The Thickness Dependence of Optical Constants of Ultrathin Iron Films
GAO Shang1, LIAN Jie1**, SUN Xiao-Fen2, WANG Xiao1, LI Ping1, LI Qing-Hao3
1 Department of Optical Engineering, Shandong University, Jinan 250100 2Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 3School of Physics and Microelectronics, Shandong University, Jinan 250100
Abstract：Ultrathin iron films with different thicknesses from 7.1 to 51.7 nm are deposited by magnetron sputtering and covered by tantalum layers protecting them from being oxidized. These ultrathin iron films are studied by spectroscopic ellipsometry and transmittance measurement. An extra tantalum film is deposited under the same sputtering conditions and its optical constants and film thickness are obtained by a combination of ellipsometry and transmission measurement. After introducing these obtained optical constants and film thickness into the tantalum-iron film, the optical constants and film thicknesses of ultrathin iron films with different thicknesses are obtained. The results show that combining ellipsometry and transmission measurement improves the uniqueness of the obtained film thickness. The optical constants of ultrathin iron films depend strongly on film thicknesses. There is a broad absorption peak at about 370 nm and it shifts to 410 nm with film thickness decreasing.
. [J]. Chin. Phys. Lett., 2013, 30(2): 27801-027801.
GAO Shang, LIAN Jie, SUN Xiao-Fen, WANG Xiao, LI Ping, LI Qing-Hao. The Thickness Dependence of Optical Constants of Ultrathin Iron Films. Chin. Phys. Lett., 2013, 30(2): 27801-027801.
2013, Vol. 30 
