Two-dimensional low-coherence interferometry for the characterization of nanometer wafer topographies

摘要: Within this work a scan-free, low-coherence interferometry approach for surface profilometry with nm-precision is presented. The basic setup consist of Michelson-type interferometer which powered by super-continuum light-source (Δλ= 400-1700 nm). introduction an element known dispersion delivers controlled phase variation can be detected in the spectral domain and used to reconstruct height differences on sample. In order enable scan-free measurements, interference signal spectrally decomposed grating imaged onto two-dimensional detector. One dimension detector records spectral, therefore information, while other stores spatial position corresponding values. experiments standard, it could shown that capable recording multiple steps 101 nm over range 500 m accuracy about 11.5 nm. Further conductive paths micro-electro-mechanical systems (MEMS) pressure sensor demonstrated also suitable precisely characterize nanometer-sized structures production-relevant components. main advantage proposed measurement possibility collect precise information line without need scanning. This feature makes interesting production-accompanying metrology.