Electrical and optical properties of indium tin oxide thin films grown by pulsed laser deposition

Indium tin oxide (ITO) thin films (200-400 nm in thickness) have been grown by pulsed laser deposition (PLD) on glass substrates without a post-deposition anneal. The electrical and optical properties of these films have been investigated as a function of substrate temperature and oxygen partial pressure during deposition. Films were deposited at substrate temperatures ranging from room temperature to 300 degrees C in O-2 partial pressures ranging from 0.1 to 100 mTorr. For 300 nm thick ITO films grown at room temperature in oxygen pressure of 10 mTorr, the electrical conductivity was 2.6 x 10(-3) Omega(-1) cm(-1) and the average optical transmittance was 83% in the visible range (400-700 nm). For 300 nm thick ITO films deposited at 300 degrees C in 10 mTorr of oxygen, the conductivity was 5.2 x 10(-3) Omega(-1) cm(-1) and the average transmittance in the visible range was 87%. Atomic force microscopy (AFM) measurements showed that the RMS surface roughness for the ITO films grown at room temperature was similar to 7 Angstrom, which is the lowest reported value for the ITO films grown by any film growth technique at room temperature.