Waferless clean in dielectric etch process
AssigneeLam Research Corporation
InventorsShijian Li, David Carman, Chander Radhakrishnan
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Abstract
A system and method for a waferless cleaning method for a capacitive coupled plasma system. The method includes forming a protective layer on a top surface of an electrostatic chuck, volatilizing etch byproducts deposited on one or more inner surfaces of the plasma process chamber, removing volatilized etch byproducts from the plasma process chamber and removing the protective layer from the top surface of the electrostatic chuck. A capacitive coupled plasma system including a waferless cleaning recipe is also described.
Claims20
A controller for use with a plasma chamber that is configured as a capacitively coupled plasma system, the controller is configured for operating a waferless cleaning process of the plasma chamber, the controller comprising,
- logic for setting a temperature difference between an electrostatic chuck and an edge ring that surrounds the electrostatic chuck of the plasma chamber, the temperature difference maintains the electrostatic chuck at a lower temperature than the edge ring that surrounds the electrostatic chuck;
- logic for generating plasma using a first process gas containing a carbon component and fluorine component, the plasma is configured to form a protective layer on a top surface of the electrostatic chuck and volatize etch byproducts formed on one or more inner surfaces of the plasma chamber from prior etch operations of a wafer, wherein the one or more inner surfaces of the plasma chamber include the edge ring that is maintained at the set temperature difference, the carbon component is configured to assist in the formation of the protective layer while the fluorine component is configured to assist in volatizing of the etch byproducts;
- logic for controlling removal of volatilized etch byproducts from the plasma chamber;
- and
- logic causing removal of the protective layer from the top surface of the electrostatic chuck using a second process gas that includes oxygen or an oxygen containing compound.
A controller for operating with a plasma chamber that is configured as a capacitively coupled plasma system, the controller is configured with logic for controlling a waferless cleaning process of the plasma chamber, the controller comprising:
- logic for setting a temperature difference between an electrostatic chuck and an edge ring that surrounds the electrostatic chuck of the plasma chamber, the temperature difference maintains the electrostatic chuck at a lower temperature than the edge ring that surrounds the electrostatic chuck by at least 20 degrees Celsius;
- logic for causing generation of a plasma in the plasma chamber using a first process gas containing a carbon component and fluorine component, the plasma is configured to form a protective layer in-situ on a top surface of the electrostatic chuck while volatilizing etch byproducts formed on the edge ring from prior etch operations of one or more wafers in the plasma chamber, wherein the, the carbon component is configured to assist in the formation of the protective layer while the fluorine component is configured to assist in volatizing of the etch byproducts from the edge ring;
- logic for controlling removal of volatilized etch byproducts from the plasma chamber;
- and
- logic for causing removal of the protective layer from the top surface of the electrostatic chuck using a second process gas that includes oxygen or an oxygen containing compound after generating the plasma with the first process gas.
Dependencies are inferred from the claim text.