Tim Frijnts
Helmholtz Zentrum für Materialien und Energie Berlin, Germany
Title: Laser processing of solar cells on laser crystalized silicon
Biography
Biography: Tim Frijnts
Abstract
Low quality silicon was deposited on silicon oxynitride layers on glass. This was then crystallized over a liquid phase using a line-shaped, 808 nm, continuous wave, diode laser, in order to obtain crystalline silicon with grain size comparable to multicrystalline silicon wafers. A 1064 nm picosecond laser, applied through the glass, was used to make isolation scribes which define the cell area and also allow for the fabrication of a mini-module consisting of series connected cells. A 355 nm picosecond laser, in combination with a white resin layer, was used to structure the contacting layers of the backside contacted solar cell, thereby avoiding the use of expensive and cumbersome lithography processes. Finally, a 532 nm nanosecond laser was used to modify the metal-silicon contact in order to reduce the contact resistance, resulting in a new highest efficiency for this cell type of 12%.