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Photoresist
A photoresist (also known simply as a resist) is a light-sensitive material used in several processes, such as photolithography and photoengraving, to form a patterned coating on a surface. This process is crucial in the electronic industry. The process begins by coating a substrate with a light-sensitive organic material. A patterned mask is then applied to the surface to block light, so that only unmasked regions of the material will be exposed to light. A solvent, called a developer, is then applied to the surface. In the case of a positive photoresist, the photo-sensitive material is degraded by light and the developer will dissolve away the regions that were exposed to light, leaving behind a coating where the mask was placed. In the case of a negative photoresist, the photosensitive material is strengthened (either polymerized or cross-linked) by light, and the developer will dissolve away only the regions that were not exposed to light, leaving behind a coating in areas w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoresist Of Photolithography
A photoresist (also known simply as a resist) is a light-sensitive material used in several processes, such as photolithography and photoengraving, to form a patterned coating on a surface. This process is crucial in the electronic industry. The process begins by coating a substrate with a light-sensitive organic material. A patterned mask is then applied to the surface to block light, so that only unmasked regions of the material will be exposed to light. A solvent, called a developer, is then applied to the surface. In the case of a positive photoresist, the photo-sensitive material is degraded by light and the developer will dissolve away the regions that were exposed to light, leaving behind a coating where the mask was placed. In the case of a negative photoresist, the photosensitive material is strengthened (either polymerized or cross-linked) by light, and the developer will dissolve away only the regions that were not exposed to light, leaving behind a coating in areas w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photolithography
In integrated circuit manufacturing, photolithography or optical lithography is a general term used for techniques that use light to produce minutely patterned thin films of suitable materials over a substrate, such as a silicon wafer, to protect selected areas of it during subsequent etching, deposition, or implantation operations. Typically, ultraviolet light is used to transfer a geometric design from an optical mask to a light-sensitive chemical (photoresist) coated on the substrate. The photoresist either breaks down or hardens where it is exposed to light. The patterned film is then created by removing the softer parts of the coating with appropriate solvents. Conventional photoresists typically consists of three components: resin, sensitizer, and solvent. Photolithography processes can be classified according to the type of light used, such as ultraviolet, deep ultraviolet, extreme ultraviolet, or X-ray. The wavelength of light used determines the minimum feature si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SU-8 Photoresist
SU-8 is a commonly used epoxy-based negative photoresist. Negative refers to a photoresist whereby the parts exposed to UV become cross-linked, while the remainder of the film remains soluble and can be washed away during development. As shown in the structural diagram, SU-8 derives its name from the presence of 8 epoxy groups. This is a statistical average per moiety. It is these epoxies that cross-link to give the final structure. It can be made into a viscous polymer that can be spun or spread over a thickness ranging from below 1 micrometer up to above 300 micrometers, or Thick Film Dry Sheets (TFDS) for lamination up to above 1 millimetre thick. Up to 500 µm the resist can be processed with standard contact lithography. Above 500 µm absorption leads to increasing sidewall undercuts and poor curing at the substrate interface. It can be used to pattern high aspect ratio structures. An aspect ratio of (> 20) has been achieved with the solution formulation a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photopolymer
A photopolymer or light-activated resin is a polymer that changes its properties when exposed to light, often in the ultraviolet or visible region of the electromagnetic spectrum. These changes are often manifested structurally, for example hardening of the material occurs as a result of cross-linking when exposed to light. An example is shown below depicting a mixture of monomers, oligomers, and photoinitiators that conform into a hardened polymeric material through a process called curing. A wide variety of technologically useful applications rely on photopolymers; for example, some enamels and varnishes depend on photopolymer formulation for proper hardening upon exposure to light. In some instances, an enamel can cure in a fraction of a second when exposed to light, as opposed to thermally cured enamels which can require half an hour or longer. Curable materials are widely used for medical, printing, and photoresist technologies. Changes in structural and chemical propertie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SU-8 For Negative Photoresist
SU-8 is a commonly used epoxy-based negative photoresist. Negative refers to a photoresist whereby the parts exposed to UV become cross-linked, while the remainder of the film remains soluble and can be washed away during development. As shown in the structural diagram, SU-8 derives its name from the presence of 8 epoxy groups. This is a statistical average per moiety. It is these epoxies that cross-link to give the final structure. It can be made into a viscous polymer that can be spun or spread over a thickness ranging from below 1 micrometer up to above 300 micrometers, or Thick Film Dry Sheets (TFDS) for lamination up to above 1 millimetre thick. Up to 500 µm the resist can be processed with standard contact lithography. Above 500 µm absorption leads to increasing sidewall undercuts and poor curing at the substrate interface. It can be used to pattern high aspect ratio structures. An aspect ratio of (> 20) has been achieved with the solution formulation a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SU-8
SU-8 is a commonly used epoxy-based negative photoresist. Negative refers to a photoresist whereby the parts exposed to UV become cross-linked, while the remainder of the film remains soluble and can be washed away during development. As shown in the structural diagram, SU-8 derives its name from the presence of 8 epoxy groups. This is a statistical average per moiety. It is these epoxies that cross-link to give the final structure. It can be made into a viscous polymer that can be spun or spread over a thickness ranging from below 1 micrometer up to above 300 micrometers, or Thick Film Dry Sheets (TFDS) for lamination up to above 1 millimetre thick. Up to 500 µm the resist can be processed with standard contact lithography. Above 500 µm absorption leads to increasing sidewall undercuts and poor curing at the substrate interface. It can be used to pattern high aspect ratio structures. An aspect ratio of (> 20) has been achieved with the solution formulation a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novolac
Novolaks (sometimes: novolacs) are low molecular weight polymers derived from phenols and formaldehyde. They are related to Bakelite, which is more highly crosslinked. The term comes from Swedish "lack" for lacquer and Latin "novo" for new, since these materials were envisioned to replace natural lacquers such as copal, copal resin. Typically novolaks are prepared by the condensation of phenol or a mixture of p- and m-cresol with formaldehyde (as formalin). The reaction is acid catalyzed. Oxalic acid is often used because it can be subsequently removed by thermal decomposition. Novolaks have a degree of polymerization of approximately 20-40. The branching density, determined by the processing conditions, m- vs p-cresol ratio, as well as CH2O/cresol ratio is typically around 15%. Novolaks are especially important in microelectronics where they are used as photoresist materials. They are also used as tackifiers in rubber. See also * Epoxy References {{reflist Phenol form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazonaphthoquinone
Diazonaphthoquinone (DNQ) is a diazo derivative of naphthoquinone. Upon exposure to light, DNQ converts to a derivative that is susceptible to etching. In this way, DNQ has become an important reagent in photoresist technology in the semiconductor industry. Diazonaphthoquinone sulfonic acid esters are components of common photoresist materials. Such photoresists are used in the manufacture of semiconductors. In this application DNQs are mixed with Novolac resin, a type of phenolic polymer. The DNQ functions as a dissolution inhibitor. During the masking/patterning process, portions of the photoresist film are exposed to light while others remain unexposed. In the unexposed regions of the resist film, the DNQ acts as a dissolution inhibitor and the resist remains insoluble in the aqueous base developer. In the exposed regions, the DNQ forms a ketene, which, in turn, reacts with ambient water to form a base soluble indene carboxylic acid. The exposed regions of the photoresist f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contact. For h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Silsesquioxane
200px, thumbnail, Hydrogen silsesquioxane (R = H). Hydrogen silsesquioxane(s) (HSQ, H-SiOx, THn, H-resin) are inorganic compounds with the empirical formula SiO3/2sub>n. The cubic H8Si8O12 (TH8) is used as the visual representation for HSQ. TH8, TH10, TH12, and TH14 have been characterized by EA), gas chromatography–mass spectroscopy ( GC-MS), IR spectroscopy, and NMR spectroscopy . High purity semiconductor-grade HSQ has been investigated as a negative resist in photolithography and electron-beam (e-beam) lithography. HSQ is commonly delivered in methyl isobutyl ketone ( MIBK) and can be used to form 0.01–2 µm films on substrates/wafers. When exposed to electrons or extreme ultraviolet radiation (EUV), HSQ cross-links via hydrogen evolution concomitant with Si-O bond crosslink In chemistry and biology a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KTH Royal Institute Of Technology
The KTH Royal Institute of Technology ( sv, Kungliga Tekniska högskolan, lit=Royal Institute of Technology), abbreviated KTH, is a public research university in Stockholm, Sweden. KTH conducts research and education in engineering and technology and is Sweden's largest technical university. Currently, KTH consists of five schools with four campuses in and around Stockholm. KTH was established in 1827 as the ''Teknologiska institutet (Institute of Technology)'' and had its roots in the ''Mekaniska skolan (School of Mechanics)'' that was established in 1798 in Stockholm. But the origin of KTH dates back to the predecessor of the ''Mekaniska skolan'', the ''Laboratorium mechanicum'', which was established in 1697 by the Swedish scientist and innovator Christopher Polhem. The Laboratorium mechanicum combined education technology, a laboratory, and an exhibition space for innovations. In 1877 KTH received its current name, Kungliga Tekniska högskolan (KTH Royal Institute of Technol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethylammonium Hydroxide
Tetramethylammonium hydroxide (TMAH or TMAOH) is a quaternary ammonium salt with molecular formula N(CH3)4+ OH−. It is commonly encountered in form of concentrated solutions in water or methanol. TMAH in solid state and its aqueous solutions are all colorless, but may be yellowish if impure. Although TMAH has virtually no odor when pure, samples often have a strong fishy smell due to presence of trimethylamine which is a common impurity. TMAH has several diverse industrial and research applications. Chemical properties Structure TMAH is most commonly encountered as an aqueous solution, in concentrations from ~2–25%, and less frequently as solutions in methanol. These solutions are identified by CAS numbe75-59-2 Several hydrates such as N(CH3)4OH·xH2O. have been crystallized. These salts contain well separated Me4N+ cations and hydroxide anions ( Me is an abbreviation of methyl group). The hydroxide groups are linked by hydrogen bonds to the water of crystallization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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