Photothermal displacement detection and transient imaging of bump growth dynamics in laser zone texturing of Ni-P disk substrates

A novel photothermal displacement method has been applied to probe the puls ed laser-induced feature formation of Ni-P hard disk substrates in the lase r zone texturing process. The deflection signals of the reflected probing b eam show the variation of the feature shape resulting from different pulse energies of the heating laser beam. A laser flash photography system is als o developed to visualize the feature growth dynamics. This system has nanos econd time resolution and about one micron spatial resolution. Both techniq ues show clearly the transient melting and deformation process and the time scale of such deformation. (C) 1999 American Institute of Physics. [S0021- 8979(99)32308-2].