초록 |
We report on characteristics of amorphous indium zinc tin oxide (a-IZTO) electrode co-sputtered by linear facing target sputtering (LFTS) using ITO and IZO targets for bulk heterojunction organic solar cells (OSCs). Without substrate heating or post annealing, the a-IZTO electrode exhibited a low sheet resistance of 17.48 ohm/square, an high average optical transmittance of 88.1 % in 500 nm wavelength and work function of 5.22 eV. In addition, a-IZTO electrode shows much smoother surface with root mean square (RMS) roughness of 0.35 nm than a crystalline ITO electrode (RMS roughness of 1.25 nm), due to absence of bombardment of energetic particles on the IZTO electrode during co-sputtering process. Moreover, the OSC with the a-IZTO anode showed comparable open circuit voltage (0.56 V), short circuit current (9.16 mA/cm2), fill factor (68.1 %) and power conversion efficiency (3.5 %) to a OSC with a commercial crystalline ITO electrode. This indicates that LFTS grown a-IZTO electrode is a visible alternative to crystalline ITO electrode for low cost OSCs, eliminating annealing or substrate heating step for preparing high quality anode electrode. |