Ultrasonic cleaning method and apparatus therefore

An apparatus, comprising:

• a substantially circular tank comprising a top portion, a bottom portion, and a sidewall disposed therebetween, the tank being configured to contain a cleaning fluid and to receive a plasma processing chamber window submerged in the cleaning fluid;
• a plurality of cleaning fluid inlets selected from nozzle injectors, fan injectors, and combinations thereof, each cleaning fluid inlet at least partially disposed in the sidewall proximate to the bottom portion of the tank and configured to deliver the cleaning fluid to the tank;
• an intermediate support for receiving a plasma processing chamber window, the intermediate support configured to maintain the window in the tank above the plurality of cleaning fluid inlets and below a plurality of fluid outlet ports disposed in the sidewall proximate to the top portion of the tank;
• an ultrasonic generator coupled to the tank for generating ultrasonic waves in the tank and the cleaning fluid received therein;
• wherein the intermediate support comprises an upper support surface and a base structure opposite the upper support surface, and is configured to define (i) a substantially continuous outer circumferential fluid gap between a substantial entirety of an outer circumference of the intermediate support and an inner circumference of the tank;
• (ii) a substantially discontinuous inner circumferential fluid gap between an intermediate circumference of the intermediate support and the window supported by the upper support surface of the intermediate support;
• and (iii) a plurality of radial cleaning fluid passages extending through the base structure of the intermediate support from the outer circumference of the intermediate support to an inner circumference of the intermediate support;
• and
• wherein the apparatus is configured to receive the window such that a plasma-facing surface of the window is oriented to face the bottom portion of the tank, to receive the cleaning fluid from the cleaning fluid inlets, remove particles from the window, and direct flow of the cleaning fluid such that removed particles are carried away from the window and out of the tank through the fluid outlet ports.

A method of cleaning a substantially planar article, comprising:

• providing a substantially circular tank comprising (i) a top portion, (ii) a bottom portion, and (iii) a sidewall disposed therebetween, the tank being configured to contain a cleaning fluid and to receive a substantially planar article submerged in the cleaning fluid;
• (iv) a plurality of cleaning fluid inlets at least partially disposed in the sidewall proximate to the bottom portion of the tank;
• (v) a plurality of fluid outlet ports disposed in the sidewall proximate to the top portion of the tank;
• (vi) an intermediate support for receiving a substantially planar article, the support comprising an upper support surface, a base structure opposite the upper support surface, and a plurality of radial cleaning fluid passages extending through the base structure from an outer circumference of the support to an inner circumference of the support;
• and (vii) an ultrasonic generator coupled to the tank for generating ultrasonic waves in the tank and the cleaning fluid received therein;
• introducing a substantially planar article to be cleaned into the tank such that the article is received and maintained by the support above the plurality of cleaning fluid inlets and below the plurality of fluid outlet ports;
• introducing the cleaning fluid into the tank through the plurality of cleaning fluid inlets;
• exciting the cleaning fluid with ultrasonic waves;
• and
• allowing the cleaning fluid to flow out of the tank through the plurality of fluid outlet ports;
• wherein particles are removed from the substantially planar article and carried by flow of the cleaning fluid away from the article and out of the tank.