Silicon wafers are processed by the addition of dielectric films that are used primarily to isolate circuits from each other and to provide mechanical and chemical protection to the device itself. They are also used as masking materials during the wafer fabrication process. There are a variety of different film substrates, two of the common ones being borophosphosilicate glass and silicon nitride.
FTIR (Fourier transform infrared) spectroscopy is used widely within the electronics and solar industries for the determination of the chemical properties of materials. This application note describes the FTIR method for the measurement and calculation of the -NH and -SiH content in silicon nitride films.