MONOCRYSTALLINE SI WAFFLES FOR THIN SOLAR-CELLS FABRICATED BY THE NOVEL PERFORATED-SILICON PROCESS

We apply the novel perforated-silicon process (''psi-process'') for th e fabrication of thin (a few microns thick) monocrystalline silicon la yers for solar cells with textured surfaces for efficient light trappi ng. A silicon layer grows epitaxially on the porous surface of a textu red monocrystalline Si substrate. Mechanical stress splits the porous layer and thereby separates the epitaxial layer from the substrate. X- ray diffraction analysis proves monocrystallinity for our 5.8-mu m-thi ck Si layer. Ray tracing simulations correctly model the optical refle ctance measurements. The simulations predict a maximum short-circuit c urrent of 36.5 mA/cm(2) for this waffle-shaped film when it is attache d to glass substrates.