Crystalline silicon

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Crystalline-silicon solar cells are made of either Poly Silicon (left side) or Mono Silicon (right side). Comparison solar cell poly-Si vs mono-Si.png
Crystalline-silicon solar cells are made of either Poly Silicon (left side) or Mono Silicon (right side).

Crystalline silicon or (c-Si) Is the crystalline forms of silicon, either polycrystalline silicon (poly-Si, consisting of small crystals), or monocrystalline silicon (mono-Si, a continuous crystal). Crystalline silicon is the dominant semiconducting material used in photovoltaic technology for the production of solar cells. These cells are assembled into solar panels as part of a photovoltaic system to generate solar power from sunlight.

Contents

In electronics, crystalline silicon is typically the monocrystalline form of silicon, and is used for producing microchips. This silicon contains much lower impurity levels than those required for solar cells. Production of semiconductor grade silicon involves a chemical purification to produce Hyper-pure Polysilicon, followed by a recrystallization process to grow monocrystalline silicon. The cylindrical boules are then cut into wafers for further processing.

Solar cells made of crystalline silicon are often called conventional, traditional, or first generation solar cells, as they were developed in the 1950s and remained the most common type up to the present time. [1] [2] Because they are produced from 160 to 190  μm thick solar wafers—slices from bulks of solar grade silicon—they are sometimes called wafer-based solar cells.

Solar cells made from c-Si are single-junction cells and are generally more efficient than their rival technologies, which are the second-generation thin-film solar cells, the most important being CdTe, CIGS, and amorphous silicon (a-Si). Amorphous silicon is an allotropic variant of silicon, and amorphous means "without shape" to describe its non-crystalline form. [3] : 29 

Overview

Global PV market by technology in 2021. [4] : 24, 25 

   CdTe (4.1%)
   a-Si (0.1%)
   CIGS (0.8%)
   mono-Si (82%)
   multi-Si (13%)

Classification

The allotropic forms of silicon range from a single crystalline structure to a completely unordered amorphous structure with several intermediate varieties. In addition, each of these different forms can possess several names and even more abbreviations, and often cause confusion to non-experts, especially as some materials and their application as a PV technology are of minor significance, while other materials are of outstanding importance.

PV industry

In photovoltaic industry,materials are commonly grouped into the following two categories:

Generations

Alternatively, different types of solar cells and/or their semiconducting materials can be classified by generations:

  • First generation solar cells are made of crystalline silicon, also called, conventional, traditional, wafer-based solar cells and include monocrystalline (mono-Si) and polycrystalline (multi-Si) semiconducting materials.
  • Second generation solar cells or panels are based on thin-film technology and are of commercially significant importance. These include CdTe, CIGS and amorphous silicon.
  • Third generation solar cells are often labeled as emerging technologies with little or no market significance and include a large range of substances, mostly organic, often using organometallic compounds.

Arguably, multi-junction photovoltaic cells can be classified to neither of these generations. A typical triple junction semiconductor is made of InGaP/(In)GaAs/Ge. [5] [6]

Comparison of technical specifications

CategoriesTechnology η (%) VOC (V) ISC (A) W/m2 t (μm)
Thin-film solar cells
a-Si 11.16.30.0089331
CdTe 16.50.860.029–5
CIGS 20.5–––

Market share

Global Photovoltaics market share by technology 1980-2021. Global photovoltaics market share by technology 1980-2021.svg
Global Photovoltaics market share by technology 1980–2021.

In 2013, conventional crystalline silicon technology dominated worldwide PV production, with multi-Si leading the market ahead of mono-Si, accounting for 54% and 36%, respectively. For the last ten years, worldwide market-share of thin-film technologies stagnated below 18% and currently stand at 9%. In the thin-film market, CdTe leads with an annual production of 2  GW p or 5%, followed by a-Si and CIGS, both around 2%. [3] : 4, 18  Alltime deployed PV capacity of 139 gigawatts (cumulative as of 2013) splits up into 121 GW crystalline silicon (87%) and 18 GW thin-film (13%) technology. [3] : 41 

Efficiency

Conversion Efficiencies of best research solar cells worldwide for various Photovoltaic Technologies since 1976. Best Research-Cell Efficiencies.png
Conversion Efficiencies of best research solar cells worldwide for various Photovoltaic Technologies since 1976.

The conversion efficiency of PV devices describes the energy-ratio of the outgoing electrical power compared to the incoming radiated light. A single solar cells has generally a better, or higher efficiency than an entire solar module. Additionally, lab efficiency is always far superior to that of goods that are sold commercially.

Lab cells

In 2013, record Lab cell efficiency was highest for crystalline silicon. However, multi-silicon is followed closely by cadmium telluride and copper indium gallium selenide solar cells.

  1. 25.6% ------- mono-Si cell
  2. 20.4% -------- multi-Si cell
  3. 21.7% ----------- CIGS cell
  4. 21.5% ----------- CdTe cell

Both-sides-contacted silicon solar cells as of 2021: 26% and possibly above. [7] [8]

Modules

The average commercial crystalline silicon module increased its efficiency from about 12% to 16% over the last ten years. In the same period CdTe-modules improved their efficiency from 9 to 16%. The modules performing best under lab conditions in 2014 were made of monocrystalline silicon. They were 7% above the efficiency of commercially produced modules (23% over 16%) which indicated that the conventional silicon technology still had potential to improve and therefore maintain its leading position. [3] : 6 

Energy costs of manufacture

Crystalline silicon has a high cost in energy because silicon is produced by the reduction of high-grade quartz sand in an electric furnace. The electricity generated for this process may produce greenhouse gas emissions. This coke-fired smelting process occurs at high temperatures of more than 1,000 °C and is very energy intensive, using about 11 kilowatt-hours (kWh) per kilogram of silicon. [9]

The energy requirements of this process per unit of silicon metal produced may be relatively inelastic. But major energy cost reductions per (photovoltaic) product have been made as silicon cells have become more efficient at converting sunlight, larger silicon metal ingots are cut with less waste into thinner wafers, silicon waste from manufacture is recycled, and material costs have reduced. [3] : 29 

Toxicity

With the exception of amorphous silicon, most commercially established PV technologies use toxic heavy metals. CIGS often uses a CdS buffer layer, and the semiconductor material of CdTe-technology itself contains the toxic cadmium (Cd). In the case of crystalline silicon modules, the solder material that joins the copper strings of the cells, it contains about 36% of lead (Pb). Moreover, the paste used for screen printing front and back contacts contains traces of Pb and sometimes Cd as well. It is estimated that about 1,000 metric tonnes of Pb have been used for 100 gigawatts of c-Si solar modules. However, there is no fundamental need for lead in the solder alloy. [10]

Cell technologies

PERC solar cell

Passivated emitter rear contact (PERC) solar cells [11] consist of the addition of an extra layer to the rear-side of a solar cell. This dielectric passive layer acts to reflect unabsorbed light back to the solar cell for a second absorption attempt increasing the solar cell efficiency. [12]

A PERC is created through an additional film deposition and etching process. Etching can be done either by chemical or laser processing. About 80% of solar panels worldwide use the PERC design. [13] Martin Green, Andrew Blakers, Jianhua Zhao and Aihua Wang won the Queen Elizabeth Prize for Engineering in 2023 for development of the PERC solar cell. [14]

HIT solar cell

Schematics of a HIT-cell... HIT cell.jpg
Schematics of a HIT-cell...

A HIT solar cell is composed of a mono thin crystalline silicon wafer surrounded by ultra-thin amorphous silicon layers. [15] The acronym HIT stands for "heterojunction with intrinsic thin layer". HIT cells are produced by the Japanese multinational electronics corporation Panasonic (see also Sanyo § Solar cells and plants). [16] Panasonic and several other groups have reported several advantages of the HIT design over its traditional c-Si counterpart:

1. An intrinsic a-Si layer can act as an effective surface passivation layer for c-Si wafer.

2. The p+/n+ doped a-Si functions as an effective emitter/BSF for the cell.

3. The a-Si layers are deposited at much lower temperature, compared to the processing temperatures for traditional diffused c-Si technology.

4. The HIT cell has a lower temperature coefficient compared to c-Si cell technology.

Owing to all these advantages, this new hetero-junction solar cell is a considered to be a promising low cost alternative to traditional c-Si based solar cells.

Fabrication of HIT cells

The details of the fabrication sequence vary from group to group. Typically in good quality, CZ/FZ grown c-Si wafer (with ~1ms lifetimes) are used as the absorber layer of HIT cells. Using alkaline etchants, such as, NaOH or (CH3)4NOH the (100) surface of the wafer is textured to form the pyramids of 5-10μm height. Next, the wafer is cleaned using peroxide and HF solutions. This is followed by deposition of intrinsic a-Si passivation layer, typically through PECVD or Hot-wire CVD. [17] [18] The silane (SiH4) gas diluted with H2 is used as a precursor. The deposition temperature and pressure is maintained at 200o C and 0.1-1 Torr. Precise control over this step is essential to avoid the formation of defective epitaxial Si. [19]

Cycles of deposition and annealing and H2 plasma treatment are shown to have provided excellent surface passivation. [20] [21] Diborane or Trimethylboron gas mixed with SiH4 is used to deposit p-type a-Si layer, while, Phosphine gas mixed with SiH4 is used to deposit n-type a-Si layer. Direct deposition of doped a-Si layers on c-Si wafer is shown to have very poor passivation properties. [22] This is most likely due to dopant induced defect generation in a-Si layers. [23] Sputtered Indium Tin Oxide (ITO) is commonly used as a transparent conductive oxide (TCO) layer on top of the front and back a-Si layer in bi-facial design, as a-Si has high lateral resistance.

It is generally deposited on the back side as well fully metallized cell to avoid diffusion of back metal and also for impedance matching for the reflected light. [24] The silver/aluminum grid of 50-100μm thick is deposited through stencil printing for the front contact and back contact for bi-facial design. The detailed description of the fabrication process can be found in. [25]

Opto-electrical modeling and characterization of HIT cells

The literature discusses several studies to interpret carrier transport bottlenecks in these cells. Traditional light and dark I-V are extensively studied [26] [27] [28] and are observed to have several non-trivial features, which cannot be explained using the traditional solar cell diode theory. [29] This is because of the presence of hetero-junction between the intrinsic a-Si layer and c-Si wafer which introduces additional complexities to current flow. [26] [30] In addition, there has been significant efforts to characterize this solar cell using C-V, [31] [32] impedance spectroscopy, [31] [33] [34] surface photo-voltage, [35] suns-Voc [36] [37] to produce complementary information.

Further, a number of design improvements, such as, the use of new emitters, [38] bifacial configuration, interdigitated back contact (IBC) configuration [39] bifacial-tandem configuration [40] are actively being pursued.

Mono-silicon

Schematic of allotropic forms of silicon. Schematic of allotropic forms of silcon.svg
Schematic of allotropic forms of silicon.

Monocrystalline silicon (mono c-Si) is a form in which the crystal structure is homogeneous throughout the material; the orientation, lattice parameter, and electronic properties are constant throughout the material. [41] Dopant atoms such as phosphorus and boron are often incorporated into the film to make the silicon n-type or p-type respectively. Monocrystalline silicon is fabricated in the form of silicon wafers, usually by the Czochralski Growth method, and can be quite expensive depending on the radial size of the desired single crystal wafer (around $200 for a 300 mm Si wafer). [41] This monocrystalline material, while useful, is one of the chief expenses associated with producing photovoltaics where approximately 40% of the final price of the product is attributable to the cost of the starting silicon wafer used in cell fabrication. [42]

Polycrystalline silicon

Polycrystalline silicon is composed of many smaller silicon grains of varied crystallographic orientation, typically >1 mm in size. This material can be synthesized easily by allowing liquid silicon to cool using a seed crystal of the desired crystal structure. Additionally, other methods for forming smaller-grained polycrystalline silicon (poly-Si) exist such as high temperature chemical vapor deposition (CVD).

Not classified as Crystalline silicon

These allotropic forms of silicon are not classified as crystalline silicon. They belong to the group of thin-film solar cells.

Amorphous silicon

Amorphous silicon (a-Si) has no long-range periodic order. The application of amorphous silicon to photovoltaics as a standalone material is somewhat limited by its inferior electronic properties. [43] When paired with microcrystalline silicon in tandem and triple-junction solar cells, however, higher efficiency can be attained than with single-junction solar cells. [44] This tandem assembly of solar cells allows one to obtain a thin-film material with a bandgap of around 1.12 eV (the same as single-crystal silicon) compared to the bandgap of amorphous silicon of 1.7-1.8 eV bandgap. Tandem solar cells are then attractive since they can be fabricated with a bandgap similar to single-crystal silicon but with the ease of amorphous silicon.

Nanocrystalline silicon

Nanocrystalline silicon (nc-Si), sometimes also known as microcrystalline silicon (μc-Si), is a form of porous silicon. [45] It is an allotropic form of silicon with paracrystalline structure—is similar to amorphous silicon (a-Si), in that it has an amorphous phase. Where they differ, however, is that nc-Si has small grains of crystalline silicon within the amorphous phase. This is in contrast to polycrystalline silicon (poly-Si) which consists solely of crystalline silicon grains, separated by grain boundaries. The difference comes solely from the grain size of the crystalline grains. Most materials with grains in the micrometre range are actually fine-grained polysilicon, so nanocrystalline silicon is a better term. The term Nanocrystalline silicon refers to a range of materials around the transition region from amorphous to microcrystalline phase in the silicon thin film.

Protocrystalline silicon

Protocrystalline silicon has a higher efficiency than amorphous silicon (a-Si) and it has also been shown to improve stability, but not eliminate it. [46] [47] A Protocrystalline phase is a distinct phase occurring during crystal growth which evolves into a microcrystalline form.

Protocrystalline Si also has a relatively low absorption near the band gap owing to its more ordered crystalline structure. Thus, protocrystalline and amorphous silicon can be combined in a tandem solar cell where the top layer of thin protocrystalline silicon absorbs short-wavelength light whereas the longer wavelengths are absorbed by the underlying a-Si substrate.

Transformation of amorphous into crystalline silicon

Amorphous silicon can be transformed to crystalline silicon using well-understood and widely implemented high-temperature annealing processes. The typical method used in industry requires high-temperature compatible materials, such as special high temperature glass that is expensive to produce. However, there are many applications for which this is an inherently unattractive production method.

Low temperature induced crystallization

Flexible solar cells have been a topic of interest for less conspicuous-integrated power generation than solar power farms. These modules may be placed in areas where traditional cells would not be feasible, such as wrapped around a telephone pole or cell phone tower. In this application, a photovoltaic material may be applied to a flexible substrate, often a polymer. Such substrates cannot survive the high temperatures experienced during traditional annealing. Instead, novel methods of crystallizing the silicon without disturbing the underlying substrate have been studied extensively. Aluminum-induced crystallization (AIC) and local laser crystallization are common in the literature, however not extensively used in industry.

In both of these methods, amorphous silicon is grown using traditional techniques such as plasma-enhanced chemical vapor deposition (PECVD). The crystallization methods diverge during post-deposition processing. In aluminum-induced crystallization, a thin layer of aluminum (50 nm or less) is deposited by physical vapor deposition onto the surface of the amorphous silicon. This stack of material is then annealed at a relatively low temperature between 140 °C and 200 °C in a vacuum. The aluminum that diffuses into the amorphous silicon is believed to weaken the hydrogen bonds present, allowing crystal nucleation and growth. [48] Experiments have shown that polycrystalline silicon with grains on the order of 0.2 – 0.3 μm can be produced at temperatures as low as 150 °C. The volume fraction of the film that is crystallized is dependent on the length of the annealing process. [48]

Aluminum-induced crystallization produces polycrystalline silicon with suitable crystallographic and electronic properties that make it a candidate for producing polycrystalline thin films for photovoltaics. [48] AIC can be used to generate crystalline silicon nanowires and other nano-scale structures.

Another method of achieving the same result is the use of a laser to heat the silicon locally without heating the underlying substrate beyond some upper-temperature limit. An excimer laser or, alternatively, green lasers such as a frequency-doubled Nd:YAG laser is used to heat the amorphous silicon, supplying the energy necessary to nucleate grain growth. The laser fluence must be carefully controlled in order to induce crystallization without causing widespread melting. Crystallization of the film occurs as a very small portion of the silicon film is melted and allowed to cool. Ideally, the laser should melt the silicon film through its entire thickness, but not damage the substrate. Toward this end, a layer of silicon dioxide is sometimes added to act as a thermal barrier. [49] This allows the use of substrates that cannot be exposed to the high temperatures of standard annealing, polymers for instance. Polymer-backed solar cells are of interest for seamlessly integrated power production schemes that involve placing photovoltaics on everyday surfaces.

A third method for crystallizing amorphous silicon is the use of a thermal plasma jet. This strategy is an attempt to alleviate some of the problems associated with laser processing – namely the small region of crystallization and the high cost of the process on a production scale. The plasma torch is a simple piece of equipment that is used to anneal the amorphous silicon thermally. Compared to the laser method, this technique is simpler and more cost-effective. [50] Plasma torch annealing is attractive because the process parameters and equipment dimensions can be changed easily to yield varying levels of performance. A high level of crystallization (~90%) can be obtained with this method. Disadvantages include difficulty achieving uniformity in the crystallization of the film. While this method is applied frequently to silicon on a glass substrate, processing temperatures may be too high for polymers.

See also

Related Research Articles

<span class="mw-page-title-main">Nanocrystalline silicon</span>

Nanocrystalline silicon (nc-Si), sometimes also known as microcrystalline silicon (μc-Si), is a form of porous silicon. It is an allotropic form of silicon with paracrystalline structure—is similar to amorphous silicon (a-Si), in that it has an amorphous phase. Where they differ, however, is that nc-Si has small grains of crystalline silicon within the amorphous phase. This is in contrast to polycrystalline silicon (poly-Si) which consists solely of crystalline silicon grains, separated by grain boundaries. The difference comes solely from the grain size of the crystalline grains. Most materials with grains in the micrometre range are actually fine-grained polysilicon, so nanocrystalline silicon is a better term. The term Nanocrystalline silicon refers to a range of materials around the transition region from amorphous to microcrystalline phase in the silicon thin film. The crystalline volume fraction is another criterion to describe the materials in this transition zone.

<span class="mw-page-title-main">Epitaxy</span> Crystal growth process relative to the substrate

Epitaxy refers to a type of crystal growth or material deposition in which new crystalline layers are formed with one or more well-defined orientations with respect to the crystalline seed layer. The deposited crystalline film is called an epitaxial film or epitaxial layer. The relative orientation(s) of the epitaxial layer to the seed layer is defined in terms of the orientation of the crystal lattice of each material. For most epitaxial growths, the new layer is usually crystalline and each crystallographic domain of the overlayer must have a well-defined orientation relative to the substrate crystal structure. Epitaxy can involve single-crystal structures, although grain-to-grain epitaxy has been observed in granular films. For most technological applications, single-domain epitaxy, which is the growth of an overlayer crystal with one well-defined orientation with respect to the substrate crystal, is preferred. Epitaxy can also play an important role while growing superlattice structures.

<span class="mw-page-title-main">Photovoltaics</span> Method to produce electricity from solar radiation

Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially used for electricity generation and as photosensors.

A heterojunction is an interface between two layers or regions of dissimilar semiconductors. These semiconducting materials have unequal band gaps as opposed to a homojunction. It is often advantageous to engineer the electronic energy bands in many solid-state device applications, including semiconductor lasers, solar cells and transistors. The combination of multiple heterojunctions together in a device is called a heterostructure, although the two terms are commonly used interchangeably. The requirement that each material be a semiconductor with unequal band gaps is somewhat loose, especially on small length scales, where electronic properties depend on spatial properties. A more modern definition of heterojunction is the interface between any two solid-state materials, including crystalline and amorphous structures of metallic, insulating, fast ion conductor and semiconducting materials.

An epitaxial wafer is a wafer of semiconducting material made by epitaxial growth (epitaxy) for use in photonics, microelectronics, spintronics, or photovoltaics. The epi layer may be the same material as the substrate, typically monocrystaline silicon, or it may be a silicon dioxide (SoI) or a more exotic material with specific desirable qualities. The purpose of epitaxy is to perfect the crystal structure over the bare substrate below and improve the wafer surface's electrical characteristics, making it suitable for highly complex microprocessors and memory devices.

<span class="mw-page-title-main">Solar cell</span> Photodiode used to produce power from light on a large scale

A solar cell or photovoltaic cell is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect. It is a form of photoelectric cell, a device whose electrical characteristics vary when it is exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as "solar panels". The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts.

<span class="mw-page-title-main">Protocrystalline</span>

A protocrystalline phase is a distinct phase occurring during crystal growth, which evolves into a microcrystalline form. The term is typically associated with silicon films in optical applications such as solar cells.

Organic photovoltaic devices (OPVs) are fabricated from thin films of organic semiconductors, such as polymers and small-molecule compounds, and are typically on the order of 100 nm thick. Because polymer based OPVs can be made using a coating process such as spin coating or inkjet printing, they are an attractive option for inexpensively covering large areas as well as flexible plastic surfaces. A promising low cost alternative to conventional solar cells made of crystalline silicon, there is a large amount of research being dedicated throughout industry and academia towards developing OPVs and increasing their power conversion efficiency.

<span class="mw-page-title-main">Organic solar cell</span> Type of photovoltaic

An organic solar cell (OSC) or plastic solar cell is a type of photovoltaic that uses organic electronics, a branch of electronics that deals with conductive organic polymers or small organic molecules, for light absorption and charge transport to produce electricity from sunlight by the photovoltaic effect. Most organic photovoltaic cells are polymer solar cells.

Monocrystalline silicon, more often called single-crystal silicon, in short mono c-Si or mono-Si, is the base material for silicon-based discrete components and integrated circuits used in virtually all modern electronic equipment. Mono-Si also serves as a photovoltaic, light-absorbing material in the manufacture of solar cells.

<span class="mw-page-title-main">Thin-film solar cell</span> Type of second-generation solar cell

Thin-film solar cells are made by depositing one or more thin layers of photovoltaic material onto a substrate, such as glass, plastic or metal. Thin-film solar cells are typically a few nanometers (nm) to a few microns (µm) thick–much thinner than the wafers used in conventional crystalline silicon (c-Si) based solar cells, which can be up to 200 µm thick. Thin-film solar cells are commercially used in several technologies, including cadmium telluride (CdTe), copper indium gallium diselenide (CIGS), and amorphous thin-film silicon.

<span class="mw-page-title-main">Copper indium gallium selenide solar cell</span>

A copper indium gallium selenide solar cell is a thin-film solar cell used to convert sunlight into electric power. It is manufactured by depositing a thin layer of copper indium gallium selenide solid solution on glass or plastic backing, along with electrodes on the front and back to collect current. Because the material has a high absorption coefficient and strongly absorbs sunlight, a much thinner film is required than of other semiconductor materials.

A plasmonic-enhanced solar cell, commonly referred to simply as plasmonic solar cell, is a type of solar cell that converts light into electricity with the assistance of plasmons, but where the photovoltaic effect occurs in another material.

<span class="mw-page-title-main">Solar cell research</span> Research in the field of photovoltaics

There are currently many research groups active in the field of photovoltaics in universities and research institutions around the world. This research can be categorized into three areas: making current technology solar cells cheaper and/or more efficient to effectively compete with other energy sources; developing new technologies based on new solar cell architectural designs; and developing new materials to serve as more efficient energy converters from light energy into electric current or light absorbers and charge carriers.

<span class="mw-page-title-main">Solar-cell efficiency</span> Ratio of energy extracted from sunlight in solar cells

Solar-cell efficiency refers to the portion of energy in the form of sunlight that can be converted via photovoltaics into electricity by the solar cell.

<span class="mw-page-title-main">Polycrystalline silicon</span> High purity form of silicon

Polycrystalline silicon, or multicrystalline silicon, also called polysilicon, poly-Si, or mc-Si, is a high purity, polycrystalline form of silicon, used as a raw material by the solar photovoltaic and electronics industry.

Low-temperature polycrystalline silicon (LTPS) is polycrystalline silicon that has been synthesized at relatively low temperatures compared to in traditional methods. LTPS is important for display industries, since the use of large glass panels prohibits exposure to deformative high temperatures. More specifically, the use of polycrystalline silicon in thin-film transistors (LTPS-TFT) has high potential for large-scale production of electronic devices like flat panel LCD displays or image sensors.

<span class="mw-page-title-main">Amorphous silicon</span> Non-crystalline silicon

Amorphous silicon (a-Si) is the non-crystalline form of silicon used for solar cells and thin-film transistors in LCDs.

<span class="mw-page-title-main">Heterojunction solar cell</span> A solar cell architecture

Heterojunction solar cells (HJT), variously known as Silicon heterojunctions (SHJ) or Heterojunction with Intrinsic Thin Layer (HIT), are a family of photovoltaic cell technologies based on a heterojunction formed between semiconductors with dissimilar band gaps. They are a hybrid technology, combining aspects of conventional crystalline solar cells with thin-film solar cells.

References

  1. ↑ "Bell Labs Demonstrates the First Practical Silicon Solar Cell". aps.org.
  2. ↑ D. M. Chapin-C. S. Fuller-G. L. Pearson (1954). "A New Silicon p–n Junction Photocell for Converting Solar Radiation into Electrical Power". Journal of Applied Physics. 25 (5): 676–677. Bibcode:1954JAP....25..676C. doi:10.1063/1.1721711.
  3. 1 2 3 4 5 6 "Photovoltaics Report" (PDF). Fraunhofer ISE. 28 July 2014. Archived (PDF) from the original on 9 August 2014. Retrieved 31 August 2014.
  4. 1 2 "Photovoltaics Report" (PDF). Fraunhofer ISE. 22 September 2022. Archived (PDF) from the original on 23 September 2022.
  5. ↑ High-efficiency multi-junction solar cells Archived 2012-03-21 at the Wayback Machine
  6. ↑ "Multi-Junction Solar Cells". stanford.edu.
  7. ↑ "Both-sides-contacted solar cell sets new world record of 26 percent efficiency". techxplore.com. Retrieved 10 May 2021.
  8. ↑ Richter, Armin; Müller, Ralph; Benick, Jan; Feldmann, Frank; Steinhauser, Bernd; Reichel, Christian; Fell, Andreas; Bivour, Martin; Hermle, Martin; Glunz, Stefan W. (April 2021). "Design rules for high-efficiency both-sides-contacted silicon solar cells with balanced charge carrier transport and recombination losses". Nature Energy. 6 (4): 429–438. Bibcode:2021NatEn...6..429R. doi:10.1038/s41560-021-00805-w. ISSN   2058-7546. S2CID   234847037 . Retrieved 10 May 2021.
  9. ↑ "Production Process of Silicon". www.simcoa.com.au. Simcoa Operations. Archived from the original on 19 June 2014. Retrieved 17 September 2014.
  10. ↑ Werner, Jürgen H. (2 November 2011). "Toxic Substances In Photovoltaic Modules" (PDF). postfreemarket.net. Institute of Photovoltaics, University of Stuttgart, Germany - The 21st International Photovoltaic Science and Engineering Conference 2011 Fukuoka, Japan. p. 2. Archived from the original (PDF) on 21 December 2014. Retrieved 23 September 2014.
  11. ↑ "assivated emitter rear contact solar cells are at 20% efficiency today—but price premiums are steep". GreentechMedia. 14 August 2014.
  12. ↑ "What is PERC? Why should you care?". Solar Power World. 5 July 2016.
  13. ↑ "International Technology Roadmap for Photovoltaic (ITRPV)". vdma.org. Retrieved 9 April 2024.
  14. ↑ "PERC Solar Photovoltaic Technology".
  15. ↑ "Archived copy". Archived from the original on 11 April 2009. Retrieved 5 August 2015.{{cite web}}: CS1 maint: archived copy as title (link)
  16. ↑ "Why Panasonic HIT - Panasonic Solar HIT - Eco solutions - Business - Panasonic Global". panasonic.net. Retrieved 17 April 2018.
  17. ↑ Taguchi, Mikio; Terakawa, Akira; Maruyama, Eiji; Tanaka, Makoto (1 September 2005). "Obtaining a higher Voc in HIT cells". Progress in Photovoltaics: Research and Applications. 13 (6): 481–488. doi: 10.1002/pip.646 . ISSN   1099-159X.
  18. ↑ Wang, T.H.; Iwaniczko, E.; Page, M.R.; Levi, D.H.; Yan, Y.; Yelundur, V.; Branz, H.M.; Rohatgi, A.; Wang, Q. (2005). "Effective interfaces in silicon heterojunction solar cells". Conference Record of the Thirty-first IEEE Photovoltaic Specialists Conference, 2005. pp. 955–958. doi:10.1109/PVSC.2005.1488290. hdl:1853/25930. ISBN   978-0-7803-8707-2. S2CID   13507811.
  19. ↑ Wolf, Stefaan De; Kondo, Michio (22 January 2007). "Abruptness of a-Si:H/c-Si interface revealed by carrier lifetime measurements". Applied Physics Letters. 90 (4): 042111. Bibcode:2007ApPhL..90d2111D. doi:10.1063/1.2432297. ISSN   0003-6951.
  20. ↑ Mews, Mathias; Schulze, Tim F.; Mingirulli, Nicola; Korte, Lars (25 March 2013). "Hydrogen plasma treatments for passivation of amorphous-crystalline silicon-heterojunctions on surfaces promoting epitaxy". Applied Physics Letters. 102 (12): 122106. Bibcode:2013ApPhL.102l2106M. doi:10.1063/1.4798292. ISSN   0003-6951.
  21. ↑ Descoeudres, A.; Barraud, L.; Wolf, Stefaan De; Strahm, B.; Lachenal, D.; Guérin, C.; Holman, Z. C.; Zicarelli, F.; Demaurex, B. (19 September 2011). "Improved amorphous/crystalline silicon interface passivation by hydrogen plasma treatment". Applied Physics Letters. 99 (12): 123506. Bibcode:2011ApPhL..99l3506D. doi:10.1063/1.3641899. ISSN   0003-6951.
  22. ↑ Tanaka, Makoto; Taguchi, Mikio; Matsuyama, Takao; Sawada, Toru; Tsuda, Shinya; Nakano, Shoichi; Hanafusa, Hiroshi; Kuwano, Yukinori (1 November 1992). "Development of New a-Si/c-Si Heterojunction Solar Cells: ACJ-HIT (Artificially Constructed Junction-Heterojunction with Intrinsic Thin-Layer)". Japanese Journal of Applied Physics. 31 (Part 1, No. 11): 3518–3522. Bibcode:1992JaJAP..31.3518T. doi:10.1143/jjap.31.3518. S2CID   123520303.
  23. ↑ Street, R. A.; Biegelsen, D. K.; Knights, J. C. (15 July 1981). "Defect states in doped and compensated $a$-Si: H". Physical Review B. 24 (2): 969–984. Bibcode:1981PhRvB..24..969S. doi:10.1103/PhysRevB.24.969.
  24. ↑ Banerjee, A.; Guha, S. (15 January 1991). "Study of back reflectors for amorphous silicon alloy solar cell application". Journal of Applied Physics. 69 (2): 1030–1035. Bibcode:1991JAP....69.1030B. doi:10.1063/1.347418. ISSN   0021-8979.
  25. ↑ De Wolf, Stefaan; Descoeudres, Antoine; Holman, Zachary C.; Ballif, Christophe (2012). "High-efficiency Silicon Heterojunction Solar Cells: A Review" (PDF). Green. 2 (1): 7–24. doi:10.1515/green-2011-0018. S2CID   138517035.
  26. 1 2 Chavali, R.V.K.; Wilcox, J.R.; Ray, B.; Gray, J.L.; Alam, M.A. (1 May 2014). "Correlated Nonideal Effects of Dark and Light I #x2013;V Characteristics in a-Si/c-Si Heterojunction Solar Cells". IEEE Journal of Photovoltaics. 4 (3): 763–771. doi:10.1109/JPHOTOV.2014.2307171. ISSN   2156-3381. S2CID   13449892.
  27. ↑ Matsuura, Hideharu; Okuno, Tetsuhiro; Okushi, Hideyo; Tanaka, Kazunobu (15 February 1984). "Electrical properties of n-amorphous/p-crystalline silicon heterojunctions". Journal of Applied Physics. 55 (4): 1012–1019. Bibcode:1984JAP....55.1012M. doi:10.1063/1.333193. ISSN   0021-8979.
  28. ↑ Taguchi, Mikio; Maruyama, Eiji; Tanaka, Makoto (1 February 2008). "Temperature Dependence of Amorphous/Crystalline Silicon Heterojunction Solar Cells". Japanese Journal of Applied Physics. 47 (2): 814–818. Bibcode:2008JaJAP..47..814T. doi:10.1143/jjap.47.814. S2CID   121128373.
  29. ↑ Chavali, R.V.K.; Moore, J.E.; Wang, Xufeng; Alam, M.A.; Lundstrom, M.S.; Gray, J.L. (1 May 2015). "The Frozen Potential Approach to Separate the Photocurrent and Diode Injection Current in Solar Cells". IEEE Journal of Photovoltaics. 5 (3): 865–873. doi:10.1109/JPHOTOV.2015.2405757. ISSN   2156-3381. S2CID   33613345.
  30. ↑ Lu, Meijun; Das, Ujjwal; Bowden, Stuart; Hegedus, Steven; Birkmire, Robert (1 May 2011). "Optimization of interdigitated back contact silicon heterojunction solar cells: tailoring hetero-interface band structures while maintaining surface passivation". Progress in Photovoltaics: Research and Applications. 19 (3): 326–338. doi:10.1002/pip.1032. ISSN   1099-159X. S2CID   97567531.
  31. 1 2 Chavali, R.V.K.; Khatavkar, S.; Kannan, C.V.; Kumar, V.; Nair, P.R.; Gray, J.L.; Alam, M.A. (1 May 2015). "Multiprobe Characterization of Inversion Charge for Self-Consistent Parameterization of HIT Cells". IEEE Journal of Photovoltaics. 5 (3): 725–735. doi:10.1109/JPHOTOV.2014.2388072. ISSN   2156-3381. S2CID   25652883.
  32. ↑ Kleider, J. P.; Chouffot, R.; Gudovskikh, A. S.; Roca i Cabarrocas, P.; Labrune, M.; Ribeyron, P. -J.; Brüggemann, R. (1 October 2009). "Electronic and structural properties of the amorphous/crystalline silicon interface". Thin Solid Films. Proceedings on the Sixth Symposium on Thin Films for Large Area Electronics. 517 (23): 6386–6391. Bibcode:2009TSF...517.6386K. doi:10.1016/j.tsf.2009.02.092.
  33. ↑ Li, Jian V.; Crandall, Richard S.; Young, David L.; Page, Matthew R.; Iwaniczko, Eugene; Wang, Qi (1 December 2011). "Capacitance study of inversion at the amorphous-crystalline interface of n-type silicon heterojunction solar cells". Journal of Applied Physics. 110 (11): 114502–114502–5. Bibcode:2011JAP...110k4502L. doi:10.1063/1.3663433. ISSN   0021-8979.
  34. ↑ Gudovskikh, A. S.; Kleider, J. -P.; Damon-Lacoste, J.; Roca i Cabarrocas, P.; Veschetti, Y.; Muller, J. -C.; Ribeyron, P. -J.; Rolland, E. (26 July 2006). "Interface properties of a-Si:H/c-Si heterojunction solar cells from admittance spectroscopy". Thin Solid Films. EMSR 2005 - Proceedings of Symposium F on Thin Film and Nanostructured Materials for PhotovoltaicsEMRS 2005- Symposium FEMSR 2005 - Proceedings of Symposium F on Thin Film and Nanostructured Materials for Photovoltaics. 511–512: 385–389. Bibcode:2006TSF...511..385G. doi:10.1016/j.tsf.2005.12.111.
  35. ↑ Schmidt, M.; Korte, L.; Laades, A.; Stangl, R.; Schubert, Ch.; Angermann, H.; Conrad, E.; Maydell, K. v. (16 July 2007). "Physical aspects of a-Si:H/c-Si hetero-junction solar cells". Thin Solid Films. Proceedings of Symposium I on Thin Films for Large Area Electronics EMRS 2007 ConferenceEMRS 2006 - Symposium I. 515 (19): 7475–7480. Bibcode:2007TSF...515.7475S. doi:10.1016/j.tsf.2006.11.087.
  36. ↑ Bivour, Martin; Reichel, Christian; Hermle, Martin; Glunz, Stefan W. (1 November 2012). "Improving the a-Si:H(p) rear emitter contact of n-type silicon solar cells". Solar Energy Materials and Solar Cells. SiliconPV. 106: 11–16. doi:10.1016/j.solmat.2012.06.036.
  37. ↑ Das, Ujjwal; Hegedus, Steven; Zhang, Lulu; Appel, Jesse; Rand, Jim; Birkmire, Robert (2010). "Investigation of hetero-interface and junction properties in silicon heterojunction solar cells". 2010 35th IEEE Photovoltaic Specialists Conference. pp. 001358–001362. doi:10.1109/PVSC.2010.5614372. ISBN   978-1-4244-5890-5. S2CID   24318974.
  38. ↑ Battaglia, Corsin; Nicolás, Silvia Martín de; Wolf, Stefaan De; Yin, Xingtian; Zheng, Maxwell; Ballif, Christophe; Javey, Ali (17 March 2014). "Silicon heterojunction solar cell with passivated hole selective MoOx contact". Applied Physics Letters. 104 (11): 113902. Bibcode:2014ApPhL.104k3902B. doi: 10.1063/1.4868880 . ISSN   0003-6951. S2CID   14976726.
  39. ↑ Masuko, K.; Shigematsu, M.; Hashiguchi, T.; Fujishima, D.; Kai, M.; Yoshimura, N.; Yamaguchi, T.; Ichihashi, Y.; Mishima, T. (1 November 2014). "Achievement of More Than 25 #x0025; Conversion Efficiency With Crystalline Silicon Heterojunction Solar Cell". IEEE Journal of Photovoltaics. 4 (6): 1433–1435. doi:10.1109/JPHOTOV.2014.2352151. ISSN   2156-3381. S2CID   31321943.
  40. ↑ Asadpour, Reza; Chavali, Raghu V. K.; Khan, M. Ryyan; Alam, Muhammad A. (15 June 2015). "Bifacial Si heterojunction-perovskite organic-inorganic tandem to produce highly efficient (ηT* ~ 33%) solar cell". Applied Physics Letters. 106 (24): 243902. arXiv: 1506.01039 . Bibcode:2015ApPhL.106x3902A. doi:10.1063/1.4922375. ISSN   0003-6951. S2CID   109438804.
  41. 1 2 Green, M. A. (2004), "Recent Developments in Photovoltaics", Solar Energy, 76 (1–3): 3–8, Bibcode:2004SoEn...76....3G, doi:10.1016/S0038-092X(03)00065-3 .
  42. ↑ S. A. Campbell (2001), The Science and Engineering of Microelectronic Fabrication (2nd ed.), New York: Oxford University Press, ISBN   978-0-19-513605-0
  43. ↑ Streetman, B. G. & Banerjee, S. (2000), Solid State Electronic Devices (5th ed.), New Jersey: Prentice Hall, ISBN   978-0-13-025538-9 .
  44. ↑ Shah, A. V.; et al. (2003), "Material and solar cell research in microcrystalline silicon" (PDF), Solar Energy Materials and Solar Cells, 78 (1–4): 469–491, doi:10.1016/S0927-0248(02)00448-8 .
  45. ↑ "Technical articles". semiconductor.net. Archived from the original on 15 July 2011. Retrieved 17 April 2018.
  46. ↑ Myong, Seung; Kwon, Seong; Kwak, Joong; Lim, Koeng; Pearce, Joshua; Konagai, Makoto (2006). "Good Stability of Protocrystalline Silicon Multilayer Solar Cells Against Light Irradiation Originating from Vertically Regular Distribution of Isolated Nano-Sized Silicon Grains". 2006 IEEE 4th World Conference on Photovoltaic Energy Conference. pp. 1584–1587. doi:10.1109/WCPEC.2006.279788. ISBN   978-1-4244-0016-4. S2CID   41872657.
  47. ↑ Myong, Seung Yeop; Lim, Koeng Su; Pears, Joshua M. (2005). "Double amorphous silicon-carbide p-layer structures producing highly stabilized pin-type protocrystalline silicon multilayer solar cells" (PDF). Applied Physics Letters. 87 (19): 193509. Bibcode:2005ApPhL..87s3509M. doi:10.1063/1.2126802. S2CID   67779494.
  48. 1 2 3 Kishore, R.; Hotz, C.; Naseem, H. A. & Brown, W. D. (2001), "Aluminum-Induced Crystallization of Amorphous Silicon (α-Si:H) at 150°C", Electrochemical and Solid-State Letters, 4 (2): G14–G16, doi: 10.1149/1.1342182 .
  49. ↑ Yuan, Zhijun; Lou, Qihong; Zhou, Jun; Dong, Jingxing; Wei, Yunrong; Wang, Zhijiang; Zhao, Hongming; Wu, Guohua (2009), "Numerical and experimental analysis on green laser crystallization of amorphous silicon thin films", Optics & Laser Technology, 41 (4): 380–383, Bibcode:2009OptLT..41..380Y, doi:10.1016/j.optlastec.2008.09.003 .
  50. ↑ Lee, Hyun Seok; Choi, Sooseok; Kim, Sung Woo; Hong, Sang Hee (2009), "Crystallization of Amorphous Silicon Thin Film by Using a Thermal Plasma Jet", Thin Solid Films, 517 (14): 4070–4073, Bibcode:2009TSF...517.4070L, doi:10.1016/j.tsf.2009.01.138, hdl: 10371/69100 .
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