Inspection method and inspection system using charged particle beam

Abstract

Secondary electrons and back scattered electrons generated by irradiating a wafer to be inspected such as a semiconductor wafer with a charged particle beam are detected by a detector. A signal proportional to the number of detected electrons is generated, and an inspection image is formed on the basis of the signal. On the other hand, in consideration of a current value and irradiation energy of a charged particle beam, an electric field on the surface of the inspection wafer, emission efficiency of the secondary electrons and back scattered electrons, and the like, an electric resistance and an electric capacitance are determined so as to coincide with those in the inspection image. In a state where a difference between a resistance value in a normal portion and a resistance value in a defective portion is sufficiently increased by using the charging generated by the irradiation of electron beams, an inspection is conducted to thereby detect a defect.

1 . An inspection method using charged particle beam, comprising:
 a step of scanning a region in a surface of a wafer in which an electric resistance value of a circuit pattern has dependency on voltage with a primary charged particle beam;   a step of detecting signals of secondary electrons and back scattered electrons generated from said region which is irradiated with said primary charged particle beam;   a step of forming an image of said region from the detected signals of said secondary electrons and back scattered electrons; and   a step of analyzing a contrast of said image in the region irradiated with said primary charged particle beam on the basis of parameters of irradiating said primary charged particle beam and parameters of detecting secondary electrons and back scattering electrons, and determining an electric resistance and an electric capacity.