Semiconductor evaluation device and computer program
The present invention provides a semiconductor evaluation device for fabricating a suitable reference pattern utilized in comparison tests. The semiconductor evaluation device and computer program extract a process window in a more accurate range based on a two-dimensional evaluation of the pattern. In order to achieve the above described objects, the present invention includes a semiconductor evaluation device that measures the dimensions of the pattern formed over the sample based on a signal obtained by way of a charged particle beam device, selects a pattern whose dimensional measurement results satisfy specified conditions or exposure conditions when the pattern is formed, and forms synthesized contour data, by synthesizing contour data obtained from images of an identically shaped pattern in design data, and also a pattern formed under the selected exposure conditions or a pattern having a positional relation that is already known relative to the selected pattern.
1. A system comprising:
a charged particle beam irradiation tool, including:
a stage configured to support a wafer; and
a controller communicatively coupled to the charged particle beam irradiation tool, the controller including a processor, wherein the processor is configured to execute a program instruction stored in memory, the program instruction configured to cause the controller to:
control the charged particle beam irradiation tool and the stage to perform a one-dimensional measurement of a plurality of patterns that have a same shape as each other and are exposed under different exposure conditions including a dose quantity and a focus value that are selected for the one-dimensional measurement;
determine a coordinate of a pattern having a dimension value which is equal to a stored dimension value, or the coordinate of the pattern having a dimension value within a predetermined range of dimension values including the stored dimension value;
control the charged particle beam irradiation tool and the stage to generate images of the plurality of patterns of the same shape exposed under a same exposure condition as the determined coordinate, or under a first exposure condition of a first area adjacent to a second area exposed by the first exposure condition as the determined coordinate;
extract a contour by an image processing for each of the images, and synthesize the extracted contours to generate a synthesized contour; and
evaluate the patterns included in the images using the synthesized contour.
2. The system according to claim 1 ,
wherein the processor includes a storage medium that stores a tolerance range of a shape evaluation parameter of a reference pattern, and extracts a range of a second exposure condition for a pattern contained within the tolerance range.
3. The system according to claim 2 ,
wherein the processor selects an overlapped range for a range of the first exposure condition, and the range of the second exposure condition.
4. The system according to claim 1 ,
wherein the processor selects a pattern whose dimensional measurement results satisfy specified conditions or exposure conditions by which the pattern is formed, based on dimensional measurements made for the plurality of patterns having different exposure conditions.
5. A non-transitory computer-readable medium storing a program operating on a computer that scans a plurality of patterns formed with different exposure conditions by an exposure apparatus to obtain images from a charged particle beam irradiation tool, including a stage configured to support a wafer, the program performing instructions comprising:
controlling the charged particle beam irradiation tool and the stage to perform a one-dimensional measurement of a plurality of patterns that have a same shape as each other and are exposed under different exposure conditions including a dose quantity and a focus value that are selected for the one-dimensional measurement;
determining a coordinate of a pattern having a dimension value which is equal to a stored dimension value, or the coordinate of the pattern having a dimension value within a predetermined range of dimension values including the stored dimension value;
controlling the charged particle beam irradiation tool and the stage to generate images of the plurality of patterns of the same shape exposed under a same exposure condition as the determined coordinate, or under a first exposure condition of a first area adjacent to a second area exposed by the first exposure condition as the determined coordinate;
extracting a contour by an image processing for each of the images, and synthesize the extracted contours to generate a synthesized contour; and
evaluating the patterns included in the images using the synthesized contour.
6. The non-transitory computer-readable medium according to claim 5 ,
wherein the program operating on the computer extracts a range of a second exposure condition for a pattern contained within a tolerance range of a shape evaluation parameter stored in advance.
7. The non-transitory computer-readable medium according to claim 6 ,
wherein the program operating on the computer selects the overlap range for a range of the first exposure condition, and the range of the second exposure condition.
8. The non-transitory computer-readable medium according to claim 5 ,
wherein the program operating on the computer selects a pattern whose dimensional measurement results satisfy specified conditions or exposure conditions by which the pattern is formed, based on dimensional measurements made for the plurality of patterns having different light exposure conditions.