Process and apparatus for dry cleaning by photo-excited radicals
AssigneeFujitsu Limited
InventorRinshi Sugino
Life of this patent
Estimating the term…
Abstract
In a photo-excited dry cleaning with a halogen, a highly efficient radical generation can be obtained while selecting a cleaning gas or reaction gas pressure appropriate for removing contaminants from a substrate to be cleaned. This can be attained by controlling a light transmission distance or a distance from a window of a cleaning chamber through which a light enters the cleaning chamber to the substrate.
Claims19
A method for dry cleaning a substrate by placing the substrate in a cleaning chamber having a window transparent to a light, feeding a halogen-containing gas in the cleaning chamber, and irradiating the halogen-containing gas in the cleaning chamber with a light, the light passing through the window of the cleaning chamber toward the substrate, to generate halogen radicals and thereby clean the substrate, said method comprising the steps of
- a) determining relationships of an etching rate of a substrate with a distance from a window of a cleaning chamber to the substrate and with a pressure of a halogen-containing gas in the cleaning chamber,
- b) placing a substrate in the cleaning chamber such that the distance from the window of the cleaning chamber to the substrate is a first distance,
- c) feeding the halogen-containing gas in the cleaning chamber and adjusting a pressure of the halogen-containing gas such that an etching rate of the substrate is not less than 90% of a maximum etching rate at said first distance, and then
- d) irradiating the substrate with a light through the window to remove a portion of the substrate.
A method for dry cleaning a substrate by placing the substrate in a cleaning chamber having a window transparent to a light, feeding a halogen-containing gas in the cleaning chamber, and irradiating the halogen-containing gas in the cleaning chamber with a light the light passing through the window of the cleaning chamber toward the substrate, to generate halogen radicals and thereby clean the substrate, said method comprising the steps of
- a) determining relationships of an etching rate of a substrate with a distance from a window of a cleaning chamber to the substrate and with a pressure of a halogen-containing gas in the cleaning chamber,
- b) placing the substrate in the cleaning chamber,
- c) feeding the halogen-containing gas in the cleaning chamber such that a pressure of the halogen-containing gas in the cleaning chamber is a first pressure,
- d) adjusting a distance from the window of the cleaning chamber to the substrate such that an etching rate of the substrate is not less than 90% of a maximum etching rate at said first pressure, and
- e) irradiating the substrate with a light to remove a portion of the substrate.
A method for dry cleaning a substrate by placing the substrate in a cleaning chamber having a window transparent to a light, feeding a halogen-containing gas in the cleaning chamber, and irradiating the halogen-containing gas in the cleaning chamber with a light, the light passing through the window of the cleaning chamber toward the substrate, to generate halogen radicals and thereby clean the substrate, said method comprising the steps of
- a) determining relationships of a rate of removing a contaminant from a substrate with a distance from a window of a cleaning chamber to the substrate and with a pressure of a halogen-containing gas in the cleaning chamber,
- b) placing a substrate having the contaminant adhered on a surface thereof in the cleaning chamber such that the distance from the window of the cleaning chamber to the substrate is a first distance,
- c) feeding the halogen-containing gas in the cleaning chamber and adjusting a pressure of the halogen-containing gas such that a rate of removing the contaminant from the substrate is not less than 90% of a maximum removing rate at said first distance, and then
- d) irradiating the substrate with a light through the window to remove the contaminant from the substrate.
A method for day cleaning a substrate by placing the substrate in a cleaning chamber having a window transparent to a light, feeding a halogen-containing gas in the cleaning chamber, and irradiating the halogen-containing gas in the cleaning chamber with a light, the light passing through the window of the cleaning chamber toward the substrate, to generate halogen radicals and thereby clean the substrate, said method comprising the steps of
- a) determining relationships of a rate of removing a contaminant from a substrate with a distance from a window of a cleaning chamber to the substrate and with a pressure of a halogen-containing gas in the cleaning chamber,
- b) placing a substrate having the contaminant adhered on a surface thereof in the cleaning chamber,
- c) feeding the halogen-containing gas in the cleaning chamber such that a pressure of the halogen-containing gas in the cleaning chamber is a first pressure,
- d) adjusting a distance from the window of the cleaning chamber to the substrate such that a rate of removing the contaminant from the substrate is not less than 90% of a maximum removing rate at said first pressure, and
- e) irradiating the substrate with a light to remove the contaminant from the substrate.
An apparatus for dry cleaning a substrate, comprising:
- a cleaning chamber;
- means for mounting a substrate to be cleaned in said cleaning chamber;
- a window provided in said cleaning chamber, which window is transparent to a light;
- means for feeding a halogen gas to said cleaning chamber;
- means for evacuating said cleaning chamber;
- a light source for irradiating a substrate placed in said cleaning chamber, through said window;
- means for controlling a gas pressure in said cleaning chamber;
- and
- means for moving said mounting means for controlling a distance from said window to the substrate.
Dependencies are inferred from the claim text.