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-Glossary
+#Glossary
+##Fabrication
+Fabrication (or Manufacturing)is the process of building circuits on a silicon wafer in a cleanroom environment where all aspects of production (temperature, power, chemistries, moisture, contamination, etc.) are tightly controlled. It take 40 to 150 days to complete the fabrication process.
+##Cleanroom
+Cleanroom is a room that has HEPA (High Efficiency Particulate Air) filtration to remove
+particles from the air. Cleanrooms are used for manufacturing where high levels of
+cleanliness and sterility are required. Common applications of the cleanroom
+include manufacturing of medical devices, pharmaceuticals, and semiconductors.
+##Chemical mechanical planarization (CMP)
+CMP is used to smooth the surface of wafers following other manufacturing steps, such as etching and cleaning. CMP allow a new layer of features to be added.
+##Cleaning
+Cleaning involves removing residues left on the wafer by the etching process.
+##Deposition
+Deposition adds thin films of materials on a wafer to become parts of chips. Techniques include chemical vapor deposition, physical vapor deposition, electrochemical coating, spin-coating, rapid thermal processing, and tube- based diffusion and deposition.
+###CVD
+Chemical vapor deposition (CVD) tools create a chemical vapor that deposits films on the wafer atom-by-atom or molecule-by-molecule.
+###PVD
+Physical vapor deposition (PVD) tools vaporize a solid or liquid material, which then condenses onto a substrate. The primary PVD method is called "sputtering."
+###RTP
+Rapid thermal processing (RTP) is critical to several steps in chip manufacturing. RTP tools include lamps, lasers, or other mechanisms to quickly increase the temperature of a wafer in order to change its properties.
+###Spin-coating
+These tools spin a wafer to spread liquid material deposited on the wafer across it. Spin-coating is used extensively in photoresist coating but only for narrow applications in chip production.
+###tube-based diffusion and deposition
+Tube-based diffusion and deposition systems are called "tube‚"-based because substrates are loaded in cylindrical chambers for processing, either causing diffusion of dopants into a wafer (tube diffusion systems) or depositing materials for particular applications (tube deposition systems).
+##Design
+Design determines the layout of transistors and wiring on a chip to be manufactured.
+##DRAM
+Dynamic random-access memory (DRAM) is a memory chip that stores data while a computer operates, but loses it when the computer powers down.
+##EDA
+Electronic design automation (EDA) software is used to design chips.
+##Etching
+Etching tools are used to create permanent patterns on chips: after photolithography has removed certain parts of a photoresist deposited on a wafer according to a specific pattern, the etching tools etch this pattern into a permanent substrate bellow. Dry etching and wet etching use a gas and a liquid, respectively, for the etching process.
+##FPGA
+Field-programmable gate arrays (FPGAs) are logic chips that can be reprogrammed after deployment to suit specific calculations.
+##Foundries
+Foundries are semiconductor manufacturing facilities that manufacture chips for third-party customers.
+##GPU
+Graphics processing units (GPUs) are specialized logic chips used most commonly for graphics processing and developing artificial intelligence algorithms.
+##Photolithography
+In photolithography, light is used to draw patterns into semiconductor wafers, creating the tiny circuits that comprise logic chips. A photolithography tool passes light through a photomask-a transparent plate with a circuit pattern-to transfer that pattern to a wafer coated with photoresist chemical. The light dissolves parts of the photoresist according to the circuit pattern.
+###ArF dry (DUV)
+ArF (Argon hexa Fluoride) dry lithography scanners are advanced deep ultraviolet (DUV) photolithography tools used in high-volume semiconductor manufacturing.
+###ArF immersion (DUV)
+Immersion ArF is the same as dry ArF except the Scanner lens is immersed in a fluid, typically water.
+###KrF (DUV) lithography tools
+KrF lithography tools are deep ultraviolet (DUV) photolithography tools that use 248 nm wavelength light from krypton fluoride lasers to pattern semiconductor features for mature node semiconductors.
+###i-line lithography tools
+i-line lithography tools are ultraviolet (UV) photolithography systems used in semiconductor manufacturing for mature process nodes.
+###EUV lithography tools
+EUV lithography tools are the most advanced photolithography equipment currently used in mass semiconductor production. They are the only tools combining leading-edge precision (by producing light with small wavelengths) with high throughput (by using photomasks), and are necessary for mass-producing the most advanced logic chips.
+##IDM
+Integrated device manufacturers (IDMs) are firms that perform all three steps of production: design; fabrication; and assembly, testing, and packaging.
+##Ion implanters
+Ion implanters embed impurities (called dopants) into parts of wafers to change their properties.
+##NAND
+NAND flash is a memory chip that stores memory permanently, even when power is turned off.
+##OSAT
+Outsourced semiconductor assembly and test (OSAT) firms perform assembly, testing, and packaging for third-party customers.
+##Packaging
+Packaging involves attaching a manufactured chip to an encasing package.
+##Photomasks
+Photomasks are transparent plates featuring a circuit pattern through which photolithography equipment directs light in order to transfer this pattern onto the chip. Each photomask is specific to one chip design.
+##Photoresist
+Photoresists are chemicals deposited on a wafer that selectively dissolve to form the circuit pattern when exposed to patterned light that has passed through a photomask after being generated by a photolithography tool.
+##Resist processing tools
+Resist processing tools, also called "tracks," coat photoresists on wafers (typically by spin-coating, which spins the wafer to spread deposited photoresist), develop them (dissolve portions hit by light), and bake them (harden undissolved photoresist to prepare for etching).