Single wire radial junction photovoltaic devices fabricated using aluminum catalyzed silicon nanowires

Abstract

Single nanowire radial junction solar cell devices were fabricated using Si nanowires synthesized by Al-catalyzed vapor-liquid-solid growth of the p(+) core (Al auto-doping) and thin film deposition of the n(+)-shell at temperatures below 650 °C. Short circuit current densities of 11.7 mA cm(-2) were measured under 1-sun AM1.5G illumination, showing enhanced optical absorption. The power conversion efficiencies were limited to < 1% by the low open circuit voltage and fill factor of the devices, which was attributed to junction shunt leakage promoted by the high p(+)/n(+) doping. This demonstration of a radial junction device represents an important advance in the use of Al-catalyzed Si nanowire growth for low cost photovoltaics.

Silicon nanowire–silver indium selenide heterojunction photodiodes

“…Among the many available material systems, Si nanowires have received particular interest because of their compatibility with present electronic and photovoltaic technologies. Many practical, electronic and optoelectronic device applications have been demonstrated using Si nanowires, including transistors [2,3], homoand heterojunction diodes [4,5], solar cells [6][7][8][9] and batteries [10,11].…”

Wet – Chemically Etched Silicon Nanowire Solar Cells: Fabrication and Advanced Characterization

“…SiNWs enable several concepts of efficient solar cell geometries. The charge carrier dividing junction (p-n or Schottky type) can be applied in a radial [23,24] or axial [25,26] concept inside the NWs and a possible solution is also the wrapping of NWs with a second material [27]. In this work, we used a semiconductor-insulator-semiconductor (SIS) heterojunction solar cell concept that has already been developed in the 1970s [28][29][30].…”

Controlled faceting and morphology for light trapping in aluminum-catalyzed silicon nanostructures

“…Previous reports have demonstrated the fabrication of aluminumcatalyzed nanowires in both ultra-high vacuum and low-pressure (100-500 Torr) environments [9][10][11][12][13], and aluminum incorporation into the wires has been reported at concentrations of greater than 10 20 atoms/cm 3 resulting in wires that are p-type after growth [14,15]. The light trapping properties of VLSgrown nanowire arrays are well known, and single-wire devices have been demonstrated using aluminum-catalyzed wires [16,17], so direct integration of aluminum-catalyzed nanowire arrays into photovoltaic devices should be achievable. Furthermore, fabrication of black silicon textured devices using aluminum-catalyzed nanowires could ultimately allow for the consolidation of the texturing and junction formation into a single process.…”