Detection of Trace Species with Cavity Ring-Down Spectroscopy

Trace moisture detection using continuous-wave cavity ring-down spectroscopy.

We have developed an instrument to measure trace concentrations of small hydride species in gases using continuous-wave cavity ring-down spectroscopy with near-infrared diode laser excitation. An rms baseline equivalent absorbance of 9.2 x 10(-11) cm(-1)/square root(n) is found, where n is the number of ring-down transients. When the 1396.376-nm absorption line of water is used, this correspond...

Species-Specific Sputtering Measurements with Cavity Ring-Down Spectroscopy

We report sputtering studies using cavity ring-down spectroscopy (CRDS). The high sensitivity of the technique and its non-intrusive nature make it amenable to both in situ device studies as well as basic characterization studies. We provide demonstrative measurements of sputtered particles showing the ability to determine species-specific number density and velocity. We summarize a spatial-sca...

Trace Gas Detection with Cw Cavity Ring-down Laser Absorption Spectroscopy

Cavity-locked ring-down spectroscopy

Cavity ring-down spectroscopy sensor for detection of hydrogen chloride

A laser-based cavity ring-down spectroscopy (CRDS) sensor for measurement of hydrogen chloride (HCl) has been developed and characterized. The instrument uses light from a distributed-feedback diode laser at 1742 nm coupled to a high finesse optical cavity to make sensitive and quantifiable concentration measurements of HCl based on optical absorption. The instrument has a (1σ ) limit of detect...