Tunnel Junctions for III-V Multijunction Solar Cells Review
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Wide Band Gap Materials: Revolution in Automotive Power Electronics
20169052 16mm Wide Band Gap Materials: Revolution in Automotive Power Electronics Luca Bartolomeo 1) Luigi Abbatelli 2) Michele Macauda 2) Filippo Di Giovanni 2) Giuseppe Catalisano 2) Miroslav Ryzek 3) Daniel Kohout 3) 1) STMicroelectronics Japan, Shinagawa INTERCITY Tower A, 2-15-1, Konan, Minato-ku, 108-6017 Tokyo, Japan (E-mail: [email protected]) 2) STMicroelectronics , Italy 3) STMicroelectronics , Czech Republic ④④④ ④④④ Presented at the EVTeC and APE Japan on May 26, 2016 ABSTRACT : The number of Electric and Hybrid vehicles on the roads is increasing year over year. The role of power electronics is of paramount importance to improve their efficiency, keeping lighter and smaller systems. In this paper, the authors will specifically cover the use of Wide Band Gap (WBG) materials in Electric and Hybrid vehicles. It will be shown how SiC MOSFETs bring significant benefits compared to standard IGBTs silicon technology, in both efficiency and form factor. Comparison of the main electrical characteristics, between SiC-based and IGBT module, were simulated and validated by experimental tests in a real automotive environment. KEY WORDS : SiC, Wide Band Gap, IGBT, Power Module 1. INTRODUCTION When considering power transistors in the high voltage range Nowadays, an increased efficiency demand is required in (above 600V), SiC MOSFETs are an excellent alternative to the power electronics applications to have lighter and smaller standard silicon devices: they guarantee lower RON*Area values systems and to improve the range of new Electric (EV) and compared to the latest silicon-based Super-Junction MOSFETs, Hybrid vehicles (HEV). There is an on-going revolution in the especially in high temperature environment (1). -
A HISTORY of the SOLAR CELL, in PATENTS Karthik Kumar, Ph.D
A HISTORY OF THE SOLAR CELL, IN PATENTS Karthik Kumar, Ph.D., Finnegan, Henderson, Farabow, Garrett & Dunner, LLP 901 New York Avenue, N.W., Washington, D.C. 20001 [email protected] Member, Artificial Intelligence & Other Emerging Technologies Committee Intellectual Property Owners Association 1501 M St. N.W., Suite 1150, Washington, D.C. 20005 [email protected] Introduction Solar cell technology has seen exponential growth over the last two decades. It has evolved from serving small-scale niche applications to being considered a mainstream energy source. For example, worldwide solar photovoltaic capacity had grown to 512 Gigawatts by the end of 2018 (representing 27% growth from 2017)1. In 1956, solar panels cost roughly $300 per watt. By 1975, that figure had dropped to just over $100 a watt. Today, a solar panel can cost as little as $0.50 a watt. Several countries are edging towards double-digit contribution to their electricity needs from solar technology, a trend that by most accounts is forecast to continue into the foreseeable future. This exponential adoption has been made possible by 180 years of continuing technological innovation in this industry. Aided by patent protection, this centuries-long technological innovation has steadily improved solar energy conversion efficiency while lowering volume production costs. That history is also littered with the names of some of the foremost scientists and engineers to walk this earth. In this article, we review that history, as captured in the patents filed contemporaneously with the technological innovation. 1 Wiki-Solar, Utility-scale solar in 2018: Still growing thanks to Australia and other later entrants, https://wiki-solar.org/library/public/190314_Utility-scale_solar_in_2018.pdf (Mar. -
IEEE Spectrum Gaas
Proof #4 COLOR 8/5/08 @ 5:15 pm BP BEYOND SILICON’S ELEMENTAL LOGICIN THE QUEST FOR SPEED, KEY PARTS OF MICRO- PROCESSORS MAY SOON BE MADE OF GALLIUM ARSENIDE OR OTHER “III-V” SEMICONDUCTORS BY PEIDE D. YE he first general-purpose lithography, billions of them are routinely microprocessor, the Intel 8080, constructed en masse on the surface of a sili- released in 1974, could execute con wafer. about half a million instructions As these transistors got smaller over the T per second. At the time, that years, more could fit on a chip without rais- seemed pretty zippy. ing its overall cost. They also gained the abil- Today the 8080’s most advanced descen- ity to turn on and off at increasingly rapid dant operates 100 000 times as fast. This phe- rates, allowing microprocessors to hum along nomenal progress is a direct result of the semi- at ever-higher speeds. ALL CHRISTIEARTWORK: BRYAN DESIGN conductor industry’s ability to reduce the size But shrinking MOSFETs much beyond their of a microprocessor’s fundamental building current size—a few tens of nanometers—will be blocks—its many metal-oxide-semiconductor a herculean challenge. Indeed, at some point in field-effect transistors (MOSFETs), which act the next several years, it may become impossi- as tiny switches. Through the magic of photo- ble to make them more minuscule, for reasons WWW.SPECTRUM.IEEE.ORG SEPTEMBER 2008 • IEEE SPECTRUM • INT 39 TOMIC-LAYER DEPOSITION provides one means for coating a semiconductor wafer with a high-k aluminum oxide insulator. The Abenefit of this technique is that it offers atomic-scale control of the coating thickness without requiring elaborate equipment. -
Neutron Transmutation Doping of Silicon at Research Reactors
Silicon at Research Silicon Reactors Neutron Transmutation Doping of Doping Neutron Transmutation IAEA-TECDOC-1681 IAEA-TECDOC-1681 n NEUTRON TRANSMUTATION DOPING OF SILICON AT RESEARCH REACTORS 130010–2 VIENNA ISSN 1011–4289 ISBN 978–92–0– INTERNATIONAL ATOMIC AGENCY ENERGY ATOMIC INTERNATIONAL Neutron Transmutation Doping of Silicon at Research Reactors The following States are Members of the International Atomic Energy Agency: AFGHANISTAN GHANA NIGERIA ALBANIA GREECE NORWAY ALGERIA GUATEMALA OMAN ANGOLA HAITI PAKISTAN ARGENTINA HOLY SEE PALAU ARMENIA HONDURAS PANAMA AUSTRALIA HUNGARY PAPUA NEW GUINEA AUSTRIA ICELAND PARAGUAY AZERBAIJAN INDIA PERU BAHRAIN INDONESIA PHILIPPINES BANGLADESH IRAN, ISLAMIC REPUBLIC OF POLAND BELARUS IRAQ PORTUGAL IRELAND BELGIUM QATAR ISRAEL BELIZE REPUBLIC OF MOLDOVA BENIN ITALY ROMANIA BOLIVIA JAMAICA RUSSIAN FEDERATION BOSNIA AND HERZEGOVINA JAPAN SAUDI ARABIA BOTSWANA JORDAN SENEGAL BRAZIL KAZAKHSTAN SERBIA BULGARIA KENYA SEYCHELLES BURKINA FASO KOREA, REPUBLIC OF SIERRA LEONE BURUNDI KUWAIT SINGAPORE CAMBODIA KYRGYZSTAN CAMEROON LAO PEOPLES DEMOCRATIC SLOVAKIA CANADA REPUBLIC SLOVENIA CENTRAL AFRICAN LATVIA SOUTH AFRICA REPUBLIC LEBANON SPAIN CHAD LESOTHO SRI LANKA CHILE LIBERIA SUDAN CHINA LIBYA SWEDEN COLOMBIA LIECHTENSTEIN SWITZERLAND CONGO LITHUANIA SYRIAN ARAB REPUBLIC COSTA RICA LUXEMBOURG TAJIKISTAN CÔTE DIVOIRE MADAGASCAR THAILAND CROATIA MALAWI THE FORMER YUGOSLAV CUBA MALAYSIA REPUBLIC OF MACEDONIA CYPRUS MALI TUNISIA CZECH REPUBLIC MALTA TURKEY DEMOCRATIC REPUBLIC MARSHALL ISLANDS UGANDA -
Towards Direct-Gap Silicon Phases by the Inverse Band Structure Design Approach
Towards Direct-Gap Silicon Phases by the Inverse Band Structure Design Approach H. J. Xiang1,2*, Bing Huang2, Erjun Kan3, Su-Huai Wei2, X. G. Gong1 1 Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433, P. R. China 2National Renewable Energy Laboratory, Golden, Colorado 80401, USA 3Department of Applied Physics, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, People’s Republic of China e-mail: [email protected] Abstract Diamond silicon (Si) is the leading material in current solar cell market. However, diamond Si is an indirect band gap semiconductor with a large energy difference (2.4 eV) between the direct gap and the indirect gap, which makes it an inefficient absorber of light. In this work, we develop a novel inverse-band structure design approach based on the particle swarming optimization algorithm to predict the metastable Si phases with better optical properties than diamond Si. Using our new method, we predict a cubic Si20 phase with quasi- direct gaps of 1.55 eV, which is a promising candidate for making thin-film solar cells. PACS: 71.20.-b,42.79.Ek,78.20.Ci,88.40.jj 1 Due to the high stability, high abundance, and the existence of an excellent compatible oxide (SiO2), Si is the leading material of microelectronic devices. Currently, the majority of solar cells fabricated to date have also been based on diamond Si in monocrystalline or large- grained polycrystalline form [1]. There are mainly two reasons for this: First, Si is the second most abundant element in the earth's crust; Second, the Si based photovoltaics (PV) industry could benefit from the successful Si based microelectronics industry. -
Modeling Techniques for Multijunction Solar Cells Meghan N
NUSOD 2018 Modeling Techniques for Multijunction Solar Cells Meghan N. Beattie Karin Hinzer Matthew M. Wilkins SUNLAB, Centre for Research in SUNLAB, Centre for Research in SUNLAB, Centre for Research in Photonics Photonics Photonics University of Ottawa University of Ottawa University of Ottawa Ottawa, Canada Ottawa, Canada Ottawa, Canada [email protected] Christopher E. Valdivia SUNLAB, Centre for Research in Photonics University of Ottawa Ottawa, Canada Abstract—Multi-junction solar cell efficiencies far exceed density of defects at the interface [4]. Many of these defects those attainable with silicon photovoltaics. Recently, this propagate towards the surface, resulting in threading technology has been applied to photonic power converters with dislocations that inhibit minority carrier collection [3] In this conversion efficiencies higher than 65%. These devices operate research, we are investigating the use of a voided germanium well in part because of luminescent coupling that occurs in the interface layer to intercept dislocations before they reach the multijunction device. We present modeling results to explain surface, enabling epitaxial growth of high quality Ge, IV how this boosts device efficiencies by approximately 70 mV per (e.g. SiGeSn), and III-V (e.g. InGaAs, InGaP) junction in GaAs devices. Luminescent coupling also increases semiconductors on Si substrates. efficiency in devices with four more junctions, however, the high cost of materials remains a barrier to their widespread By modelling multijunction solar cell designs on Si use. Substantial cost reduction could be achieved by replacing substrates, we investigate the impact of threading the germanium substrate with a less expensive alternative: dislocations on device performance. With highly doped Si, silicon. -
CSE- Module-3: SEMICONDUCTOR LIGHT EMITTING DIODE :LED (5Lectures)
CSE-Module- 3:LED PHYSICS CSE- Module-3: SEMICONDUCTOR LIGHT EMITTING DIODE :LED (5Lectures) Light Emitting Diodes (LEDs) Light Emitting Diodes (LEDs) are semiconductors p-n junction operating under proper forward biased conditions and are capable of emitting external spontaneous radiations in the visible range (370 nm to 770 nm) or the nearby ultraviolet and infrared regions of the electromagnetic spectrum General Structure LEDs are special diodes that emit light when connected in a circuit. They are frequently used as “pilot light” in electronic appliances in to indicate whether the circuit is closed or not. The structure and circuit symbol is shown in Fig.1. The two wires extending below the LED epoxy enclose or the “bulb” indicate how the LED should be connected into a circuit or not. The negative side of the LED is indicated in two ways (1) by the flat side of the bulb and (2) by the shorter of the two wires extending from the LED. The negative lead should be connected to the negative terminal of a battery. LEDs operate at relative low voltage between 1 and 4 volts, and draw current between 10 and 40 milliamperes. Voltages and Fig.-1 : Structure of LED current substantially above these values can melt a LED chip. The most important part of a light emitting diode (LED) is the semiconductor chip located in the centre of the bulb and is attached to the 1 CSE-Module- 3:LED top of the anvil. The chip has two regions separated by a junction. The p- region is dominated by positive electric charges, and the n-region is dominated by negative electric charges. -
Demonstrating Solar Conversion Using Natural Dye Sensitizers
Demonstrating Solar Conversion Using Natural Dye Sensitizers Subject Area(s) Science & Technology, Physical Science, Environmental Science, Physics, Biology, and Chemistry Associated Unit Renewable Energy Lesson Title Dye Sensitized Solar Cell (DSSC) Grade Level (11th-12th) Time Required 3 hours / 3 day lab Summary Students will analyze the use of solar energy, explore future trends in solar, and demonstrate electron transfer by constructing a dye-sensitized solar cell using vegetable and fruit products. Students will analyze how energy is measured and test power output from their solar cells. Engineering Connection and Tennessee Careers An important aspect of building solar technology is the study of the type of materials that conduct electricity and understanding the reason why they conduct electricity. Within the TN-SCORE program Chemical Engineers, Biologist, Physicist, and Chemists are working together to provide innovative ways for sustainable improvements in solar energy technologies. The lab for this lesson is designed so that students apply their scientific discoveries in solar design. Students will explore how designing efficient and cost effective solar panels and fuel cells will respond to the social, political, and economic needs of society today. Teachers can use the Metropolitan Policy Program Guide “Sizing The Clean Economy: State of Tennessee” for information on Clean Economy Job Growth, TN Clean Economy Profile, and Clean Economy Employers. www.brookings.edu/metro/clean_economy.aspx Keywords Photosynthesis, power, electricity, renewable energy, solar cells, photovoltaic (PV), chlorophyll, dye sensitized solar cells (DSSC) Page 1 of 10 Next Generation Science Standards HS.ESS-Climate Change and Human Sustainability HS.PS-Chemical Reactions, Energy, Forces and Energy, and Nuclear Processes HS.ETS-Engineering Design HS.ETS-ETSS- Links Among Engineering, Technology, Science, and Society Pre-Requisite Knowledge Vocabulary: Catalyst- A substance that increases the rate of reaction without being consumed in the reaction. -
Thin Film Cdte Photovoltaics and the U.S. Energy Transition in 2020
Thin Film CdTe Photovoltaics and the U.S. Energy Transition in 2020 QESST Engineering Research Center Arizona State University Massachusetts Institute of Technology Clark A. Miller, Ian Marius Peters, Shivam Zaveri TABLE OF CONTENTS Executive Summary .............................................................................................. 9 I - The Place of Solar Energy in a Low-Carbon Energy Transition ...................... 12 A - The Contribution of Photovoltaic Solar Energy to the Energy Transition .. 14 B - Transition Scenarios .................................................................................. 16 I.B.1 - Decarbonizing California ................................................................... 16 I.B.2 - 100% Renewables in Australia ......................................................... 17 II - PV Performance ............................................................................................. 20 A - Technology Roadmap ................................................................................. 21 II.A.1 - Efficiency ........................................................................................... 22 II.A.2 - Module Cost ...................................................................................... 27 II.A.3 - Levelized Cost of Energy (LCOE) ....................................................... 29 II.A.4 - Energy Payback Time ........................................................................ 32 B - Hot and Humid Climates ........................................................................... -
The Band Gap of Silicon
Norton 0 The Band Gap of Silicon Matthew Norton, Erin Stefanik, Ryan Allured, and Drew Sulski Norton 1 Abstract This experiment was designed to find the band gap of silicon as well as the charge of an electron. A transistor was heated to various temperatures using a hot plate. The resistance was measured over the resistor and transistor in the circuit. In performing this experiment, it was found that the band gap of silicon was (1.10 ± 0.08) eV. In performing this experiment, it was also found that the charge of an electron was (1.77 ± 0.20) × 10 −19 C. Introduction When a substance is placed under the influence of an electric field, it can portray insulating, semi-conducting, semi-metallic, or metallic properties. Every crystalline structure has electrons that occupy energy bands. In a semiconductor, there is a gap in energy between valence band and the bottom of the conduction band. There are no allowed energy states for the electron within the energy gap. At absolute zero, all the electrons have energies within the valence band and the material it is insulating. As the temperature increases electrons gain enough energy to occupy the energy levels in the conduction band. The current through a transistor is given by the equation, qV I= I e kT − 1 0 (1) where I0 is the maximum current for a large reverse bias voltage, q is the charge of the electron, k is the Boltzmann constant, and T is the temperature in Kelvin. As long as V is not too large, the current depends only on the number of minority carriers in the conduction band and the rate at which they diffuse. -
Fabrication Procedure of Dye-Sensitized Solar Cells
Fabrication procedure of dye-sensitized solar cells K.Takechi, R.Muszynski and P.V.Kamat Materials - ITO(Indium doped Tin Oxide) glass (2 x 2 cm, 2 slides for 1 cell) - Dye (Eosin Y, Eosin B, etc.) - Ethanol - TiO2 paste ¾ Suspend 3.5g of TiO2 nano-powder P25 in 15ml of ethanol. ¾ Sonicate it at least for 30 min. ¾ Add 0.5ml of titanium(IV) tetraisopropoxide into the suspension. ¾ Mix until the suspension is uniform. (D.S. Zhang, T. Yoshida, T. Oekermann, K. Furuta, H. Minoura, Adv. Functional Mater., 16, 1228(2006).) - Spacer ¾ Cut a plastic film (like as Parafilm or Scotch tape) having dimensions of 1.5 cm by 2 cm. ¾ Make a hole(s) on the film. 2 cm (Example) 1 cm 1.5 cm Hole 0.6 cm - Liquid electrolyte ¾ 0.5M lithium iodide and 0.05M iodine in acetonitrile. γ-Butyrolactone or 3-methoxypropionitrile is also recommended as a solvent to improve its volatility. - Binder clips (small, 2 pieces for 1 cell) Tools - Hot plate - Pipets - Tweezers - Spatulas - Scotch tape 1. Put Scotch tape on the conducting side of ITO glass. about 10 mm 2. Put TiO2 paste and flatten it with a razor blade on the same side of the ITO glass. 3. Put this electrode on top of a hot plate and heat it at approximately 150 °C for 10 min. 4. Prepare a dye solution. (Ex. 20mL of 1 mM eosin Y in ethanol) Eosin Y Eosin B Eosin B in ethanol (Mw=691.85) (Mw=624.06) 5. Dip the TiO2 electrode into the dye solution for 10 min. -
Efficient Er/O Doped Silicon Light-Emitting Diodes at Communication Wavelength by Deep Cooling
Efficient Er/O Doped Silicon Light-Emitting Diodes at Communication Wavelength by Deep Cooling Huimin Wen1,#, Jiajing He1,#, Jin Hong2,#, Fangyu Yue2* & Yaping Dan1* 1University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai, 200240, China. 2Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University, Shanghai, 200241, China. #These authors contributed equally * To whom correspondence should be addressed: [email protected], [email protected] Abstract A silicon light source at communication wavelength is the bottleneck for developing monolithically integrated silicon photonics. Doping silicon with erbium ions was believed to be one of the most promising approaches but suffers from the aggregation of erbium ions that are efficient non-radiative centers, formed during the standard rapid thermal treatment. Here, we apply a deep cooling process following the high- temperature annealing to suppress the aggregation of erbium ions by flushing with Helium gas cooled in liquid nitrogen. The resultant light emitting efficiency is increased to a record 14% at room temperature, two orders of magnitude higher than the sample treated by the standard rapid thermal annealing. The deep-cooling-processed Si samples were further made into light-emitting diodes. Bright electroluminescence with a spectral peak at 1.54 µm from the silicon-based diodes was also observed at room temperature. With these results, it is promising to develop efficient silicon lasers at communication wavelength for the monolithically integrated silicon photonics. The monolithic integration of fiber optics with complementary metal-oxide- semiconductor (CMOS) integrated circuits will significantly speed up the computing and data transmission of current communication networks.1-3 This technology requires efficient silicon-based lasers at communication wavelengths.4, 5 Unfortunately, silicon is an indirect bandgap semiconductor and cannot emit light at communication wavelengths.