1. A system for measuring a pattern on a sample, comprising:
a data processing system that processes a set of two-dimensional distribution data of intensities from the sample, to calculate;
a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation coefficient between a first portion of the edge fluctuation data and a second portion of the edge fluctuation data.
2. The system according to claim 1 wherein:
said pattern is a line pattern defined by a set of at least two edge points; and
the data processing system calculates the correlation coefficient between the first portion of the edge fluctuation data for one side of the line pattern and the second portion of the edge fluctuation data for an opposite side of the line pattern.
3. The system according to claim 2, comprising:
a memory device that stores a table of candidate coefficient data of the correlation coefficient, and a corresponding cause of occurrence of the edge fluctuation in the line pattern for each candidate coefficient data.
4. The system according to claim 1 wherein:
the data processing system calculates a spatial frequency distribution of the edge fluctuation data.
5. A system for measuring a pattern on a sample, comprising:
a data processing system that processes a set of two-dimensional distribution data of intensities of secondary electrons or reflected electrons from said sample, to calculate;
a set of edge points indicative of positions of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation between first potion of said edge fluctuation data and second portion of said edge fluctuation data;
wherein the data processing system obtains the degree of an edge fluctuation by calculating a standard deviation of the edge fluctuation data.
6. The system according to claim 1, wherein:
the data processing system calculates a square root of an average of root-mean-square values of differences, each between a set of edge points derived with respect to a plurality of thresholds and the approximation edge.
7. A method for measuring a pattern on a sample, comprising:
processing a set of two-dimensional distribution data of intensities from the sample, to calculate:
a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation coefficient between a first portion of the edge fluctuation data and a second portion of the edge fluctuation data.
8. The method according to claim 7, wherein:
said pattern is a line pattern defined by a set of at least two edge points; and
the processing includes calculating the correlation coefficient between the first portion of the edge fluctuation data for one side of the line pattern and the second portion of the edge fluctuation data for an opposite side of the line pattern.
9. A method for measuring a pattern on a sample, comprising:
processing a set of two-dimensional distribution data of intensities from the sample, to calculate:
a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an a approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation coefficient between a first portion of the edge fluctuation data and a second portion of the edge fluctuation data
storing, within a memory device, a table of candidate coefficient data of the correlation coefficient, and a corresponding cause of occurrence of the edge fluctuation in the line pattern for each candidate coefficient data.
10. The method according to claim 7, wherein:
the processing calculates a spatial frequency distribution of the edge fluctuation data.
11. A method for measuring a pattern on a sample, comprising;
processing a set of two-dimensional distribution data of intensities from the sample, to calculate:
a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation between a first portion of the edge fluctuation data and a second portion of the edge fluctuation data;
wherein the processing obtains the degree of an edge fluctuation by calculating a standard deviation of the edge fluctuation data.
12. The method according to claim 7, wherein:
the processing calculates a square root of an average of root-mean-square values of differences each between a set of edge points derived with respect to a plurality of thresholds and the approximation edge.
13. A computer-readable medium having a sequence of computer implementable program code thereon, which when implemented, causes the computer to perform:
processing a set of two-dimensional distribution data of intensities from the sample, to calculate:
a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data;
an approximation edge indicative of the edge of the pattern;
an edge fluctuation data by calculating a difference between the set of edge points and said approximation edge; and
a correlation coefficient between a first portion of the edge fluctuation data and a second portion of the edge fluctuation data.
14. The computer-readable medium according to claim 13, wherein:
said pattern is a line pattern defined by a set of at least two edge points; and
the processing includes calculating the correlation coefficient between the first portion of the edge fluctuation data for one side of the line pattern and the second portion of the edge fluctuation data for an opposite side of the line pattern.
15. The computer-readable medium according to claim 14, wherein the sequence of computer implementable program code, when implemented, causes the computer to:
access a table having stored therein, candidate coefficient data of the correlation coefficient, and a corresponding cause of occurrence of the edge fluctuation in the line, pattern for each candidate coefficient data.
16. The computer-readable medium according to claim 13, wherein:
the processing calculates a spatial frequency distribution of the edge fluctuation data.
17. The computer-readable medium according to claim 13, wherein:
the processing obtains the degree of the edge fluctuation by calculating a standard deviation.
18. The computer-readable medium according to claim 13, wherein:
the processing calculates a square root of an average of root-mean-square values of differences each between a set of edge points derived with respect to a plurality of thresholds and the approximation edge.
19. A system for measuring a pattern on a sample, according to claim 1, comprising:
a scanning electron microscope for obtaining said set of two-dimensional distribution data of intensities.
20. A system for measuring a pattern on a sample, according to claim 5, comprising:
a scanning electron microscope for obtaining said set of two-dimensional distribution data of intensities.
21. A system for measuring a pattern on a sample, according to claim 1, wherein the correlation coefficient is a statistically-calculated correlation coefficient.
22. A system for measuring a pattern on a sample, according to claim 5, wherein the correlation coefficient is a statistically-calculated correlation coefficient.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An optical module, comprising:
a fiber optic transceiver (FOT) having a light emitting element andor a light receiving element;
a shield case covering and shielding the FOT;
a pressing portion formed in the shield case and directly or indirectly contributing to positioning the FOT, and
a stress countermeasure portion formed between the pressing portion and a substrate connection portion of the shield case and distributing, absorbing, or mitigating a stress due to deformation and displacement of the pressing portion.
2. The optical module according to claim 1, wherein a formation range of the stress countermeasure portion is set to a range equal to or more than a width of the pressing portion and a range more than a width of the substrate connection portion.
3. The optical module according to claim 1 or 2, wherein the stress countermeasure portion is arranged and formed around the pressing portion.