The Ag ions were implanted in an amorphous SiO2 film, which was placed in a sample chamber of TEM. The concentration and size distribution of the Ag nanocrystals as functions of both the ion dose and the annealing temperature were examined in-situ by using this TEM. The selected diffraction pattern determined the Ag nanocrystal's presence and the dark field micrograph showed the shape and the concentration of the Ag nanocrystals. The implantation results demonstrated an average size diminution and a significant concentration increase of the Ag nanocrystals when the dose increased. The annealing results showed a loss of silver at 300℃ and above.

A new detection system in scanning electron microscope, which filters in energy and detects the backscattered electrons close to the microscope axis, is described. This technique ameliorates the dependence of the backscat-tering coefficient on atomic number, and suppresses effectively the relief contrast at the same time. Therefore this new method is very suitable to the composition analysis.

We simulate the trajectories of backscattered electrons within a SEM of particular detection geometry which is adapted to topographic contrast attenuation and Z atomic number contrast enhancement. The calculations are performed choosing the different experimentally possible conditions as regards the primary electron energy, the detector aperture angle and the energy window of the detected electrons. From such simulations, it is possible to deduce the backscattering coe

采用MEVVA源（metal vapor vacuum arc ion source）引出的强束流脉冲Ag，Cu离子先后注入到SiO2玻璃，x射线光电子能谱仪（XPS）分析显示Ag，Cu大多仍为金属态,有部分氧化态Cu存在。透射电镜观察分析和光学吸收谱都表明在衬底中形成了纳米合金颗粒。结合有效媒质理论,得到模拟的光学吸收谱，与实验结果基本符合，较好地验证了以上结论。样品退火后颗粒发生分解，分解的颗粒在氧化气氛下被氧化，且有部分向样品表面蒸发；在还原气氛下氧化态元素被还原并成核生长。故可通过改变退火条件对纳米颗粒的成核生长进行调制。

能量为200keV的Ag离子，以1×1016，5×1016，1×1017cm-2的剂量分别注入到非晶SiO2玻璃，光学吸收谱显示：注入剂量为1×1016cm-2的样品的光吸收谱为洛伦兹曲线，与Mie理论模拟的曲线形状一致；注入剂量较大的5×1016，1×1017cm-2的谱线共振吸收增强，峰位红移并出现伴峰。透射电镜观察分析表明，注入剂量不同的样品中形成的纳米颗粒的大小、形状、分布都不同，注入剂量较大的还会产生明显的表面溅射效应，这些因素都会影响共振吸收的峰形、峰位和峰强。当注入剂量达到1×1017cm-2时，Ag纳米颗粒内部可能还形成了杂质团簇。