| Title |
A Study on Electrical Properties of Ta_2O_{5-x} Thin-films Obtained by O_2 RTA |
| Authors |
김인성(Kim, In-Seong) ; 송재성(Song, Jae-Seong) ; 윤문수(Yun, Mun-Su) ; 박정후(Park, Jeong-Hu) |
| Keywords |
RTA oxidation ; Ta_2O_{5-x} ; MIM Capacitor ; thin films ; Electrical properties |
| Abstract |
Capacitor material utilized in the downsizing passive devices and integration of passive devices requires the physical and electrical properties at given area such as capacitor thickness reduction, relative dielectric constant increase, low leakage current and thermal stability. common capacitor materials, Al_2O_3, SiO_2, Si_3N_4, SiO_2/Si_3N_4, TaN and et al., used until recently have reached their physical limits in their application to integration of passive devices. Ta_2O_{5} is known to be a good alternative to the existing materials for the capacitor application because of its high dielectric constant (25~35), low leakage current and high breakdown strength. Despite the numerous investigations of Ta_2O_{5} material, there have little been established the clear understanding of the annealing effect on capacitance characteristic and conduction mechanism. This study presents the dielectric properties Ta_2O_{5} MIM capacitor structure Processed by O_2 RTA oxidation. X-ray diffraction patterns showed the existence of amorphous phase in 600°C annealing under the O_2 RTA and the formation of preferentially oriented-Ta_2O_{5} in 650, 700°C annealing and the AES depth profile showed O_2 RTA oxidation effect gives rise to the O_2 deficientd into the new layer. The leakage current density respectively, at 3~1l×10_{-2}(kV/cm) were 10_{-3}~10_{-6}(A/ textrm cm^2). In addition, behavior is stable irrespective of applied electric field. the frequency vs capacitance characteristic enhanced stability more then Ta_2O_{5} thin films obtained by O_2 reactive sputtering. The capacitance vs voltage measurement that, Vfb(flat-band voltage) was increase dependance on the O_2 RTA oxidation temperature. |