Room temperature deposition of amorphous p-type CuFeO2 and fabrication of CuFeO2/n-Si heterojunction by RF sputtering method

Transparent conducting amorphous p-type CuFeO2 (CFO) thin film was prepared by radio-frequency (RF) magnetron sputtering method at room temperature using polycrystalline CuFeO2 target. Amorphous structure of as-deposited film was confirmed by XRD. XPS analysis convinced that the chemical state of Cu+ and Fe3+ in the film, and the chemical composition of the thin films is close to the stoichiometry of CuFeO2. Surface morphology of the film was analysed by SEM studies. p-type nature and concentration of carriers was investigated by Hall effect measurement. The p–n heterojunction in the structure of Al/n-Si/p-CuFeO2/Al showed good rectifying behaviour with a forward and reverse currents ratio of 555 at 2 V. The turn-on voltage and reverse leakage current values were found to be 0.9 V and 4 μA at −2 V. Further, the conduction mechanism of forward bias voltage was controlled by thermionic emission (TE) and trap-space charge limited current (TCLC) mechanisms.