Title :
Atomic-layer-deposited aluminum oxide for the surface passivation of high-efficiency silicon solar cells
Author :
Schmidt, Jan ; Merkle, Agnes ; Hoex, B. ; van de Sanden, M.C.M. ; Kessels, W.M.M. ; Brendel, Rolf
Author_Institution :
Institut fÿr Solarenergieforschung Hameln (ISFH), Am Ohrberg 1, 31860 Emmerthal, Germany
Abstract :
We present independently confirmed efficiencies above 20% for PERC-type solar cells with the point-contacted rear being either passivated by atomic-layer-deposited Al2O3 or by stacks consisting of an ultrathin Al2O3 film and a thicker PECVD-SiOx layer. Internal quantum efficiency measurements reveal that the effective rear surface recombination velocities of the single-layer Al2O3-passivated cells are comparable to those measured on reference cells passivated by an aluminum-annealed thermal SiO2, while those of the Al2O3/SiOx-passivated cells are even lower. Very low effective rear surface recombination velocities of only 70 cm/s are reported for the Al2O3/SiOx stacks, including metalized areas on the cell rear.
Keywords :
Aluminum oxide; Atomic layer deposition; Atomic measurements; Oxidation; Passivation; Photovoltaic cells; Plasma measurements; Plasma temperature; Silicon compounds; Velocity measurement;
Conference_Titel :
Photovoltaic Specialists Conference, 2008. PVSC '08. 33rd IEEE
Conference_Location :
San Diego, CA, USA
Print_ISBN :
978-1-4244-1640-0
Electronic_ISBN :
0160-8371
DOI :
10.1109/PVSC.2008.4922636