Properties of boron doped ZnO films prepared by reactive sputtering method: Application to amorphous silicon thin film solar cells

Reactive sputtered boron-doped zinc oxide (BZO) film was deposited from argon, hydrogen and boron gas mixture. The reactive sputtering technique provides us the flexibility of changing the boron concentration in the produced films by using the same intrinsic zinc oxide target. Textured surface was obtained in the as-deposited films. The surface morphology and the opto-electronic properties of the films can be controlled by simply varying the gas concentration ratio. By varying the gas concentration ratio, the best obtained resistivity ∼ 6.51 × 10−4 Ω-cm, mobility ∼ 19.05 cm2 V-1 s-1 and sheet resistance ∼ 7.23 Ω/□ were obtained. At lower wavelength of light, the response of the deposited films improves with the increase of boron in the gas mixture and the overall transmission in the wavelength region 350−1100 nm of all the films are >85 %. We also fabricated amorphous silicon (a-Si) thin film solar cell on the best obtained BZO layers. The overall efficiency of the a-Si solar cell is 8.14 %, found on optimized BZO layer.