Source: https://patents.google.com/patent/US20030024899A1/en
Timestamp: 2018-03-23 19:19:05
Document Index: 284262933

Matched Legal Cases: ['art 2', 'art 50', 'art 92', 'arts 93', 'art 92', 'art 93', 'art 94']

US20030024899A1 - Exposure method utilizing optical proximity corrected exposure patterns, an apparatus for generating optical proximity corrected exposure data, and an exposure apparatus for optical proximity corrected exposure data - Google Patents
Exposure method utilizing optical proximity corrected exposure patterns, an apparatus for generating optical proximity corrected exposure data, and an exposure apparatus for optical proximity corrected exposure data Download PDF
US20030024899A1
US20030024899A1 US10073246 US7324602A US2003024899A1 US 20030024899 A1 US20030024899 A1 US 20030024899A1 US 10073246 US10073246 US 10073246 US 7324602 A US7324602 A US 7324602A US 2003024899 A1 US2003024899 A1 US 2003024899A1
US10073246
US6968531B2 (en )
Yoshimasa Iiduka
In the exposure method which carries out optical proximity correction processing for exposure data having a plurality of exposure patterns and exposes a sample in accordance with such corrected exposure data, the exposure patterns to be corrected are converted, in the optical proximity correction processing, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, to form corrected exposure data. And, the minus pattern is deleted from the minus objective pattern of the corrected exposure data to bitmap a corrected exposure pattern, to expose a sample in accordance with such bitmapped corrected exposure pattern.
[0005]FIG. 1 is a diagram showing one example of the optical proximity effect. FIG. 1 shows how two kinds of pattern 1, 2 change by the optical proximity effect in the exposure pattern (1), the pattern on the reticle (2), and the pattern on the wafer (3). The square pattern 1 is a rectangular profile whose four corners are made at 90° in the exposure pattern, but when the reticle is exposed with laser beams, electron beams, or the like by utilizing the exposure pattern and developed, the pattern on the reticle leads to a profile whose four corners are slightly rounded like a pattern 1A. Furthermore, when the wafer is exposed by utilizing the reticle pattern and developed, the pattern to be formed on the wafer leads to a profile whose four corners are rounded like a pattern 1B, as shown in FIG. 1, and the square becomes approximately a round shape. This occurs by a cause that the frontward dispersion and rearward dispersion from peripheries are scarcely affected at the corners, and this cause is equal to a cause that leads to a phenomenon that a top end of a line pattern becomes a round profile, and further is thinned.
[0007]FIG. 2 is a diagram for explaining the optical proximity correction (OPC). Taking into consideration the optical proximity effect of FIG. 1, a serif pattern 1C is added to the four corners of the square exposure pattern 1, and the reticle pattern 1A and the pattern 1B on the wafer are formed by exposing and developing according to the OPC corrected exposure pattern. The reticle pattern 1A is deformed to a profile that the corners are rounded by the optical proximity effect, and the corner of the wafer pattern 1B becomes a sharp right-angled profile. Furthermore, in the linear exposure pattern 2, a recess part 2C is added to the positions confronting the patterns 3, 4, and the exposure and development are made by the OPC corrected exposure pattern. As a result, a slightly recessed profile 2D is obtained in the reticle pattern 2A and a flat line profile is obtained in the wafer pattern 2B.
It is therefore the object of the present invention to provide an exposure method which restricts an increase in the number of the optical proximity corrected exposure patterns, an exposure data processing apparatus, and an exposure apparatus.
[0015]FIG. 1 is a diagram showing one example of an optical proximity effect;
[0016]FIG. 2 is a diagram for explaining an optical proximity correction (OPC);
[0017]FIG. 3 is a flowchart in a general exposure data processing apparatus and exposure apparatus;
[0018]FIG. 4 is a diagram for explaining a first OPC processing;
[0019]FIG. 5 is a flowchart in an exposure data processing apparatus and exposure apparatus in the case where a second OPC processing is carried on;
[0020]FIG. 6 is a diagram for explaining a second OPC processing;
[0021]FIG. 7 is a flowchart of the OPC processing in this embodiment;
[0022]FIG. 8 is a diagram showing a serif correction;
[0023]FIG. 9 is a diagram showing a line correction;
[0024]FIG. 10 is a diagram showing a schematic configuration of the exposure apparatus;
[0025]FIG. 11 is a configuration diagram of a bitmap processing unit; and
[0026]FIG. 12 is a logic table of the bitmap processing unit.
Hereinafter, the embodiments of the present invention will be described with reference to the drawings. It is however to be understood that the scope of protection of the present invention is not limited to the following embodiments, but covers the invention defined in the claims and its equivalent.
[0028]FIG. 3 is a flowchart in a general exposure data processing apparatus and exposure apparatus. In the exposure data processing apparatus, design data DB1 are subjected to a data conversion processing in accordance with data conversion information DB2 (S1), and as the result, exposure data DB3 having the plurality of exposure patterns each designating an exposure region is generated. The data conversion information DB2 are parameters containing a power, a shift amount, and the like which correspond to a reticle to be exposed and developed. For example, in the case of rectangular patterns, the generated exposure data DB3 have an origin coordinate, a width and a height, and attribute data such as a profile code, etc. The exposure pattern comprises a quadrilateral rectangular pattern, a triangular pattern, a trapezoid pattern, and the like, and these profile codes are given as the attribute data. In the case of the triangular pattern, the exposure data have the origin coordinate, a length of a bottom side and a height, and the like, and in the case of the trapezoid pattern, the exposure data have the origin coordinate, lengths of an upper bottom and a lower bottom and a height, and the like.
[0032]FIG. 4 is a diagram for explaining a first OPC processing. In the same manner as FIGS. 1 and 2, FIG. 4A shows the OPC processing with respect to the corner rounding of the exposure pattern, and FIG. 4B shows the OPC processing with respect to a thinning of the linear exposure pattern. In the OPC processing with respect to the corner rounding of the exposure pattern, a serif correction pattern 10C is added to corners of the exposure pattern to be corrected 10. And, the exposure pattern to be corrected 10 and the serif correction pattern 10C are combined to form a corrected exposure pattern 10D, which is divided into a plurality of rectangular patterns. In this example, the corrected exposure pattern is divided into seven rectangular patterns d1 to d7. Namely, the exposure pattern to be corrected 10 is converted into the corrected exposure data DB5 consisting of the seven rectangular patterns d1 to d7. As the result, such the corrected exposure data are rendered to bitmap, and a sample such as a reticle, or the like is exposed to beams in accordance with the bitmap data, and is developed, so that a correction exposure pattern 10E is formed on the reticle.
[0036]FIG. 5 is a flowchart in the exposure data processing apparatus and the exposure apparatus in the case where a second OPC processing is carried out. Furthermore, FIG. 6 is a diagram for explaining the second OPC processing. As shown in FIG. 5, in the exposure data processing apparatus, the design data DB1 are subjected to a data conversion processing according to the data conversion information DB2 (S1), to form the exposure data DB3. This exposure data conversion processing is same as in the case of FIG. 3. Next, in the OPC processing S2, the exposure pattern to be corrected within the exposure data is converted into a minus objective pattern DB5A and a minus pattern DB5B in accordance with the OPC model table DB4, to form the corrected exposure data DB5. The exposure pattern to be corrected is converted into the minus objective pattern DB5A and the minus pattern DB5B, thereby restricting the increase in the number of patterns.
[0042]FIG. 7 is a flowchart of the OPC processing in this embodiment. In this embodiment, in the case of the OPC processing, the exposure pattern to be corrected is converted into any one of the first corrected exposure data having the plurality of exposure patterns obtained by dividing the corrected exposure pattern by the first OPC processing and the second corrected exposure data having the minus objective pattern and the minus pattern by the second OPC processing. In selecting either one, the data with the smaller number of patterns of the corrected exposure data are selected.
[0044]FIG. 8 is a diagram showing a serif correction. As shown in FIG. 4A, when the rectangular is subjected to a serif correction by the first OPC, the number of pattern reaches seven times, and on the other hand, as shown in FIG. 6A, when the rectangular is subjected to a serif correction by the second OPC, the number of pattern is limited to five times. Accordingly, it is understood that, in the serif correction with respect to the rectangular pattern, the second OPC processing is more advantageous.
[0046]FIG. 8B shows a comparable example with respect to the a triangular exposure pattern 40, and when the exposure pattern 40 is subjected to the first OPC processing OPC1, the number of pattern reaches five times, and on the other hand, when the exposure pattern 40 is subjected to the second OPC processing OPC2, the number of pattern is limited to four times. Accordingly, in the case of the triangular exposure pattern also, the second OPC processing is more advantageous. Incidentally, the reason that a horizontal division is made in the first OPC processing is that beams are swept in a horizontal direction in the beam exposure.
[0048]FIG. 9 is a diagram for explaining such the line correction. FIG. 9A shows the OPC of an exposure pattern to be corrected 50 having proximal exposure patterns 51, 52. In this case, in order to prevent that the exposure pattern to be corrected 50 are enlarged after being exposed and developed in an opposite side 53 confronting the proximal exposure patterns 51, 52, a recess part 50M is provided in an OPC exposure pattern 50E. In this case, when they are subjected to the first OPC processing, five division patterns are obtained, but when they are subjected to the second OPC processing, total three patterns of the single existent pattern 50 and the two minus patterns 50M are obtained. Accordingly, the second OPC processing is more advantageous.
[0049]FIG. 9B shows the OPC of an exposure pattern to be corrected 60 having a proximal exposure pattern 61. In this case, in the first OPC processing, the three division patterns are obtained, but in the second OPC processing, the total two patterns of a single existent pattern and a single minus pattern 60M are obtained. Accordingly, the second OPC processing is more advantageous.
[0050]FIG. 9C shows the OPC in the case where a proximal exposure pattern 71 is included in a top end part of a line pattern 70. In this case, in both the first and second OPC processings, a correction exposure pattern 70E has two patterns.
[0055]FIG. 10 is a diagram showing a schematic configuration of the exposure apparatus. This example is a laser beam exposure apparatus. Laser beams generated by a laser beam source 80 pass through a reflection mirror 81, an on/off switch 82 and a reflection mirror 83, and are irradiated to a scan mirror 84. The scan mirror 84 is a polygon mirror and scans the laser beams in a horizontal direction by rotating it. The laser beams pass through an object glass 85 and are irradiated to a reticle 87 mounted on a stage 86.
[0058]FIG. 11 is a configuration diagram of the bitmap processing unit. This bitmap processing unit comprises a figure code judgment part 92 for judging a figure code of pattern data included in the corrected exposure data DB5; dot signal conversion parts 93, 94 for converting the pattern into a dot signal; and NOR gates 95, 96. The figure code judgment part 92 judges the normal figure code and the minus figure code which are provided by the format conversion processing of FIG. 7, and the normal pattern provided with the normal figure code is supplied to a dot signal conversion part 93, and the minus pattern provided with the minus figure code is supplied to a dot signal conversion part 94. And, when the respective dot signals A, B pass through the two NOR gates 95, 96, the dot signal deleting the minus pattern from the normal pattern is generated.
[0059]FIG. 12 is a diagram showing a logic value table of the two NOR gates. When the dot signal B of the minus pattern is “1” at the time of the dot signal A of the normal pattern being “1,” the dot signal DOT becomes “0” (off) by a deletion. Furthermore, when the dot signal B of the minus pattern is “0” at the time of the dot signal A of the normal pattern being “1,” the dot signal DOT becomes “1” (on) without the deletion. And, at the time of the dot signal A of the normal pattern being “0,” the dot signal DOT becomes “0” (off). The on/off switch 82 within the exposure apparatus on/off-controls the laser beams according to this dot signal DOT.
1. An exposure method which processes an optical proximity correction to an exposure data having a plurality of exposure patterns and exposes a substrate in accordance with the corrected exposure data, the method comprising:
a correction processing step of converting an exposure pattern to be corrected, which is subject to an optical proximity effect, of the plurality of exposure patterns, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, to generate the corrected exposure data;
a bitmap processing step of deleting the minus pattern from the minus objective pattern of the corrected exposure data, to bitmap the corrected exposure pattern; and
an exposure step of exposing the substrate in accordance with the bitmapped corrected exposure pattern.
2. The exposure method according to claim 1, wherein
in the case of the optical proximity correction for preventing corners of the exposure pattern from being rounded, the exposure pattern to be corrected is converted, in the correction processing step, into the minus objective pattern which is an enlarged one of the exposure pattern to be corrected and into the minus pattern positioned at center on sides of the minus objective pattern.
3. The exposure method according to claim 1, wherein
in the case of the optical proximity correction for preventing an enlargement at position confronting adjacent other pattern in a linear exposure pattern, the exposure pattern to be corrected is converted, in the correction processing step, into the minus objective pattern consisting of the exposure patterns to be corrected and the minus pattern at the position confronting the adjacent other pattern.
in the correction processing step, if the number of patterns after conversion is smaller in a second optical proximity correction processing for converting the exposure pattern to be corrected into the minus objective pattern and the minus pattern, than in a first optical proximity correction processing for converting the exposure pattern to be corrected into a plurality of division exposure patterns obtained by dividing the corrected exposure patterns after the optical proximity correction, then the second optical proximity correction processing is carried out, and wherein if the number of patterns after conversion is greater in the second optical proximity correction processing than in the first optical proximity correction processing, then the first optical proximity correction processing is carried out.
5. An exposure system which processes an optical proximity correction to an exposure data having a plurality of exposure patterns and exposes a substrate in accordance with the corrected exposure data, the system comprising:
a correction processing unit which converts an exposure pattern to be corrected which is subject to an optical proximity effect, of the plurality of exposure patterns, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, to thereby the generate corrected exposure data;
a bitmap processing unit which deletes the minus pattern from the minus objective pattern of the corrected exposure data to bitmap the corrected exposure pattern; and
an exposure unit for exposing the substrate in accordance with the bitmapped correction exposure pattern.
6. The exposure system according to claim 5, wherein
in the case of the optical proximity correction for preventing corners of the exposure pattern from being rounded, the correction processing unit converts the pattern to be corrected, into the minus objective pattern which is an enlarged one of the exposure pattern to be corrected and into the minus pattern positioned at center on sides of the minus objective pattern.
7. The exposure system according to claim 5, wherein
in the case of the optical proximity correction for preventing an enlargement at position confronting adjacent other pattern in a linear exposure pattern, the correction processing unit converts the exposure pattern to be corrected, into the minus objective pattern consisting of the exposure pattern to be corrected and into the minus pattern at position confronting the adjacent other pattern.
8. The exposure system according to claim 5, wherein
the correction processing unit, if the number of patterns after conversion is smaller in the second optical proximity correction processing for converting the exposure pattern to be corrected into the minus objective pattern and the minus pattern, than in the first optical proximity correction processing for correcting the exposure pattern to be corrected into the plurality of division exposure patterns obtained by dividing the correction exposure patterns after the optical proximity correction, carries out the second optical proximity correction processing; and the correction processing unit, if the number of patterns after conversion is greater in the second optical proximity correction processing than in the first optical proximity correction processing, carrying out the first optical proximity correction processing.
9. An exposure data processing apparatus which processes an optical proximity correction to an exposure data having a plurality of exposure patterns, to generate a corrected exposure data, comprising:
a correction processing unit for converting an exposure pattern to be corrected, which is subject to an optical proximity effect, of the plurality of exposure patterns, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, to generate the corrected exposure data.
10. The exposure data processing apparatus according to claim 9, wherein
in the case of the optical proximity correction for preventing corners of the exposure pattern from being rounded, the correction processing unit converts the pattern to be corrected into the minus objective pattern which is an enlarged one of the exposure pattern to be corrected and into the minus pattern positioned at center on sides of the minus objective pattern.
11. The exposure data processing apparatus according to claim 9, wherein
in the case of the optical proximity correction for preventing an enlargement at position confronting adjacent other pattern in a linear exposure pattern, the correction processing unit converts the exposure pattern to be corrected into the minus objective pattern consisting of the exposure pattern to be corrected and into the minus pattern at position confronting the adjacent other pattern.
12. The exposure data processing apparatus according to claim 9, wherein
the correction processing unit, if the number of patterns after conversion is smaller in a second optical proximity correction processing for converting the exposure pattern to be corrected into the minus objective pattern and the minus pattern, than in a first optical proximity correction processing for converting the exposure pattern to be corrected into a plurality of division exposure patterns obtained by dividing the correction exposure patterns after the optical proximity correction, carries out the second optical proximity correction processing; and the correction processing unit, if the number of patterns after conversion is greater in the second optical proximity correction processing than in the first optical proximity correction processing, carries out the first optical proximity correction processing.
13. An exposure apparatus for exposing a substrate to exposure patterns, in accordance with exposure data, comprising:
a bitmap processing unit which inputs a corrected exposure data obtained by converting an exposure pattern to be corrected which is subject to an optical proximity effect, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, and deletes the minus pattern from the minus objective pattern to bitmap a corrected exposure pattern; and
an exposure unit for exposing the substrate in accordance with the bitmapped corrected exposure pattern.
US10073246 2001-08-02 2002-02-13 Exposure method utilizing optical proximity corrected exposure patterns, an apparatus for generating optical proximity corrected exposure data, and an exposure apparatus for optical proximity corrected exposure data Expired - Fee Related US6968531B2 (en)
JP2001-234704 2001-08-02
JP2001234704A JP4615156B2 (en) 2001-08-02 2001-08-02 Exposure method utilizing optical proximity corrected exposure pattern, optical proximity corrected apparatus for generating exposure data, and optical proximity corrected exposure data of the exposure apparatus
US20030024899A1 true true US20030024899A1 (en) 2003-02-06
US6968531B2 US6968531B2 (en) 2005-11-22
ID=19066264
US10073246 Expired - Fee Related US6968531B2 (en) 2001-08-02 2002-02-13 Exposure method utilizing optical proximity corrected exposure patterns, an apparatus for generating optical proximity corrected exposure data, and an exposure apparatus for optical proximity corrected exposure data
US (1) US6968531B2 (en)
JP (1) JP4615156B2 (en)
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JP2000235251A (en) * 1999-02-16 2000-08-29 Sony Corp Exposure pattern correction method, exposure method, aligner, photomask and semiconductor device
US20160209738A1 (en) * 2012-03-28 2016-07-21 Intel Corporation Projection of a plurality of structured light patterns
US9823560B2 (en) * 2012-03-28 2017-11-21 Intel Corporation Projection of a plurality of structured light patterns
US6968531B2 (en) 2005-11-22 grant
JP2003043664A (en) 2003-02-13 application
JP4615156B2 (en) 2011-01-19 grant
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:IIDUKA, YOSHIMASA;KOBAYASHI, RYUJI;ITO, TAKAHISA;REEL/FRAME:012586/0635