Cleaning method and cleaning apparatus

Abstract

A method of cleaning an object in a processing chamber by supplying a supercritical fluid with an additive and rinsing the object with the supercritical fluid alone includes the steps of: opening a back-pressure valve of a branch pipe branched from an additive pipe on the rinse processing; and purging a residual additive from the additive pipe by circulating the supercritical fluid alone into the additive pipe and the branch pipe.

Description

CROSS REFERENCES TO RELATED APPLICATIONS[0001]The present invention contains subject matter related to Japanese Patent Application JP 2006-189553 filed in the Japanese Patent Office on Jul. 10, 2006, the entire contents of which being incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a cleaning method and a cleaning apparatus using a supercritical fluid, applicable to cleaning of semiconductor substrates in a semiconductor manufacturing process or cleaning of substrates in a process of manufacturing a photo-mask or a liquid-crystal display substrate, for example.[0004]2. Description of the Related Art[0005]In most of semiconductor apparatus manufacturing processes, for example, patterning processes for forming electrodes of desired shapes of planes, wiring patterns and contact holes are carried out by etching patterns on an electrode layer, a wiring layer, an insulating layer and the like deposited on a ...

AI Technical Summary

Benefits of technology

[0032]It is desirable to provide a cleaning method and a cleaning apparatus in which additives remaining within pipes can be purged sufficiently after a wafer is cleaned.

[0040]In the cleaning method and the cleaning apparatus according to the embodiments the present invention, the residual additive can be sufficiently purged from the additive pipe. Therefore, when a pressure in the substrate cleaning bath is reduced (when the pressure in the substrate cleaning bath is returned to an atmospheric pressure) after the cleaning processing and the rinse processing, it is possible to prevent liquidized additives from flowing into the processing chamber. As a result, such problems as a fine structure of an object being damaged by the liquidized additive and the object being wet can be prevented. Further, even in the case where another additive is added to the object using the same pipe in the subsequent processing, additives can be prevented from being mixed and hence an intended processing can be carried out.

Problems solved by technology

However, there still remains a problem that an additive dissolved into a supercritical fluid remaining in an end pipe is liquidized in the reduced-pressure state after the wafer is cleaned, entered into the substrate cleaning bath to wet the wafer and as a result the fine structure may be damaged.

Further, since the semiconductor wafer is cleaned and rinsed with the supercritical fluid under an extremely high pressure, it is difficult to purge the remaining additives from the end pipe in the rinsing process.

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