Related Research Articles
In integrated circuit manufacturing, photolithography or optical lithography is a general term 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.
In electronics and photonics design, tape-out or tapeout is the final result of the design process for integrated circuits or printed circuit boards before they are sent for manufacturing. The tapeout is specifically the point at which the graphic for the photomask of the circuit is sent to the fabrication facility.
A printed circuit board (PCB) is a laminated sandwich structure of conductive and insulating layers. PCBs have two complementary functions. The first is to affix electronic components in designated locations on the outer layers by means of soldering. The second is to provide reliable electrical connections between the component's terminals in a controlled manner often referred to as PCB design. Each of the conductive layers is designed with an artwork pattern of conductors that provides electrical connections on that conductive layer. Another manufacturing process adds vias, plated-through holes that allow interconnections between layers.
In photography, flash synchronization or flash sync is the synchronizing the firing of a photographic flash with the opening of the shutter admitting light to photographic film or electronic image sensor.
Electronic design automation (EDA), also referred to as electronic computer-aided design (ECAD), is a category of software tools for designing electronic systems such as integrated circuits and printed circuit boards. The tools work together in a design flow that chip designers use to design and analyze entire semiconductor chips. Since a modern semiconductor chip can have billions of components, EDA tools are essential for their design; this article in particular describes EDA specifically with respect to integrated circuits (ICs).
Integrated circuit layout, also known IC layout, IC mask layout, or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make up the components of the integrated circuit. Originally the overall process was called tapeout as historically early ICs used graphical black crepe tape on mylar media for photo imaging.
A photomask is an opaque plate with holes or transparencies that allow light to shine through in a defined pattern. They are commonly used in photolithography and the production of integrated circuits in particular. Masks are used to produce a pattern on a substrate, normally a thin slice of silicon known as a wafer in the case of chip manufacturing. Several masks are used in turn, each one reproducing a layer of the completed design, and together they are known as a mask set.
The Gerber format is an open ASCII vector format for printed circuit board (PCB) designs. It is the de facto standard used by PCB industry software to describe the printed circuit board images: copper layers, solder mask, legend, drill data, etc.
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives, or from transparencies.
A photogram is a photographic image made without a camera by placing objects directly onto the surface of a light-sensitive material such as photographic paper and then exposing it to light.
Masklesslithography (MPL) is a photomask-less photolithography-like technology used to project or focal-spot write the image pattern onto a chemical resist-coated substrate by means of UV radiation or electron beam.
A stepper is a device used in the manufacture of integrated circuits (ICs) that is similar in operation to a slide projector or a photographic enlarger. The term "stepper" is short for step-and-repeat camera. Steppers are an essential part of the complex process, called photolithography, that creates millions of microscopic circuit elements on the surface of chips of silicon. These chips form the heart of ICs such as computer processors, memory chips, and many other devices.
Computer-to-plate (CTP) is an imaging technology used in modern printing processes. In this technology, an image created in a Desktop Publishing (DTP) application is output directly to a printing plate.
Selective soldering is the process of selectively soldering components to printed circuit boards and molded modules that could be damaged by the heat of a reflow oven or wave soldering in a traditional surface-mount technology (SMT) or through-hole technology assembly processes. This usually follows an SMT oven reflow process; parts to be selectively soldered are usually surrounded by parts that have been previously soldered in a surface-mount reflow process, and the selective-solder process must be sufficiently precise to avoid damaging them.
Solder mask, solder stop mask or solder resist is a thin lacquer-like layer of polymer that is usually applied to the copper traces of a printed circuit board (PCB) for protection against oxidation and to prevent solder bridges from forming between closely spaced solder pads. A solder bridge is an unintended electrical connection between two conductors by means of a small blob of solder. PCBs use solder masks to prevent this from happening. Solder mask is not always used for hand soldered assemblies, but is essential for mass-produced boards that are soldered automatically using reflow or wave soldering techniques. Once applied, openings must be made in the solder mask wherever components are soldered, which is accomplished using photolithography. Solder mask is traditionally green, but is also available in many other colors.
In the manufacture of electronic printed circuit boards, flying probes are for testing of bare circuit boards and boards loaded with components. Flying probes were introduced in the late 1980’s. Flying probes can be found in many manufacturing and assembly operations. A flying probe tester uses one or more test probes to make contact with the circuit board under test; the probes are moved from place to place on the circuit board to carry out tests of multiple conductors or components. Flying probe testers are an alternative to 'bed of nail" testers, which use multiple contacts to simultaneously contact the board and which relay on electrical switching to carry out measurements.
Photosensitive glass, also known as photostructurable glass (PSG), or photomachinable glass, is a crystal-clear glass that belongs to the lithium-silicate family of glasses, in which an image of a mask can be captured by microscopic metallic particles in the glass when it is exposed to short wave radiations such as ultraviolet light. Photosensitive glass was first discovered by S. Donald Stookey in 1937.
Stencil printing is the process of depositing solder paste on the printed wiring boards (PWBs) to establish electrical connections. It is immediately followed by the component placement stage. The equipment and materials used in this stage are a stencil, solder paste, and a printer.
A contact copier, is a device used to copy an image by illuminating a film negative with the image in direct contact with a photosensitive surface. The more common processes are negative, where clear areas in the original produce an opaque or hardened photosensitive surface, but positive processes are available. The light source is usually an actínic bulb internal or external to the device
References
- ↑ Raymond H. Clark (6 December 2012). Handbook of Printed Circuit Manufacturing. Springer Science & Business Media. pp. 17–. ISBN 978-94-011-7012-3.
- ↑ Electronic Products. United Technical Publications. 1989.
- ↑ Electronic Packaging and Production. Cahners Pub. 1987.
- ↑ Carill Sharpe (1994). Kempe's Engineers Year-book. Morgan Bros.
- ↑ David J. Gerber (2015). The Inventor's Dilemma: The Remarkable Life of H. Joseph Gerber. Yale University Press. pp. 167–. ISBN 978-0-300-12350-0.
- 1 2 3 Chris Schroeder (1998). Printed Circuit Board Design Using AutoCAD. Newnes. ISBN 978-0-7506-9834-4.
- ↑ Jorge L.C. Sanz (1 December 1988). Advances in Machine Vision. Springer Science & Business Media. pp. 196–. ISBN 978-0-387-96822-3.
- 1 2 R. S. Khandpur (2005). Printed Circuit Boards: Design, Fabrication, Assembly and Testing. Tata McGraw-Hill Education. ISBN 978-0-07-058814-1.
- 1 2 Kraig Mitzner (28 May 2009). Complete PCB Design Using OrCAD Capture and PCB Editor. Newnes. ISBN 978-0-08-094354-1.