High Optical Absorption of Indium Sulfide Nanorod Arrays Formed by Glancing Angle Deposition

Abstract

Indium (III) sulfide has recently attracted much attention due to its potential in optical sensors as a photoconducting material and in photovoltaic applications as a wide direct bandgap material. On the other hand, optical absorption properties are key parameters in developing high photosensitivity photodetectors and high efficiency solar cells. We show that indium sulfide nanorod arrays produced by glancing angle deposition technique have superior absorption and low reflectance properties compared to conventional flat thin film counterparts. We observed an optical absorption value of approximately 96% for nanorods in contrast to 80% for conventional amorphous-to-polycrystalline thin films of indium sulfide. A photoconductivity response was also observed in the nanorod samples, whereas no measurable photoresponse was detected in conventional thin films. We give a preliminary description of the enhanced light absorption properties of the nanorods by using Shirley-George model which predicts diffusion of light by the roughness on the surface.

A Perspective on Nanowire Photodetectors: Current Status, Future Challenges, and Opportunities

“…The following are some examples of NW-based PDs of different materials demonstrated via the direct growth method: NWs of InAs [147], NWs of Si [148]- [152], nanorods of GaN [153], InP NWs/polymer hybrid photodiode [154], InN nanorod/poly(3-hexylthiophene) hybrids [155], NWs of ncCdSe [156], NWs of Ge [157], random network of silicon NWs [158], nanostructured amorphous-silicon (a-Si:H)/polymer hybrid photocells [159], nanopillars of GaInAs/InP [160], NWs of GaAs [161], NWs of GaN [162], NW network of ZnCdSe [163], nanorods of In 2 S 3 [164], GaN NW pin photodiode [165], nanorods of ZnO [166]- [169], silicon NW phototransistor [170], [171], and nanorods array of p-GaN/InGaN/nGaN [172].…”

SAD-GLAD core-shell nanorod arrays for fuel cell, photodetector, and solar cell electrode applications

“…Instead, GLAD is a physical self-assembly growth technique that can produce uniformly aligned arrays of 3D nanostructures with large aspect ratio, controllable size, separation, shape, and enhanced resistance to oxidation. [9]- [10] These characteristics are not easily attainable by other techniques. (2) The technique is very robust in that practically any inorganic elemental material or a combination of materials (for example, alloys and compounds, notably oxides and sulfides) can be grown on almost any substrate material including polymers, metals, semiconducting materials, glass, and oxides.…”

Progress in indium (III) sulfide (In 2 S 3 ) buffer layer deposition techniques for CIS, CIGS, and CdTe-based thin film solar cells

“…Indium (III) sulfide (In 2 S 3 ), an indium chalcogenide, is a III-VI semiconductor compound important for optoelectronic (Cansizoglu et al, 2010;Mughal et al, 2015), photoelectric (Ho, 2011), and photovoltaic (PV) applications Haleem et al, 2012 due to its stable chemical composition (Newell et al, 2011;Strausser et al, 1995), photoconductivity (Gilles et al, 1962), and luminescent characteristics (Springford, 1963) at ambient conditions. It functions as an n-type semiconductor with an optical bandgap of 2.1-2.3 eV Dutta et al, 2007); however, there is still controversy about whether it is has a direct or indirect bandgap.…”

“…In 2 S 3 crystallizes into three allotropic forms, namely, a-In 2 S 3 (cubic structure between 420°C and 754°C), b-In 2 S 3 (tetragonal structure below 420°C), and c-In 2 S 3 (trigonal structure above 754°C) (Lee et al, 2008). Among these crystallographic phases, b-In 2 S 3 has the widest applications (Mughal et al, 2015) due to its defective spinal structure (most stable) Tao et al, 2008, large photosensitivity (Warrier et al, 2013), and physical characteristics (Cansizoglu et al, 2010). With optimal physical properties, it can meet the requirement of a suitable buffer layer in TFSCs.…”