1. A method for reducing the switching noise of an electromagnetic switching device including a coil drivable by a supply voltage, and an armature adapted to move moving switching contacts into contact with stationary switching contacts, the method comprising:
defining a first minimum value of the supply voltage, sufficient for at least moving the armature with the moving switching contacts;
using a drive unit to drive the coil, and hence the armature, with the moving switching contacts by the first minimum value of the supply voltage, at least until contact is made; and
increasing, as a function of time, the supply voltage from the first minimum value to a second minimum value, sufficient to move the switching contacts into sufficient mutual contact with the stationary switching contacts with pressure applied;
wherein the drive unit includes a switching element for driving a voltage limiter; and
wherein the switching element is an optocoupler.
2. A conveyor system adapted to perform the method of claim 1.
3. An elevator system, adapted to perform the method of claim 1.
4. An apparatus for reducing the switching noise of an electromagnetic switching device including a coil drivable by a supply voltage, and an armature adapted to move moving switching contacts into contact with stationary switching contacts, comprising:
a voltage control unit, adapted to fix the supply voltage, for moving the armature with the moving switching contacts, at least at a sufficient first minimum value; and
a drive unit, adapted to drive the coil with the first minimum value of the supply voltage at least until contact is made, wherein the supply voltage is then adapted to be increased via the voltage control unit, as a function of time, from the first minimum value to a second minimum value, sufficient to move the moving switching contacts into sufficient mutual contact
wherein the drive unit includes a switching element for driving a voltage limiter; and
wherein the switching element is an optocoupler. with the stationary switching contacts with pressure applied;
5. The apparatus as claimed in claim 4, wherein the drive unit includes a timer, adapted to determine a time for increasing the supply voltage from the first minimum value to the second minimum value.
6. The apparatus as claimed in claim 5, wherein the timer is an RC element.
7. The apparatus as claimed in claim 4, wherein the voltage control unit includes a switching element.
8. The apparatus as claimed in claim 4, wherein the drive unit includes the voltage limiter for limiting the supply voltage to the first minimum value, for allowing the supply voltage to rise to the second minimum value and for driving an actuating element, arranged in the voltage control unit.
9. The apparatus as claimed in claim 8, wherein the actuating element is a part of the voltage control unit for driving the coil.
10. The apparatus as claimed in claim 8, wherein the drive unit includes a reset element for resetting a timer when the supply voltage is switched off.
11. The apparatus as claimed in claim 4, wherein the voltage limiter is a part of the voltage control unit.
12. The apparatus as claimed in claim 4, wherein the drive unit includes a reset element for resetting a timer when the supply voltage is switched off.
13. The apparatus as claimed in claim 4, wherein the switching relationship between the drive unit and the voltage control unit is formed via a switching element.
14. A conveyor system including the apparatus of claim 4.
15. An elevator system including the apparatus of claim 4.
16. An apparatus for reducing the switching noise of an electromagnetic switching device including a coil drivable by a supply voltage, and an armature adapted to move moving switching contacts into contact with stationary switching contacts, comprising:
voltage control means for fixing the supply voltage to at least at a sufficient first minimum value, sufficient to move the armature with the moving switching contacts; and
driving means for driving the coil with the first minimum value of the supply voltage at least until contact is made, wherein the supply voltage is then increased, as a function of time, via the voltage control means from the first minimum value to a second minimum value, sufficient to move the moving switching contacts into sufficient mutual contact with the stationary switching contacts with pressure applied;
wherein the driving means includes a switching element for driving a voltage limiter; and
wherein the switching element is an optocoupler.
17. The apparatus as claimed in claim 16, wherein the driving means includes a timer, adapted to determine a time for increasing the supply voltage from the first minimum value to the second minimum value.
18. The apparatus as claimed in claim 16, wherein the voltage control means includes a switching element.
19. A conveyor system including the apparatus of claim 16.
20. An elevator system including the apparatus of claim 16.
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 electron beam exposure apparatus comprising:
a plurality of column cells arranged above a sample and configured to irradiate electron beams in parallel onto a surface of the sample;
an integrated controller configured to generate exposure data including an exposure position, an exposure pattern and an exposure time of each shot of the plurality of column cells;
a column cell control unit provided in each of the column cells and configured to control the column cell based on the exposure data;
a correction parameter storage unit provided in the integrated controller and configured to store a correction parameter for allowing a relationship between exposure intensity and a line width for a correction target column cell to coincide with a relationship between exposure intensity and a line width for a reference column cell selected from among the plurality of column cells;
a reference exposure time storage unit provided in the integrated controller and configured to store reference exposure time required to form a predetermined reference pattern having a line width as designed in the reference column cell; and
an exposure time calculating unit provided in the integrated controller and configured to obtain exposure time of the correction target column cell by correcting the reference exposure time based on the correction parameter.
2. The electron beam exposure apparatus according to claim 1, wherein
the correction parameter includes a first correction parameter for correcting a slope of the relationship between the exposure intensity and the line width for the correction target column cell, and a second correction parameter for correcting the intercept of the relationship between the exposure intensity and the line width for the correction target column cell.
3. The electron beam exposure apparatus according to claim 2, wherein
the exposure time calculating unit obtains the exposure time of the correction target column cell by adding the second correction parameter to a value obtained by multiplying the reference exposure time by the first correction parameter.
4. The electron beam exposure apparatus according to any one of claims 1 to 3, wherein
the reference pattern is a pattern in which a distance between edges opposite to each other is larger than a range of blurs caused by scattering the corresponding electron beam.
5. The electron beam exposure apparatus according to claim 4, wherein
the exposure time calculating unit obtains exposure time required to expose an exposure target pattern in the reference column cell by multiplying a proximity effect correction coefficient by the reference exposure time, the proximity effect correction coefficient representing the ratio between exposure intensity required to obtain a line width as designed in the exposure target pattern and exposure intensity required to obtain a line width as designed in the reference pattern.
6. The electron beam exposure apparatus according to claim 5, wherein
the first and second correction parameters are expressed by functions of the proximity effect correction coefficient, and values of the first and second correction parameters are determined based on the proximity effect correction coefficient of the exposure target pattern.
7. The electron beam exposure apparatus according to claim 1, wherein
the correction parameter storage unit stores an auxiliary exposure intensity correction parameter for allowing a relationship between auxiliary exposure intensity and the line width for the correction target column cell to coincide with a relationship between auxiliary exposure intensity and the line width for the reference column cell, and
the exposure time calculating unit obtains auxiliary exposure time of the correction target column cell by correcting auxiliary exposure time of the reference column cell based on the auxiliary exposure intensity correction parameter.
8. An electron beam exposure method for exposing a plurality of patterns in parallel on a wafer by use of a plurality of column cells configured to irradiate electron beams, the method comprising the steps of:
obtaining a relationship between exposure intensity and a line width for each of the column cells by exposing a predetermined pattern in the column cell while changing exposure time, and measuring the line width of the pattern;
obtaining a correction parameter for allowing a relationship between exposure intensity and a line width for a correction target column cell to coincide with a relationship between a line width and exposure intensity for a reference column cell selected from among the plurality of column cells;
obtaining reference exposure time required to form a predetermined reference pattern having a line width as designed in the reference column cell;
calculating exposure time of the correction target column cell based on the correction parameter and the reference exposure time; and
performing exposure in the correction target column cell based on the exposure time of the correction target column cell.
9. The electron beam exposure method according to claim 8, wherein
the correction parameter includes a first correction parameter for correcting a slope of the relationship between the exposure intensity and the line width for the correction target column cell, and a second correction parameter for correcting the intercept of the relationship between the exposure intensity and the line width for the correction target column cell.
10. The electron beam exposure method according to claim 9, wherein
the exposure time of the correction target column cell is obtained by adding the second correction parameter to a value obtained by multiplying the reference exposure time by the first correction parameter.
11. The electron beam exposure method according to any one of claims 8 to 10, wherein
the reference pattern is a pattern in which a distance between edges opposite to each other is larger than a range of blurs caused by scattering of the corresponding electron beam.
12. The electron beam exposure method according to claim 11, wherein
exposure time required to expose an exposure target pattern in the reference column cell is obtained by multiplying a proximity effect correction coefficient by the reference exposure time, the proximity effect correction coefficient representing the ratio between exposure intensity required to obtain a line width as designed in the exposure target pattern and exposure intensity required to obtain a line width as designed in the reference pattern.
13. The electron beam exposure method according to claim 12, further comprising the steps of:
obtaining the first and second correction parameters for each of an isolated pattern and a dense pattern, and obtaining dependency of the first and second correction parameters on the proximity effect correction coefficient by linear interpolation; and
determining values of the first and second correction parameters based on a proximity effect correction coefficient of the exposure target pattern.
14. An electron beam exposure method for exposing a plurality of patterns in parallel on a wafer by use of a plurality of column cells configured to irradiate electron beams, and then performing auxiliary exposure to correct the influence of a proximity effect during the exposure, the method comprising the steps of:
obtaining a relationship between auxiliary exposure intensity and a line width for each of the column cells by performing auxiliary exposure on a pattern exposed in the column cell while changing auxiliary exposure time, and measuring a line width of the pattern;
obtaining a correction parameter for allowing a relationship between auxiliary exposure intensity and a line width for a correction target column cell to coincide with a relationship between auxiliary exposure intensity and a line width for a reference column cell selected from among the plurality of column cells;
calculating auxiliary exposure time of the correction target column cell by correcting auxiliary exposure time of the reference column cell based on the correction parameter; and
performing auxiliary exposure in the correction target column cell based on the auxiliary exposure time of the correction target column cell.