Acquisition of modulated PZT signal and application of SEAM

PZT transducers can be used to measure the characteristics of materials irradiated by laser or electron beams. In order to maintain high measurement resolution, the signal aroused on the transducer is modulated to produce a modulated PZT signal. Signal acquisition is accomplished with a lock-in amplifier and computer technologies. A typical application is SEAM (Scanning Electrical Acoustic Microscopy). The SEAM image reflects the thermal characteristics of materials. Furthermore, the SEAM image can supply subsurface information without destroying the sample.