Internal profile reconstruction for MEMS microstructures based on infrared transmission technology

The measurement system based on white light interference technology is proposed for the internal profile measurement of standard GaAs step micro structures. It is extended from white light interference measurement to the infrared light transmission interference measurement. Comparing with measurement results in reflection interference and infrared transmission interference experiments, the whole system including algorithm is feasible for the resolution of internal profile of micro structures. Measurement resolution can reach micron level on lateral and nanometer on axial direction. The system, which can basically realize the transmission measurement of micro structures, has the potential application in the sidewall and bottom profile measurement of micro structures with high aspect ratio.