TY - JOUR
T1 - Electrical, structural and optical characterization of copper oxide thin films as a function of post annealing temperature
AU - Fortunato, Elvira Maria Correia
AU - Martins, Rodrigo Ferrão de Paiva
PY - 2009/1/1
Y1 - 2009/1/1
N2 - Copper oxide thin films were obtained by annealing (temperature ranging between 100 and 450 degrees C) the metallic Cu films deposited on glass substrates by e-beam evaporation. XRD studies confirmed that the cubic Cu phase of the asdeposited films changes into single cubic Cu(2)O phase and single monoclinic CuO phase, depending on the annealing conditions. The crystallite size is varied between similar to 12 and 31 nm. The lattice parameters of cubic Cu and Cu(2)O phases are estimated to similar to 3.60 and similar to 4.26 angstrom, respectively. The films with Cu(2)O phase showed p-type characteristics. The conductivity is decreased linearly with the decreasing temperature (1/T), which has confirmed the semiconductor nature of the deposited films. The calculated activation energy is varied between 0.10 and 0.16 eV. The surface microstructure is changed depending on the variation in the annealing temperature. The poor transmittance of the asdeposited films (<1%) is increased to a maximum of similar to 80% (800 nm) on annealing at 200'degrees C. The estimated direct allowed band gap is varied between 1.73 and 2.89 eV.
AB - Copper oxide thin films were obtained by annealing (temperature ranging between 100 and 450 degrees C) the metallic Cu films deposited on glass substrates by e-beam evaporation. XRD studies confirmed that the cubic Cu phase of the asdeposited films changes into single cubic Cu(2)O phase and single monoclinic CuO phase, depending on the annealing conditions. The crystallite size is varied between similar to 12 and 31 nm. The lattice parameters of cubic Cu and Cu(2)O phases are estimated to similar to 3.60 and similar to 4.26 angstrom, respectively. The films with Cu(2)O phase showed p-type characteristics. The conductivity is decreased linearly with the decreasing temperature (1/T), which has confirmed the semiconductor nature of the deposited films. The calculated activation energy is varied between 0.10 and 0.16 eV. The surface microstructure is changed depending on the variation in the annealing temperature. The poor transmittance of the asdeposited films (<1%) is increased to a maximum of similar to 80% (800 nm) on annealing at 200'degrees C. The estimated direct allowed band gap is varied between 1.73 and 2.89 eV.
U2 - 10.1002/pssa.200881797
DO - 10.1002/pssa.200881797
M3 - Article
SN - 1862-6300
VL - 206
SP - 2143
EP - 2148
JO - PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
JF - PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
IS - SI9
ER -