AVS 52nd International Symposium
    Thin Films Monday Sessions
       Session TF-MoP

Paper TF-MoP29
Film Properties of Transparent Conductive Oxide Films Deposited from Either ZnO- In@sub2@O@sub 3@or ZnO-SnO@sub2@ Systems with Additional Ga@sub2@O@sub3@ Impurities

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Aspects of Thin Films Poster Session
Presenter: K. Tominaga, Tokushima University, Japan
Authors: K. Tominaga, Tokushima University, Japan
D. Takada, Tokushima University, Japan
Y. Sukeda, Tokushima University, Japan
Y. Nishimura, Tokushima University, Japan
T. Moriga, Tokushima University, Japan
I. Nakabayashi, Tokushima University, Japan
Correspondent: Click to Email
Recently transparent conductive oxide films with smooth surface are expected. Lower deposition temperature is also expected for the TCO in polycarbonate substrate. For these applications, amorphous transparent conductive films are expected to be one of adequate materials. Amorphous films can be deposited in the system of ZnO-In@sub 2@O@sub 3@, or ZnO-SnO@sub 2@. Therefore we deposited those films, and investigated the influence of the incorporation of Ga@sub 2@O@sub 3@ on the film properties for those systems. Transparent conductive oxide films deposited from either ZnO-In@sub 2@O@sub 3@ or ZnO-SnO@sub2@ systems with additional Ga@sub2@O@sub3@ impurities were deposited by facing target sputtering system. ZnO:Ga and In@sub2@O@sub3@ targets were used for ZnO-In @sub2@O@sub 3@ films, and ZnO:Ga and In@sub2@O@sub3@ for ZnO-SnO@sub 2@ films. Two targets were sputtered simultaneously in Ar gas at 1 mTorr, and electric current ratio @deruta@=I@sub Zn@/(I@sub Zn@+I@sub In@) or I@sub Zn@/(I@sub Zn@+I@sub Sn@) was adopted as a deposition parameter to change film composition. Discharge current of each target was changed from 0 to 80 mA in order to change the content ratio of Zn/(In+Zn) or Zn/(Sn +Zn) in the film. Compositional ratios in films were estimated by X-ray fluorescence analysis. We could deposit ZnO-In@sub 2@O@sub 3@ amorphous films between Zn/(Zn+In)=0.2-0.5 even at a temperature of 250 °C. Low resistivity of the order of 10@super -4@@ohm@cm was attained in amorphous phase. Optical transparency was good for all films. For the amorphous films, optical bandgap energy shifted to higher energy side with decreasing the resistivity. Homologous films were deposited between Zn/(Zn+In)=0.5-0.75. These films had higher resistivity and larger optical bandgap than those of amorphous films. Similar results were obtained for SnO@sub 2@:Sb and ZnO:Ga, although the film resistivities were higher than ZnO-In @sub2@O@sub 3@.