Polymer thermal protection induced by ion beam irradiation

The thermal stability of F, Ne, He, and B implanted/irradiated AZ1350-J photoresist films has been investigated via the Rutherford backscattering (RES) technique. We find that both shallow and deep implantations raise the temperature at which the photoresist starts to decompose (from 400 degrees C to 450 degrees C). It is shown that radiation rather than chemical effects are responsible for the improvement in the thermal behavior of the implanted/irradiated films. In addition it is observed that the deep implantations give better results as compared with the shallow ones. In fact after a high energy Ne, B or He irradiation fluence was reached, no material loss was observed when the samples were further submitted to 450 degrees C annealings. This is at variance with what was observed with shallow F and Ne implantations, where only partial protection was achieved. (C) 1998 Elsevier Science B.V.