ArF laser induced pulse absorption in fused silica (type III): Modeling the fluence and repetition rate dependence

Accurate Determination of the Low-Light-Level Absorption of DUV-Fused Silica at 193 nm with Laser Calorimetry

“…In addition, E' centers, which have no 193 nm-excited fluorescence band in the 200~800 nm spectral range, are believed to be the major source to the 193 nm absorption [17]. In the DUV fused silica material the E' centers are produced by the 193 nm laser irradiation induced breaking of the strained Si-O-Si bonds [17,29] and annealed by the impregnated H2 [30].…”

“…Fluorescence bands related to ODC (290 nm and 320 nm bands), peroxide radical (POR) (390 nm band), and NBOHC (650 nm band), as well as a 550 nm band of unknown defects which is believed to be related to the strained bonds [28], are present. In addition, E' centers, which have no 193 nm-excited fluorescence band in the 200~800 nm spectral range, are believed to be the major source to the 193 nm absorption [17]. In the DUV fused silica material the E' centers are produced by the 193 nm laser irradiation induced breaking of the strained Si-O-Si bonds [17,29] and annealed by the impregnated H 2 [30].…”

“…In addition, E' centers, which have no 193 nm-excited fluorescence band in the 200~800 nm spectral range, are believed to be the major source to the 193 nm absorption [17]. In the DUV fused silica material the E' centers are produced by the 193 nm laser irradiation induced breaking of the strained Si-O-Si bonds [17,29] and annealed by the impregnated H 2 [30]. Taking into consideration the surface absorption, the intrinsic and defect-related linear and nonlinear absorption, as well as the generation and annealing of the absorptionrelated defects, the absorptance of the DUV-fused silica sample measured by the LCA instrument can be expressed as [17].…”

“…when the laser fluence H keeps constant and the repetition rate f changes. In Equations ( 3) and ( 4), As is the surface absorption, d is the sample thickness, and α0 and β0 are the linear Taking into consideration the surface absorption, the intrinsic and defect-related linear and nonlinear absorption, as well as the generation and annealing of the absorption-related defects, the absorptance of the DUV-fused silica sample measured by the LCA instrument can be expressed as [17].…”

“…However, in absorption measurement with LCA, LID or WFS in which an ArF excimer laser is used as the irradiation light source, the measured absorption normally includes the contributions from the surface absorption, the linear absorption, the nonlinear or twophoton absorption, and defect-related absorption [6,15,16]. Some of these contributions are irradiation fluence and repetition rate dependent [17]. To obtain the internal transmission related low-light-level linear absorption, these absorptions have to be separated.…”