We demonstrate a first application, of optical-feedback cavity-enhanced absorption spectroscopy (OF-CEAS) to breath analysis in a medical environment. Noninvasive monitoring of trace species in exhaled air was performed simultaneous to spirometric measurements on patients at Bichat Hospital (Paris). The high selectivity of the OF-CEAS spectrometer and a time response of 0.3 s (limited by sample flow rate) allowed following the evolution of carbon monoxide and methane concentrations during individual respiratory cycles, and resolving variations among different ventilatory patterns. The minimum detectable absorption on this time scale is about 3 x 10(-10) cm(-1). At the working wavelength of the instrument (2.326 microm), this translates to concentration detection limits of approximately 1 ppbv (45 picomolar, or approximately 1.25 microg/m(3)) for CO and 25 ppbv for CH(4), well below concentration values found in exhaled air. This same instrument is also able to provide measurement of NH(3) concentrations with a detection limit of approximately 10 ppbv; however, at present, memory effects do not allow its measurement on fast time scales.

For more than hundred years, different types of spectrometers based on a dispersive element or an interferometric scanning configuration have been designed and used. Miniaturization of such systems has been achieved, but with each principle there is a trade-off between miniaturization and performance.

Soft ultraviolet laser desorption of neutral and ionized Si atoms was investigated at 355 nm for fluences ranging from the desorption threshold ͑85 mJ/cm 2 ) up to 165 mJ/cm 2 . The sensitivity of resonance ionization mass spectrometry enabled the number of sputtered particles to be studied at a very low emission level corresponding to only several 100 atoms. For such a low emission yield, the ejected atoms keeps the memory of the laser-surface interaction mechanism during their flight in the ultrahigh vacuum condition. The velocity distribution of neutrals was measured for different fluences and were well fitted by a set of 2 Maxwellian functions at each fluence. From these fits it appears that the primary mechanisms involved in laser desorption are both a thermal process and an electronic one.

The development and operation of a multi watt, multi kHz and low debris EUV gas discharge source is reported. The Capillary EUV Lamp for Lithography Approach (CAPELLA) is designed and characterized for its application in the french EUV exposure tool named BEL. The burst operation at high repetition rate, up to 3 kHz, of the source during time period of a few seconds is described and shown to be relevant for the BEL application. The long time stability over hours is measured to be of 0.6 %. Other technical BEL requirements such as energy flux, EUV output stability, spatial position stability, collection angle are briefly presented and their fulfilment is documented through the experimental data obtained on the CAPELLA prototype. An experimental characterization of debris nature and deposition rate on plasma facing silicon targets has been performed over millions of shots showing evidence of the crucial role of the discharge regime.