Development and characterization of multifunctional PassDop layers for local p+-laser doping

• Published in: Energy procedia Vol. 124; pp. 891 - 900
• Main Authors: Norouzi, Mohammad H., Saint-Cast, Pierre, Lohmüller, Elmar, Steinhauser, Bernd, Benick, Jan, Werner, Sabrina, Bitnar, Bernd, Palinginis, Phedon, Neuhaus, Holger, Hofmann, Marc, Wolf, Andreas
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2017
• Subjects: boron; laser doping; p-type solar cells; PassDop; passivation; PERL; recombination; screen printing; recombination; PassDop; passivation; PERL; laser doping; boron; p-type solar cells; screen printing
• ISSN: 1876-6102; 1876-6102
• DOI: 10.1016/j.egypro.2017.09.278

We present the development of aluminum oxide (AlOx) and boron-doped silicon nitride (SiNx:B) layer stacks for application on the back side of monocrystalline p-type silicon wafers. Two deposition techniques are used for the deposition of the AlOx/SiNx:B layer stacks, atomic layer deposition and plasma-enhanced chemical vapor deposition. Both techniques enable excellent surface passivation with surface recombination velocities of 4 cm/s after firing. Also, heavy local doping with sheet resistances down to 20 Ω/sq is possible by laser processing. We call this concept the PassDop approach. For the laser processed area where the silicon surface is locally boron-doped and the AlOx/SiNx:B passivation layer stack is locally removed, a quite low dark saturation current density of about 900 fA/cm2 is determined. The PassDop approach can be a solution to realize passivated emitter and rear locally doped PERL solar cells by improving their rear side properties while maintaining industrial applicability.