By Melbourne Centre for Nanofabrication
Laser Doppler Vibrometry (LDV) is used to measure the high frequency vibrations of surfaces by exploiting the Doppler shift in reflected laser light. This Doppler shifted light provides information on the velocity, displacement, and phase of the surface vibrations. LDV is useful in the characterisation of MEMS devices, as well as piezoelectrics and surface acoustic wave devices. MCN has two Polytec LDVs - the MSA-400 and UHF-120. The MSA-400 features a fully integrated system, combining a microscope with scanning laser doppler vibrometry and stroboscopic video microscopy for planar motion analysis. This all-in-one combination of technologies clarifies the real microstructural response of an oscillating system. Utilised in the MEMS device design cycle, the MSA-400 provides precise 3D dynamic and static response data that simplifies troubleshooting, enhances and shortens design cycles, improves yield and performance, and reduces product cost. The UHF-120 has a much larger bandwidth allowing for characterisation of samples with a 1µm diameter at ultra-high frequencies of up to 1.2 GHz. This tool is equipped with a motorised stage and is not equipped with the stroboscopic or planar motion analysis option.
