Numerical 3D-Simulation of Micromorph Silicon Thin Film Solar Cells

2011 ◽  
Vol 1321 ◽  
Author(s):  
Stefan Geißendörfer ◽  
Karsten von Maydell ◽  
Carsten Agert
Keyword(s):  
Solar Cells ◽  
Complex Refractive Index ◽  
Silicon Thin Film ◽  
3 Dimensional ◽  
Force Microscopy ◽  
Atomic Force ◽  
Optical Generation ◽  
Surface Topographies ◽  
2D And 3D ◽  
Optical Generation Rate

ABSTRACTIn this contribution 1, 2 and 3-dimensional simulations of micromorph silicon solar cells are presented. In order to simulate solar cells with rough interfaces, the surface topographies were measured via atomic force microscopy (AFM) and transferred into the commercial software Sentaurus TCAD (Synopsys). The model of the structure includes layer thicknesses and optoelectronic parameters like complex refractive index and defect structure. Results of the space resolved optical generation rates by using of the optical solver Raytracer are presented. The space resolved optical generation rate inside the semiconductor layers depends on the structure of the transparent conductive oxides (TCO) interface. In this contribution the influence of different optical generation rates on the electrical characteristics of the solar cell device are investigated. Furthermore, the optical and electrical results of the 1D, 2D and 3D structures, which have equal layer thicknesses and optoelectronic parameters, are compared.

SELF-ASSEMBLED Ge-DOTS FOR Si SOLAR CELLS

2002 ◽  
Vol 16 (28n29) ◽  
pp. 4347-4351 ◽  
Author(s):  
H. PRESTING ◽  
J. KONLE ◽  
H. KIBBEL
Keyword(s):  
Solar Cells ◽  
Open Circuit Voltage ◽  
Elevated Temperatures ◽  
Growth Conditions ◽  
Open Circuit ◽  
3 Dimensional ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
P Type

Silicon solar cells with embedded germanium (Ge) layers deposited as 3-dimensional islands in the Stranski-Krastanov growth mode have been grown by molecular beam epitaxy (MBE) to enhance the efficiency of Si thin film solar cells. The Ge-layers increase the infrared absorption in the base of the cell to achieve higher photocurrent which should overcome the loss in the open circuit voltage due to incorporation of a smaller bandgap material in the heterostructure. Up to 75 layers of Ge, each about 8 monolayers (ML) thick, separated by Si-spacer layers (9-18nm) have been deposited at rather elevated temperatures (700°C) on a standard 10Ωcm p-type Si-substrate. Island densities of 1011 cm -2 have been achieved by use of antimony (Sb) as surfactant. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were used to characterize the growth of Ge-islands under variuos growth conditions. Photocurrent measurements exhibit a higher photo-response in the infrared regime but a lower open circuit voltage of the fabricated solar cells compared to a Si-reference cell.

Electroluminescence mapping of CuGaSe2 solar cells by atomic force microscopy

2006 ◽  
Vol 89 (14) ◽  
pp. 143120 ◽  
Author(s):  
Manuel J. Romero ◽  
C.-S. Jiang ◽  
J. Abushama ◽  
H. R. Moutinho ◽  
M. M. Al-Jassim ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Solar Cells ◽  
Force Microscopy ◽  
Atomic Force

Imaging Electron Transport across Grain Boundaries in an Integrated Electron and Atomic Force Microscopy Platform: Application to Polycrystalline Silicon Solar Cells

2009 ◽  
Vol 1153 ◽  
Author(s):  
Manuel J Romero ◽  
Fude Liu ◽  
Oliver Kunz ◽  
Johnson Wong ◽  
Chun-Sheng Jiang ◽  
...  
Keyword(s):  
Thin Films ◽  
Atomic Force Microscopy ◽  
Solar Cells ◽  
Electron Transport ◽  
Grain Boundaries ◽  
Polycrystalline Silicon ◽  
High Energy ◽  
Dominant Factor ◽  
Force Microscopy ◽  
Atomic Force

AbstractWe have investigated the local electron transport in polycrystalline silicon (pc-Si) thin-films by atomic force microscopy (AFM)-based measurements of the electron-beam-induced current (EBIC). EVA solar cells are produced at UNSW by <i>EVAporation</i> of a-Si and subsequent <i>solid-phase crystallization</i>–a potentially cost-effective approach to the production of pc-Si photovoltaics. A fundamental understanding of the electron transport in these pc-Si thin films is of prime importance to address the factors limiting the efficiency of EVA solar cells. EBIC measurements performed in combination with an AFM integrated inside an electron microscope can resolve the electron transport across individual grain boundaries. AFM-EBIC reveals that most grain boundaries present a high energy barrier to the transport of electrons for both p-type and n-type EVA thin-films. Furthermore, for p-type EVA pc-Si, in contrast with n-type, charged grain boundaries are seen. Recombination at grain boundaries seems to be the dominant factor limiting the efficiency of these pc-Si solar cells.

Emerging Conductive Atomic Force Microscopy for Metal Halide Perovskite Materials and Solar Cells

2020 ◽  
Vol 10 (10) ◽  
pp. 1903922 ◽  
Author(s):  
Haonan Si ◽  
Suicai Zhang ◽  
Shuangfei Ma ◽  
Zhaozhao Xiong ◽  
Ammarah Kausar ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Solar Cells ◽  
Metal Halide ◽  
Conductive Atomic Force Microscopy ◽  
Force Microscopy ◽  
Atomic Force ◽  
Perovskite Materials ◽  
Metal Halide Perovskite ◽  
Halide Perovskite

scholarly journals From Matrix Vesicles to Miniature Rocks: Evolution of Calcium Deposits in Calf Costochondral Junctions

Cartilage ◽  
2020 ◽  
pp. 194760352094122
Author(s):  
Jakub Jaroszewicz ◽  
Piotr Bazarnik ◽  
Anna Osiecka-Iwan ◽  
Anna Hyc ◽  
Emilia Choinska ◽  
...  
Keyword(s):  
Matrix Vesicles ◽  
Cartilage Matrix ◽  
X Ray Diffraction ◽  
3 Dimensional ◽  
Force Microscopy ◽  
Proliferative Zone ◽  
Atomic Force ◽  
Calcified Cartilage ◽  
Zone Of Provisional Calcification ◽  
Calcium Deposits

Objective Initial stages of cartilage matrix calcification depend on the activity of matrix vesicles. The purpose of the study was to describe how calcified matrix vesicles join into larger structures, to present their up-to-date undescribed 3-dimensional image, and to observe how calcified matrix relates to chondrocyte lacunae. Design Calcified cartilage was obtained from the zone of provisional calcification of calf costochondral junctions, then enzymatically isolated and studied by microtomography, scanning electron microscopy, atomic force microscopy and X-ray diffraction, and Fourier transform infrared spectroscopy. Results Hyaluronidase digestion released packets of granules surrounded by the cartilage matrix. Further digestion, with collagenase and trypsin, removed matrix and exposed granules with dimensions within 50 to 150 nm range, which we consider as equivalent of calcified matrix vesicles. Granules joined into larger groups with dimensions of 0.5 to 2 μm, which we call globular units. Certain matrix vesicles appeared well connected but contained globular units that had spaces filled with electron lucent material, presumably matrix or chondrocyte remnants. Globular units were organized into massive structures taking the shape of oval plates. Comparison of these plates with lacunae containing isogenous groups of chondrocytes from proliferative zone of costochondral junction suggests that the cells from a single lacuna were responsible for the formation of one plate. The plates were connected with each other and extended over provisional calcification zone. Conclusions The outcome showed how particular calcified matrix vesicles associate into globular units, which organize into massive structures assuming the shape of oval plates and eventually cover large areas of cartilage matrix.

Characterization and Optimization of The Tco/a-Si:H(,B) Interface for Solar Cells by In-Situ Ellipsometry and Sims/XPS Depth Profiling

1994 ◽  
Vol 336 ◽  
Author(s):  
H.N. Wanka ◽  
E. Lotter ◽  
M.B. Schubert
Keyword(s):  
Solar Cells ◽  
Light Trapping ◽  
Hydrogen Plasma ◽  
Depth Profiling ◽  
Trapping Efficiency ◽  
Force Microscopy ◽  
Hydrogen Plasmas ◽  
Atomic Force ◽  
20 Nm

ABSTRACTThe chemical reactions at the surface of transparent conductive oxides (SnO2, ITO and ZnO) have been studied in silane and hydrogen plasmas by in-situ ellipsometry and by SIMS as well as XPS depth profiling. SIMS and XPS of the interface reveal an increasing amount of metallic phases upon lowering a-Si:H growth rates (controlled by plasma power), indicating that the ion and radical impact is more than compensated by protecting the surface by a rapidly growing a-Si:H film. Hence, optical transmission of TCO films as well as the efficiency of solar cells can be improved if the first few nanometers of the p-layer are grown at higher rates. Comparing a-Si:H deposition on top of different TCOs, reduction effects on ITO and SnO2 have been detected whereas ZnO appeared to be chemically stable. Therefore an additional shielding of the SnO2 surface by a thin ZnO layer has been investigated in greater detail. Small amounts of H are detected close to the ZnO surface by SIMS after hydrogen plasma treatment, but no significant changes occur to the optical and electrical properties. In-situ ellipsometry indicates that a ZnO layer as thin as 20 nm completely protects SnO2 from being reduced to metallic phases. This provides for shielding of textured TCOs, and hence rising solar cell efficiencies, too. Regarding light trapping efficiency we additionally investigated the smoothing of initial TCO texture when growing a-Si:H on top by combining atomic force microscopy and spectroscopie ellipsometry.

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