Simultaneous recrystallization, phosphorous diffusion and antireflection coating of silicon films using laser treatment

Abstract

Laser technique application to polycrystalline silicon thin-film solar cell fabrication on glass substrates has received appreciable attention. In this paper, a laser-doping technique is developed for plasma-deposited amorphous silicon film. A process involving recrystallization, phosphorous diffusion and antireflection coating can be achieved simultaneously using the laser annealing process. The doping precursor, a phosphorous-doped titanium dioxide (TiO2) solution, is synthesized using a sol-gel method and spin-coated onto the sample. After laser irradiation, the polycrystalline silicon grain size was about 0.5 similar to 1.0 mu m with a carrier concentration of 2 x 10(19) cm(-3) and electron mobility of 92.6 cm(2)/V s. The average polycrystalline silicon reflectance can be reduced to a value of 4.65% at wavelengths between 400 and 700 nm, indicating the upper TiO2, film of antireflection coating. (c) 2005 Elsevier B.V. All rights reserved.