Patent ID: 7629726

Claim:
A megasonic system for coupling megasonics to a liquid, comprising: a megasonic transducer assembly having a first piezoelectric ceramic bonded to a second piezoelectric ceramic; a megasonic generator having a phase shift network and an electronic bridge circuit configured to selectively produce at least a first megasonic frequency of operation and a second megasonic frequency of operation and to selectively produce a driver signal characterized by a first megasonic frequency within a first megasonic frequency band and to selectively produce a second megasonic frequency within a second megasonic frequency band that is different from and non-contiguous to said first megasonic frequency band; said bridge circuit and phase shift network configured to provide an output voltage and an output current, wherein said output voltage leads said output current by an angle that is greater than 0 degrees and less than about ninety degrees into said phase shift network; said phase shift network having a non-resistive output circuit having a Norton equivalent impedance near infinity at said first frequency of operation; a transmission line connecting said transducer assembly to said megasonic generator; at least one parallel inductor matching network between said transmission line and said transducer assembly; at least one sensor adapted to sense operating conditions of said megasonic system; a processor communicating with said sensor; non-volatile memory coupled to said processor; and said processor programmed to receive a signal from said sensor during operation of said megasonic system and to store said signal in said memory for access after operation of said megasonic system when said signal indicates a system error, fault or failure.