| Title |
Influences of Plasma Treatment on the Electrical Characteristics of rf-magnefrom sputtered BaTa_2O_6 Thin Films |
| Authors |
김영식(Kim, Young-Sik) ; 이윤희(Lee, Yun-Hi) ; 주병권(Ju, Byeong-Kwon) ; 성만영(Sung, Mang-Young) ; 오명환(Oh, Myung-Hwan) |
| Keywords |
BaTa_2O_6 thin films ; ACTFELD ; Oxygen Plasma treatment ; High dielectric donstant |
| Abstract |
Direct current(d.c.)leakage current voltage characteristics of radio-frequencymagnetron sputtered BaTa sub 2 O sub 6 film capacitors with aluminum(A1) top and indium tin oxide (ITO) bottom electrodes have been investigatedas a function of applied field and temperature. In order to study surfacetreatment effect on the electrical characteristics of as-deposited film weperformed exposure of oxygen plasma on BaTa_2O_6 surface. d. c.current-voltage (I-V), bipolar pulse charge-voltage (Q-V), d. c. current-time (I-t) andcapacitance-frequency (C-f) analysis were performed on films. All ofthe films exhibita low leakage current, a high breakdown field strength (3MV/cm-4.5MV/cm), and high dielectric constant (20-30). From the temperature dependence of leakage current,we can conclude that the dominant conduction mechanism is ascribed toSchottky emission at high electric field (>1MV/cm) and hopping conduction at lowelectric field (<1MV/cm). According to our results, the oxide plasma surfacetreatmenton as-deposited BaTa_2O_6 resulted in lowering interfacebarrier height and thus, leakage current when a negative voltage applied to the A1 electrode. This can be explained by reduction of surface contamination via etching surface and filling defects such as oxygen vacancies. |