Thresholds of Etchable Track Formation and Chemical Damage Parameters in PI, PET, PC, and PADC Films at the Stopping Powers Ranging from 10 to 12,000 keV/um

The damage structure of latent tracks in Polyimide (PI) films, KAPTON and UPILEX, has been examined by Fourier transform infrared (FT-IR) measurements. Results are compared with those from previous studies on poly(ethylene terephthalate) (PET), bisphenol A polycarbonate (PC), and poly(allyl diglycol carbonate) (PADC). These polymers are exposed to protons and heavy ions (He, C, Ne, Si, Ar, Fe, Kr, and Xe ) in air with energies less than 6 MeV/n, as well as gamma rays from an intense Co-60 source [1-5]. Chemical damage parameters, namely, damage density, which is the number of losses of considered functional groups per unit length of tracks, radial size of the track core, in which the considered chemical groups are lost, and radiation chemical yields (G values) for each group are evaluated as a function of the stopping power. It has been confirmed that latent tracks will be etchable when the radial track core size is larger than the distance between two adjacent breaking points of polymer chains. The predominant breaking points are the C-O bonds in diphenyl ether, ester, carbonate ester, and ether bonds.8ｔｈ International Symposium on Swift Heavy Ions in Mate