Patent ID: 8044352

Claim:
A charged particle beam device, comprising: a charged-particle source; a deflector that scans a specimen with a primary charged particle beam discharged from the charged-particle source; an objective lens that converges the primary charged particle beam discharged from the charged-particle source; a detector that detects backscattered electrons generated from the specimen by irradiation with the primary charged particle beam, detection elements of the detector being arranged in a plane; a memory that stores signals from the detector by associating each irradiation position with corresponding distribution information of the detected backscattered electrons generated at said each irradiation position; and a control unit that forms an image from the stored signals from the detector by calculating a value for each pixel of the image using a predetermined region of the distribution information of the detected backscattered electrons for the corresponding irradiation position, wherein the control unit compares the distribution information for all of the irradiation positions, modifies each distribution information by subtracting a signal common to each distribution information therefrom, and calculates said value for each pixel based on the modified distribution information for the corresponding irradiation position.