[7] [7] Wang Y, Zhang Y, Chen W, et al. Optical Properties and Residual Stress of YbF3 Thin Films Deposited at Different Temperatures[J]. Applied optics, 2008, 47(13): 319-323.

[8] [8] Schnellbuegel A, Hagedorn H, Anton R. Ion-assisted Deposition of Nontoxic Coatings for High-power CO2 Laser Optics[C]. SPIE, 1994, 2253: 839-849.

[9] [9] Robic J Y, Muffato V, Chaton P, et al. Optical and Structural Properties of YF3 Thin Films Prepared by Ion-assisted Deposition or Ion Beam Sputtering Techniques[C]. SPIE, 1994, 2253: 195-208.

[10] [10] Gibson D R, Brinkley I, Waddell E M, et al. Closed Field Magnetron Sputtering: New Generation Sputtering Process for Optical Coatings[C]. SPIE, 2008, 7101: 710108.

[11] [11] Donovan T M, Temple P A, Wu S C, et al. The Relative Importance of Interface and Volume Absorption by Water in Evaporated Films[C]. Boulder: the Tenth ASTM Symposium on Laser Induced Damage in Optical Materials, 1980: 237-246.