ANALYSIS OF IMPURITY ON COMPOUND SEMICONDUCTOR SUBSTRATE SURFACE THROUGH SECONDARY ION MASS SPECTROMETRY AND ANALYSIS OF IMPURITY IN AIR

摘要

PURPOSE: To analyze the impurity on the surface of a substrate in quantitatively with high precision by forming a cap layer having the same composition to that of a compound semiconductor substrate on the substrate and carrying out the secondary ion mass spectrometry. ;CONSTITUTION: A cap layer 3 which essentially has the same composition to that of a substrate 1 is formed on a compound seeconductor substrate 1, and the secondary ion mass spectrometry is carried out from the surface of the cap layer 3 at least to the interface between the cap layer 3 and the substrate 1. Further, a contaminating impurity layer 2 is formed on the substrate 1, and the thickness of the cap layer 3 is set to about 100-300μm in order to prevent the peak of the impurity which is obtained by the analysis from being too broad and prevent the initial effect from being suppressed insufficiently. Accordingly, the impurity on the surface of the substrate 1 can be analyzed quantitatively with high precision.;COPYRIGHT: (C)1993,JPO&Japio