Low-temperature growth of low-resistivity indium-tin-oxide thin films by pulsed laser deposition

Properties of indium-tin-oxide (ITO) thin films grown on glass and silicon (Si) substrates from a 95 wt% In2O3-5wt% SnO2 sintered ceramic target by pulsed laser deposition (PLD) are compared and discussed. Depositions were performed under different oxygen pressures (PO2) ranging from 0.1-6.7 Pa and substrate temperature (T-s) from room temperature (RT) to 350 degreesC range. PO, was found to affect the properties of the ITO films. At RT under a PO, of 1.3 Pa, the resistivity of 4.5 x 10(-4) and of 4.8 x 10-4 Ohm cm were obtained on glass and Si substrates, respectively, while at 200 degreesC, the respective resistivity was reduced to 1.7 x 10(-4) and 1.6 x 10(-4) Ohm cm on glass and Si. No significant difference in the resistivity was observed in the films deposited on both substrates. High carrier density(similar to 10(21)cm(-3)) and Hall mobility (similar to 33cm(2)V(-1)s(-1)) were obtained at PO2 of 0.7-1.3 Pa at RT and 200 degreesC. For PO2 > 0.7 Pa, optical transmittance (visible light) above 80% was displayed by the films deposited on glass. XRD showed that at low T-s < 150<degrees>C, the films deposited on glass and Si were amorphous, while at T-s greater than or equal to 150 degreesC, crystalline films were obtained on both substrates. (C) 2000 Elsevier Science Ltd. All rights reserved.