INFRARED FOURIER SPECTROSCOPY OF DIFFUSE REFLECTIONOF THE AZ nLOF SERIES NEGATIVE PHOTORESISTS FILMSON MONOCRYSTALLINE SILICON

Films of the AZ nLOF 2020, AZ nLOF 2070 and AZ nLOF 5510 negative photoresists (PR) with a thickness of 0,95 – 6,1 μm, deposited on the surface of silicon wafers by the centrifugation method, were studied by the method of IR-Fourier diffuse reflection spectroscopy. In the diffuse reflectance spectra of PR/silicon structures, absorption bands were observed against the background of interference fringes. It allows the technique to be used to measure film thickness or its refractive index. The most intense bands in the AZ nLOF series PR spectra are the bands of stretching vibrations of the aromatic ring, pulsation vibrations of the carbon skeleton of the aromatic ring, a wide structured band with several maxima in the range of 1050 – 1270 cm–1 and a band associated with the CH2 bridge. The structure of the absorption spectrum of photoresists of the AZ nLOF series is similar to the structure of the spectrum of phenol-formaldehyde photoresist FP9120. It was shown that the vibration band of CH3 groups at 2945 cm-1 is due to the solvent.