Plasma Gas Supply Segmentation for Rapid Stabilization

Solution Overview

Problem

The existing flow rate controllers in plasma processing apparatuses have an upper limit on controllable maximum output flow rate, leading to degraded control performance, increased processing time, and waste of processing gas due to the need for prolonged stabilization of additional gas at a first-out flow rate, which reduces throughput.

Innovation Solution

A method involving a gas supply system where the additional gas is filled at high pressure in a tube by closing a downstream valve, allowing for a large flow rate initiation without flow rate controller limitations, and stabilizing the gas concentration independently of processing gas supply, thereby reducing waste and improving throughput.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If the flow rate controller is designed with a large maximum output flow rate, then the additional gas can be supplied at a high flow rate to shorten stabilization time, but the control performance is degraded in the flow rate range required for processing

Engineering Contradiction:

Improvestabilization time of additional gasVSAvoidcontrol performance of flow rate

Core Design Contradiction:

Loss of timeVSMeasurement precision

Solution Approach 1:

The gas supply system is segmented into two independent channels: a processing gas supply channel with a first flow rate controller for precise control during processing, and an additional gas supply channel with a second flow rate controller for rapid filling. This segmentation allows each controller to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The additional gas is supplied and stored in the tube at a high flow rate before the actual plasma processing begins. This preliminary action pre-fills the tube with additional gas, so that when processing starts, the gas is already available and no time is lost during the processing phase for gas stabilization or supply.

Inventive Principle:

Principle #10Preliminary action

2Productivity

If the additional gas is supplied at a large flow rate to reduce stabilization time, then the throughput is improved, but the processing gas is wasted due to prolonged supply time before high frequency power is supplied

Engineering Contradiction:

Improvethroughput of plasma processingVSAvoidwaste of processing gas

Core Design Contradiction:

ProductivityVSLoss of substance

Solution Approach 1:

The gas supply system is segmented into two independent channels: a processing gas supply channel with a first flow rate controller for precise control during processing, and an additional gas supply channel with a second flow rate controller for rapid filling. This segmentation allows each controller to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The additional gas is supplied and stored in the tube at a high flow rate before the actual plasma processing begins. This preliminary action pre-fills the tube with additional gas, so that when processing starts, the gas is already available and no time is lost during the processing phase for gas stabilization or supply.

Inventive Principle:

Principle #10Preliminary action

3Duration of action of moving object

If the flow rate controller operates at its maximum output flow rate, then the additional gas supply time is shortened, but the control performance is degraded in the flow rate range needed for accurate processing control

Engineering Contradiction:

Improvetime to supply additional gasVSAvoidcontrol accuracy for processing

Core Design Contradiction:

Duration of action of moving objectVSEase of operation

Solution Approach 1:

The gas supply system is segmented into two independent channels: a processing gas supply channel with a first flow rate controller for precise control during processing, and an additional gas supply channel with a second flow rate controller for rapid filling. This segmentation allows each controller to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The additional gas is supplied and stored in the tube at a high flow rate before the actual plasma processing begins. This preliminary action pre-fills the tube with additional gas, so that when processing starts, the gas is already available and no time is lost during the processing phase for gas stabilization or supply.

Inventive Principle:

Principle #10Preliminary action

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 method enables rapid stabilization of additional gas at processing flow rate, minimizing gas waste and enhancing throughput by allowing a large flow rate initiation and independent filling of additional gas, overcoming the limitations of conventional flow rate controllers.

Implementation Method 1

a flow rate controller for controlling the flow rate of the additional gas

Methodology Applied

Scientific EffectFlow rate control:

Implementation Method 2

a valve provided between the flow rate controller and the second branch line

Methodology Applied

Scientific EffectValve control:

Implementation Method 3

a tube provided between the flow rate controller and the valve

Methodology Applied

Scientific EffectGas flow through conduit:

Implementation Method 4

when the gas is supplied into the processing container, a high frequency power is supplied to the upper electrode or the lower electrode. Accordingly, plasma of the gas is generated within the processing container

Methodology Applied

Scientific EffectPlasma generation: Plasma

Data Source

PatentUS9947510B2Method for supplying gas, and plasma processing apparatus

Publication Date: 2018.04.17 TOKYO ELECTRON LTD

AI summary

In the exemplary embodiment, a method for supplying a gas is provided. This method includes supplying a processing gas to each of a central gas inlet portion and a peripheral gas inlet portion through a first branch line and a second branch line; closing a valve at a downstream side in a gas line for an additional gas, and filling the additional gas in a tube between the valve and an upstream flow rate controller; opening the valve after filling the additional gas, and supplying a high frequency power to one of an upper electrode and a lower electrode from a high frequency power supply after opening the valve.