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Article
1 - Improved efficiency of a SiGe thin film solar cell structure using CNT charge collector layerJournal of Theoretical and Applied Physics , Issue 1 , Year , Autumn 2022In this study, a SiGe (Si(1-X) GeX x=0.1) thin film solar cell structure based on the carbon nanotube charge collector (CNT) is investigated. The addition of the carbon nanotube layer to cell structure has been proven to change aspects of its physical characteristics, s MoreIn this study, a SiGe (Si(1-X) GeX x=0.1) thin film solar cell structure based on the carbon nanotube charge collector (CNT) is investigated. The addition of the carbon nanotube layer to cell structure has been proven to change aspects of its physical characteristics, specifically the efficiency of the solar cell. This means that CNT can have a significant impact on structure. The efficiency of suggested structure is 27.72%, which is higher than conventional structures without CNT layer. We optimize this structure by varying the cell layers thickness and calculating the ratio of the top metal contact to the total cell width. Furthermore, the performance of this cell is considering in present of two types of CNT layers with sheet resistances of 128Ω/□ and 76Ω/□. According to numerical simulation CNT layer with 128 Ω/□ sheet resistance has better performance parameters. Finally, the number of metal electrodes above the cell is optimized due to the shading effect and we show that the contact distance in the presence of CNT layer can be increased up to 1000 μm. The cell efficiency after this optimization reaches 30.9%. Manuscript profile -
Article
2 - A Proposal for a New Method of Modeling of the Quantum Dot Semiconductor Optical AmplifiersJournal of Optoelectronical Nanostructures , Issue 4 , Year , Autumn 2019With the advancement of nanoscale semiconductor technology,
semiconductor optical amplifiers are used to amplify and process all-optical signals. In
this paper, with the aim of calculating the gain of quantum dot semiconductor optical
amplifier (QD-SOA), MoreWith the advancement of nanoscale semiconductor technology,
semiconductor optical amplifiers are used to amplify and process all-optical signals. In
this paper, with the aim of calculating the gain of quantum dot semiconductor optical
amplifier (QD-SOA), two groups of rate equations and the optical signal propagating
equation are used in the active layer of the device. For this purpose, the related
equations are presented coherently. In our model, the rate equations that are ordinary
differential equations (ODE) are solved by the Runge-Kutta method. The rate equations
are based on the occupation probabilities of the energy levels instead of the carrier
densities. On the other hand, the signal propagating equation is a partial differential
equation (PDE) and is solved by using the SLICE technique. Therefore, a suitable
solution for numerical modeling is presented. Based on the presented method, modeling
is implemented in the MATLAB environment. The modeling results show a remarkable
accuracy of the model. Also, the proposed model is simple and the runtime is too short
in comparison with other similar models. Manuscript profile -
Article
3 - Self-heating effect modeling of a carbon nanotube-based fieldeffect transistor (CNTFET)Journal of Optoelectronical Nanostructures , Issue 1 , Year , Spring 2019We present the design and simulation of a single-walled carbon nanotube
(SWCNT)-based field-effect transistor (FET) using Silvaco TCAD. In this paper, the
self-heating effect modeling of the CNT MOSFET structure is performed and compared
with conventional MoreWe present the design and simulation of a single-walled carbon nanotube
(SWCNT)-based field-effect transistor (FET) using Silvaco TCAD. In this paper, the
self-heating effect modeling of the CNT MOSFET structure is performed and compared
with conventional MOSFET structure having same channel length. The numerical
results are presented to show the self-heating effect on the I–V characteristics of the
CNT MOSFET and conventional MOSFET structures. Results from numerical
simulation show that the maximum temperature rise and the performance degradation of
the CNT MOSFET are quite lower than that of the conventional MOSFET counterpart.
These advantages are contributed by the good electrical and thermal properties of the
SWCNTs. Therefore, SWCNT materials have a high capability for the development of
active devices with low power dissipation and good reliability at high operating
temperature. Manuscript profile -
Article
4 - Improvement of the Drive Current in 5nm Bulk-FinFET Using Process and Device SimulationsJournal of Optoelectronical Nanostructures , Issue 1 , Year , Spring 2020Abstract: We present the optimization of the manufacturing process of the 5nm bulk-
FinFET technology by using the 3D process and device simulations. In this paper, by
simulating the manufacturing processes, we focus on optimizing the manufacturing
proces MoreAbstract: We present the optimization of the manufacturing process of the 5nm bulk-
FinFET technology by using the 3D process and device simulations. In this paper, by
simulating the manufacturing processes, we focus on optimizing the manufacturing
process to improve the drive current of the 5nm FinFET. The improvement of drive
current is one of the most important issues in the FinFETs design. We first investigate
the impact of manufacturing process parameters include gate oxide thickness, type of
the gate oxide, height of fin, and doping of the source and drain region on threshold
voltage, breakdown voltage, and drive current of the transistor. Then, by selecting the
optimal parameters of the manufacturing process, we improve the drive current of the
5nm bulk-FinFET. Manuscript profile -
Article
5 - Improved Perovskite Solar Cell Performance Using Semitransparent CNT LayerJournal of Optoelectronical Nanostructures , Issue 1 , Year , Spring 2023In this paper, the effect of using semi-transparent Carbon
nanotube layer (CNT) on the efficiency of perovskite
solar cell (PSC) is investigated. One of the most
important process in PCS is charge collecting. In this
regard, Carbon nanotubes have the MoreIn this paper, the effect of using semi-transparent Carbon
nanotube layer (CNT) on the efficiency of perovskite
solar cell (PSC) is investigated. One of the most
important process in PCS is charge collecting. In this
regard, Carbon nanotubes have the ability to act as charge
collector layer in solar cell. Carbon nanotubes, due to
suitable optical and electrical properties such as
transparency, high mobility and stability have been
widely used in solar cell structures. In the proposed
structure, we use semi-transparent CNT layer as charge
collector on top of PSC. This layer with low resistance
path for transport charge carriers has increased short
circuit current and other performance parameters of solar
cell. The proposed device structure
ITO/CNT/TiO2/CH3NH3PbI3/Spiro-OMeTAD is
simulated with Silvaco TCAD. The simulation results
show that the efficiency of the perovskite solar cell with
semi-transparent CNT layer is reached 23.59% which is
3.15% higher than simple perovskite solar cell structure
under AM1.5G. Manuscript profile -
Article
6 - Proposal for Modeling of FWM Efficiency of QD-SOA Based on the Pump/Probe Measurement TechniqueJournal of Optoelectronical Nanostructures , Issue 5 , Year , Winter 2020In this paper, we propose a numerical model for Four-Wave Mixing (FWM)
efficiency in quantum dot semiconductor optical amplifiers (QD-SOAs). Despite the
complexities of the equations governing the QD-SOAs, simple models with short
computational time are e MoreIn this paper, we propose a numerical model for Four-Wave Mixing (FWM)
efficiency in quantum dot semiconductor optical amplifiers (QD-SOAs). Despite the
complexities of the equations governing the QD-SOAs, simple models with short
computational time are essential to analyze and design them. We present equations of
the QD-SOAs coherently and calculate FWM efficiency in the QD-SOA using the
pump/probe technique. In this model, the rate equations take into account the
occupation probabilities of each level instead of the carrier of densities. Moreover, the
transfer matrix based on the pump/probe measurement technique is solved in two
dimensions, space and time, using the Slice technique. The described model is
implemented in the MATLAB environment. The proposed model is simpler than similar
models and has a shorter computational time than them Manuscript profile -
Article
7 - A Carbon Nanotube (CNT)-based SiGe Thin Film Solar Cell StructureJournal of Optoelectronical Nanostructures , Issue 1 , Year , Spring 2021در این مقاله ، ساختاری از سلول خورشیدی فیلم نازک SiGe بر اساس
نانولوله کربنی (CNT) ارائه شده است. ما طراحی و شبیه سازی دستگاه را با استفاده از
Silvaco TCAD ارائه می دهیم. مدل سازی ساختار سلول خورشیدی فیلم نازک SiGe مبتنی بر CNT
انجام شده و سپس با ساختار سلول خورشیدی فیلم نازک SiGe مقایسه می شود.
نتایج حاصل از شبیه سازی عددی نشان می دهد که سلول خورشیدی فیلم نازک SiGe مبتنی بر CNT
دارای پارامترهای بهتری مانند جریان اتصال کوتاه ، ولتاژ مدار باز ، ضریب پر کردن ،
حداکثر توان و کارایی در مقایسه با ساختارهای قبلی است.
نتایج شبیه سازی همچنین ثابت می کند که بازده 40.36٪ افزایش می یابد. Manuscript profile