This paper presents the history of the development of heterojunction silicon solar cells from the first studies of the amorphous silicon/crystalline silicon junction to the creation of HJT solar cells with novel structure and contact grid designs. In addition to explanation of the current advances in the field of research of this type of solar cells, the purpose of this paper is to show possible ways to improve the structure of the amorphous silicon/crystalline silicon-based solar cells for further improvement of the optical and electrical parameters of the devices by using of numerical simulation method and current hypotheses. This paper briefly describes the history, beginning from the first studies of and research of HJT-structure solar cells. It raises questions about the advantages and existing problems of optimization of HJT solar cells. The authors of this paper are proposing further ways of design development of HJT solar cells.
Wet chemical processing of single-crystal silicon wafers, including their texturing, is a key process step in the fabrication of high-efficiency solar cells. Methods of texturing single-crystal silicon wafers used in solar cell technology have been studied. Optimal texturing parameters have been determined for test samples, and the most effective etchant for texturing, a KOH–isopropanol solution, has been found.
Structures with aluminum-ion-implanted p+-n junctions formed in 26-μm-thick chemicalvapor-deposited-epitaxial 4H-SiC layers with an uncompensated donor concentration Nd−Na = (1–3) × 1015 cm−3 are irradiated with 167-MeV Xe ions at fluences of 4 × 109 to 1 × 1011 cm−2 and temperatures of 25 and 500°C. Then as-grown and irradiated structures are thermally annealed at a temperature of 500°C for 30 min. The as-grown, irradiated, and annealed samples are analyzed by means of cathodoluminescence, including the cross-sectional local cathodoluminescence technique, and electrical methods. According to the experimental data, radiation defects penetrate to a depth in excess of several tens of times the range of Xe ions. Irradiation of the structures at 500°C is accompanied by “dynamic annealing” of some low-temperature radiation defects, which increases the radiation resource of 4H-SiC devices operating at elevated temperatures.
1 March 2018 in Journal of Physics: Conference Series
This paper reports on the optimization of fabrication parameters of a heterojunction silicon solar cell using computer simulations and comparison of the simulation data with experimental results. The optimization of the photovoltaic devices was performed with respect to the thicknesses of amorphous silicon layers. As a result, a reasonable correlation between the simulation data and experimental results is observed within the acceptable margin of error with respect to heterojunction silicon solar cells with efficiency exceeding 20%.
Impedance spectroscopy provides relevant knowledge on the recombination and extraction of photogenerated charge carriers in various types of photovoltaic devices. In particular, this method is of great benefit to the study of crystalline silicon (c-Si)-based solar cells, a market-dominating commercial technology, for example, in terms of the comparison of various types of c-Si devices. This study investigates the dark and light electrophysical characteristics of a heterojunction silicon solar cell fabricated using plasma-enhanced chemical vapor deposition. The measurements are performed at various applied biases, enabling the determination of complex resistance, characteristic time, capacitive response and impurity concentration within the semiconductor junction and to correlate them with the device performance. In addition, the impedance spectra of the studied cell were investigated as a function of temperature. Studies of the frequency and temperature dependences of capacitance do not reveal a significant presence of thermally activated centers of free carrier capture, concomitant with a very small value of the activation energy extracted from an Arrhenius-type analysis. This leads to a conclusion that these centers are likely not impactful on the device operation and efficiency.
The paper reports on the results of simulations of output characteristics of silicon solar cells based on the amorphous silicon–crystalline silicon heterojunction. In addition, the prospect of...