Laser deposition of thin SiO2 and ITO ®lms

Multicomponent ®lms like ITO (indium tin oxide) and silica (SiO2) can be ef®ciently deposited by using the reactive pulsed laser deposition (RPLD) technique. We ablated Si, SiO and ITO targets in low-pressure O2 (0.1±5 Pa) with XeCl and KrF laser pulses at ¯uences of 5±8 J/cm2. The ®lms were deposited on Sih1 00i substrates at temperatures of 20±6008C. The substrate was generally set parallel to the target. To reduce droplet deposition, some ®lms were deposited in off-axis con®guration or using the so-called ``eclipse methodʹʹ, characterized by a shadow mask between target and substrate. Dense, continuous ITO ®lms with resistivity as low as 1:6 10ÿ4 O cm and a high transparency in the visible region were deposited. Ultra-thin ( 6 nm) ®lms were successfully used as electrodes in optoelectronic devices. Dense, stoichiometric, thick (>2 mm) SiO2 ®lms were deposited on substrates at room temperature. Droplet density and surface roughness are kept quite low ( 5 nm). # 2000 Elsevier Science B.V. All rights reserved