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The behavior of the CH3 radical density in a parallel-plate RF CH4 plasma diluted with rare gases (He, Ne, Ar, Kr, and Xe) was investigated systematically using infrared diode laser absorption spectroscopy. The CH3 radical density increased in CH4/Xe and CH4/Kr plasmas with increasing rare gas dilution. The Xe* atom densities in the lowest metastable state 3 P 2 and the resonant state 3 P 1 were measured in CH4/Xe plasma through absorption spectroscopy using a Xe hollow cathode lamp in order to clarify the role of Xe* (3 P 2 and 3 P 1) atoms. It was shown that the increase in the CH3 radical density in CH4/Xe plasma was mainly caused by the collision of Xe* atoms with CH4 molecules.

Diamond films were successfully synthesized in both parallel-plate radio frequency ͑rf: 13.56 MHz͒ CH 4 and CH 3 OH plasmas with injection of H and OH radicals generated in the remote microwave ͑2.45 GHz͒ H 2 /H 2 O plasma. Effects of H, OH, and CH 3 radicals on the diamond film formation in the rf plasma reactor were investigated by the formation of diamond films employing radical injection technique and the measurement of density in the plasma. Under the condition of diamond film formation, CH 3 density was measured by infrared diode laser absorption spectroscopy ͑IRLAS͒. The kinetics of CH 3 in rf CH 4 and CH 3 OH plasmas with injection of H and OH radicals were evaluated from the results of optical emission spectroscopy and lifetime of CH 3 radicals estimated by IRLAS.

Both anisotropic ablation and thin film formation of polytetrafluoroethylene (PTFE) were successfully demonstrated using synchrotron radiation (SR) irradiation of PTFE, that is, the SR ablation process. Anisotropic ablation by the SR irradiation was performed at an extremely high rate of 3500 µm/min at a PTFE target temperature of 200° C. Moreover, a PTFE thin film was formed at a high rate of 2.6 µm/min using SR ablation of PTFE. The chemical structure of the deposited film was similar to that of the PTFE target as determined from Fourier transform infrared absorption spectroscopy (FT-IR) analysis.

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In holographic spectroscopy spurious lines appear during optical reconstruction when the spectral hologram recording goes nonlinear. These ghost lines may lead to wrong interpretation of the observed spectrum in the higher orders. This has been experimentally demonstrated using an Ar-ion laser source in all-line operation. It is shown that the higher-order spectra require careful interpretation when used to enhance resolution in holographic spectroscopy.Résumé. En spectroscopie holographique, des fausses raies apparaissent lors de la reconstruction optique, lorsque l'enregistrement de l'hologramme est non-linéaire. Ces raies fantômes peuvent conduireà une fausse interprétation du spectre observé aux ordres supérieurs. On a démontré expérimentalement cet effet en utilisant une source laserà ions d'argon opérant avec toutes ses raies. On montre que les spectres d'ordre supérieur demandent une interprétation soigneuse quand on les utilise pour augmenter la résolution en spectroscopie holographique.

A new plasma chemical vapor deposition (P-CVD) system was developed for synthesis of diamond. This system consisted of a parallel-plate radio frequency (RF) (13.56 MHz) plasma reactor, with a radical source using a microwave (2.45 GHz) discharge plasma and substrate heating using a cw-CO2 laser. In this system, hydrogen (H) radicals were generated in the microwave H2 plasma and preferentially injected near the substrate in the parallel-plate RF magnetron methanol ( CH3OH) plasma region. By scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses, it was found that diamond was successfully synthesized using this system. The effects of H radical on the diamond formation were also investigated from the results of optical emission measurements in the RF plasma region, thin-film deposition and etching of the nondiamond phases by varying amounts of H radical injection.

CH3 radical densities in electron cyclotron resonance (ECR) discharge methanol ( CH3OH), methanol diluted with hydrogen gas ( CH3OH/H2) and methane ( CH4) plasmas were measured for the first time using infrared diode laser absorption spectroscopy (IRLAS). CH3 radical densities in the CH3OH and CH3OH/H2 plasmas were estimated to be of the order of 1011 cm-3 under the conditions of total pressure of 1.3 Pa and microwave power of 50-800 W. On the other hand, CH3 radical density in the CH4 plasma was estimated to be less than 1010 cm-3. Moreover, the production and loss processes of CH3 radical in the CH3OH plasma were discussed on the basis of the results of emission intensity of Ar*, the absorption ratio of CH3OH molecule and the decay curve analysis of CH3 radical after termination of the discharge.