Surface modification of titanium nitride film by a picosecond Nd : YAG laser

摘要

The interaction of a picosecond Nd: YAG laser ( wavelength 532 nm, pulse duration 40 ps) with a polycrystalline titanium nitride ( TiN) film was studied. The TiN thin film was deposited by physical vapour deposition on a silicon substrate. The titanium nitride/ silicon system was modified with an energy fluence from 0.2 to 5.9 J cm(-2). Multi- pulse irradiation was performed in air by a focused laser beam. Surface modifications were analysed after 1 - 100 successive laser pulses. Depending on the laser pulse energy and pulse count, the following phenomena were observed: ( i) increased surface roughness, ( ii) titanium nitride film cracking, ( iii) silicon substrate modification, ( iv) film exfoliation and ( v) laser- induced periodical surface structures on nano- ( NPSS) and micro- dimensions ( MPSS).