Scanning electron microscope device and pattern dimension measuring method using same

摘要

In a panoramic image construction technology a wide-range imaging area (EP) of semiconductor patterns is divided into a plurality of imaging areas (SEP), and joined a group of images, which are obtained by imaging the SEPs using an SEM, through image processing. Although a pattern serving as a key to joining is not contained in an overlap area between some of the SEPs, all the images can be joined in some cases is noted so that: although the number of patterns serving as keys to joining is small, SEPs whose images are all joined can be determined; or even if such SEPs cannot be determined, SEPs satisfying user's request items as many as possible can be determined. The cases are extracted by optimizing an SEP arrangement, whereby the number of cases in which SEPs whose images are all joined can be determined is increased.

主权项

1. A scanning electron microscope device comprising:
a scanning electron microscope; an imaging recipe composer configured to compose an imaging recipe for imaging a specimen, which has patterns formed on the surface thereof, using the scanning electron microscope; an image processor configured to process an image of the specimen, which is obtained by imaging the specimen using the scanning electron microscope, on the basis of the imaging recipe composed by the imaging recipe composer; a dimensional information extractor configured to extract dimensional information on a pattern, which is formed on the specimen, from the image of the specimen processed by the image processor; an input/output unit that includes a display screen and inputs or outputs information configured to be processed by the image processor and dimensional information extractor and information processed thereby; and a controller configured to control the microscope, imaging recipe composer, image processor, dimensional information extractor, and input/output unit, wherein the imaging recipe composer configured to calculate first index values between adjacent overlapping imaging areas, which indicate propriety or ease of joining between the adjacent overlapping imaging areas which are divided from a high-magnification image acquisition area by using design information on the high-magnification image acquisition area designated on a low-magnification image of the specimen picked up by the scanning electron microscope and to calculate second index values between non-adjacent imaging areas using the first index values which indicate propriety or ease of joining of two arbitrary local imaging areas, and composing an imaging recipe using the calculated first and second index values, wherein the controller configured to control the scanning electron microscope so as to allow the scanning electron microscope to image the local imaging areas at a high magnification on the basis of the imaging recipe composed by the imaging recipe composer, wherein the image processor configured to produce a high-magnification wide-area image by joining the high-magnification images of the local imaging areas picked up by the scanning electron microscope; and wherein the dimensional information extractor configured to extract a dimension of the pattern from the high-magnification wide-area image produced by the image processor, and wherein the imaging recipe composer configured to determine propriety or ease of joining of two arbitrary local imaging areas from a line segment length of the pattern contained in an overlap area between the two arbitrary adjoining local imaging areas.