Determination of electrical parameters of ZnO/Si heterojunction device fabricated by RF magnetron sputtering

Abstract

In the present study, the electrical parameters of the ZnO/Si heterojunction device fabricated via RF magnetron sputtering are examined in detail and the results are compared with literature. Structural and morphological analyses have been done to understand and expound device behavior and results of electrical studies. XRD analysis confirms the crystal formation of ZnO phase with (103) and (111) oriented, while AFM analysis shows that the film surface is homogeneous and the mean roughness is approximately as 2nm. The carrier concentration and conductivity type of ZnO thin film were obtained by Hall Effect measurement as 5.56x10(17)cm(-3), n-type, respectively. The dark current-voltage and capacitance-voltage measurements were carried out to obtain the electrical parameters of the device. From the dark current-voltage measurement the ideality factor, barrier height, and series resistance were estimated as n=2.16, phi(b)=0.71eV, and R-s=92.5. The barrier height was also obtained by the capacitance-voltage measurement handled at room temperature. The results were compared with those obtained from similar or different production methods. Illumination current-voltage measurement was also performed to determine if the fabricated heterojunction device has photovoltaic properties.