Femtosecond Pulsed Laser Deposition of Indium on Si (100)

Deposition of indium on Si(100) substrates is performed under ultrahigh vacuum with an amplified Ti:sapphire laser (130 fs) at wavelength of 800 nm and laser fluence of 0.5 J/cm. Indium films are grown at room temperature and at higher substrate temperatures with a deposition rate of ~ 0.05 ML/pulse. Reflection high-energy electron diffraction (RHEED) is used during the deposition to study the growth dynamics and the surface structure of the grown films. The morphology of the grown films is examined by ex situ atomic force microscopy (AFM). At room temperature indium is found to form epitaxial two-dimensional layers on the Si(100)-(2×1) surface followed by threedimensional islands. AFM images show different indium island morphologies such as hexagonal and elongated shapes. At substrate temperatures of 400-420 C, RHEED intensity oscillations are observed during film growth indicating that the indium film grows in the layer-by-layer mode.