LASER-INDUCED PHOTODEPOSITION OF GOLD UPON P-SILICON IMMERSED IN CHLOROAURIC ACID-SOLUTIONS

Gold deposits on p-silicon substrates from chloroauric acid solutions have been obtained by the electroless photochemical deposition techniq ue. A low-power incident laser beam (1 mW) was used with the intention of preventing the thermal decomposition of the precursor compound in the solution or pyrolytic effects at the substrate surface. Deposited spots of gold dots had diameters of 25-100 mum. The dots writing perio ds were in the range of 1-3 min. The surface morphology of the deposit s was observed by SEM (scanning electron microscopy) and AFM (atomic f orce microscopy). The deposited patterns obtained at room temperature consist of columnar structures with characteristic grain dimensions of the order of 0.3-1.5 mum. Single-crystalline fcc-gold structures were observed for longer exposure times in the range 15-20 min.