Precision cleaning apparatus and method

A cleaning monitor for determining an effectiveness of precision cleaning of an accumulation of at least one contaminant from a surface of a workpiece in contact with a cleaning medium within a cleaning zone comprising:

• (a) a sensor insertable into the cleaning zone and having at least one exposed side thereof for accumulation prior to insertion of the sensor into the cleaning zone of a layer of the contaminant substantially equal to the accumulation on the workpiece;
• and
• (b) measurement means connectable to the sensor for measuring at least one electrical response characteristic thereof that varies in response to removal of the layer of contaminants from the exposed side of the sensor by contact with the cleaning medium.

Apparatus for precision cleaning of an accumulation of a contaminant from a surface of a workpiece during contact with a cleaning medium, the apparatus comprising:

• (a) a cleaning container having walls which define a cleaning zone wherein the workpiece is contacted by the cleaning medium for removal of the contaminant therefrom;
• and
• (b) a cleaning monitor comprising an acoustic-wave sensor insertable into the cleaning zone with at least one exposed side thereof for accumulating prior to insertion of the sensor into the cleaning zone a layer of the contaminant thereon substantially equal to the accumulation on the workpiece, and measurement means connectable to the sensor for measuring at least one electrical response characteristic thereof that varies in response to removal of the layer of contaminant therefrom by contact with the cleaning medium.

Apparatus for precision cleaning of a contaminant from a workpiece comprising:

• (a) means for contacting the workpiece with a cleaning medium;
• and
• (b) means for measuring removal of an accumulated layer of the contaminant from a sensor to provide an indication of removal of the contaminant from the workpiece.

Apparatus for precision cleaning of a contaminant from a workpiece comprising:

• (a) a container having a cleaning zone wherein the workpiece is in contact with a cleaning medium;
• and
• (b) a sensor located in the cleaning zone and in contact with the cleaning medium, the sensor being responsive to removal of a layer of the contaminant accumulated thereon to sense removal of the contaminant from the workpiece.