1. Y. Oka, T. Shoji, T. Kuroda, et al., Rev. Sci. Instrum. 61, 1256 (1990).
2. Y. Hakamata, T. Iga, K. Natsui, and T. Sato, Nucl. Instrum. Methods Phys. Res. B 37-38, 143 (1989).
3. V. Ya. Martens, S. I. Belyuk, and V. N. Posokhov, Prib. Tekh. Éksp., No. 2, 194 (1992).
4. A. V. Vizir’, E. M. Oks, P. M. Shchanin, and G.Yu. Yush-kov, Zh. Tekh. Fiz. 67(6), 28 (1997) [Tech. Phys. 42, 611 (1997)].
5. A. S. Metel’, Zh. Tekh. Fiz. 54, 241 (1984) [Sov. Phys. Tech. Phys. 29, 141 (1984)].