Roll-to-roll processing

Last updated
A typical industrial roll-to-roll process line. R2R line.jpg
A typical industrial roll-to-roll process line.

In the field of electronic devices, roll-to-roll processing, also known as web processing, [1] reel-to-reel processing or R2R, [2] is the process of creating electronic devices on a roll of flexible plastic, metal foil, or flexible glass. [3] In other fields predating this use, it can refer to any process of applying coating, printing, or performing other processes starting with a roll of a flexible material and re-reeling after the process to create an output roll. These processes, and others such as sheeting, can be grouped together under the general term converting . When the rolls of material have been coated, laminated or printed they can be subsequently slit to their finished size on a slitter rewinder.

Contents

In electronic devices

Large circuits made with thin-film transistors and other devices can be patterned onto these large substrates, which can be up to a few metres wide and 50 km (31 mi) long.[ citation needed ] Some of the devices can be patterned directly, much like an inkjet printer deposits ink. For most semiconductors, however, the devices must be patterned using photolithography techniques.

Roll-to-roll processing of large-area electronic devices reduces manufacturing cost. [4] [2] Most notable would be solar cells, which are still prohibitively expensive for most markets due to the high cost per unit area of traditional bulk (mono- or polycrystalline) silicon manufacturing. Other applications could arise which take advantage of the flexible nature of the substrates, such as electronics embedded into clothing, large-area flexible displays, and roll-up portable displays.

LED (Light Emitting Diode)

Thin-film cells

A crucial issue for a roll-to-roll thin-film cell production system is the deposition rate of the microcrystalline layer, and this can be tackled using four approaches: [5]

In electrochemical devices

The roll-to-roll processing has been used in the manufacture of electrochemical devices such as batteries, [6] supercapacitors, [7] fuel cells, [8] [9] and water electrolyzers. [10] Here, the roll-to-roll processing is utilized for electrode manufacturing and is the key to reducing manufacturing cost [11] through stable production of electrodes on various film substrates such as metal foils, membranes, diffusion media, and separators.

See also

Related Research Articles

<span class="mw-page-title-main">Chemical vapor deposition</span> Method used to apply surface coatings

Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films.

<span class="mw-page-title-main">Organic electronics</span> Field of materials science

Organic electronics is a field of materials science concerning the design, synthesis, characterization, and application of organic molecules or polymers that show desirable electronic properties such as conductivity. Unlike conventional inorganic conductors and semiconductors, organic electronic materials are constructed from organic (carbon-based) molecules or polymers using synthetic strategies developed in the context of organic chemistry and polymer chemistry.

<span class="mw-page-title-main">OLED</span> Diode that emits light from an organic compound

An organic light-emitting diode (OLED), also known as organic electroluminescentdiode, is a type of light-emitting diode (LED) in which the emissive electroluminescent layer is an organic compound film that emits light in response to an electric current. This organic layer is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, and portable systems such as smartphones and handheld game consoles. A major area of research is the development of white OLED devices for use in solid-state lighting applications.

Indium tin oxide (ITO) is a ternary composition of indium, tin and oxygen in varying proportions. Depending on the oxygen content, it can be described as either a ceramic or an alloy. Indium tin oxide is typically encountered as an oxygen-saturated composition with a formulation of 74% In, 8% Sn, and 18% O by weight. Oxygen-saturated compositions are so typical that unsaturated compositions are termed oxygen-deficient ITO. It is transparent and colorless in thin layers, while in bulk form it is yellowish to gray. In the infrared region of the spectrum it acts as a metal-like mirror.

A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films is a fundamental step in many applications. A familiar example is the household mirror, which typically has a thin metal coating on the back of a sheet of glass to form a reflective interface. The process of silvering was once commonly used to produce mirrors, while more recently the metal layer is deposited using techniques such as sputtering. Advances in thin film deposition techniques during the 20th century have enabled a wide range of technological breakthroughs in areas such as magnetic recording media, electronic semiconductor devices, integrated passive devices, LEDs, optical coatings, hard coatings on cutting tools, and for both energy generation and storage. It is also being applied to pharmaceuticals, via thin-film drug delivery. A stack of thin films is called a multilayer.

<span class="mw-page-title-main">Flexible organic light-emitting diode</span> Type of computer monitor

A flexible organic light-emitting diode (FOLED) is a type of organic light-emitting diode (OLED) incorporating a flexible plastic substrate on which the electroluminescent organic semiconductor is deposited. This enables the device to be bent or rolled while still operating. Currently the focus of research in industrial and academic groups, flexible OLEDs form one method of fabricating a rollable display.

<span class="mw-page-title-main">Coating</span> Substance spread over a surface

A coating is a covering that is applied to the surface of an object, or substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids e.g. powder coatings.

Atomic layer deposition (ALD) is a thin-film deposition technique based on the sequential use of a gas-phase chemical process; it is a subclass of chemical vapour deposition. The majority of ALD reactions use two chemicals called precursors. These precursors react with the surface of a material one at a time in a sequential, self-limiting, manner. A thin film is slowly deposited through repeated exposure to separate precursors. ALD is a key process in fabricating semiconductor devices, and part of the set of tools for synthesizing nanomaterials.

<span class="mw-page-title-main">Printed electronics</span> Electronic devices created by various printing methods

Printed electronics is a set of printing methods used to create electrical devices on various substrates. Printing typically uses common printing equipment suitable for defining patterns on material, such as screen printing, flexography, gravure, offset lithography, and inkjet. By electronic-industry standards, these are low-cost processes. Electrically functional electronic or optical inks are deposited on the substrate, creating active or passive devices, such as thin film transistors; capacitors; coils; resistors. Some researchers expect printed electronics to facilitate widespread, very low-cost, low-performance electronics for applications such as flexible displays, smart labels, decorative and animated posters, and active clothing that do not require high performance.

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

Stretchable electronics, also known as elastic electronics or elastic circuits, is a group of technologies for building electronic circuits by depositing or embedding electronic devices and circuits onto stretchable substrates such as silicones or polyurethanes, to make a completed circuit that can experience large strains without failure. In the simplest case, stretchable electronics can be made by using the same components used for rigid printed circuit boards, with the rigid substrate cut to enable in-plane stretchability. However, many researchers have also sought intrinsically stretchable conductors, such as liquid metals.

<span class="mw-page-title-main">Ultrasonic nozzle</span> Type of spray nozzle

Ultrasonic nozzles are a type of spray nozzle that use high frequency vibrations produced by piezoelectric transducers acting upon the nozzle tip that create capillary waves in a liquid film. Once the amplitude of the capillary waves reaches a critical height, they become too tall to support themselves and tiny droplets fall off the tip of each wave resulting in atomization.

<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.

<span class="mw-page-title-main">Thin-film lithium-ion battery</span> Type of battery

The thin film lithium-ion battery is a form of solid-state battery. Its development is motivated by the prospect of combining the advantages of solid-state batteries with the advantages of thin-film manufacturing processes.

<span class="mw-page-title-main">AMOLED</span> Display technology for use in mobile devices and televisions

AMOLED is a type of OLED display device technology. OLED describes a specific type of thin-film-display technology in which organic compounds form the electroluminescent material, and active matrix refers to the technology behind the addressing of pixels.

<span class="mw-page-title-main">Transparent conducting film</span> Optically transparent and electrically conductive material

Transparent conducting films (TCFs) are thin films of optically transparent and electrically conductive material. They are an important component in a number of electronic devices including liquid-crystal displays, OLEDs, touchscreens and photovoltaics. While indium tin oxide (ITO) is the most widely used, alternatives include wider-spectrum transparent conductive oxides (TCOs), conductive polymers, metal grids and random metallic networks, carbon nanotubes (CNT), graphene, nanowire meshes and ultra thin metal films.

<span class="mw-page-title-main">Nanocrystal solar cell</span>

Nanocrystal solar cells are solar cells based on a substrate with a coating of nanocrystals. The nanocrystals are typically based on silicon, CdTe or CIGS and the substrates are generally silicon or various organic conductors. Quantum dot solar cells are a variant of this approach which take advantage of quantum mechanical effects to extract further performance. Dye-sensitized solar cells are another related approach, but in this case the nano-structuring is a part of the substrate.

Flexible solar cell research is a research-level technology, an example of which was created at the Massachusetts Institute of Technology in which solar cells are manufactured by depositing photovoltaic material on flexible substrates, such as ordinary paper, using chemical vapor deposition technology.

<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.

In materials science, vertically aligned carbon nanotube arrays (VANTAs) are a unique microstructure consisting of carbon nanotubes oriented with their longitudinal axis perpendicular to a substrate surface. These VANTAs effectively preserve and often accentuate the unique anisotropic properties of individual carbon nanotubes and possess a morphology that may be precisely controlled. VANTAs are consequently widely useful in a range of current and potential device applications.

<span class="mw-page-title-main">Slot-die coating</span> Technique for coating flat substrates

Slot-die coating is a coating technique for the application of solution, slurry, hot-melt, or extruded thin films onto typically flat substrates such as glass, metal, paper, fabric, plastic, or metal foils. The process was first developed for the industrial production of photographic papers in the 1950's. It has since become relevant in numerous commercial processes and nanomaterials related research fields.

References

  1. "Digital roll-to-roll web processing revolutionizes printed electronic production". Control Engineering. March 12, 2013. Retrieved February 1, 2018.
  2. 1 2 Goswami, Debkalpa; Munera, Juan C.; Pal, Aniket; Sadri, Behnam; Scarpetti, Caio Lui P. G.; Martinez, Ramses V. (2018-05-18). "Roll-to-Roll Nanoforming of Metals Using Laser-Induced Superplasticity". Nano Letters. 18 (6): 3616–3622. Bibcode:2018NanoL..18.3616G. doi:10.1021/acs.nanolett.8b00714. ISSN   1530-6984. PMID   29775318.
  3. Tamagaki, Hiroshi; Ikari, Yoshimitu; Ohba, Naoki (2014). "Roll-to-roll sputter deposition on flexible glass substrates". Surface and Coatings Technology. 241: 138–141. doi:10.1016/j.surfcoat.2013.10.056 via ResearchGate.
  4. Wong, William S.; Salleo, Alberto, eds. (2009). "Fabrication on Web by Roll-to-Roll Processing". Flexible Electronics: Materials and Applications. New York, NY: Springer. p. 19. ISBN   978-0387743639.
  5. "PV projects in FP6". Archived from the original on June 18, 2006. Retrieved 2008-11-25.
  6. US11446915B2,Biswas, Kaushik; III, David Lee Wood& Grady, Kelsey M.et al.,"Roll-to-roll slot die coating method to create interleaving multi-layered films with chemical slurry coatings",issued 2022-09-20
  7. Yeo, Junyeob; Kim, Geonwoong; Hong, Sukjoon; Kim, Min Su; Kim, Daewon; Lee, Jinhwan; Lee, Ha Beom; Kwon, Jinhyeong; Suh, Young Duk; Kang, Hyun Wook; Sung, Hyung Jin; Choi, Jun-Ho; Hong, Won-Hwa; Ko, Jang Myoun; Lee, Seung-Hyun (2014-01-15). "Flexible supercapacitor fabrication by room temperature rapid laser processing of roll-to-roll printed metal nanoparticle ink for wearable electronics application". Journal of Power Sources. 246: 562–568. Bibcode:2014JPS...246..562Y. doi:10.1016/j.jpowsour.2013.08.012. ISSN   0378-7753. S2CID   94203734.
  8. Steenberg, Thomas; Hjuler, Hans Aage; Terkelsen, Carina; Sánchez, María T. R.; Cleemann, Lars N.; Krebs, Frederik C. (2012-03-01). "Roll-to-roll coated PBI membranes for high temperature PEM fuel cells". Energy & Environmental Science. 5 (3): 6076–6080. doi:10.1039/C2EE02936G. ISSN   1754-5706. S2CID   95139481.
  9. Mauger, Scott A.; Neyerlin, K. C.; Yang-Neyerlin, Ami C.; More, Karren L.; Ulsh, Michael (2018-09-11). "Gravure Coating for Roll-to-Roll Manufacturing of Proton-Exchange-Membrane Fuel Cell Catalyst Layers". Journal of the Electrochemical Society. 165 (11): F1012. doi: 10.1149/2.0091813jes . ISSN   1945-7111. S2CID   105303844.
  10. Park, Janghoon; Kang, Zhenye; Bender, Guido; Ulsh, Michael; Mauger, Scott A. (2020-12-15). "Roll-to-roll production of catalyst coated membranes for low-temperature electrolyzers". Journal of Power Sources. 479: 228819. Bibcode:2020JPS...47928819P. doi: 10.1016/j.jpowsour.2020.228819 . ISSN   0378-7753. S2CID   224915162.
  11. Mauler, Lukas; Duffner, Fabian; Leker, Jens (2021-03-15). "Economies of scale in battery cell manufacturing: The impact of material and process innovations". Applied Energy. 286: 116499. doi: 10.1016/j.apenergy.2021.116499 . ISSN   0306-2619. S2CID   233658321.