扫描电镜(SEM)具有多种成像模式,二次电子像和背散射电子像是最常用的模式。这两种像的衬度均与试样—检测器的几何位置有关,具有不同程度的阴影效应。吸收电流像与试样—检测器的几何位置无关,无阴影效应。对均匀的电惰性材料,吸收电流像与发射电流像(二次电子像和背散射电子像)的衬度互补。对半导体和磁性材料,没有这种互补关系。本文根据吸收电流像的特点,对均匀电惰性材料用吸收电流信号作为附加模式,用两次曝光技术对二次电子像中不易得到的形貌细节补偿,获得了清晰的图像。图1—4是对黄铜试样垫上的激光孔补偿前后的对比。我们还用吸收电流像观察了多相合金表面成份分布和半导体材料中的势垒电子伏特效应。实验结果表明吸收电流像主要有以下几种应用: Scanning electron microscopy (SEM) has a variety of imaging modes, and secondary and backscattered electron images are the most common modes. The contrast between the two images is related to the geometry of the sample-detector with varying degrees of shadowing. Absorption current is not related to the sample-detector geometry, with no shadow effect. For a uniform electrically inert material, the absorption current is complementary to the contrast of the emission current image (secondary electron image and backscattered electron image). For semiconductors and magnetic materials, there is no such complementary relationship. According to the characteristics of absorption current image, this paper absorbs the current signal of uniform electroless material as an additional mode, and uses the double exposure technique to compensate the difficult to obtain topography details in the secondary electron image, obtaining a clear image. Figure 1-4 shows the contrast of the laser hole on the brass sample pad before and after compensation. We also observed the distribution of heterogeneous alloy surface composition and the barrier electron-volt effect in semiconductor materials using absorption current. The experimental results show that the absorption current like the following applications: