We have constructed and characterized a simple probe that is suitable for accurate measurements of irradiance in the UV to the vacuum UV spectral range. The irradiance meter consists of a PtSi detector located behind a 5-mm-diameter aperture. The probe was characterized at various wavelengths ranging from 130 to 320 nm by use of continuously tunable synchrotron radiation from the Synchrotron Ultraviolet Radiation Facility III. We determined the irradiance responsivity by scanning a small monochromatic beam over the active area of the irradiance meter and measuring its response on a grid with regular spacing. The angular response was also determined and shown to be suitable for applications such as photolithography. In addition, we studied the radiation damage using a 157-nm excimer laser and found that the irradiance meter can endure more than 100 J/cm2 of 157-nm radiation before a noticeable change occurs in its responsivity. Many industrial applications such as UV curing, photolithography, or semiconductor chip fabrication that require accurate measurement of the irradiance would benefit from having such a stable, accurate UV irradiance meter.
[Optical Society of America ]
(040.6070) Detectors : Solid state detectors
(040.7190) Detectors : Ultraviolet
(120.0280) Instrumentation, measurement, and metrology : Remote sensing and sensors
(120.5630) Instrumentation, measurement, and metrology : Radiometry
Ping-Shine Shaw, Rajeev Gupta, and Keith R. Lykke, "Characterization of an Ultraviolet and a Vacuum-ultraviolet Irradiance Meter with Synchrotron Radiation," Appl. Opt. 41, 7173-7178 (2002)