UVOTECH Systems Inc of Concord, CA, USA, a manufacturer and distributor of surface treatment equipment, has launched the Model HELIOS-500 UV-ozone cleaning system, the first product in the firm's HELIOS series of UV-ozone cleaners.
Designed to be compact, lightweight and economical, the HELIOS-500 includes an ultraviolet grid lamp for increased uniformity as well as a digital process timer that allows more accurate control over the process time. The drawer loading sample stage can accommodate up to 5"x5" substrates. Included pedestals allow adjustment of the distance between the UV source and substrate. The system also comes with a built-in hour-counter to record the total hours of UV lamp usage for maintenance purposes.
The UV ozone cleaning process is a photo-sensitized oxidation process in which the contaminant molecules of photo-resists, resins, human skin oil, cleaning solvent residues, silicone oils and flux are excited and/or dissociated by the absorption of short-wavelength UV radiation. Atomic oxygen is simultaneously generated when molecular oxygen is dissociated by 185nm and ozone by 254nm ultraviolet wavelengths. The 254nm UV radiation is absorbed by most hydrocarbons and also by ozone. The products of this excitation of contaminant molecules react with atomic oxygen to form simpler, volatile molecules that desorb from the surface. Therefore, when both UV wavelengths are present, atomic oxygen is continuously generated, and ozone is continually formed and destroyed.
UVOTECH says that, using a UV-ozone cleaner, near atomically clean surfaces can be achieved in minutes without any damage to the devices. This fast method of obtaining ultra-clean surfaces free of organic contaminants on most substrates, such as quartz, silicon, gold, nickel, aluminum, gallium arsenide, alumina etc, can be achieved by using a UV-ozone cleaner in just a few minutes, says the firm.