Electrostatic Chuck Temperature Control for Plasma Chamber Cleaning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In plasma etching processes for semiconductor devices, the formation of deposits containing carbon and fluorine within the chamber of plasma processing apparatuses leads to a low removal rate when the electrostatic chuck is set to low temperatures, resulting in prolonged cleaning times and reduced throughput.
Innovation Solution
A plasma processing method that includes etching an etching target film using a fluorocarbon or hydrofluorocarbon gas at a temperature of the electrostatic chuck set to −30° C or lower, followed by a cleaning process using oxygen plasma at a temperature of the electrostatic chuck set to 0° C or higher, which increases the removal rate of deposits and shortens the cleaning time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the electrostatic chuck is set to low temperature (≤-30°C) during plasma etching, then the etching rate is increased, but the cleaning time becomes prolonged
Solution Approach 1:
The electrostatic chuck temperature is dynamically adjusted: maintained at low temperature (≤-30°C) during etching to maximize etching rate, then rapidly raised to high temperature (≥0°C) during cleaning to minimize cleaning time. This dynamic adjustment resolves the contradiction between etching efficiency and cleaning speed.
Solution Approach 2:
The electrostatic chuck undergoes periodic temperature changes corresponding to the cyclic nature of plasma processing (etching followed by cleaning). During etching phases, temperature is low; during cleaning phases, temperature is high. This periodic temperature control optimizes both etching rate and cleaning time.
2Loss of time
If the electrostatic chuck temperature is increased to improve deposit removal rate, then the cleaning time is shortened, but the etching rate decreases
Solution Approach 1:
The electrostatic chuck temperature is dynamically controlled to be high (≥0°C) during cleaning to minimize cleaning time, then lowered to low temperature (≤-30°C) during etching to maximize etching rate. This temporal separation of temperature conditions resolves the contradiction between cleaning speed and etching efficiency.
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 effectively increases the removal rate of deposits within the chamber, thereby reducing the overall cleaning time and improving the throughput of the plasma processing apparatus.
Implementation Method 1
the processing target object is placed on an electrostatic chuck of a stage provided within a chamber main body
Implementation Method 2
a processing gas is supplied into a chamber, and plasma is generated as the processing gas is excited
Implementation Method 3
the temperature control device is configured to adjust a temperature of an electrostatic chuck
Implementation Method 4
cleaning the inside of the chamber main body by generating plasma of a cleaning gas containing oxygen
Data Source
AI summary
A time period for cleaning performed to remove a deposit formed within a chamber main body can be reduced. A plasma processing method including the cleaning of an inside of the chamber main body of a plasma processing apparatus is provided. The method includes etching including a main etching of etching an etching target film of a processing target object placed on a stage in a low temperature by generating plasma of a processing gas containing a fluorocarbon gas and/or a hydrofluorocarbon gas; carrying-out the processing target object from a chamber; and cleaning the inside of the chamber main body by generating plasma of a cleaning gas in a state that a temperature of an electrostatic chuck is set to be high.