Fig. 1.

Image frames obtained by using fs and ns pulses. Frames 1–5 show the growth of crystallite size as the number of fs pulses increases, with the transition from amorphous (1) to polycrystalline (5) being evident in the images. The central colored image shows the response after a single laser-pulse heating. The zones are identified by circles to indicate the amorphous (a), the interfacial (i), and the two crystalline (c and C) phases. The C-zone diameter is 35 μm and the c-zone diameter is 77 μm (see text). The specimen in the microscope was thin films of amorphous silicon deposited on a grid by e-beam evaporation of a silicon wafer (also see Fig. 2).