ФОТОЭЛЕКТРИЧЕСКИЕ ПРЕОБРАЗОВАТЕЛИ В СИСТЕМЕ СО СПЕКТРАЛЬНЫМ РАСЩЕПЛЕНИЕМСОЛНЕЧНОЙ ЭНЕРГИИ

This paper presents results on the simulation of photo converters in a spectral splitting system where solar radiation is separated into three spectral ranges (∆λ1<500 nm, ∆λ2 = 500−725 nm and ∆λ3>725 nm) by means of dichroic filters and then converted to electrical energy by photoconverters based on InGaN/GaN, GaAs/AlGaAs single−junction heterostructures and monocrystalline silicon c−Si. Special attention is paid to the absorption spectrum spreading due to more efficient conversion of the ultraviolet part of the spectrum. The total efficiency of the system varies from 21% to 37% depending on the design of heterostructures.Представлены результаты моделирования фотоэлектрических преобразователей в системе со спектральным расщеплением солнечной энергии, в которой солнечное излучение разделяется с помощью дихроичных фильтров на три спектральных диапазона (∆λ1 < 500 нм, ∆λ2 = 500÷725 нм, ∆λ3 > 725 нм) и затем преобразуется в электроэнергию фотоэлектрическими преобразователями на основе однопереходных гетероструктур InGaN/GaN, GaAs/AlGaAs и монокристаллического кремния c−Si. Особое внимание уделено исследованию расширения спектрального диапазона поглощения системы за счет более эффективного преобразования ультрафиолетовой части спектра. Суммарный КПД системы на всем спектре варьируется от 21 до 37 % в зависимости от дизайна гетероструктур однопереходных фотоэлектрических пре-образователей и вариантов оптических систем

Microscopic Examination of the Silicon Surface Subjected to High-Dose Silver Implantation

© 2019, Pleiades Publishing, Ltd. Abstract: Low-energy (E = 30 keV) Ag + ions have been implanted into single-crystalline Si wafers (c-Si) with an implantation dose varying from 1.25 × 10 15 to 1.5 × 10 17 ions cm –2 and an ion beam current density varying from 2 to 15 μA/cm 2 . The surface morphology of implanted wafers has been examined using scanning electron microscopy, transmission electron microscopy, and atomic force microscopy, and their structure has been studied by means of reflection high-energy electron diffraction and elemental microanalysis. It has been shown that for minimal irradiation doses used in experiments, the surface layer of c-Si experiences amorphization. It has been found that when the implantation dose is in excess of the threshold value (~3.1 × 10 15 ions cm –2 ), Ag nanoparticles uniformly distributed over the Si surface arise in the irradiated Si layer. At a dose exceeding 10 17 ions cm –2 , a porous Si structure is observed. In this case, the Ag nanoparticle size distribution becomes bimodal with coarse particles localized at the walls of Si pores

Microscopic Examination of the Silicon Surface Subjected to High-Dose Silver Implantation

© 2019, Pleiades Publishing, Ltd. Abstract: Low-energy (E = 30 keV) Ag + ions have been implanted into single-crystalline Si wafers (c-Si) with an implantation dose varying from 1.25 × 10 15 to 1.5 × 10 17 ions cm –2 and an ion beam current density varying from 2 to 15 μA/cm 2 . The surface morphology of implanted wafers has been examined using scanning electron microscopy, transmission electron microscopy, and atomic force microscopy, and their structure has been studied by means of reflection high-energy electron diffraction and elemental microanalysis. It has been shown that for minimal irradiation doses used in experiments, the surface layer of c-Si experiences amorphization. It has been found that when the implantation dose is in excess of the threshold value (~3.1 × 10 15 ions cm –2 ), Ag nanoparticles uniformly distributed over the Si surface arise in the irradiated Si layer. At a dose exceeding 10 17 ions cm –2 , a porous Si structure is observed. In this case, the Ag nanoparticle size distribution becomes bimodal with coarse particles localized at the walls of Si pores