Multiple processes are used to clean both the rear glass plate, on which the TFTs are built, and the front glass plate, on which the color filter layers are applied – both of which are critical to the successful operation of the finished product. These processes range from initial plate cleaning to cleaning prior to the deposition of films and polarizers, and involve the use of a variety of cleaning equipment, including ultrasonic/megasonic immersion tanks, brush cleaning systems and spray washers.
The cavitational energy produced by ultrasonic or megasonic transducers in a cleaning bath increases the cleaning efficiency of the bath. Intersurface Dynamics’ ultrasonic detergents are highly effective when used for the ultrasonic/megasonic cleaning of particles and organic films, and are available in a pH range from acidic to caustic.
Contact cleaning works to remove particles from a substrate utilizing different brush materials, such as PVA, to attract the particle from the surface. Using the correct cleaning chemistry can help to increase particle removal and to remove organic films that are known to interfere with subsequent coating processes. Brush cleaning requires a low to no-foam detergent that will effectively wet the surface of the panel, without detrimentally affecting the brush. Intersurface Dynamics manufacturers detergents formulated to remove particles and organics without impacting the contact cleaning brush/device.
Spraying gently and efficiently removes particles and organics from the surface of a substrate, with none of the risk inherent in contact cleaning. However, spray washing requires a extremely low-foam detergent that can wet and clean the substrate, while keeping surface foam, and hence air pockets, to a minimum. Intersurface Dynamics’ detergents, available at a pH range from acidic to caustic, meet this particular FPD cleaning challenge and are ideal for substrate surface cleaning prior to coating.