Pattern inspection method, pattern inspection apparatus, semiconductor device manufacturing method, and program

A semiconductor device manufacturing method comprising executing a process of manufacturing a semiconductor device on a substrate when a pattern to be inspected on the substrate for fabrication of the semiconductor device is judged to satisfy required specifications of the semiconductor device as a result of an inspection by a pattern inspection method, the pattern inspection method comprising:

• measuring a pattern to be inspected, including:
• irradiating with a charged particle beam a first region of a surface of a sample having the pattern to be inspected formed therein,
• acquiring a first two-dimensional image showing a state of the surface of the sample by detecting at least one of a secondary charged particle, a reflection charged particle, and a back scattering charged particle emitted from the sample due to the irradiation of the first region with the charged particle beam,
• searching, within the first two-dimensional image, for a first pattern similar to a previously prepared reference image, and
• when the first pattern similar to the reference image is detected at a first place within the first two-dimensional image, focusing the charged particle beam at a second place that is different from the first place, acquiring a second two-dimensional image magnified higher than the first two-dimensional image at the first place;
• and
• further measuring the pattern to be inspected when the first pattern similar to the reference image is not detected in the first two-dimensional image, the further measuring including:
• irradiating with the charged particle beam a second region of the surface of the sample that has not been irradiated,
• acquiring a third two-dimensional image showing a state of the surface of the sample by detecting at least one of a secondary charged particle, a reflection charged particle, and a back scattering charged particle emitted from the sample due to the irradiation of the second region with the charged particle beam,
• searching, within the third two-dimensional image, for a second pattern similar to the reference image,
• when the second pattern similar to the reference image is detected at a third place within the third two-dimensional image, focusing the charged particle beam at a fourth place that is different from the third place, acquiring a fourth two-dimensional image magnified higher than the third two-dimensional image at the third place.

A pattern inspection apparatus comprising:

• a charged particle beam source which generates a charged particle beam to irradiate a surface of a sample having a pattern to be inspected formed thereon;
• a focal position adjuster which adjusts the focal position of the charged particle beam;
• a beam position controller which adjusts a positional relation between the sample and the charged particle beam in a manner that a desired position on the sample is irradiated with the charged particle beam;
• a detector which detects at least one of a secondary charged particle, a reflection charged particle and a back scattering charged particle emitted from the sample due to the irradiation of the surface of the sample with the charged particle beam to output data on a first two-dimensional image showing a state of the surface of the sample;
• a pattern recognizer which uses a previously prepared reference image to detect a pattern similar to the reference image within the first two-dimensional image, and outputting information on the position of the detected pattern as information on the position of the pattern to be inspected;
• and
• a controller which performs an initial measurement of the pattern to be inspected in a first region of the surface of the sample and performs a further measurement when no pattern similar to a previously prepared reference image is detected within a first two-dimensional image of the first region of the surface of the sample,
• wherein in the initial measurement the controller:
• controls the charged particle beam source to irradiate with the charged particle beam the first region of the surface of the sample, to acquire a first two-dimensional image showing a state of the first region of the surface of the sample based on data from the detector;
• controls the pattern recognizer to search within the first two-dimensional image for a first pattern similar to the reference image;
• when the first pattern similar to the reference image is detected by the pattern recognizer at a first place within the first two-dimensional image, controls the beam position controller and the focal position adjuster to focus the charged particle beam at a second place that is different from the first place;
• controls the beam position controller, the charged particle source, and the detector to acquire a second two-dimensional image magnified higher than the first two-dimensional image at the first place and to measure the pattern to be inspected, and
• wherein in the further measurement the controller:
• controls the charged particle beam source to irradiate with the charged particle beam a second region of the surface of the sample that has not been irradiated, acquiring a third two-dimensional image showing a state of the second region of the surface of the sample based on data from the detector;
• controls the pattern recognizer to search within the third two-dimensional image for a second pattern similar to the reference image;
• when the second pattern similar to the reference image is detected by the pattern recognizer at a third place in the third two-dimensional image, controls the beam position controller and the focal position adjuster to focus the charged particle beam at a fourth place that is different from the third place;
• controls the beam position controller, the charged particle source, and the detector to acquire a fourth two-dimensional image magnified higher than the third two-dimensional image at the third place back from the fourth place and to measure the pattern to be inspected.