Study on AlxGa1-xAs nanocones with variable Al composition structures for highly efficient light trapping

Abstract

In this study, various Al x Ga 1-x As nanostructure arrays with variable Al composition are proposed and designed for highly efficient light capture. The optical properties of the proposed nanocone array with variable Al composition have been numerically investigated by COMSOL Multiphysics package based on the finite element method (FEM), and compared with the counterparts of cylinder and conical frustum. The results show that the variable composition Al x Ga 1-x As nanocones with uniform sublayer distribution thickness can obtain an ultimate efficiency of 37.3%, which is higher than that of the cylindrical and conical frustum structures under the same conditions. In addition, the effects of geometric parameters of nanostructures on the light absorption of nanoarrays with different shape changing components are studied. Taking the variable component Al x Ga 1-x As nanocone structure as an example, increasing the Al component range in the axial direction of the nanocone can significantly improve the absorption of short-wavelength light, which increases the overall absorption efficiency. In addition, for a specific Al composition distribution range, a uniform thickness distribution design of unit sub-layer in nanocone along the z-axis direction can provide optical absorption enhancement of more than 1.8% and 0.9% over than the decreasing and increasing distribution design. The design principles proposed in this work will provide a reference for selecting appropriate parameters in solar cell applications.

Impact of aluminum concentration and grading configuration of AlxGa1-xAs nanostructures for solar absorber applications

“…Such a study has used NWs without substrate where the cylindrical and truncated cone NWs have achieved a short circuit current density of 23.1% and 26.8%. 36 Furthermore, Liu et al 37 have introduced Al x Ga 1−x As NCs with a top diameter of 0 nm at Al concentration from 0 to 0.8. Group III-V semiconductors' direct bandgap with strong absorption make them perfect for SC applications atop Si material, the dominant SC platform due to its widespread exploration and good light absorption.…”

“…Such a study has used NWs without substrate where the cylindrical and truncated cone NWs have achieved a short circuit current density of 23.1% and 26.8% 36 . Furthermore, Liu et al 37 . have introduced AlxGa1−xAs NCs with a top diameter of 0 nm at Al concentration from 0 to 0.8.…”