Title :
Electrical and Structural Analysis of Crystal Defects After High-Temperature Rapid Thermal Annealing of Highly Boron Ion-Implanted Emitters
Author :
Krügener, Jan ; Peibst, Robby ; Wolf, F. Alexander ; Bugiel, Eberhard ; Ohrdes, Tobias ; Kiefer, Fabian ; Schollhorn, Claus ; Grohe, Andreas ; Brendel, Rolf ; Osten, H. Jorg
Author_Institution :
Inst. of Electron. Mater. & Devices, Leibniz Univ. Hannover, Hannover, Germany
Abstract :
Ion implantation of boron is a promising technique for the preparation of p-type emitters in n-type cells. We use rapid thermal annealing with temperatures up to 1250 °C and annealing durations between 6 s and 20 min to anneal the implant-induced crystal defects. Experimental J0e is compared with simulated and measured defect densities. Perfect dislocation loops are identified to be the dominating defect species after rapid thermal annealing (RTA) above 1000 °C. Even for emitters with J0e values around 40 fA/cm2, defects are present within the valleys of the textured surfaces after annealing. On textured Al2O3 -passivated boron emitters, we measure J0e of 38 fA/cm 2 for a sheet resistance around 80 Ω/□ after very short annealing processes (1 min at 1200 °C).
Keywords :
aluminium compounds; boron; crystal defects; ion implantation; passivation; rapid thermal annealing; semiconductor materials; surface texture; Al2O3-B; Al2O3-passivated boron emitters; defect density; dislocation loops; electrical analysis; high boron ion-implanted emitters; high-temperature rapid thermal annealing; implant-induced crystal defects; n-type cells; p-type emitters; sheet resistance; structural analysis; surface texture; time 6 s to 20 min; Annealing; Boron; Density measurement; Doping; Ion implantation; Surface texture; Temperature measurement; Boron; crystal defects; ion implantation; photovoltaic; rapid thermal annealing (RTA); silicon;
Journal_Title :
Photovoltaics, IEEE Journal of
DOI :
10.1109/JPHOTOV.2014.2365468
