DOI QR코드

DOI QR Code

Optical Properties of DLC-coated ZnS Substrates in the Mid-infrared Region

중적외선 영역의 DLC 코팅된 ZnS 기판의 광학 특성

  • Kwon, Tae-Hyeong (Electronic Material & Center, Korea Institute of Ceramic Engineering & Technology) ;
  • Yeo, Seo-Yeong (Electronic Material & Center, Korea Institute of Ceramic Engineering & Technology) ;
  • Kim, Chang-Il (Electronic Material & Center, Korea Institute of Ceramic Engineering & Technology) ;
  • Nahm, Sahn (Department of Materials Science and Engineering, Korea University) ;
  • Kwon, Min-Chul (UNIVAC LTD.) ;
  • Chu, Byoung-Uck (AVAS Co.) ;
  • Paik, Jong-Hoo (Electronic Material & Center, Korea Institute of Ceramic Engineering & Technology)
  • Received : 2019.02.08
  • Accepted : 2019.03.22
  • Published : 2019.03.31

Abstract

ZnS substrates with excellent transmittance in the mid-infrared region ($3-5{\mu}m$) were prepared using hot pressing instead of conventional chemical vapor deposition (CVD). Diamond-like carbon(DLC) was coated on either one or both sides of the ZnS substrates to improve their mechanical properties and transmittance. More specifically DLC was coated using CVD with an Ar and $C_2H_2$ mixed gas, and Ge was used as the bonding layer. During CVD, the bias voltage was fixed to 500 V and analyzed by Fourier transform infrared spectroscopy (FT-IR), nanoindenter, scanning electron microscope and energy dispersive spectrometry. Results of hardness analysis using the nanoindenter, showed that DLC coating increased from 5.9 to 17.7 GPa after deposition. The FT-IR spectroscopy results showed that, in the mid-infrared region ($3-5{\mu}m$), the average transmittance of the samples with DLC coating on one and both sides increased by approximately 6% and approximately 11.2% respectively. In conclusion, the DLC coating improved the durability and transmittance of the ZnS substrates.

Keywords

HSSHBT_2019_v28n2_101_f0001.png 이미지

Fig. 1. Schematic diagram of the experimental process.

HSSHBT_2019_v28n2_101_f0002.png 이미지

Fig. 2. SEM images of the DLC coated ZnS substrate suface; (a) 420 nm, (b) 540 nm, (c) 650 nm, (d) 720 nm, (e) 850 nm of thickness (× 30k).

HSSHBT_2019_v28n2_101_f0003.png 이미지

Fig. 3. SEM images of the DLC coated ZnS substrate fracture; (a) 420 nm, (b) 540 nm, (c) 650 nm, (d) 720 nm, (e) 850 nm of thickness (× 30k).

HSSHBT_2019_v28n2_101_f0004.png 이미지

Fig. 4. EDS images of the DLC coated ZnS substrate fracture.

HSSHBT_2019_v28n2_101_f0005.png 이미지

Fig. 5. Nanoindenter load-displacement curves for uncoated ZnS substrate, single side DLC coated.

HSSHBT_2019_v28n2_101_f0006.png 이미지

Fig. 6. Infrared transmittance of single side DLC coated ZnS substrate various thickness.

HSSHBT_2019_v28n2_101_f0007.png 이미지

Fig. 7. Infrared transmittance of both sides DLC coated ZnS substrate various thickness.

Table 1. Transmittance of single side DLC coated ZnS substrate by thickness

HSSHBT_2019_v28n2_101_t0001.png 이미지

Table 2. Transmittance of both sides DLC coated ZnS substrate by thickness

HSSHBT_2019_v28n2_101_t0002.png 이미지

References

  1. Y. Li and Y. Wu, "Transparent and luminescent ZnS ceramic consolidated by vacuum hot pressing method", J. Am. Ceram. Soc., Vol. 98, No. 10, pp. 2872-2975, 2015.
  2. S. Y. Yeo, T. H. Kwon, C. I. Kim, J. S. Yun, Y. H. Jeong, Y. W. Hong, J. H. Cho, and J. H. Paik, "Structural properties of ZnS nanoparticles by hydrothermal synthesis process conditions and optical properties of ceramic", J. Korean Inst. Electr. Electron. Mater. Eng., Vol. 31, No. 5, pp. 392-397, 2018.
  3. S. Y. Yeo, T. H. Kwon, C. S. Park, C. I. Kim, J. S. Yun, Y. H. Jeong, Y. W. Hong, J. H. Cho, and J. H. Paik, "Sintering and optical properties of transparent ZnS ceramics by pre-heating treatment temperature", J. Electroceram. Vol. 41, No. 1-4, pp. 1-8, 2018.
  4. X. Fang, T. Zhai, U. K. Gautam, L. Li, L. Wu, Y. Bando, and D. Golberg, "ZnS nanostructures: From synthesis to applications", Prog. Mater. Sci., Vol. 56, No. 2, pp. 175-287, 2011. https://doi.org/10.1016/j.pmatsci.2010.10.001
  5. G. F. Zhang, and X. Zheng, "Optical transmittance of antireflective diamond-like coatings on ZnS substrates", Sur. Coat. Technol., Vol. 82, No. 1-2, pp. 110-113, 1996. https://doi.org/10.1016/0257-8972(95)02655-X
  6. Q. He, H. B. Guo, J. J. Wei, S. J. Askari, H. B. Wang, S. Y. Zhang, H. Yang, X. P. Su, and F. X. Lu, "Deposition of $HfO_2$ thin films on ZnS substrates", Thin Solid Films, Vol. 516, No. 15, pp. 4695-4699, 2008. https://doi.org/10.1016/j.tsf.2007.08.060
  7. C. Hu, W. Zheng, H. tian, L. Xu, and Q. Jiang, "Effects of the chemical bonding on the optical and mechanical properties for germanium carbide films used as antireflection and protection coating of ZnS windows", Condens. Matter., Vol. 8, No. 17, pp. 4231-4241, 2006.
  8. C. R. Lin, D. H. Wei, C. K. Chang, and W. H. Liao, "Optical propeties of diamond-like carbon films for antireflection coating by RF magnetron sputtering method", Phys. Procedia, Vol. 18, pp. 46-50, 2011. https://doi.org/10.1016/j.phpro.2011.06.055
  9. G. F. Zhang, L. J. Guo, Z. T. Liu, X. K. Xiu, and X. Zheng, "Studies on diamond like carbon films for antireflection coatings of infrared optical materials", J. Appl. Phys., Vol. 76, No. 2, pp. 705-707, 1994. https://doi.org/10.1063/1.357813
  10. P. Manivel, S. Ramakrishnan, N. K. Kothurkar, N. Ponpandian, D. Mangalaraj, and C. Viswanathan, "Graphene nanosheets by low-temperature thermal reduction of graphene oxide using RF-CVD", J. Exp. Nanosci., Vol. 8, No. 3, pp. 1-9, 2012.
  11. E. Dervishi, A. R. Biris, Joshua A. Driver, Fumiya Watanabe, Shawn Bourdo, and Alexandru S. Biris, "Low-temperature ($150^{\circ}C$) carbon nanotube growth on a catalytically active iron oxide-graphene nano-structural system", J. Catal., Vol. 299, pp. 307-315, 2013. https://doi.org/10.1016/j.jcat.2012.12.013
  12. M. Gilo, and A. Azran, "Low reflectance DLC coatings on various IR substrates", Proc. SPIE, Vol. 8353, No. 835320, pp. 20-28, Baltimore, USA, 2012.
  13. R. Zarei Moghadam, H. Ahmadvand, and M. Jannesari, "Design and fabrication of multi-layers infrared antirlection coating coasisting of ZnS and Ge on ZnS substrate", Infrared Phy. Technol., Vol. 75, pp. 18-21, 2016. https://doi.org/10.1016/j.infrared.2015.12.028
  14. Johannes J. Moes, Marco M. Ruijken, Erik Gout, Henderik W. Frijlink, and Michael I. Ugwoke, "Application of process analytical technology in tablet process development using NIR spectroscopy : Blend uniformity, cotent uniformity and coating thickness measurements", Int. J. Pharm., Vol. 357, No. 1-2, pp. 108-118, 2008. https://doi.org/10.1016/j.ijpharm.2008.01.062