AMPS 1D Research Articles

Optimization of the performance of micromorph tandem solar cell a-Si/uc-Si

We have performed a Computer modeling using AMPS 1D and AFORS-HET for optimizing tandem cells on p-i-n/p-i-n configuration. We investigated the influence of the substrate temperature for doped layer deposition technique in the top cell performances and the influence of the thickness of the bottom cell in the density of current that present a crucial parameter in the current matching between subcells. The simulation results demonstrate in one hand that a top cell a-Si with doped layers deposited by PECVD with 1000C substrate temperature provides a notable increase in the efficiency, and in the other hand a bottom cell with 900nm thick intrinsic layer exhibit more density of current. The performances of micromorph cell obtained from simulation give a good agreement with experimental results and confirm the importance of the combination as a double junction solar cell

Modeling and optimization of CZTS kesterite solar cells using TiO2 as efficient electron transport layer

In this paper, a numerical simulation study via AMPS 1D simulator is carried out to investigate the degradation mechanisms occurred in hybrid Cu2(Zn,Sn)Se4 (CZTS) solar cells that use a nonporous n-type-TiO2 material as a window. The advantageous Spike-like conformation against recombination at the TiO2/CZTS interface, which is ensured by the band-engineering offset established using TiO2 material, is discussed. The influence of the geometrical and physical parameters on the device fundamental figures of merit is assessed. Besides, the degradation effect linked to both deep and tail states situated in the gap of the materials, and the effective working temperature, are taken into account. The results reveal that the actual defect type (donor or neutral) at the Cu2ZnSnS4 layer has a harsh influence on the device performance. This is attributed to the raised Shockley–Read–Hall (SRH) recombination highlighted by investigating the variation of the carrier density along the absorber layer. A low barrier height at the back contact (ϕbl = 0.1 eV) and a suitable doping level and thickness of both the window (ND = 4 × 1017 cm−3, WTiO2 = 0.02 µm) and the absorber (NA = 6.5 × 1016 cm−3, WCZTS = 3.2 µm) layers could efficiently improve the device performance.

Simulation of Hetero-junction (GaInP/GaAs) Solar Cell Using AMPS-1D

Photovoltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP / GaAs configuration for p/n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.

Effect of Multijunction Approach on Electrical Measurements of Silicon and Germanium Alloy Based Thin-Film Solar Cell Using AMPS-1D

Multijunction solar cells designed from silicon (Si)-germanium (Ge) alloy based semiconductor materials exhibit high theoretical efficiencies (19.6%) compared to the single junction one. The modeling calculations for all solar cells are done by AMPS 1D simulator. The structure of multi-junction i-layer is designed using heterolayers, starting from pure crystalline Si and increase of Ge mole fraction by 25% until pure Ge layer is reached. The top layer has the largest band gap, while the bottom layer has the smallest bandgap. This design allows less energetic photons to pass through the upper layer(s) and be absorbed by the layer below, which increases the overall efficiency of the solar cell. Material parameters required to model the absorber layers are calculated and incorporated in the AMPS 1D simulator for optimizing of solar cell parameter values. Simulation results show that considerable efficiency enhancement can be obtained from the addition of the multi-junction layer.

Towards Ultra Thin and High Efficiency ZnxCd1-xS/CdTe Solar Cell by AMPS 1D

The main motivation of this work was to obtain high efficiency at reduced CdTe absorber layer thickness and replacing ZnxCd1-xS as window layer in conventional CdS/CdTe solar cells. The conventional CdTe baseline case was the starting point of this investigation to analyze ultra thin and high efficiency ZnxCd1-xS/CdTe solar cell for optimal value of x. The initial step of the analysis was to decrease the CdTe absorber layer to the extreme limit of 1 µm and at this thickness the proposed cell has shown satisfactory level of efficiencies. The ultimate step was to insert a suitable back surface field (BSF) with As2Te3 to reduce the back contact barrier height and back surface recombination loss of the ultra thin cell. All the analysis was done using the widely used simulator Analysis of Microelectronic and Photonic Structures (AMPS 1D). The conversion efficiency of 18.02% (Voc = 0.89 V, Jsc = 25.34 mA/cm2, FF = 0.78) without BSF and an efficiency of 20.3% (Voc = 0.93 V, Jsc = 25.97 mA/cm2, FF = 0.825) with As2Te3 BSF were achieved for the proposed cells from 1 µm and 0.6 µm CdTe absorber layer respectively. Moreover, the normalized efficiency of the proposed ultra thin cells linearly decreased with the increasing operating temperature at the gradient of -0.35%/°C, which indicates better stability of the ultra thin cells.

Modeling of Tandem Solar Cell a-Si/a-SiGe using AMPS-1D Program

Modeling of thin-film silicon solar cell requires taking, the electronic structure and opto-electronic properties of the different amorphous layers into account. However, one of the programs which are convivial for this application is AMPS-1D.In this work, We have performed a Computer modeling of a-Si:H/a-SiGe:H tandem solar cells with p-i-n/p-i-n configuration using AMPS 1D.Initially, we have investigated the influence of the window layer thickness doped p in the efficiency of the amorphous silicon solar cell used as a top cell; however we have analyzed this effect more particularly in the density of currents and quantum efficiency. Also, we have proved the interest of the choice of a-SiC as window layer instead of a-Si material. Secondly, we have modeled a-SiGe solar cell used as bottom cell in tandem configuration, we have also investigated the problem of the interface between materials constituting the solar cell, especially the interface a-SiC/a-SiGe.By a suitable choice of the tunnel junction, we have successfully modelled the Tandem a-Si/a-SiGe solar cell, and the simulation results demonstrate the performances boost of the cell comparing to single junction. The results obtained from simulation give a good agreement with experimental results.