Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer

In spite of many efforts to propose new semiconductor materials and sophisticated constructions of solar cells, crystalline silicone remains the main photovoltaic material widely used up to now. There are various methods to enhance the efficiency of silicone solar cells. One of them is to combine si...

Full description

Saved in:
Bibliographic Details
Main Authors: A. B. Gnilenko, Ju. N. Lavrich, S. V. Plaksin
Format: Article
Language:English
Published: Politehperiodika 2015-12-01
Series:Tekhnologiya i Konstruirovanie v Elektronnoi Apparature
Subjects:
Online Access:https://tkea.com.ua/index.php/journal/article/view/261
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849313302716350464
author A. B. Gnilenko
Ju. N. Lavrich
S. V. Plaksin
author_facet A. B. Gnilenko
Ju. N. Lavrich
S. V. Plaksin
author_sort A. B. Gnilenko
collection DOAJ
description In spite of many efforts to propose new semiconductor materials and sophisticated constructions of solar cells, crystalline silicone remains the main photovoltaic material widely used up to now. There are various methods to enhance the efficiency of silicone solar cells. One of them is to combine silicone with an additional semiconductor material with the different bandgap to form a tandem construction. For example, the germanium sub-cell used as the bottom cascade for the silicone sub-cell in the tandem monolithic solar cell makes it possible to utilize the "red" sub-band of solar spectra increasing overall solar cell efficiency. The problem of the 4.2% mismatch in lattice constant between Si and Ge can be resolved in such a case by the use of SiGe buffer layer. In the paper the results of the computer simulation for Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer are presented. In the solar cell under consideration, the step graded Si1-xGex buffer layer is located between the top silicone and the bottom germanium cascades to reduce the threading dislocation density in mismatched materials. The cascades are commutated by the use of the germanium tunnel diode between the bottom sub-cell and the buffer layer. For the solar cell modeling, the physically-based device simulator ATLAS of Silvaco TCAD software is employed to predict the electrical behavior of the semiconductor structure and to provide a deep insight into the internal physical processes. The voltage-current characteristic, photovoltaic parameters and the distribution of basic physical values are obtained for the investigated tandem solar cell. The influence of layer thicknesses on the photovoltaic parameters is studied. The calculated efficiency of the tandem solar cell reaches 13% which is a quarter more than the efficiency of a simple silicone solar cell with the same constructive parameters and under the same illumination conditions.
format Article
id doaj-art-85e9f2b352c64389bf0d34b63b6a3aa6
institution Kabale University
issn 2225-5818
2309-9992
language English
publishDate 2015-12-01
publisher Politehperiodika
record_format Article
series Tekhnologiya i Konstruirovanie v Elektronnoi Apparature
spelling doaj-art-85e9f2b352c64389bf0d34b63b6a3aa62025-08-20T03:52:48ZengPolitehperiodikaTekhnologiya i Konstruirovanie v Elektronnoi Apparature2225-58182309-99922015-12-015–6283410.15222/TKEA2015.5-6.28261Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layerA. B. Gnilenko0Ju. N. Lavrich1S. V. Plaksin2Oles Honchar Dnipro National University, Dnipro, UkraineInstitute of transport systems and technologies of NAS of Ukraine ("TRANSMAG"), Dnipro, UkraineInstitute of transport systems and technologies of NAS of Ukraine ("TRANSMAG"), Dnipro, UkraineIn spite of many efforts to propose new semiconductor materials and sophisticated constructions of solar cells, crystalline silicone remains the main photovoltaic material widely used up to now. There are various methods to enhance the efficiency of silicone solar cells. One of them is to combine silicone with an additional semiconductor material with the different bandgap to form a tandem construction. For example, the germanium sub-cell used as the bottom cascade for the silicone sub-cell in the tandem monolithic solar cell makes it possible to utilize the "red" sub-band of solar spectra increasing overall solar cell efficiency. The problem of the 4.2% mismatch in lattice constant between Si and Ge can be resolved in such a case by the use of SiGe buffer layer. In the paper the results of the computer simulation for Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer are presented. In the solar cell under consideration, the step graded Si1-xGex buffer layer is located between the top silicone and the bottom germanium cascades to reduce the threading dislocation density in mismatched materials. The cascades are commutated by the use of the germanium tunnel diode between the bottom sub-cell and the buffer layer. For the solar cell modeling, the physically-based device simulator ATLAS of Silvaco TCAD software is employed to predict the electrical behavior of the semiconductor structure and to provide a deep insight into the internal physical processes. The voltage-current characteristic, photovoltaic parameters and the distribution of basic physical values are obtained for the investigated tandem solar cell. The influence of layer thicknesses on the photovoltaic parameters is studied. The calculated efficiency of the tandem solar cell reaches 13% which is a quarter more than the efficiency of a simple silicone solar cell with the same constructive parameters and under the same illumination conditions.https://tkea.com.ua/index.php/journal/article/view/261photovoltaic celltandem solar cellbuffer layersilvaco tcaddrift-diffusion modelvoltage-current characteristicsefficiency
spellingShingle A. B. Gnilenko
Ju. N. Lavrich
S. V. Plaksin
Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
Tekhnologiya i Konstruirovanie v Elektronnoi Apparature
photovoltaic cell
tandem solar cell
buffer layer
silvaco tcad
drift-diffusion model
voltage-current characteristics
efficiency
title Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
title_full Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
title_fullStr Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
title_full_unstemmed Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
title_short Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
title_sort simulating characteristics of si ge tandem monolithic solar cell with si1 xgex buffer layer
topic photovoltaic cell
tandem solar cell
buffer layer
silvaco tcad
drift-diffusion model
voltage-current characteristics
efficiency
url https://tkea.com.ua/index.php/journal/article/view/261
work_keys_str_mv AT abgnilenko simulatingcharacteristicsofsigetandemmonolithicsolarcellwithsi1xgexbufferlayer
AT junlavrich simulatingcharacteristicsofsigetandemmonolithicsolarcellwithsi1xgexbufferlayer
AT svplaksin simulatingcharacteristicsofsigetandemmonolithicsolarcellwithsi1xgexbufferlayer