the gas supply system and shower plate, thereby preventing contamination before it can occur
Solution Approach 2:
The patent uses processing gas as an intermediary substance between the vent gas and the gas supply system. The processing gas acts as a protective barrier that allows venting to proceed while preventing particle contamination of the gas supply components
2Object-affected harmful factors
If high pressure gas is supplied from the gas supply system during venting to prevent particle entry, then contamination is prevented, but the shower plate may be damaged due to excessive pressure differential
Solution Approach 1:
The patent applies dynamics by dynamically adjusting the gas supply flow rate during the venting process. The control unit gradually increases the processing gas flow rate as venting progresses, ensuring the pressure differential remains within safe limits while still preventing particle contamination
Solution Approach 2:
The patent changes the parameter of gas flow rate dynamically during venting. By adjusting the flow rate of processing gas based on the venting stage, the system maintains optimal protection against contamination while preventing excessive pressure that could damage the shower plate
3Productivity
If vent gas flow rate is increased to reduce venting time, then productivity improves, but foreign material particles are more vigorously scattered and contamination risk increases
Solution Approach 1:
The patent uses processing gas as an intermediary that counteracts the harmful effects of high-velocity vent gas. Even when vent gas flows at high rates to improve productivity, the processing gas creates a protective barrier that prevents particle scattering into the gas supply system
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 solution effectively prevents contamination of the shower plate and gas supply system while reducing the venting time, thereby enhancing the productivity of the apparatus by ensuring safe operation and efficient cleaning processes.
Implementation Method 1
a plasma processing apparatus which is provided with vent gas supply means for supplying vent gas and then returning the interior of a processing chamber to an atmospheric pressure state from a decompressed state
Data Source
AI summary
In a plasma processing apparatus provided with control means, gas supply means includes a first gas supply path for supplying a vent gas into a processing chamber by way of a shower plate and a second gas supply path for supplying a vent gas into the processing chamber without via the shower plate, and the control means is capable of adjusting a flow rate of the vent gas of at least one of the first and second gas supply paths in such a manner that a pressure on a back side of the shower plate becomes a pressure that is a positive pressure relative to a pressure in the processing chamber and less than a withstand pressure of the shower plate.