Enhanced optical absorption of AlxGa1-xAs nanoarrays with variable Al composition structure for solar cell applications. (September 2021)

• Record Type: Journal Article
• Authors: Liu, Lei; Diao, Yu; Lv, Zhisheng; Sun, Yan
• Is Part Of: Materials research bulletin. Volume 141(2021)
• Publication Date: 2021-09
• Subjects: Variable Al composition -- Nanostructure array -- Light capture -- Finite element method; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2021.111364
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: The optical absorption mechanisms of Alx Ga1-x As nanostructures are simulated. The cylinder structure exhibits better performance upon photon absorption. High Al composition gradient is conductive to short-wavelength adsorption. Suitable arrangement of sublayer thickness maximize absorption enhancement. Abstract: In this study, various variable Al composition nanoarray structures are proposed and designed to achieve high-efficient light capture. The COMSOL Multiphysics package based on finite element method is utilized to investigate the optical absorption performance of cylinder, circular frustum and inverted circular frustum nanoarray structures. The effects of different geometric diameters, sub-layer thickness distribution and Al composition range on the optical properties of various nanostructures are also analyzed in detail. The results show that the designed cylinder structure can obtain optical absorption enhancement of more than 5 % and 3 % compared with the circular frustum and inverted circular frustum structure. Besides, the reasonable design of sub-layer thickness distribution can be selected to allow different nanostructures to obtain effective optical absorption enhancement performance. In addition, the larger Al composition range distribution design can effectively improve the absorption for short-wavelength photons. The design principles proposed in this work will provide a reference for selecting appropriate parameters for solar cell applications.