REACTION STUDIES BETWEEN FLUOROCARBON FILMS AND SI USING TEMPERATURE-PROGRAMMED X-RAY PHOTOELECTRON AND DESORPTION SPECTROSCOPIES

Surface structure of plasma-polymerized fluorocarbon thin film on Si a nd gas desorption were concurrently studied as a function of temperatu re between 20 and 700 degrees C using temperature-programmed X-ray pho toelectron spectroscopy with a residual gas analyzer. The films, consi sting of CF3, CF2, CF and C-CFx bonds, with the F/C ratio of 1.7 were found to be stable up to 200 degrees C and to thermally decompose abov e 200 degrees C. SiF4 desorption, following gradual pyrolysis with dec rease in CF3, CF2 and CF bonds due to desorption of fluorocarbon gases , was observed for F/C ratios ranging from 1 to 0.1. The pyrolytic pro cess of the film and the thermal reaction with Si substrates were furt her discussed based on results of additional desorption and ion-induce d reaction experiments.