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

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 x 10(-4) Omega cm were deposited by pulsed DC magnetron sputtering as a function of substrate temperature (T-s). There were improvement in Phi(ITO) 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 Phi(ITO) and the delta hole injection barrier at the front interface of ITO/p-layer lead to an increase of open circuit voltage (V-oc), fill factor (FF) and efficiency (eta). The performance of HIT device was improved with the increase of T-s and the best photo voltage parameters of the device were found to be V-oc = 635 mV, FF = 0.737 and eta = 14.33% for T-s = 200 degrees C. (C) 2012 Elsevier Ltd. All rights reserved.