Development of diagnostic method of rapidly melting processes at crystalline silicon surface heated with femtosecond laser pulses

Abstract

Time resolved spectral reflectivity of the crystalline silicon surface irradiated with femtosecond laser pulses was observed with ultra short super continuum pulses with varying delay. The heated area of the solid silicon shows entirely different reflectivity spectrum from the crystalline, liquid, or amorphous state, suggesting un-identified novel state before reaching the thermal equilibrium.