Novel test structures for characterization of microsystems parameters at wafer level

This work deals with in-line measurement techniques for quantification of important microsystems parameters and related scattering caused by the process conditions. Material properties, mechanical stress but also geometrical dimensions and their tolerances are characterized by indirect method, based on specially designed test-structures. This method involves a data fusion process that combines numerically calculated and experimentally determined information to estimate sought parameters. Laser Doppler Vibrometrie is used to determine the frequency response function (FRF) of the test-structure and find out their Eigenfrequencies. For the numerical simulation of the test-structures a parametrical finite element (FE) model is used and a series of pre-stressed modal analyses have been performed. Hence the dependence of the Eigenfrequencies on parameters of interest is obtained. The comparison to the measured frequencies yields the values of the desired parameters. The test-structures are designed, produced and used for microsystems manufacturing monitoring in Bonding and Deep Reactive Ion Etching (BDRIE) processes. An optimization of the teststructures' form for a nontrivial goal function is shown. Measurement results of the presented technique are comparable with results of common characterization methods. The presented technique is both in-situ and non-destructive.