Transparent and crystalline Al-doped ZnO film-embedded heterojunction Si solar cell

A heterojunction of Al-doped ZnO (AZO) and Si was applied as a solar cell. Quality AZO films were grown by a co-sputtering technique using a RF power supply for ZnO while a DC one for Al. The Al content significantly modulates the electrical performance and crystalline structure of the AZO films. The lowest resistivity of AZO film was achieved to be 5.4 × 10 ^-4 ωcm. The crystalline structures of different Al-containing AZO films were systematically investigated by X-ray diffraction. A transparent AZO film was deposited onto an n-Si substrate. This AZO/Si heterojunction diode offers an ideality factor of 1.19. Under illumination, the heterojunction provided a short-circuit current of 15.64 mA/cm ² and an open-circuit voltage of 321 mV. This research presents the quality growth of AZO films by using a co-sputtering method. It also discusses the working mechanism of the heterojunction n-AZO/n-Si solar cells with unique design schemes.