Mechanical properties of He irradiated and annealed AZ-1350 JTM films

The nanoindentation technique is used to measure hardness and Young's modulus in 1.7 μm thick photoresist AZ-1350JTM films deposited on Si wafer and irradiated with He ions at 380 keV and at fluences of 1013, 1014 and 1015 He cm-2. After irradiation the films have been also submitted to isothermal treatments at 350 deg. C for 6 h. The hardness value of 0.45 GPa for pristine film increases with ion irradiation to 2.3 GPa at the highest fluence. Thermal annealing, after irradiation, produces changes in the hardness behavior: for the lowest fluence the hardness raise from 0.7 to 1.0 GPa and for the highest fluence decreases from 2.3 to 1.8 GPa. The Young's modulus values also follow a similar variation after irradiation and thermal treatment. These results are discussed in terms of the crosslinking and the carbonization produced by irradiation and thermal treatment