SpectrEcology

When measuring the thickness of substrates such as silicon wafers or optical layers, consider our Silicon-Silicon Dioxide (Si-SiO2) Reference Wafer. This is a 9.8-cm diameter, 6-step wafer that has a calibrated thickness range of 0-350 nm, and is ideal for use as a reference standard when measuring the thickness of thin, transparent layers on different substrates. The Reference Wafer consists of a thin wafer of silicon dioxide on silicon, with each transparent step numbered and etched on  the wafer surface. A calibration data sheet -- the wafer is calibrated using an ellipsometer -- includes for each step information such as the X and Y positions, psi, gamma, period (in mm) and thickness (in mm).