[1 ] G.K.Wehner: APPI. Pbys. Lett., 1977, 30, 185;R.R.olson, M.E.King and G.K-Wehner: J. Appl.Phys ., 1979, 50, 3677. [2 ] W.A.Russell, D.A.Papanastassiou and T.A.Tombrello:Radiat. EE, 1980, 52, 41. [3 ] P.Sigmund: Nud- Instz. and Meth-, 1987, B18, 375. [4 ] M.H.Shapiro, T.A.Tombrello and D.E.Harrison Jr:Nuc;. ID str. and Meth., 1988, B30, 152. [5 ] W.Eckstein and J.P.Biersack: APp1- Pfor., 1985,A37, 95. [6 ] H.Gnaser and H-Oechsner: Nuc1. IDstr. and Meth.,1990, B48, 544. [7 ] L.P.Zheng, R.S.Li, M.Y.Li, J.Y.Lin and Z.Y.Zou:Nud. IDs tI. and Metb., 1991, B62, 61. [8 ] D.L.Weathers, S.J.Spicldemire, T.A.Tombrello,I.D.Hutcheon and H-Gnaser: Nuc1. ID str. and Metb.,1993, B73, 135. [9 ] W.Eckstein: Nuc1. ID str. and Metb., 1993, B83, 329. [10] L.P-Zheng and F.Z.Cul: Chill. Pbys. Lett., 1995, 12,431. [11] P.Sigmund and M.W.Sckerl: Nud. Instr. and Meth.,1993, B82, 242. [12] P.Sigmund: Nuc1. fustr. and Metb,, 1993, B82, 192. [13] D.L.Weathers, I-D.Hutcheon, H.Gnaser, T.A.Tombrelloand M.H.Shapiro: NucI. Instr- and Meth., 1993, B82,194. [14] L.P.Zheng, R.S.Li and M.Y.Li: Nucl. Instr. andMeth, 1995, B100, 490. |