| abstract |
A precision cleaning apparatus and method. The precision cleaning apparatus includes a cleaning monitor further comprising an acoustic wave cleaning sensor such as a quartz crystal microbalance (QCM), a flexural plate wave (FPW) sensor, a shear horizontal acoustic plate mode (SH-APM) sensor, or a shear horizontal surface acoustic wave (SH-SAW) sensor; and measurement means connectable to the sensor for measuring in-situ one or more electrical response characteristics that vary in response to removal of one or more contaminants from the sensor and a workpiece located adjacent to the sensor during cleaning. Methods are disclosed for precision cleaning of one or more contaminants from a surface of the workpiece by means of the cleaning monitor that determines a state of cleanliness and any residual contamination that may be present after cleaning; and also for determining an effectiveness of a cleaning medium for removing one or more contaminants from a workpiece. |