Abstract
The nucleation and growth of local molten regions (LMRs) during the light irradiation was detected using high-speed camera and long-focus microscope. In situ dependences of sizes and density (quantity per cm-2) of LMRs are interpreted in the frame of the following model. A great amount of heat is transferred to the semiconductor surface during light pulse irradiation. This proces is nonstationary and the heat is not distributed homogeneously over the thickness of the sample. As a result, a specific short-lived state is formed, in which the semiconductor surface is superheated in the solid-state phase with respect to the equilibrium melting temperature. Some surface areas, which contain the defects, begin to melt. Temperature of these local molten regions immediately decreases down to the equilibrium melting temperature. The created LMRs begin to absorb the heat from neighboring superheated solid regions. As a result, the temperature of superheated regions decreases down to the equilibrium melting point. No new local molten regions are formed and the sizes of existing local molten regions increase due to absorption of the energy of light pulse. To study the main features of local melting more detail in-situ investigations of mechanism of this effect were carried out at incoherent light irradiation with different pulse durations and irradiation power densities. The last our results agree with the superheating model. Also the dynamics of phase transitions on the surface of implanted silicon at different regimes of light pulses is investigated using high-speed camera and special diffraction gratings. The diffraction gratings were formed using ion implantation and the effect of local melting. The dynamics of diffraction during and after the light pulse irradiation was studied.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
