Correlation between 193nm absorption and photoluminescence-related defects for fused silica materials

Abstract

We reported on the study of the correlation between 193nm absorption under 1.5~5.0mJ/cm2 fluence irradiation and photoluminescence (PL) related defects for deep-ultraviolet (DUV) fused silica samples with different H2 and OH contents (0~1200ppm). Experimental results showed strong correlations between apparent nonlinear absorption at 193nm to 650nm PL band originated from a non-bridging oxygen hole center (NBOHC), and between apparent linear absorption at 193nm to 550nm PL band. In addition, only 650nm PL defects showed reversible concentration change under 193nm laser irradiation, indicating a possible link to the rapid damage process (RDP) under DUV irradiation. Experimental observation and theoretical calculations on the dependence of 650nm PL intensity on the laser fluence further demonstrated that the generation and annealing processes of NBOHC in these DUV fused silica samples are mainly due to two-photon excitation induced breakage of SiOH bond and combination of NBOHC with H2. These results give new insight into the influence of NBOHC and SiOH on fused silica’s DUV absorption and transmission properties, and therefore are helpful to the development of high-performance DUV fused silica materials.