Optimization and Fabrication of Heterojunction Silicon Solar Cells Using an Experimental-Industrial Facility AK-1000 Inline

Introduction. Heterojunction silicon solar cells represent one of the most promising directions for the development of solar photovoltaics. This is due to both their high power conversion efficiency and reasonable likelihood for further growth in performance, as well as good commercial potential of this technology, which relies on a transition from conventional diffusion-based processes to thin film deposition.Aim. The paper describes results of optimization and fabrication of heterojunction silicon solar cells using the AK-1000 inline tool, adapted for processing of 6-inch wafers.Materials and methods. In the manufacturing of solar cells, crystalline silicon wafers were subjected to wet chemical processes, and then electron, hole, and intrinsic types of conductivity of the layers based on amorphous silicon were deposited by plasma-chemical deposition. Precipitation of oxide transparent conductive layers was carried out by magnetron sputtering. To optimize the processes of obtaining solar cells, measurements of the reflection coefficient, of lifetime of minority carriers, and of current – voltage characteristics were used.Results. As a result of the work, heterojunction solar cells were obtained in a laboratory in Kazakhstan with an efficiency of 20% without using of traditional diffusion processes for solar cells manufacturing.Conclusions. The output parameters associated with light conversion efficiency demonstrate the possibility of further optimization of the parameters affecting the performance of heterojunction solar cells.Introduction. Heterojunction silicon solar cells represent one of the most promising directions for the development of solar photovoltaics. This is due to both their high power conversion efficiency and reasonable likelihood for further growth in performance, as well as good commercial potential of this technology, which relies on a transition from conventional diffusion-based processes to thin film deposition.Aim. The paper describes results of optimization and fabrication of heterojunction silicon solar cells using the AK-1000 inline tool, adapted for processing of 6-inch wafers.Materials and methods. In the manufacturing of solar cells, crystalline silicon wafers were subjected to wet chemical processes, and then electron, hole, and intrinsic types of conductivity of the layers based on amorphous silicon were deposited by plasma-chemical deposition. Precipitation of oxide transparent conductive layers was carried out by magnetron sputtering. To optimize the processes of obtaining solar cells, measurements of the reflection coefficient, of lifetime of minority carriers, and of current – voltage characteristics were used.Results. As a result of the work, heterojunction solar cells were obtained in a laboratory in Kazakhstan with an efficiency of 20% without using of traditional diffusion processes for solar cells manufacturing.Conclusions. The output parameters associated with light conversion efficiency demonstrate the possibility of further optimization of the parameters affecting the performance of heterojunction solar cells

Indirect Study of the 16O+16O Fusion Reaction Toward Stellar Energies by the Trojan Horse Method

The 16 O+ 16 O fusion reaction is important in terms of the explosive oxygen burning process during late evolution stage of massive stars as well as understanding of the mechanism of low-energy heavy-ion fusion reactions. We aim to determine the excitation function for the most major exit channels, α + 28 Si and p + 31 P, toward stellar energies indirectly by the Trojan Horse Method via the 16 O( 20 Ne , α 28 Si) α and 16 O( 20 Ne , p 31 P) α three-body reactions. We report preliminary results involving reaction identification, and determination of the momentum distribution of α - 16 O intercluster motion in the projectile 20 Ne nucleus

Development of a mobile independent solar power plant based on solid-state heterojunction photocells for agricultural purposes

Mathematical simulation of temperature distribution on double-sided solar cells has been carried out. Differences in the configuration of photoelectric converters prove to solely amount to the fact that a double-sided solar cell has a more efficient heat sink at the rear side. Furthermore double-sided solar cells exhibit higher power conversion performance. Calculations confirm the correctness of giving preference to double-sided solar cells which is of great importance for the photoelectric converter design developed by us. Analysis of market-available photovoltaic technologies of solar energy to electric power conversion has led to the development of a photovoltaic converter on the basis of double-sided silicon heterojunction solar cells. The configuration developed is a moving platform having a photovoltaic cell array mounted on it and a light flux collector. A double-axis tracking system has been developed for the general case of planar attachment of solar cell modules. A 350 mm stroke drive provides for movement in the north-south direction and a 450 mm stroke drive, in the east-west direction. The task has been outlined to find the required arm for providing symmetrical positioning at the maximum rotation angle about the axis. As a result, technical solutions have been developed for the north-south and the east-west directions. Furthermore a schematic wiring diagram has been designed to implement the preset solar tracking system algorithm. The system is also fitted with a GPS/GLONASS module for system precision positioning and time synchronization

Optimization and Fabrication of Heterojunction Silicon Solar Cells Using an Experimental-Industrial Facility AK-1000 Inline

Introduction. Heterojunction silicon solar cells represent one of the most promising directions for the development of solar photovoltaics. This is due to both their high power conversion efficiency and reasonable likelihood for further growth in performance, as well as good commercial potential of this technology, which relies on a transition from conventional diffusion-based processes to thin film deposition.Aim. The paper describes results of optimization and fabrication of heterojunction silicon solar cells using the AK-1000 inline tool, adapted for processing of 6-inch wafers.Materials and methods. In the manufacturing of solar cells, crystalline silicon wafers were subjected to wet chemical processes, and then electron, hole, and intrinsic types of conductivity of the layers based on amorphous silicon were deposited by plasma-chemical deposition. Precipitation of oxide transparent conductive layers was carried out by magnetron sputtering. To optimize the processes of obtaining solar cells, measurements of the reflection coefficient, of lifetime of minority carriers, and of current – voltage characteristics were used.Results. As a result of the work, heterojunction solar cells were obtained in a laboratory in Kazakhstan with an efficiency of 20% without using of traditional diffusion processes for solar cells manufacturing.Conclusions. The output parameters associated with light conversion efficiency demonstrate the possibility of further optimization of the parameters affecting the performance of heterojunction solar cells

Indirect Study of the 16O+16O Fusion Reaction Toward Stellar Energies by the Trojan Horse Method

The 16O+16O fusion reaction is important in terms of the explosive oxygen burning process during late evolution stage of massive stars as well as understanding of the mechanism of low-energy heavy-ion fusion reactions. We aim to determine the excitation function for the most major exit channels, α+28Si and p+31P, toward stellar energies indirectly by the Trojan Horse Method via the 16O(20Ne, α28Si)α and 16O(20Ne, p31P)α three-body reactions. We report preliminary results involving reaction identification, and determination of the momentum distribution of α-16O intercluster motion in the projectile 20Ne nucleus

Charge-changing cross sections for Ca42-51 and effect of charged-particle evaporation induced by neutron-removal reactions

Charge-changing cross sections sigma(CC) for Ca42-51 on a carbon target at around 280 MeV/nucleon have been measured. Though the existing point-proton radii r(p) of Ca isotopes increase as the neutron number increases, the measured sigma(CC) data show a significant decrease, which is against the expectation from a simple Glauber-like model. We found that this observed phenomenon could be attributed to the charged-particle evaporation effect induced by the neutron-removal reaction. By taking the evaporation effect into account, various sigma(CC) data sets for nuclides from C to Fe isotopes on C-12 measured at around 280 MeV/nucleon are reproduced with a standard deviation of 1.6%. It is also clarified that this evaporation effect becomes negligibly small in the neutron-rich region. The evaluated relation between sigma(CC) and r(p) using the current model indicates that sigma(CC) data for neutron-rich Ca isotopes (A >= 51) are highly sensitive to r(p). This high sensitivity potentially allows one to determine the r(p) of very neutron-rich nuclei.11Nsciescopu

Swelling of Doubly Magic 48^{48}Ca Core in Ca Isotopes beyond N = 28

Interaction cross sections for $^{42\textrm{-}51}$Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number $N=28$. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and the Mean-Field calculations point out that this anomalous enhancement of the nuclear size beyond $N=28$ results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare $^{48}$Ca core in Ca isotopes beyond $N=28$.Comment: 6 pages, 3 figure