用EBIC法观察InSb半导体器件中的p-n结

Applications of Electron Beam-induced Current at p-n Junction in InSb Devices

能够直观地“看到”半导体材料中制作的p-n结,对于半导体器件的设计和制造工艺很有意义,知道p-n结的厚度及其在样品中的位置,有利于设计器件的结构、保护膜的厚度、电极的尺寸等,也可以优化离子注入、表面处理、电路互联等工艺参数。本文用EBIC(电子束诱生电流)法观察了InSb半导体器件中的p-n结。同时观察到了器件中的肖特基结,其中肖特基结显示出明显的温度特性:温度降低,肖特基结响应区域扩大,温度降至80K,Cr-InSb肖特基结响应区域可扩展至47μm。用离子注入法在InSb材料中制成的p-n结其空间电荷区并不呈对称的空间分布,靠n区一侧的空间电荷区较薄,电荷密度较大,靠p区一侧的空间电荷区较厚,电荷密度相对较小。作为一种常用的观察分析工具,EBIC法在观察分析半导体器件结构方面有透视和显微等优点。

Being able to visually “see” a p-n junction in a semiconductor is advantageous to the design and fabrication of semiconductor devices.Electron beam-induced current (EBIC) was employed in this study to observe the p-n junction in InSb devices,and both Schottky and p-n junctions were observed through EBIC signal distribution.The Schottky junction response shows distinct temperature dependence: the response will extend with the temperature decrease.For a Cr-InSb device,the Schottky junction response extends to 47 mm at 80 K.The space charge region of the p-n junction fabricated using ion-beam injection in the InSb device has an asymmetrical spatial distribution.The aforementioned region on the n-type side is thinner and has larger charge density than that on the p-type side.As one of the most useful analytical methods,EBIC offers the advantage of a microscopic and perspective view for the observation and analysis of semiconductor devices.