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Metal nanoparticle-enhanced photocurrent in GaAs photovoltaic structures with microtextured interfaces.

Dmitruk NL, Borkovskaya OY, Mamontova IB, Mamykin SV, Malynych SZ, Romanyuk VR - Nanoscale Res Lett (2015)

Bottom Line: Three nanoparticle deposition methods have been checked: 1) photoinduced chemical deposition of Au from aqueous AuCl3 solution forming nanowires on the ridges of quasigrating-type surface microrelief, 2) deposition of Ag nanoparticles from colloidal suspension on the GaAs substrate covered with poly(vinylpyridine), and 3) drop and dry deposition of Au/SiO2 core-shell nanoparticles from aqueous colloid solution.The comprehensive investigation of optical reflectance, photoelectric, and electrical characteristics of the fabricated barrier structures has shown the highest photovoltaic parameters for surface microrelief of quasigrating-type and electroless Au nanoparticle deposition.The analysis of characteristics obtained allowed us also to define the mechanisms of the total photocurrent enhancement.

View Article: PubMed Central - PubMed

Affiliation: Department of Polaritonic Optoelectronics, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 41 Nauky av., Kyiv, 03028 Ukraine.

ABSTRACT
The photocurrent enhancement effect caused by Au and Ag nanoparticles for GaAs-based photovoltaic structures of surface barrier or p-n junction type with microtextured interfaces has been investigated in dependence on the conditions of nanoparticles deposition and, respectively, on the shape and local dielectric environment of obtained nanoparticle arrays. Three nanoparticle deposition methods have been checked: 1) photoinduced chemical deposition of Au from aqueous AuCl3 solution forming nanowires on the ridges of quasigrating-type surface microrelief, 2) deposition of Ag nanoparticles from colloidal suspension on the GaAs substrate covered with poly(vinylpyridine), and 3) drop and dry deposition of Au/SiO2 core-shell nanoparticles from aqueous colloid solution. The comprehensive investigation of optical reflectance, photoelectric, and electrical characteristics of the fabricated barrier structures has shown the highest photovoltaic parameters for surface microrelief of quasigrating-type and electroless Au nanoparticle deposition. The analysis of characteristics obtained allowed us also to define the mechanisms of the total photocurrent enhancement.

No MeSH data available.


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The spectral dependencies of reflectance (Rp) and the spectra of light transmittance. The spectral dependencies of Rp at near-normal incidence (10°) of light on GaAs with flat surface (a) and with surface microrelief of quasigrating type (b) before (1) and after (2) Au nanoparticles deposition. (c) The spectra of the light transmittance through the layer of aqueous suspension of Ag NP (1) and the ratio of light transmittance through Au/Ag NP/glass and Au/glass structures with Au layer thickness of 30 nm (2).
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Fig3: The spectral dependencies of reflectance (Rp) and the spectra of light transmittance. The spectral dependencies of Rp at near-normal incidence (10°) of light on GaAs with flat surface (a) and with surface microrelief of quasigrating type (b) before (1) and after (2) Au nanoparticles deposition. (c) The spectra of the light transmittance through the layer of aqueous suspension of Ag NP (1) and the ratio of light transmittance through Au/Ag NP/glass and Au/glass structures with Au layer thickness of 30 nm (2).

Mentions: To determine the change of optical properties of investigated structures due to nanoparticles deposition, the spectra of the light reflection from the flat and microtextured GaAs surfaces before and after nanoparticles deposition were measured (Figure 3a,b). The spectra of specular reflection of p- and s-polarized light were measured at near-normal incidence of light (approximately 10°) on GaAs surface over the range of GaAs fundamental photosensitivity (0.4 to 0.9 μm). In the case of structures with quasigrating type of microrelief, the plane of light incidence was disposed perpendicularly to relief lines. A simplified model of this structure, shown in Figure 2a, where periodic ensemble of metal nanowires with cylindrical shape was situated on the tops of semiconductor surface relief with triangular shape, was used for the simulation of its optical properties (spectra of reflectance, transmittance, and generation rate of electron–hole pairs) [11]. The spectral peculiarities were shown to depend both on the polarization of light, on the depth and period of microrelief, and on the diameter of Au nanowires. Since the microrelief of quasigrating type has some distribution of grating periods, these peculiarities are smoothed. So, the depositions of Au nanoparticles on a flat surface and Au nanowires on the textured one exert both a similar effect on the light reflection spectrum, in particular the increase of Rp in a long-wave region and minimum at λ ≅ 0.5 μm, and a distinct one (Figure 3a,b). The wide maximum at λ ≅ 0.6 μm of the curve 2 in Figure 3b suggests the influence of SP/SPP excitation in Au nanowires. Besides, the spectra of the light transmittance through the glass with the same nanolayers of nanoparticles (satellite samples) were also measured (Figure 3c). The spectrum of the light transmittance through the nanolayer with Ag nanoparticles shows properties similar to the ones of transmittance spectrum for the layer of aqueous suspension of Ag NP. So, they are caused by scattering of light by Ag NP due to surface plasmon excitation on them.Figure 3


Metal nanoparticle-enhanced photocurrent in GaAs photovoltaic structures with microtextured interfaces.

Dmitruk NL, Borkovskaya OY, Mamontova IB, Mamykin SV, Malynych SZ, Romanyuk VR - Nanoscale Res Lett (2015)

The spectral dependencies of reflectance (Rp) and the spectra of light transmittance. The spectral dependencies of Rp at near-normal incidence (10°) of light on GaAs with flat surface (a) and with surface microrelief of quasigrating type (b) before (1) and after (2) Au nanoparticles deposition. (c) The spectra of the light transmittance through the layer of aqueous suspension of Ag NP (1) and the ratio of light transmittance through Au/Ag NP/glass and Au/glass structures with Au layer thickness of 30 nm (2).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385134&req=5

Fig3: The spectral dependencies of reflectance (Rp) and the spectra of light transmittance. The spectral dependencies of Rp at near-normal incidence (10°) of light on GaAs with flat surface (a) and with surface microrelief of quasigrating type (b) before (1) and after (2) Au nanoparticles deposition. (c) The spectra of the light transmittance through the layer of aqueous suspension of Ag NP (1) and the ratio of light transmittance through Au/Ag NP/glass and Au/glass structures with Au layer thickness of 30 nm (2).
Mentions: To determine the change of optical properties of investigated structures due to nanoparticles deposition, the spectra of the light reflection from the flat and microtextured GaAs surfaces before and after nanoparticles deposition were measured (Figure 3a,b). The spectra of specular reflection of p- and s-polarized light were measured at near-normal incidence of light (approximately 10°) on GaAs surface over the range of GaAs fundamental photosensitivity (0.4 to 0.9 μm). In the case of structures with quasigrating type of microrelief, the plane of light incidence was disposed perpendicularly to relief lines. A simplified model of this structure, shown in Figure 2a, where periodic ensemble of metal nanowires with cylindrical shape was situated on the tops of semiconductor surface relief with triangular shape, was used for the simulation of its optical properties (spectra of reflectance, transmittance, and generation rate of electron–hole pairs) [11]. The spectral peculiarities were shown to depend both on the polarization of light, on the depth and period of microrelief, and on the diameter of Au nanowires. Since the microrelief of quasigrating type has some distribution of grating periods, these peculiarities are smoothed. So, the depositions of Au nanoparticles on a flat surface and Au nanowires on the textured one exert both a similar effect on the light reflection spectrum, in particular the increase of Rp in a long-wave region and minimum at λ ≅ 0.5 μm, and a distinct one (Figure 3a,b). The wide maximum at λ ≅ 0.6 μm of the curve 2 in Figure 3b suggests the influence of SP/SPP excitation in Au nanowires. Besides, the spectra of the light transmittance through the glass with the same nanolayers of nanoparticles (satellite samples) were also measured (Figure 3c). The spectrum of the light transmittance through the nanolayer with Ag nanoparticles shows properties similar to the ones of transmittance spectrum for the layer of aqueous suspension of Ag NP. So, they are caused by scattering of light by Ag NP due to surface plasmon excitation on them.Figure 3

Bottom Line: Three nanoparticle deposition methods have been checked: 1) photoinduced chemical deposition of Au from aqueous AuCl3 solution forming nanowires on the ridges of quasigrating-type surface microrelief, 2) deposition of Ag nanoparticles from colloidal suspension on the GaAs substrate covered with poly(vinylpyridine), and 3) drop and dry deposition of Au/SiO2 core-shell nanoparticles from aqueous colloid solution.The comprehensive investigation of optical reflectance, photoelectric, and electrical characteristics of the fabricated barrier structures has shown the highest photovoltaic parameters for surface microrelief of quasigrating-type and electroless Au nanoparticle deposition.The analysis of characteristics obtained allowed us also to define the mechanisms of the total photocurrent enhancement.

View Article: PubMed Central - PubMed

Affiliation: Department of Polaritonic Optoelectronics, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 41 Nauky av., Kyiv, 03028 Ukraine.

ABSTRACT
The photocurrent enhancement effect caused by Au and Ag nanoparticles for GaAs-based photovoltaic structures of surface barrier or p-n junction type with microtextured interfaces has been investigated in dependence on the conditions of nanoparticles deposition and, respectively, on the shape and local dielectric environment of obtained nanoparticle arrays. Three nanoparticle deposition methods have been checked: 1) photoinduced chemical deposition of Au from aqueous AuCl3 solution forming nanowires on the ridges of quasigrating-type surface microrelief, 2) deposition of Ag nanoparticles from colloidal suspension on the GaAs substrate covered with poly(vinylpyridine), and 3) drop and dry deposition of Au/SiO2 core-shell nanoparticles from aqueous colloid solution. The comprehensive investigation of optical reflectance, photoelectric, and electrical characteristics of the fabricated barrier structures has shown the highest photovoltaic parameters for surface microrelief of quasigrating-type and electroless Au nanoparticle deposition. The analysis of characteristics obtained allowed us also to define the mechanisms of the total photocurrent enhancement.

No MeSH data available.


Related in: MedlinePlus