平均光穿透率84％。經真空退火後皆可以在波長400nm 至1100nm 得到80％以上的平均光穿
For evaluating the possibility to improve the electrical and optical properties on aluminum
doped zinc oxide (AZO) films with annealing, a series of low pressure annealing on AZO films
prepared by in line direct circuit sputtering was made.
Vacuum annealing was treated with 300℃, 400℃and 500℃ temperature. The results indicate
vacuum annealing can improve the electrical resistivity from the order of 10-3 to 10-4 ohm-cm for
AZO films produced with substrate no extra heating. The average optical transmittance between
400 and 1100 nm wavelength region can be more than 80% for all AZO films prepared with
different substrate heating temperatures and process gas after vacuum annealing. The X-ray
diffraction results show interesting behavior. There is apparent (002) preferential crystal direction
appeared for all AZO films with and without annealing. Instead of increase, the (002) X-ray
diffraction peak intensity decreases, and peak shape becomes asymmetry for 150℃ substrate
heating temperature after annealing. The (002) X-ray diffraction peak intensity increases and peak
shape becomes symmetry for 200℃ substrate heating temperature after annealing. These
phenomena are attributed to that annealing induces stress relaxation inside AZO films and interface
between films and substrate, but the interface stress is transferred to films not completely relaxed
for 150℃ substrate heating temperature after annealing. For higher substrate temperature like
200℃, interface stress has been relaxed to some extent during film deposition. The film stress
relaxes almost completely after annealing.
This work contributes the possible choice to use low pressure annealing to improve electrical
and optical properties of AZO films prepared by industry producing method : in line sputtering.