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We have demonstrated the photon-stimulated surface spectroscopy using broadband vacuum ultraviolet (VUV) emissions from a laser-produced plasma, in which adsorbed atoms or molecules on material surfaces were to be desorbed and dissociated as a result of absorption of the wavelength-selected VUV photons. Desorbed and dissociated atoms or molecules were then detected by a mass spectrometer. Mass spectra of polyethylene and polyvinyl chloride samples were obtained as a function of the irradiation wavelength. We have found sufficient characteristic differences of the mass spectra in the irradiation wavelength shorter than 200 nm in each sample. The desorption and dissociation of atoms or molecules from material surfaces depended on bond energy or molecular structure.

Silica film coatings were demonstrated using photo-chemical vapor deposition with a 172-nm Xe excimer lamp. Tetraethoxyorthosilicate (TEOS) molecules were successfully dissociated into SiO2+2C2H5-OH+;(residual C and H) with the 7.2-eV photons. The films were deposited onto a quartz or Al203 single crystal substrate with the deposition rate of 1 nm/min. The films were uniform and smooth enough for optical applications.

An excimer lamp is a new light source which can produce shorter wavelength of vacuum ultraviolet radiation than conventional ArF excimer lasers. We have tried to use the excimer lamp for photo-etching of polymers such as polymethylmetacrylie and polyimidic resins. We have found that the etching process was including the chemical and the quantumn processes. We also applied this technique for etching of some single crystalline organic materials which were very important to opt-electronic applications.

The argon excimer laser provides 9.8-eV photons that readily surmount the electronic bandgap energy of SiO2 (∼9.0 eV), directly generating excitons in a single-photon absorption process. We have shown by Si L2,3 (Si 3s→2p) X-ray emission spectroscopy, Si 2p X-ray photoelectron spectroscopy and Raman spectroscopy that this absorption process is responsible for silicon precipitation in the silica. The X-ray emission studies further show that the silicon precipitates are crystalline, forming in highest concentration in 120–230 nm layer beneath the laserirradiated surface. Silicon precipitation was not observed on samples irradiated with 146-nm krypton excimer radiation due to a smaller 8.5-eV photon energy that is below the silica bandgap.