Luminescence of α-quartz crystal and silica glass under excitation of excimer lasers ArF (193 nm), KrF (248 nm)

Abstract

Luminescence of crystalline α-quartz and silica glass was studied under focused laser excitation. It was found that in crystalline α-quartz the luminescence of self-trapped exciton (STE) is excited in two-photon regime with ArF (193 nm) excimer laser. In the case of KrF (248 nm) laser excitation mainly luminescence related to near surface area is seen even without laser beam focusing. The near surface luminescence has an emission band similar to that of STE in bulk. Temperature quenching is also similar, therefore this luminescence is attributed to STE created in the area of surface. Luminescence decay kinetic of surface STE is longer than bulk STE decay (tens of ms compared to 1 ms at 80 K). Electron or/and hole selftrapping near the surface is assumed. Their recombination could provide longer duration of surface STE luminescence. Similar surface luminescence was not excited with ArF (193 nm) excimer laser. The nature of absorption for laser 248 nm photons at surface is not yet clear. Luminescence of silica glass of III type excited with focused beam of KrF (248 nm) laser resembles that of previously studied luminescence of STE in silica.

Laser-Induced Chemistry Observed during 248 nm Vacuum Ultraviolet Photolysis of an O3 and CH3NH2 Mixture

“…Following an interaction with UV light, quartz is known to luminesce in the blue from 300 to 700 nm, peaking around 450 nm. 27 This blue light emission from the tube is observed in our experiment with the naked eye and assists in experimentally aligning the laser onto the tube. Formaldehyde is known to photolyze at wavelengths above 300 nm.…”

Luminescence of localized states in oxidized and fluorinated silica glass

“…11 are practically independent of temperature, but their intensity decreases with increasing the tem-perature. This is indication of STE luminescence [18].…”

“…The relevant data are shown in Figure 17. It should be noted that the twophoton excitation by a KrF laser practically does not ensure STE emission in the bulk of α-quartz crystal sample, [18]. The STE luminescence was observed on the surface of the crystalline sample even in the single photon mode.…”

“…The creation of a red luminescent non-bridging center oxygen during irradiation is observed. Earlier [18], type III silica has been used to study the luminescence of self-trapped excitons (STE) under a two-photon excitation of a KrF (248 nm) laser due to the sup-pression of the ODC emission with OH. The relevant data are shown in Fig.…”

“…Thus, the nature of luminescence is at least partially different for KrF excitation, on the one hand, and F 2 and ArF lasers, on the other. We assume that a KrF laser can excite the luminescence of a self-trapped exciton (STE) in silica glass, as was obtained earlier [18].…”