File Spinner.jpg thumb A spin coater used to apply photoresist to the surface of a silicon wafer. No footnotes date March 2010 Spin coating is a procedure used to apply uniform thin film s to flat Substrate printing substrate s. In short, an excess amount of a solution is placed on the substrate, which is then rotated at high speed in order to spread the fluid by centrifugal force . A machine used for spin coating is called a spin coater , or simply spinner . Rotation is continued while the fluid spins off the edges of the substrate, until the desired thickness of the film is achieved. The applied solvent is usually Volatility chemistry volatile , and simultaneously evaporation evaporates . So, the higher the angular speed of spinning, the thinner the film. The thickness of the film also depends on the concentration of the solution and the solvent. Spin coating is widely used in microfabrication , where it can be used to create thin films with thicknesses below 10 nanometer nm . It is used intensively in photolithography , to deposit layers of photoresist about 1 micrometre thick. Photoresist is typically spun at 20 to 80 revolutions per second for 30 to 60 seconds. Owing to the low values of thickness which can be achieved using spin coating methods, this method is often employed in the fabrication of transparent Titanium dioxide thin films on quartz or glass substrates ref cite journal author Hanaor D, Triani G, Sorrell C title Morphology and photocatalytic activity of highly oriented mixed phase titanium dioxide thin films journal Surface and Coatings Technology year 2011 volume 205 issue 12 pages 855 874 doi 10.1016 j.surfcoat.2011.01.007 ref , such thin film coatings may exhibit self cleaning and self sterilizing properties. Stages of spin coating Image EVG 120 resist coater developer at LAAS 0434.jpg thumb EVG 120 fully automated photoresist coater developer under inactinic light at Laboratory for analysis and architecture of systems LAAS technological facility ... more details
the p MOSFETs with photoresist. Ion implantation is then completed, with ions of the chosen dopant type penetrating the gate oxide in areas where no photoresist is present. The photoresist is then stripped .... The photoresist is stripped. At some point during the subsequent fabrication process, implanted ... more details
unreferenced date April 2012 The term stepping level in the context of CPU architecture or integrated circuitry is a version number. Stepping level refers to the introduction or revision of the lithographic mask or masks within the set of plates that generate the pattern that produces the CPU or integrated circuit. The term derives from the name of the equipment Stepper steppers that exposes the photoresist to light. ref name JumpingJack cite web url http www.tomshardware.com forum 235792 28 what stepping author JumpingJack publisher Tom s Hardware accessdate 30 Jul 2008 title What is CPU Stepping? 404 date April 2012 ref Typically, when an integrated circuit manufacturer such as Intel or AMD invests money to do a stepping i.e. a revision to the masks , they have found bugs in the logic, have made improvements to the design that allow for faster processing, or have found a way to increase yield or improve the bin splits i.e. create faster transistors and hence faster CPUs . One result of some new steppings is that the CPU design is improved such that it Overclocking overclocks better than others. ref name JumpingJack Many CPUs have a means of interrogating them in order to discover their stepping level. For example, on x86 CPUs executing the CPUID with the EAX register set to 1 will place values in other registers that show the CPU s stepping level. See also Core microarchitecture Steppings Steppings of the Intel Core microarchitecture References references DEFAULTSORT Stepping Level Category Microprocessors Category Central processing unit microcompu stub de Stepping Mikroprozessoren fr Stepping ko it Stepping microprocessori ru uk ... more details
for the photoresist KMPR1000 Infobox radio station name KMPR image city Minot, North Dakota area branding Prairie Public Radio slogan frequency Frequency 88.9 MHz HD Radio translator K220FD Harvey, North Dakota Harvey repeater airdate Start date YYYY MM DD share share as of share source format Public broadcasting Public Jazz , Classical music Classical , All news radio News br small HD2 Relay of KFJM Grand Forks, North Dakota Grand Forks small language power erp 50,000 watt s haat convert 283 m ft sp us class C1 facility id 53319 coordinates callsign meaning M inot P ublic R adio former callsigns former frequencies affiliations Prairie Public , National Public Radio NPR owner Prairie Public Broadcasting licensee Prairie Public Broadcasting, Inc. sister stations webcast http www.prairiepublic.org radio listen now Stream website http www.prairiepublic.org prairiepublic.org KMPR 88.9 FM is a radio station licensed to Minot, North Dakota . The station is owned by Prairie Public Broadcasting , and broadcasts Prairie Public Radio s Radio Western Service of jazz , classical music and All news radio news and talk programming. Translators KMPR is relayed by an additional Broadcast relay station translator station . RadioTranslators call1 K220FD city1 Harvey, North Dakota freq1 91.9 FM watts1 38 watts External links http www.prairiepublic.org radio Prairie Public radio website FM station data KMPR br clear all Minot radio NPR North Dakota coord 48.051 N 101.390 W type landmark region US source FCC display title Category Prairie Public Radio Category Radio stations in North Dakota Category NPR member stations NorthDakota radio station stub ... more details
chembox verifiedrevid 470604806 ImageFile TMAH.svg ImageSize IUPACName tetramethylammonium hydroxide OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 54928 InChI 1 C4H12N.H2O c1 5 2,3 4 h1 4H3 1H2 q 1 p 1 InChIKey WGTYBPLFGIVFAS REWHXWOFAQ StdInChI Ref stdinchicite correct chemspider StdInChI 1S C4H12N.H2O c1 5 2,3 4 h1 4H3 1H2 q 1 p 1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey WGTYBPLFGIVFAS UHFFFAOYSA M CASNo 75 59 2 CASNo Ref cascite correct CAS PubChem 60966 SMILES C N C C C. OH Section2 Chembox Properties C 4 H 13 N 1 O 1 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Section8 Chembox Related OtherAnions tetramethylammonium chloride OtherCations tetraethylammonium hydroxide Tetramethylammonium hydroxide TMAH or TMAOH is a quaternary ammonium salt with the molecular formula CH sub 3 sub sub 4 sub NOH. It is used as an anisotropic etchant of silicon. It is also used as a basic solvent in the photographic processing development of acidic photoresist in the photolithography process. Since it is a phase transfer catalyst , it is highly effective in stripping photoresist. It is also used as a surfactant in the synthesis of ferrofluid , to prevent agglomeration . Toxicity TMAH solution is a strong base. The tetramethylammonium ion can damage nerves and muscles, causing difficulties in breathing and possibly death in a short period of time after exposure by contact, even with only a small amount. It is structurally similar to acetylcholine , an important peripheral neurotransmitter at both the neuromuscular junction and autonomic ganglia . This structural similarity is reflected in its mechanism of toxicity it binds to and activates the nicotinic acetylcholine receptors, although the response may subsequently densentize in the continued presence of this agonist. The action of tetramethylammonium is most pronounced in autonomic ganglia, an ... more details
is grown on top of the gate oxide. 4. A layer of photoresist is applied on top of the polysilicon . 5. A mask is placed on top of the photoresist and exposed to Ultra violet light UV light this breaks down the photoresist layer in areas where the mask didn t protect it. 6. Photoresist is exposed with a specialized developer solution. This is intended to remove the photoresist that was broken down by the UV light. 7. The polysilicon and gate oxide that is not covered by photoresist ... acid . 8. The rest of the photoresist is stripped from the silicon wafer. There is now a wafer ... more details
refimprove date April 2009 Photoengraving also known as photo chemical milling is a process of engraving using photographic processing techniques. The full form of photoengraving is photo mechanical process in the graphic arts, used principally for reproducing illustrations. The subject is photographed, and the image is recorded on a sensitized metal plate, which is then etched in an acid bath. In the case of line cuts drawings in solid blacks and whites without gradations of color , the photoengraving is done on zinc, and the result is called a zinc etching. In the case of halftone cuts, the work is done on copper. The halftone effect is accomplished by photographing the subject through a wire or glass screen, which breaks the Ray optics light rays so that the metal plate is sensitized in a dotted pattern the larger dots create the darker areas, the smaller dots the highlights. The finer the screen, the greater the precision of detail in the printed product. Halftones made with a screen having 65 lines to the inch are considered coarse. Those having 150 lines to the inch are considered fine. File DianaLouvre.jpg thumb right An 1899 photoengraving of the original marble statue, Diana of Versailles at the Louvre The most common type of photoengraving involves using a material that is photosensitive and resistant to acid s or other etching compound s. This material, called a photoresist , is applied to a metal to be engraved. It is then exposed to light usually strong ultraviolet through a photography photographic negative causing it to harden where the negative allows light to pass. The photoresist is then developed by washing in a solvent that removes the unhardened parts. Finally, the metal to be engraved is exposed to an acid or other etching compound which dissolves the exposed parts of the metal. Photoengraving is used to make printed circuit board s, printing plate s, postage stamp foil stamping Die manufacturing dies and Embossing manufacturing embossing dies. ... more details
, that translates approximately into 35 x photoresist coating, exposure, development, main process step like etching, diffusion, metal filling , photoresist stripping and or polishing, and other possible ... more details
for a similar process on printed circuit boards Photolithography Photochemical machining PCM , also known as photochemical milling or photo etching , is the process of fabricating sheet metal components using a photoresist and etchants to corrosively machine away selected areas. This process emerged in the 1960s as an offshoot of the printed circuit board industry. Photo etching can produce highly complex parts with very fine detail accurately and economically. This process can offer economical alternatives to stamping metalworking stamping , punching , laser cutting laser or Water jet cutter water jet cutting, or wire electrical discharge machining EDM for thin gauge precision parts. The tooling is inexpensive and quickly produced. This makes the process useful for prototyping and allows for easy changes in mass production. It maintains dimensional Engineering tolerance tolerances and does not create burrs or sharp edges. It can make a part in hours after receiving the drawing. PCM can be used on virtually any commercially available metal or alloy, of any hardness. It is limited to materials with a thickness of convert 0.0005 to 0.080 in mm abbr on . Metals include aluminium , brass , copper , inconel , manganese , nickel , silver , steel , stainless steel , zinc and titanium . Process The process starts by printing the shape of the part onto optically clear and dimensionally stable photographic film . The phototool consists of two sheets of this film showing negative images of the parts meaning that the area that will become the parts is clear and all of the areas to be etched are black . The two sheets are optically and mechanically registered to form the top and bottom halves of the tool. ref Degarmo, p. 690. ref The metal sheets are cut to size, cleaned and then laminated on both sides with a UV sensitive photoresist . The coated metal is placed between the two sheets of the phototool and a vacuum is drawn to ensure intimate contact between the phototool and th ... more details
Infobox Journal cover File Journal of Materials Chemistry.gif discipline Materials Science abbreviation J. Mater. Chem. editor Liz Davies impact 4.795 2010 website http www.rsc.org Publishing Journals jm publisher Royal Society of Chemistry country United Kingdom history 1991 to present impact factor 4.795 ISSN 0959 9428 eISSN 1364 5501 CODEN JMACEP Journal of Materials Chemistry is a peer review peer reviewed scientific journal publishing original research original primary research and literature review review articles on the applications, properties and synthesis of exciting new materials. Journal of Materials Chemistry is published weekly by the Royal Society of Chemistry . The managing editor editor of Journal of Materials Chemistry is Liz Davies. Journal of Materials Chemistry has an impact factor of 4.795 2010 . ref Journal Citation Reports, June 2010 ref Subject coverage Journal of Materials Chemistry publishes articles on the following topics Inorganic ceramic s layered materials microporous solids and zeolites silicates and synthetic minerals biogenic minerals nanomaterial s biomaterial bio related materials organometallic precursors for thin films ceramics Organic novel molecular solids and synthetic polymers with materials applications polymer composites biopolymer s biocompatible and biodegradable polymers liquid crystal s both lyotropic and thermotropic Langmuir Blodgett film s and self assembled monolayers SAMs , nanomaterial s, biomaterial s Electrical properties of materials semiconductor semi , metallic and superconductivity super conductivity ionic conductivity mixed ionic electronic conductivity ferroelectric ferro , pyroelectric pyro and piezoelectric piezo electricity electroceramic s dielectric s Optical properties of materials luminescence , phosphorescence , laser action non linear optics non linear optical effects photoconductivity photochromism photo and electrochromism electro chromism , photoresist resists , glasses, amorphous semiconduct ... more details
Warren T. Thompson active 1840 1870 was an United States American photographer. Between 1840 and 1846 Thompson worked in Philadelphia, Pennsylvania Philadelphia and in 1843 refined Daniel Davis Jr. photographer Daniel Davis Jr. s electroplating method for colouring daguerreotypes by using a gum tragacanth Photoresist resist . With this technique colours could be built up in the manner of some types of printmaking. According to editor of the in an article in the 1892 American Journal of photography by editor Julius S Sachse, Thompson traveled to Paris in 1845 from New York without speaking any French and with an introduction from the Russian Consul in New York to the Russian Vice Consul in Paris who in turn arranged an introduction to Russian photographer Sergei Lvovich Levitsky . Levitsky is quoted by Sachse as declaring Thompson s daguerreotypes were works of art . Sachse further claims that Thompson influenced for the development of portrait daguerreotypes in Paris. From 1849 50 Thompson was listed as a photographer at at 14 boulevarde Poissonni re, rue rue Basse du Rempart in 1851, then 22 rue de Choiseul from 1853 59. Levitsky returned to Russia by 1849 but came back to Paris by 1859 where he took over Thompson s Choiseul address. This was also the premises for the French arts club. Thompson aka as surname Warren Thompson produced daguerreotypes in Paris as well as very fine stereo daguerreotypes and a number of theatrical self portraits some of very large size, but his body of known work is scant. The skill of his surviving work suggests he may have trained as a painter. For a pioneer era photographer whose role appears to have been quite prominent in Paris in the 1840s and 50s, Thompson s career is poorly known. References Elliott, Alan. http www.melbournephoto.org.au alanelliottmcc.html A Daguerreotype http www.getty.edu vow ULANFullDisplay?find 28 13 11davis 13 11daniel 29 7C 13 11davis 11daniel&role &nation &prev page 1&subjectid 500111789 Union List of Art ... more details
Infobox company company name Shin Etsu Chemical Co., Ltd. company logo Image Shin Etsu Chemical logo.svg 200px company type public company Public Kabushiki kaisha KK tyo 4063 foundation 1926 as Shin Etsu Nitrogen Fertilizer location Tokyo, Japan key people Chihiro Kanagawa, President & CEO industry Chemical industry Chemicals products Chemical industry Chemicals revenue profit 1,376,365 million Japanese yen JPY fiscal year FY 2007 net income profit 183,580 million Japanese yen JPY fiscal year FY 2007 num employees 20,241 2008 homepage http www.shinetsu.co.jp e www.shinetsu.co.jp nihongo Shin Etsu Chemical Co., Ltd. Shin etsu Kagaku K gy Kabushiki Kaisha tyo 4063 is the largest chemical industry chemical company in Japan, ranked No. 9 in Forbes Global 2000 for chemical sector. Shin Etsu has the largest global market share for polyvinyl chloride , semiconductor silicon and photomask substrates. Shin Etsu in the company s name derives from Shin etsu Region , where the company established the first chemical plant as Shin Etsu Nitrogen Fertilizer in 1926, though the company today is headquartered in Tokyo and has its manufacturing locations in 14 countries worldwide. Segments Shin Etsu splits its business into three distinct groups Organic and inorganic chemicals Main products polyvinyl chloride PVC , silicones, methanol , chloromethane , cellulose derivatives, povals, caustic soda , and silicon metals Electronics materials Main products semiconductor silicon, organic materials, rare earth magnets for the electronics industry and photoresist products Functional materials Main products synthetic quartz, rare earth and rare earth magnets for general use References http www.shinetsu.co.jp e ir pdf 2007 annual2008.pdf Shin Etsu Chemical Annual Report 2008 External links en http www.shinetsu.co.jp e Shin Etsu Chemical TOPIX 100 Category Companies based in Tokyo Category Chemical companies of Japan Category Companies established in 1926 Category Silicon wafer produ ... more details
of the art processes. However, the photographic developer used for photoresist resembles wet etching ... Simplified illustration of dry etching using positive photoresist during a photolithography process ... and silicon nitride . A plasma containing oxygen is used to oxidize plasma ashing ash photoresist ... Mo Tetrafluoromethane CF sub 4 sub ref name WolfDry Organic residues and photoresist Piranha ... more details
broadening in the photoresist while the pitch resolution limit is determined by secondary electrons secondary electron travel in the photoresist . ref name broers cite journal title Electron beam lithography ... by using higher energy electrons or thinner photoresist, but the generation of secondary electrons ... considerations not related to image formation, e.g., photoresist development and intermolecular ... beam with sufficient energy to penetrate the photoresist can be multiply scattered over large distances ..., it will be imperative to use low energy electrons as the primary radiation to expose photoresist ... eV in order to expose the photoresist without generating any secondary electrons, since they will not have ... polymer photoresist. The drawback to using low energy electrons is that it is hard to prevent spreading of the electron beam in the photoresist. ref name mayer cite journal title Field emission characteristics ... more details
it is also used as a mechanical stress buffer. Some polyimide can be used like a photoresist both positive and negative types of photoresist like polyimide exist in the market. An additional use ... more details
together. Impact of multiple etch patterning In contrast to multiple exposure of the same photoresist film, multiple patterning multiple layer patterning entails repeated photoresist coating, deposition ... more details
Infobox company company name ASML Holding N.V. company logo File ASML Holding N.V. logo.svg 200px company type Naamloze vennootschap Euronext ASML , NASDAQ ASML foundation 1984 location Veldhoven , Netherlands key people Eric Meurice small chief executive officer CEO small , Peter Wennink small chief financial officer CFO small , Arthur van der Poel small Chairman of the supervisory board small products Photolithography systems for the semiconductor industry industry Semiconductor industry revenue Euro 4.508 billion small 2010 small ref name AR2010 cite web url http www.asml.com doclib investor annual reports 2010 u09689 IM Feb14.pdf title Annual Report 2010 accessdate 16 February 2011 publisher ASML ref operating income 1.251 billion small 2010 small ref name AR2010 net income 1.022 billion small 2010 small ref name AR2010 assets 6.180 billion small end 2010 small ref name AR2010 equity 2.774 billion small end 2010 small ref name AR2010 num employees 9,245 small full time equivalent FTE , end 2010 small ref name AR2010 intl yes homepage http asml.com ASML is a Netherlands Dutch company and the largest supplier in the world of photolithography systems for the semiconductor industry. The company manufactures machines for the production of integrated circuits ICs , such as Dynamic random access memory DRAM memory , flash memory , and CPU s. Products Image ASML headquarters Veldhoven.jpg left thumb 200px ASML s corporate headquarters in Veldhoven The photolithography machines manufactured by ASML are used in the production of computer chips. In these machines, patterns are optically imaged onto a silicon wafer electronics wafer that is covered with a film of light sensitive material photoresist . This procedure is repeated dozens of times on a single wafer. The photoresist is then further processed to create the actual electronic circuits on the silicon. The optical imaging, that ASML s machines deal with, is used in the fabrication of nearly all integrated circuits, a ... more details
Unreferenced date December 2010 Copper based chips are semiconductor integrated circuit s, usually microprocessor s, which use copper for Interconnection semiconductors interconnection s. Since copper is a better conductor than aluminium , chips using this technology can have smaller metal components, and use less energy to pass electricity through them. Together, these effects lead to higher performance processors. The transition from aluminium to copper required significant developments in fabrication semiconductor fabrication techniques, including radically different methods for patterning the metal as well as the introduction of barrier metal layers to isolate the silicon from potentially damaging copper atoms. Patterning Because of the lack of volatile copper compounds, copper could not be patterned by the previous techniques of photolithography photoresist masking and plasma etching that had been used with great success with aluminium. The inability to plasma etch copper called for a drastic rethinking of the metal patterning process and the result of this rethinking was a process referred to as an additive patterning or a Damascening Damascene or dual Damascene process. In this process, the underlying silicon oxide insulating layer is patterned with open trenches where the conductor should be. A thick coating of copper that significantly overfills the trenches is deposited on the insulator, and chemical mechanical planarization CMP also called chemical mechanical polishing is used to remove the copper to the level of the top of the insulating layer. Copper sunken within the trenches of the insulating layer is not removed and becomes the patterned conductor. Damascene processes generally form and fill a single feature with copper per Damascene stage. Dual Damascene processes generally form and fill two features with copper at once, e.g., a trench overlying a via electronics via may both be filled with a single copper deposition using dual Damascene. With succe ... more details
CMOS manufacturing processes The 90 nanometre nm process refers to the level of CMOS process technology that was reached in the 2002 2003 timeframe, by most leading semiconductor companies, like Intel , AMD , Infineon , Texas Instruments , IBM , and TSMC . The origin of the 90 nm value is historical, as it reflects a trend of 70 scaling every 2 3 years. The naming is formally determined by the International Technology Roadmap for Semiconductors ITRS . The 193 nm wavelength was introduced by many but not all companies for photolithography lithography of critical layers mainly during the 90 nm node. Yield issues associated with this transition due to the use of new photoresist s were reflected in the high costs associated with this transition. Even more significantly, the 300 mm wafer size became mainstream at the 90 nm node. The previous wafer size was 200 mm diameter. Example Elpida 90 nm DDR2 SDRAM process ref Elpida s presentation at Via Technology Forum 2005 and Elpida 2005 Annual Report ref Use of 300 mm wafer size Use of KrF 248 nm lithography with optical proximity correction 512 Mbit 1.8 V operation Derivative of earlier 110 nm and 100 nm processes Processors using 90 nm process technology IBM PowerPC G5 PowerPC 970FX PowerPC G5 970FX 2004 IBM PowerPC G5 PowerPC 970MP PowerPC G5 970MP 2005 IBM PowerPC G5 PowerPC 970GX PowerPC G5 970GX 2005 IBM Xenon processor Waternoose Xbox 360 Processor 2005 IBM Sony Toshiba Cell microprocessor Cell Processor 2005 Intel Pentium 4 Prescott 2004 02 Intel Celeron D Prescott 256 2004 05 Intel Pentium M Dothan microprocessor Dothan 2004 05 Intel Celeron M Dothan microprocessor Dothan 1024 2004 08 Intel Xeon Nocona, Irwindale, Cranford, Potomac, Paxville 2004 06 Intel Pentium D Smithfield 2005 05 AMD Athlon 64 Winchester, Venice, San Diego, Orleans 2004 10 AMD Athlon 64 X2 Manchester, Toledo, Windsor 2005 05 AMD Sempron Palermo and Manila 2004 08 AMD Turio ... more details
otheruses In semiconductor fabrication , a resist is a thin layer used to transfer a circuit pattern to the semiconductor substrate which it is deposited upon. A resist can be patterned via photolithography lithography to form a sub micrometer scale, temporary mask that protects selected areas of the underlying substrate during subsequent processing steps. The material used to prepare said thin layer is typically a viscous solution. Resists are generally proprietary mixtures of a polymer or its precursor and other small molecules e.g. photoacid generators that have been specially formulated for a given lithography technology. Resists used during photolithography are called photoresist s. Background Semiconductor devices as of 2005 are built by depositing and patterning many thin layers. The patterning steps, or lithography, define the function of the device and the density of its components. For example, in the interconnect layers of a modern microprocessor, a conductive material copper or aluminum is inlaid in an Electrical insulation electrically insulating matrix typically fluorinated silicon dioxide or another low k dielectric . The metal patterns define multiple electrical circuits that are used to connect the microchip s transistor s to one another and ultimately to external devices via the chip s pins. The most common patterning method used by the semiconductor device industry is photolithography patterning using light. In this process, the substrate of interest is coated with photosensitive resist and irradiated with short wavelength light projected through a photomask , which is a specially prepared stencil formed of opaque and transparent regions usually a quartz substrate with a patterned chromium layer. The shadow of opaque regions in the photomask forms a submicrometer scale pattern of dark and illuminated regions in the resist layer the areal image . Chemical and physical changes occur in the exposed areas of the resist layer. For example, chemical bon ... more details
absorbed. Other variants include CMY and CMYW matrices. Manufacture of the CFA Photoresist Absorption at UV and shorter wavelengths Diazonaphthoquinone DNQ novolac photoresist is one material used as the carrier ... image sensors using a chemically amplified, thermally cured, pre dyed, positive tone photoresist ... Optics ref Gersteltec sells photoresist s that possesses color filter properties. ref cite web url ... more details
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