Source: http://www.google.com/patents/US7371997?ie=ISO-8859-1
Timestamp: 2014-07-22 11:31:04
Document Index: 24167060

Matched Legal Cases: ['art 11', 'art 11', 'art 11', 'art 12', 'art 12', 'art 12', 'arts 62', 'arts 63', 'arts 63', 'arts 62', 'art 11', 'art 62', 'art 10', 'art 62', 'art 10', 'art 311', 'art 1012', 'art 1035', 'art 1011', 'art 1035', 'art 1011', 'art 1035', 'art 2011', 'art 2011', 'art 2012', 'art 2006', 'art 2006']

Patent US7371997 - Thermal processing apparatus and thermal processing method - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign in<nobr>Advanced Patent Search</nobr>PatentsIn a thermal processing apparatus, using a lamp for heating a substrate, an opening is formed for a camera unit, which is used to image portions of an auxiliary ring supporting the substrate, to obtain the position of the center of the auxiliary ring. The camera further images the substrate to determine...http://www.google.com/patents/US7371997?utm_source=gb-gplus-sharePatent US7371997 - Thermal processing apparatus and thermal processing methodAdvanced Patent SearchPublication numberUS7371997 B2Publication typeGrantApplication numberUS 11/064,755Publication dateMay 13, 2008Filing dateFeb 1, 2005Priority dateMar 25, 2002Fee statusPaidAlso published asUS6868302, US20030186563, US20050149222Publication number064755, 11064755, US 7371997 B2, US 7371997B2, US-B2-7371997, US7371997 B2, US7371997B2InventorsToshiyuki Kobayashi, Yoshiro Koyama, Mitsukazu TakahashiOriginal AssigneeDainippon Screen Mfg. Co., Ltd.Export CitationBiBTeX, EndNote, RefManPatent Citations (6), Non-Patent Citations (2), Referenced by (3), Classifications (20), Legal Events (1) External Links: USPTO, USPTO Assignment, EspacenetThermal processing apparatus and thermal processing methodUS 7371997 B2Abstract In a thermal processing apparatus, using a lamp for heating a substrate, an opening is formed for a camera unit, which is used to image portions of an auxiliary ring supporting the substrate, to obtain the position of the center of the auxiliary ring. The camera further images the substrate to determine the center of the substrate before the thermal processing apparatus receives and places the substrate on the auxiliary ring. The thermal processing apparatus moves the substrate so that the center thereof coincides with the center of the auxiliary ring, and thereafter places the former on the latter. Thus, the auxiliary ring can be designed to reduce overlaps of the auxiliary ring and the outer edge of the substrate while overlaps can be uniform over the entire circumference of the substrate to improve temperature uniformity of the substrate.
an image pickup system capturing images of a plurality of portions of said ring, further comprising a rotation mechanism rotating said ring while directing said ring toward a prescribed direction.
an image pickup system capturing images of a plurality of portions of said ring, wherein
said image pickup system includes a plurality of image pickup parts set on different positions.
said image pickup system includes at least three said image pickup parts set on different positions.
4. A thermal processing apparatus capable of heating a substrate with light, comprising:
an image pickup system capturing images of a plurality of portions of said ring, further comprising a chamber storing said lamp, said ring and said substrate, wherein
said chamber is formed with an opening so that said image pickup system captures said images of said ring from outside said chamber through said opening.
said opening is formed on a position closer to said lamp than said substrate.
6. The thermal processing apparatus according to claim 4, further comprising a light source part emitting illumination light for illuminating said ring through said opening.
7. A thermal processing apparatus capable of heating a substrate with light, comprising:
an image pickup system comprising a plurality of image pickup parts capturing images of said outer edge of said substrate, wherein
said image pickup system comprises at least three said image pickup parts.
8. A thermal processing apparatus capable of heating a substrate with light, comprising:
said image pickup system also captures an image of said ring.
the respective ones of said plurality of image pickup parts simultaneously capture respective said images of said outer edge of said substrate and said ring.
10. A thermal processing apparatus capable of heating a substrate with light, comprising:
an image pickup system comprising a plurality of image pickup parts capturing images of said outer edge of said substrate, further comprising a chamber storing said lamp, said ring and said substrate, wherein
an opening is formed in said chamber so that said image pickup system captures said images of said outer edge of said substrate from outside said chamber through said opening.
12. The thermal processing apparatus according to claim 10, farther comprising a light source part emitting illumination light illuminating at least said outer edge of said substrate through said opening.
CROSS REFERENCE TO RELATED APPLICATION This is a division under 37 C.F.R. �1.53(b) of prior application Ser. No. 10/394,895, filed Mar. 21, 2003 now U.S. Pat. No. 6,868,302 by Toshiyuki KOBAYASHI, et al., entitled THERMAL PROCESSING APPARATUS AND THERMAL PROCESSING METHOD, the contents of which are incorporated herein by reference.
As the requirement for refinement of a device such as a semiconductor device is increased, a rapid thermal process (hereinafter abbreviated as �RTP�) has been going to play an important role as one of heating steps for a semiconductor substrate (hereinafter referred to as �substrate�). The RTP is performed mainly with a lamp employed as a heat source. Briefly stated, a processing chamber is kept in a prescribed gas atmosphere for heating a substrate to a prescribed temperature (e.g., 1100� C.) in several minutes (temperature increase step), maintaining the substrate at the temperature for a constant time (e.g., several 10 seconds) (holding step) and thereafter turning off the lamp thereby rapidly cooling the substrate.
Further, clearances (the so-called �slacks�) are provided on engaging portions between the auxiliary and screening rings and members supporting these rings respectively, for preventing the rings from cracking resulting from expansion in heating. When the thermal processing is repeated, therefore, the positions of the auxiliary ring and the screening ring change, i.e., the positions of the centers of the auxiliary ring and the screening ring deviate from the center of the substrate, due to difference between the temperatures or the thermal expansion coefficients of the rings and the members supporting the same. In consideration of this factor, the conventional thermal processing apparatus is so designed as to sufficiently increase the overlaps between these structures so that no clearance is defined between the substrate and the auxiliary ring or between the auxiliary ring and the screening ring to introduce the light from the lamp into the thermometer also when displacement is caused.
SUMMARY OF THE INVENTION The present invention is intended for a technique for reducing displacement between a substrate and an auxiliary ring thereby suppressing overlaps and rendering the overlaps constant for improving temperature uniformity of the substrate in heating.
The present invention is also directed to a thermal processing apparatus comprising a lamp irradiating a substrate with light and a ring having an annular support part coming into contact with the outer edge of the substrate for supporting the outer edge from below and outwardly spreading from the outer edge, while a numerical value obtained in terms of �mm2� of the product (area) of a support width of a portion where the outer edge of the substrate and the support part overlap with each other and the thickness of the support part is rendered not more than twice a numerical value obtained in terms of �mm� of the thickness (length) of the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates the relation between the temperature of a substrate and the time;
FIG. 36 illustrates the relation between thickness difference D and a product (T�W); and
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a longitudinal sectional view showing the structure of a thermal processing apparatus 1 according to a first preferred embodiment of the present invention. FIG. 3 omits parallel oblique lines with respect to sections of details.
A plurality of gas inlets 111 and a plurality of outlets 112 are formed on the side wall of the body part 11. The processing space 11 a performs gas replacement by (enforcedly) discharging gas from the outlets 112 while introducing gas (e.g., nitrogen, oxygen or the like) responsive to the type of processing performed on the substrate 9 through the gas inlets 111. The thermal processing apparatus 1 is provided with a shower plate 22 of quartz formed with a large number of holes between the substrate 9 and the chamber window 21, for homogeneously supplying the gas introduced from the gas inlets 111 to the upper surface of the substrate 9 through the shower plate 22. The gas employed for the processing is guided to the outlets 112 from below the processing space 11 a. A cylindrical member 33 centered at a central axis 1 a of the apparatus 1 supports the support ring group 30, while a coupling member 331 is mounted on the lower end of the cylindrical member 33. Another coupling member 332 opposed to the coupling member 331 is provided under the body part 11 so that the coupling members 331 and 332 form a magnetic coupling mechanism. The coupling member 332 rotates about the central axis 1 a through a motor 333. Thus, the coupling member 331 provided in the body part 11 rotates due to magnetic action, while the substrate 9 and the support ring group 30 rotate about the central axis 1 a while keeping the direction of the main surface constant.
As shown in FIG. 3, the lower surface of the lid part 12 of the thermal processing apparatus 1 defines a reflecting surface (hereinafter referred to as �reflector�) 121 opposed to the upper surface of the substrate 9, and a bar-shaped upper lamp group 41 is arranged along the reflector 121 so that respective lamps are along a direction X. The reflector 121 reflects a component of light upwardly emitted from the upper lamp group 41 and applies the same to the substrate 9. The upper lamp group 41 is formed by infrared halogen lamps, for example. A bar-shaped lower lamp group 42 is arranged under the upper lamp group 41, i.e., between the upper lamp group 41 and the substrate 9, so that respective lamps are along a direction Y perpendicularly to the upper lamp group 41.
A plurality of radiation thermometers 51 are mounted under the substrate 9 outwardly from the central axis 1 a, The radiation thermometers 51 receive infrared light from the substrate 9 through a window member 50 provided on the reflector 13 thereby measuring the temperature of the substrate 9. The plurality of radiation thermometers 51 measure the temperature of the substrate 9 placed on the support ring group 30 and rotated in response to distances from the central axis 1 a. At this time, the substrate 9, the support ring group 30 and the cylindrical member 33 inhibit infrared radiation from the lamp groups 41 and 42 from entering the radiation thermometers 51, so that the radiation thermometers 51 correctly measure the temperature.
The thermal processing apparatus 1 is further provided with three camera units 6 on the lid part 12. The camera units 6 capture images of the auxiliary ring 31 through openings 120 of 5 mm in diameter, for example, formed in the lid part 12. The camera units 6 comprise image pickup parts 62 and light source parts 63 mounted on optical units 61, so that half mirrors 611 provided in the optical units 61 reflect light from the light source parts 63 and guide the reflected light to the auxiliary ring 31 as illumination light through the openings 120. Light from the auxiliary ring 31 is transmitted through the half mirrors 611 and guided to the image pickup parts 62. The three camera units 6 are mounted on positions rotated by 120� from each other about the central axis 1 a, as shown by phantom lines in FIG. 4.
As shown in FIG. 3, a plurality of lift mechanisms 71 (FIG. 3 illustrates only a single lift mechanism 71 with two-dot chain lines) vertically moving lift pins 711 are mounted on the lower surface of the reflector 13 provided on the lower portion of the apparatus 1, while an openable/closeable gate 115 is provided on the side surface of the body part 11. When an external transport robot 8 (see FIG. 6) introduces or discharges the substrate 9 into or from the thermal processing apparatus 1 through the gate 115, the lift mechanisms 71 bring the lift pins 711 into contact with the lower surface of the substrate 9 for vertically moving the substrate 9, thereby transferring the substrate 9 between an arm 82 (see FIG. 9) of the transport robot 8 and the lift pins 711.
When placing the substrate 9 on the auxiliary ring 31, the thermal processing apparatus 1 closes the gate 115 shown in FIG. 3, supplies the processing space 11 a with an atmosphere of processing gas and rotates the substrate 9 with the auxiliary ring 31 for thermally processing the substrate 9 with the lamps (step S118). When completing the thermal processing, the thermal processing apparatus 1 replaces the gas in the processing space 11 a and opens the gate 115, so that the lift pins 711 push up the substrate 9. The transport robot 8 inserts the arm 82 into a portion under the substrate 9, so that the lift pins 711 move down to place the substrate 9 on the arm 82. The arm 82 discharges the substrate 9 from the thermal processing apparatus 1 (step S19).
FIG. 12 illustrates a thermal processing apparatus 1 according to a second preferred embodiment of the present invention in a similar manner to FIG. 10. The thermal processing apparatus 1 according to the second preferred embodiment is similar to that according to the first preferred embodiment except that two camera units 6 are provided at an angle of about 90� with respect to a central axis 1 a of the apparatus 1.
According to the third preferred embodiment, the thermal processing apparatus 1 inputs the image captured by the image pickup part 62 in an image processing circuit 65 (step S21), so that a total control part 10 thereafter controls a motor 333 similar to that shown in FIG. 3 and a rotation mechanism 330 formed by the motor 333 and coupling members 331 and 332 rotates the auxiliary ring 31 by 90�, for example (step S22). Then, the image pickup part 62 captures another image of the auxiliary ring 31 (step S23). Thus, it follows that the image processing circuit 65 receives images of two portions of the auxiliary ring 31.
While the centers of the substrate 9 and the auxiliary ring 31 do not coincide with each other in a strict sense when the thermal processing apparatus 1 moves the substrate 9 by the average vector 608 e, the center of the substrate 9 introduced into the thermal processing apparatus 1 is approximate to that of the auxiliary ring 31 and the three camera units 6 are uniformly arranged every 120� about a central axis 1 a as shown in FIG. 19, and hence the thermal processing apparatus 1 can sufficiently approach the center of the substrate 9 to that of the auxiliary ring 31 by moving the substrate 9 by the average vector 608 e. The total control part 10 may alternatively obtain the movement by another method of obtaining a vector toward the circumcenter of a triangle formed by the points of the three vectors 608 a, 608 b and 608 c, for example.
The thermal processing apparatus 1 according to the sixth preferred embodiment first positions the auxiliary ring 31 with the pin hoisting mechanisms 72 before receiving the substrate 9. FIG. 23 illustrates the positioned auxiliary ring 31. The auxiliary ring 31 is placed on a cushion ring 32 in a slightly movable state as described with reference to the first preferred embodiment, and the cushion ring 32 is placed on a cylindrical member 33 also in a slightly movable state (see FIG. 5). In the thermal processing apparatus 1, each pin hoisting mechanism 72 moves up the positioning pin 721 having a tapered forward end along arrow 721 a thereby bringing the positioning pin 721 into contact with the forward end of a support part 311 for the auxiliary ring 31 and horizontally sliding the auxiliary ring 31 along arrow 31 a. As shown in FIG. 22, the positioning pins 721 of the two pin hoisting mechanisms 72 urge the auxiliary ring 31 thereby moving the same in a direction Y in FIG. 22. Thus, it follows that the support ring group 30 moves to a constant position deviating to a direction (+Y) for locating the auxiliary ring 31 on a prescribed position.
When completely thermally processing the substrate 9, the thermal processing apparatus 1 stops rotating the auxiliary ring 31 at an angle of 180� with respect to that when receiving the substrate 9. Thus, it follows that the auxiliary ring 31 is located on a position deviating toward the direction (−Y) and the positioning pins 721 properly position the auxiliary ring 31 before the same receives a subsequent substrate 9 thereon.
The lower surface of the lid part 1012 of the thermal processing apparatus 1001 defines a reflecting surface (hereinafter referred to as �reflector�) 1121 opposed to the upper surface of the substrate 9, and a bar-shaped upper lamp group 1041 is arranged along the reflector 1121 so that respective lamps are along a direction X. The reflector 1121 reflects a component of light upwardly emitted from the upper lamp group 1041 and applies the same to the substrate 9. The upper lamp group 1041 is formed by infrared halogen lamps, for example. A bar-shaped lower lamp group 1042 is arranged under the upper lamp group 1041, i.e., between the upper lamp group 1041 and the substrate 9, so that respective lamps are along a direction Y perpendicularly to the upper lamp group 1041.
The second auxiliary ring 1032 is made of silicon carbide and the cylindrical member 1033 is made of quartz as hereinabove described while the thermal expansion coefficient of silicon carbide is larger than that of quartz by about one place, and hence the clearance, having a width L2 in FIG. 28, between the cylindrical surfaces 1322 a and 1331 a of the concave portion 1322 and the convex portion 1331 of the second auxiliary ring 1032 and the cylindrical member 1033 is increased when the thermal processing apparatus 1001 heats the substrate 9. Further, the support part 1035 is mounted on the body part 1011 cooled to less than 100� C., and hence the clearance, having a width L3 in FIG. 28, between the cylindrical surface 1342 a of the concave portion 1342 of the screening ring 1034 and the surface 1351 a of the support pin 1351 of the support part 1035 is increased when the thermal processing apparatus 1001 heats the screening ring 1034.
More specifically, the clearances between the concave portions 1312, 1322 and 1342 and the convex portions 1321 and 1331 and the support pin 1351 are set to 0.1 mm in the state shown in FIG. 27 when the diameter of the substrate 9 processed by thermal processing apparatus 1001 is 300 mm. The diameters of the auxiliary ring group 1030 and the screening ring 1034 are increased by about 1.5 mm when heated to 1100 to 1200� C., and hence the radial widths of the concave portions 1312, 1322 and 1342 are set larger than the widths of the convex portions 1321 and 1331 and the support pin 1351 by about 1 mm. In other words, slacks of about 1 mm are provided. Thus, the thermal processing apparatus 1001 can prevent cracking resulting from excess stress also when the first and second auxiliary rings 1031 and 1032 and the screening ring 1034 are expanded by heating.
The support pin 1351 supports the screening ring 1034, thereby preventing the clearance between the outer side of the screening ring 1034 and the body part 1011 from storing gas. The support pin 1351 may alternatively be replaced with an annular recessed member centered at the central axis 1 a. When completely processing the substrate 9, the thermal processing apparatus 1001 stops supplying power to the lamp groups 1041 and 1042 and reduces the temperature in the processing space 1010. Consequently, the first and second auxiliary rings 1031 and 1032 and the screening ring 1034 are contracted while the diameters of the cylindrical member 1033 and the arrangement of the support part 1035 are also slightly reduced, so that the widths L1 to L3 shown in FIG. 28, i.e., the clearances between the cylindrical surfaces 1321 a and 1312 a, between the cylindrical surfaces 1331 a and 1322 a and between the surface 1351 a and the cylindrical surface 1342 a are reduced and the arrangement of the respective structures returns to the state shown in FIG. 27.
As shown in FIGS. 31 and 32, a cylindrical member 2033 centered at a central axis 1 a supports the support ring group 2030, while a coupling member 2331 is mounted on the lower end of the cylindrical member 2033. Another coupling member 2332 opposed to the coupling member 2331 is provided under the body part 2011 so that the coupling members 2331 and 2332 form a magnetic coupling mechanism. The coupling member 2332 rotates about the central axis 1 a through a motor 2333 shown in FIG. 32. Thus, the coupling member 2331 provided in the body part 2011 rotates due to magnetic action, while the substrate 9 and the support ring group 2030 rotate about the central axis 1 a. The lower surface of the lid part 2012 defines a reflecting surface (hereinafter referred to as �reflector�) 2121 opposed to the upper surface of the substrate 9, and a bar-shaped upper lamp group 2041 is arranged along the reflector 2121 so that respective lamps are along a direction X in FIG. 31. The reflector 2121 reflects a component of light upwardly emitted from the upper lamp group 2041 and applies the same to the substrate 9.
Each of the upper and lower lamp groups 2041 and 2042 is divided into small groups in response to distances from the central axis 1 a. FIG. 32 shows lamps 2411, 2412, 2413 and 2414 of the upper lamp group 2041 grouped successively from the side of the central axis 1 a, and FIG. 31 shows lamps 2421, 2422, 2423 and 2424 of the lower lamp group 2042 grouped successively from the side of the central axis 1 a. FIG. 33 is a block diagram showing the connectional relation between the grouped lamps 2411, 2412, 2413, 2414, 2421, 2422, 2423 and 2424 and a lamp control part 2006 supplying power to the lamps 2411, 2412, 2413, 2414, 2421, 2422, 2423 and 2424 (each block shows a plurality of lamps). As shown in FIG. 33, the grouped lamps 2411, 2412, 2413 and 2414 of the upper lamp group 2041 and the grouped lamps 2421, 2422, 2423 and 2424 of the lower lamp group 2042 are individually connected to the lamp control part 2006, and supplied with power independently of each other. Thus, intensity distribution of light applied to the upper surface of the substrate 9 is controlled.
FIG. 36 illustrates the relation between thickness difference D (see FIG. 2) between the outer edge and the center of the substrate 9 and the product (T�W) of the support part thickness T and the support width W when forming an oxide film through an RTP in the thermal processing apparatus 2001 and varying the support part thickness T and the support width W shown in FIG. 35 as shown in FIG. 37.
In measurement, the substrate 9 having a diameter 200 mm and a substrate thickness Tw of 0.725 mm was rapidly heated to a target temperature of 1100� C. at about 100� C./s and thereafter held at the target temperature for 60 seconds. In order to obtain the thickness difference D, thicknesses were measured on a position (corresponding to that of the distance R2 in FIG. 2) of 2 mm inside the outer edge of the substrate 9 and a position (corresponding to that of the distance R1 in FIG. 2) of 10 mm inside the outer edge of the substrate 9 respectively. It has been confirmed that the thickness was substantially constant inside the position of 10 mm inside the outer edge of the substrate 9 and the average thickness was about 11 nm.
It is understood from FIG. 36 that proportionality is present between the thickness difference D and the product (T�W), as shown by a straight line Z. Assuming that allowable dispersion of the thickness is �1%, allowable thickness difference D is about 0.22 nm (2% of the average thickness of 11 nm). According to the straight line Z, therefore, it can be said possible to reduce dispersion of the thickness to not more than �1% if the product (T�W) is not more than about 1.5 mm2. Considering that dispersion of the thicknesses is influenced by the support part thickness T and the support width W as the substrate thickness Tw is reduced and that the substrate 9 having the substrate thickness Tw of 0.725 mm was used in measurement, it is estimated that dispersion of the thickness can be rendered within �1% of the average thickness when a numerical value (T1�W1) obtained in terms of �mm2,� of the product (T�W) is not more than about twice a numerical value (TW1) obtained in terms of �mm� of the substrate thickness TW. In other words, temperature uniformity of the substrate 9 can be improved by satisfying relation expressed as ((T1�W1)≦(Tw1�2)).
While it can be said preferable that the product (T�W) is not more than 1.5 mm2 when forming a film of an ordinary thickness of about 10 nm from FIG. 36, it is preferable that the support part thickness T and the support width W are rendered not more than 0.5 mm and not more than 3 mm respectively considering that this condition has been guided from the measurement range shown in FIG. 37. In consideration of a point that reliable measurement results are obtained, it can be said more preferable to render the product (T�W) and the support part thickness T not more than 1.2 mm2 and not more than 0.4 mm respectively.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS6163648Aug 9, 1999Dec 19, 2000Ushiodenki Kabushiki KaishaHeating device of the light irradiation type and holding device thereforUS6831258 *Jun 30, 2003Dec 14, 2004Kabushiki Kaisha ToshibaHeating device, method for evaluating heating device and pattern forming methodUS6885815 *Jul 16, 2003Apr 26, 2005Dainippon Screen Mfg. Co., Ltd.Thermal processing apparatus performing irradiating a substrate with lightUS7038173 *Feb 3, 2003May 2, 2006Dainippon Screen Mfg. Co., Ltd.Heat substrates; positioning lamps perpendicular with reflector; efficient radiation; ring of reflective light; uniform temperatureJP2000058471A Title not availableJP2000150405A Title not available* Cited by examinerNon-Patent CitationsReference1English translation of Abstract from Japanese Patent Application Laid-Open No. 2000-058471.2English translation of Abstract from Japanese Patent Application Laid-Open No. 2000-150405.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS8470128Feb 12, 2010Jun 25, 2013Canon Anelva CorporationTray, tray support member, and vacuum processing apparatusUS8741064 *Jun 26, 2012Jun 3, 2014Tokyo Electron LimitedHeat treatment method and heat treatment apparatusUS20120329291 *Jun 26, 2012Dec 27, 2012Tokyo Electron LimitedHeat treatment method and heat treatment apparatus* Cited by examinerClassifications U.S. Classification219/390, 118/724, 392/414, 219/411, 118/50.1, 392/418, 118/725, 219/405, 257/E21.324International ClassificationF27B5/14, H01L21/00, H01L21/68, A21B2/00, H01L21/324Cooperative ClassificationH01L21/67115, H01L21/324, H01L21/681European ClassificationH01L21/67S2H6, H01L21/324, H01L21/68LLegal EventsDateCodeEventDescriptionOct 12, 2011FPAYFee paymentYear of fee payment: 4RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google