Impact of the Oxygen Flow during the Magnetron Sputtering Deposition on the Indium Tin Oxide thin films for Silicon Heterojunction Solar Cell
Brahim Aïssa1, Yahya Zakaria1, Amir A. Abdallah1, Maulid M. Kivambe1, Ayman Samara1, Akshath Raghu Shetty1, Jean Cattin2, Jan Haschke2, Mathieu Boccard2, Christophe Ballif2
1Qatar Environment and Energy Research Institute, Hamad bin Khalifa University, Qatar Foundation, P.O. Box 34110, Doha, Qatar
/2Photovoltaics and Thin-Film Electronics Laboratory (PV-lab), Institute of Microengineering, Ecole Polytechnique Fédérale de Lausanne, Rue de la Maladière 71B, CH-2002 , Neuchatel, Switzerland

We report on the optoelectronic properties of ITO layers deposited by DC sputtering, using different oxygen to total flow ratios [r(O2) = O2/Ar, ranging from 1% to 8%], for silicon heterojunction (SHJ) solar cell application. The depth profiling of the various elements throughout the thicknesses and interfaces of the ITOs and thin films forming the SHJ device was determined by time-of-flight secondary ion mass spectrometry. Finally, the photovoltaic performance of the fabricated SHJ cells was evaluated with respect to the r(O2) into the ITO layers. Lower r(O2) was found to yield the best PV performance which is attributed to lower parasitic resistive losses.