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用正电子湮没技术和扫描电子显微镜研究了阳极氧化法制备的多孔硅材料。正电子湮没实验表明，随着阳极氧化时间的延长，平均寿命值增大，空位缺陷增多。长寿命（正电子素）成分较少。扫描电子显微镜显示，在阳极氧化过程中有尺寸为几um的单晶球形成。并观察到部分单晶球脱离后形成的微米坑。空位缺陷增多的原因可能是随着阳极氧化时间的延长，多孔硅结构向内层延伸增加了空位缺陷。但扫描电子显微镜的观察结果并不排除另一种可能：部分表面结构的变化增大了表面层的空位缺陷浓度。
The positron annihilation technique and scanning electron microscopy were used to study the porous silicon material prepared by anodic oxidation. Positron annihilation experiments show that with the anodic oxidation time, the average life expectancy increases, vacancy defects increased. Long life (positron) composition less. Scanning electron microscopy revealed the formation of single crystal spheres of several um in size during anodization. And observed the formation of micro-crater after the partial crystal ball detached. The reason for the increase of vacancy defects may be that as the anodization time prolongs, the porous silicon structure increases the vacancy defects to the inner layers. However, the observation by scanning electron microscopy does not exclude the possibility that the change in partial surface structure increases the concentration of vacancy defects in the surface layer.