Parylene (XY) conformal coatings are known and recommended because of their many beneficial performance characteristics. They provide uniform, pinhole-free protective films with excellent barrier/dielectric/insulative properties, able to conform to virtually any substrate configuration. One property in particular – micron-thin coating layers – distinguishes XY from liquid coating materials such as acrylic (AR), epoxy (ER), silicone (SR) and urethane (UR), which need to be applied at least twice as thick in most cases and frequently more, limiting their range of uses. Parylene typically is applied at 0.1 to 50 microns (0.004 -2 mils), while the thicknesses of liquid coatings generally range from 25 to 250 microns (1-10 mils). Compared to liquid processes, gravity and surface tension generate negligible impact with parylene, eliminating film bridging, pinholes, puddling, run-off, sagging or thin-out during application. XY’s coefficient of friction coefficient can be as low as 0.25 to 0.30.Read More
Parylene Coating Blog by Diamond-MT
Of the five most commonly used conformal coatings, four – acrylic (AR), epoxy (ER), silicone (SR) and urethane (UR) – are classified as wet materials, meaning they are applied to substrates by three basic types of liquid-based technology:Read More
Each conformal coating material exhibits a range of unique performance properties that determine its product uses. Relevant factors include the required coating-thickness necessary to assure reliable performance. Like other coating types, parylene (XY) layer thickness is largely a function of several factors: (1) substrate material, (2) the kind of assembly being covered, and (3) its operational purpose. Chemically inert parylene is effective at far-thinner application thickness than liquid-applied materials for coating printed circuit boards (PCBs) and related electro assemblies:Read More
Methods for Measuring Conformal Coating ThicknessRead More
Coating thickness is critical to the proper functioning of your printed wiring assembly, circuit board, or electronic device.Read More
Type xy conformal coating refers to parylene conformal coating. Parylene gets the type xy from its’ full name, para-xylylene. It was shortened to parylene and eventually type xy so that it could be grouped with the other conformal coatings (type ar, ur, etc.).
Acrylic conformal coatings, such as MG Chemicals 419C and Humiseal 1B31 are a very popular conformal coating choice. They are used primarily for moisture protection on printed circuit boards. Often times, they are the cheapest conformal coating to apply because of their easy to use nature. As a result of this, people try to apply acrylic conformal coating as a DIY project. An issue that arises frequently is an improper thickness of coating, resulting in lackluster protection.
Maintaining proper thickness for silicone conformal coating is critical because it is applied very thick compared to other conformal coatings. If a coating is applied too thick, it may create excessive stresses on solder joints and components (particularly glass-bodied components). If a coating is applied too thin, it may not reach the optimum properties described on the Technical Data Sheet. For this reason, the IPC created the J-STD-001 to regulate and standardize the thickness that coatings are applied at. For silicones, the J-STD-001 calls out 0.00197 to 0.00827 in. Our operators strive to hit between .002” and .008” for silicone applications.
WHAT ARE MEMS?
Microelectromechanical systems (MEMS) is the technology of very small devices; it merges at the nano-scale into nanoelectromechanical systems (NEMS) and nanotechnology. MEMS are made up of components between 1 to 100 micrometres in size (i.e. 0.001 to 0.1 mm), and MEMS devices generally range in size from 20 micrometres (20 millionths of a metre) to a millimetre (i.e. 0.02 to 1.0 mm). They usually consist of a central unit that processes data (the microprocessor) and several components that interact with the outside such as microsensors.