Also found in: Dictionary, Thesaurus, Medical, Acronyms, Wikipedia.
ultraviolet light[¦əl·trə′vī·lət ′līt]
ultraviolet lightAn invisible band of radiation at the upper end of the visible light spectrum. With wavelengths from 10 to 400 nm, ultraviolet (UV) starts at the end of visible light and ends at the beginning of X-rays. The primary source of ultraviolet light is the sun, and most of the UV that reaches earth is in the lower-frequency, longer-wavelength Ultraviolet "A" region (see below).
Although ultraviolet (UV) light is widely known as a disinfectant, it was also used to erase EPROM chips. After several minutes of exposure to UV light, the chip could be programmed again (see EPROM).
Ultraviolet for Chip Making
For a long time, chip lithography, which exposes the silicon to a pattern of light, has been using 193 nm far ultraviolet (FUV) as the source. However, because light cannot create a pattern smaller than its own wavelength, several photomasks are used, and complex chips require dozens of lithography steps.
After 10 nm process technology came into production, extreme ultraviolet (EUV) in the 13.5 nm range is considered the next-generation light source because its wavelength is closer to the feature size (see process technology).
Wavelength inUltraviolet Region Nanometers (nm) Long Wave "A" UVA 315-400 Medium Wave "B" UVB 280-315 Short Wave "C" UVC 100-280 Near NUV 300-400 Middle MUV 200-300 Far FUV 122-200 Vacuum VUV 10-200 Extreme EUV 10-121 Deep DUV Below 300
|Ultraviolet in the Spectrum|
|The ultraviolet band comes after visible light and ends at the beginning of X-rays.|