扫描光荧光表征半导体材料特性

A SYSTEM FOR CHARACTERIZATION OF SEMICONDUCTOR MATERIALS USING SCANNING PHOTOLUMINESCENCE

报道了一个自制的采用计算机控制的自动光荧光(PL)扫描系统.该系统可用于形貌半导体晶片或外延层的PL强度分布,尺寸可大到3英寸,样品可以是Si,GaAs,InP等.它可以用来探测材料中的缺陷及浅能级杂质,显示其分布.PL对于杂质识别和缺陷分布的形貌特别灵敏.文中列举和讨论了用本PL扫描系统对Si和GaAs所获得的一些光谱和形貌的信息.实验证明该系统可用作为一个简单、无接触然而却是灵敏的表征手段,可用于评估半导体基片近表面层的均匀性,也适用于器件表征.

In this study, the authors describe a computer-controlled scanning photoluminesoenoe (PL) system which has been designed for mapping PL intensities of semiconductor wafers or epitaxial layers up to 3 inches in diameter. Sample materials included Si, GaAs and so on. It can be used for investigation to detect defects and shallow impurities, and to show their distributions in semiconductor materials. PL is paiticularly sensitive for identifying impurities and mapping wafers to determine the distribution of defect densities over the surface of a wafer. Information from spectra and wafer maps is presented and discussed. The present scanning PL technique can be used as a simple, nondestructive, but sensitive tool in evaluating the uniformity of the near-surface layer of semioonduotor substrates and, therefore, is ideally suited for device characterization.