Overlay error measuring device and computer program
View Patent ↗The purpose of the present invention is to provide an overlay error measuring device for correcting a pattern displacement other than an overlay error to thereby achieve high-precision overlay error measurement. To accomplish the abovementioned purpose, the present invention proposes an overlay error measuring device which measures a dimension between a plurality of patterns belonging to different layers using a signal obtained by a charged particle beam device, and when measuring the dimension, corrects an amount corresponding to a pattern shift due to an optical proximity effect and measures the dimension between the plurality of patterns.
1. An overlay error measuring device having an arithmetic processing device for performing measurement of a pattern formed on a sample based on an image obtained by a charged particle beam device, wherein
the arithmetic processing device uses a signal obtained by the charged particle beam device to measure dimensions between a plurality of patterns belonging to different layers and, during the measurement of dimensions, corrects a pattern shift component due to an optical proximity effect to thereby execute dimension measurement between the plurality of patterns, and
the arithmetic processing device selects a symmetry pattern as the dimension measuring object pattern.
2. The overlay error measuring device according to claim 1 , wherein the arithmetic processing device executes dimension measurement between the plurality of patterns after having corrected a distance between two patterns constituting the symmetry pattern in such a way that it becomes the same as the symmetry pattern's layout data or simulation data.
3. The overlay error measuring device according to claim 1 , wherein the arithmetic processing device measures dimensions of a midpoint between two patterns constituting the symmetry pattern of layout data or simulation data and a midpoint between two patterns constituting the symmetry pattern of contour data to be generated based on a signal obtained by the charged particle beam device.
4. The overlay error measuring device according to claim 1 , wherein the arithmetic processing device executes the dimension measurement between the plurality of patterns based on a panorama image with a plurality of fields of view composed together.
5. The overlay error measuring device according to claim 4 , wherein the arithmetic processing device selects a symmetry pattern as the dimension measuring object pattern.
6. The overlay error measuring device according to claim 5 , wherein the arithmetic processing device causes the field of view to move in accordance with a shift of the symmetry pattern.
7. The overlay error measuring device according to claim 6 , wherein the arithmetic processing device moves the field of view in such a way that a predetermined edge is contained within a superimposed region between the plurality of fields of view.
8. A computer program for allowing a computer to execute measurement of patterns formed on a sample based on an image obtained by a charged particle beam device, wherein
the computer program causes the computer to use a signal obtained by the charged particle beam device to measure dimensions between a plurality of patterns belonging to different layers and to correct, during the measurement of dimensions, a pattern shift component due to an optical proximity effect to thereby execute dimension measurement between the plurality of patterns, and
the computer program causes the computer to select a symmetry pattern as the dimension measuring object pattern.