Ion Implanted Grating Type Si Solar Cells

Abstract

Silicon grating-type solar cells have been fabricated by ion-implantation techniques. The cells as-fabricated showed maximum V oc of 0.54 V, and maximum I sc of 34 mA/cm2 (without AR coating) under an AM1 illumination, and maximum FF of 0.68. The series resistance problems were examined, and metal gridding superimposed on the grating was found essential. The effects of impurity profiles and the annealing conditions have been studied. For a fixed value of junction depth, the cell output peaked for doping levels around 1019 cm-3. For a fixed grating geometry, it was found within the limits of the implanted ion concentration, the deeper the junction the higher the cell efficiency, which is in contrast to the commonly shallow junction cells. It was also found that slow cooling from thermal annealing is essential in improving the ion-implanted solar cell efficiencies.

Fabrication of Quasi-Sinusoidal Surface Relief Optical Transmission Gratings in Pyrex and IOG Glasses by Implantation with Oxygen and Nitrogen Ion Microbeams of the 5–6 MeV Energy Range

“…Hwang and his coauthors fabricated ion beam implanted gratings in silicon solar cells . They implanted boron ions of the energy range of 20–180 keV at fluences between 10 11 and 10 15 ion/cm 2 .…”

“…Hwang and his coauthors fabricated ion beam implanted gratings in silicon solar cells. 18 They implanted boron ions of the energy range of 20–180 keV at fluences between 10 11 and 10 15 ion/cm 2 . Then, by combining various fabrication steps, like chemical etching, with the implantation, they obtained Damman gratings with grating constants of 125 μm in both directions.…”