Nanosecond laser-induced surface damage and its mechanism of CaF2 optical window at 248 nm KrF excimer laser

被引：18

作者：

Li, Xin ^{[1
,2
]}

Dou, Xian-an ^{[1
,2
]}

Zhu, Hong ^{[3
]}

Hu, Yue ^{[4
]}

Wang, Xi ^{[1
,2
]}

机构：

[1] Natl Univ Def Technol, State Key Lab Pulsed Power Laser Technol, Hefei 230037, Peoples R China

[2] Anhui Lab Adv Laser Technol, Hefei 230037, Peoples R China

[3] Army Artillery & Air Def Acad, Key Lab Polarizat Imaging Detect Technol Anhui Pr, Hefei 230037, Peoples R China

[4] Hefei Second Sanat Retired Cadres Anhui Prov Mil, Hefei 230061, Peoples R China

来源：

SCIENTIFIC REPORTS | 2020年 / 10卷 / 01期

关键词：

FUSED-SILICA; CRYSTALS; DEFECTS; PULSES; BULK;

D O I：

10.1038/s41598-020-62469-y

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Calcium fluoride (CaF2) crystals is a kind of important optical material for ultraviolet (UV) and deep-ultraviolet (DUV) lithography and high-power laser-related applications. However, its laser-induced damage threshold (LIDT) directly affects the laser power, so that the above-mentioned applications could be limited. Therefore, the research on the damage characteristics and laser damage resistance of CaF2 crystals is urgent. A 3D Finite-Difference Time-Domain (FDTD) method with Maxwell spinor equation is used, and the results show that the electric field intensity of rear surface is larger than that of front surface, which causes a lower threshold and is consistent with the experimental observations. And a thermo-mechanical coupled finite element model (FEM) of CaF2 with Ce2O3 impurities, which are introduced by polishing process, has semiquantitatively described the damage mechanism of CaF2 by 248 nm-excimer laser.

引用

页数：14