Ion-induced kinetic electron emission from ~6LiF,~7LiF and MgF_2 thin films

作     者：S.Ullah A.H.Dogar M.Ashraf A.Qayyum 

作者机构：Pakistan Institute of Engineering and Applied SciencesNiloreIslamabadPakistan Physics DivisionPakistan Institute of Nuclear Science and TechnologyP.O.NiloreIslamabadPakistan Optics LaboratoriesP.O.Box 1021IslamabadPakistan 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2010年第19卷第8期

页      面：344-349页

核心收录：

学科分类：080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：Project partially supported by the Higher Education Commission of Pakistan through indigenous PhD program 

主　　题：ion-induced electron emission alkali halides electronic stopping electron mean free path 

摘      要：Secondary electron yields for Ar^＋ impact on 6LiF, 7LiF and MgF2 thin films grown on aluminum substrates are measured each as a function of target temperature and projectile energy. Remarkably different behaviours of the electron yields for LiF and MgF2 films are observed in a temperature range from 25 ℃ to 300 ℃. The electron yield of LiF is found to sharply increase with target temperature and to be saturated at about 175 ℃. But the target temperature has no effect on the electron yield of MgF2. It is also found that for the ion energies greater than 4 keV, the electron yield of 6LiF is consistently high as compared with that of 7LiF that may be due to the enhanced contribution of recoiling 6Li atoms to the secondary electron generation. A comparison between the electron yields of MgF2 and LiF reveales that above a certain ion energy the electron yield of MgF2 is considerably low as compared with that of LiF. We suggest that the short inelastic mean free path of electrons in MgF2 can be one of the reasons for its low electron yield.