Study on the ITO work function and hole injection barrier at the interface of ITO/a-Si:H(p) in amorphous/crystalline silicon heterojunction solar cells

Abstract For this study we focused on the front contact barrier height of HIT (ITO/a-Si:H(p)/a-Si:H(i)/c-Si(n)) solar cell. The ITO films with low resistivity of 1.425 × 10−4 Ω cm were deposited by pulsed DC magnetron sputtering as a function of substrate temperature (Ts). There were improvement in ΦITO from 4.15 to 4.30 eV and delta hole injection barrier from 0 to 0.129 eV for the HIT solar cell. The results show that the high values of ΦITO and the delta hole injection barrier at the front interface of ITO/p-layer lead to an increase of open circuit voltage (Voc), fill factor (FF) and efficiency (η). The performance of HIT device was improved with the increase of Ts and the best photo voltage parameters of the device were found to be Voc = 635 mV, FF = 0.737 and η = 14.33% for Ts = 200 °C.