JP4773216B2 - Substrate transport method - Google Patents

Description

The present invention relates to a method of transporting a substrate such as a photomask, mask blank, or substrate used for manufacturing a semiconductor integrated circuit or a liquid crystal display device in a state in which the substrate is stored in a substrate storage case .

  When manufacturing a semiconductor integrated circuit, a liquid crystal display device, or the like, a transfer mask in which a transfer pattern made of a light-shielding film or the like is formed on a light-transmitting substrate is used in a process of patterning a thin film using a photolithography technique. In order to manufacture such a transfer mask, first, after forming a light-shielding film on the entire surface of the light-transmitting substrate, a resist layer is laminated on the entire surface of the light-shielding film. Next, the resist layer is selectively exposed, baked and developed to form a resist pattern, and then a light-shielding film is patterned using the resist pattern as a mask, and a transfer pattern is provided on the surface of the light-transmitting substrate. Manufacturing a transfer mask. Here, the mask blanks (or the mask) are used both in a stage where a metal layer such as a light-shielding film is formed on the entire surface of the translucent substrate and in a stage where a metal layer and a resist layer are stacked on the entire surface of the translucent substrate. Blank).

  For such substrates such as mask blanks, photomasks or substrates, when manufacturing, shipping, or transporting between manufacturing steps, for example, as shown in FIGS. A synthetic resin inner box 30 in which substrate holding grooves 32 into which both ends of the substrate are inserted are formed in the vertical direction, and a synthetic resin outer box 20 provided with an upper opening 21 for attaching and detaching the inner box 30. And the board | substrate storage case 10 provided with the synthetic resin lid | cover 40 covered on the upper opening 21 of this outer box 20 is used (refer patent document 1, 2).

Further, when the substrate 1 is transported using the substrate storage case 10, as shown in FIG. 10A, the bonding portion between the outer peripheral surface of the lid 40 and the outer peripheral surface of the outer box 20 is closed with an adhesive tape 60. Thereafter, as shown in FIG. 10B, the substrate storage case 10 is transported in a state of being stored in the case storage bag 50.
JP 2005-64279 A JP 2001-154341 A

  However, when the substrate 1 is transported by the method shown in FIGS. 10A and 10B, dust is generated due to friction between members during transport, and a large amount of dust adheres to the surface of the substrate 1. There is a point. Further, such dust causes contamination of the clean room. Further, when the dust adheres to the substrate 1 such as a photomask or mask blank, a serious defect such as a pattern defect or a decrease in transfer characteristics is generated.

  The present invention has been developed in view of such problems, and an object of the present invention is to provide a substrate transport method that can reliably prevent dust from adhering to the substrate surface during transport.

In order to solve the above-described problems, the present invention includes an inner box in which substrate holding grooves into which both ends of a substrate are inserted on opposite inner walls are formed in the vertical direction, and an upper opening for attaching and detaching the inner box. And a lid that covers the upper opening of the outer box so as to press the upper end of the substrate held in the substrate holding groove of the middle box housed in the outer box. In the method of transporting a substrate using a storage case, the substrate storage case is stored in a case storage bag, and the substrate storage case is bound by a band that is hung on both the outer box and the lid from above the case storage bag. all SANYO for transporting the substrate in a state, wherein in box, the outer box and the lid are both made of synthetic resin, said case storage bag, the metal layer is laminated to the outer surface of the cushion material layer made from a sheet material, before Substrate is a mask blank having a transfer pattern forming metal layer on the main surface, said substrate a bonding portion between the outer peripheral surface and the outer peripheral surface of the outer box of the lid in the substrate storage case in a state of closed with adhesive tape It is transported .

  In the present invention, the substrate storage case is stored in the case storage bag, and the substrate storage case is transported in a state in which the substrate storage case is tied with a band hung on both the outer box and the lid from above the case storage bag. The outer box, the inner box, the substrate and the lid are not displaced and rubbed. Therefore, it is possible to reliably prevent dust from adhering to the substrate during conveyance.

Moreover, since the case storage bag is made of a sheet material in which a metal layer is laminated on the cushion material layer, it is possible to reliably prevent moisture from entering the substrate storage case from the outside.

Furthermore, the joint between the outer box and the lid of the substrate storage case containing the substrate can be sealed with an adhesive tape so that the joint between the outer box and the lid can be sealed without any gaps, so that foreign matter can enter the substrate storage case from the outside. Can be surely prevented.

The present invention is effective when applied as a substrate when transporting mask blanks in which a resist layer is laminated on the transfer pattern forming metal layer.

  In the present invention, since the substrate is transported in a state where the substrate storage case is bound by the bands hung on both the outer box and the lid, the outer box, the inner box, the substrate, and the lid are not displaced and rubbed during transportation. Therefore, it is possible to reliably prevent dust from adhering to the substrate during conveyance. Therefore, the clean room is not contaminated by dust generated during transportation. Further, since dust does not adhere to the photomask or mask blank, problems such as pattern defects and deterioration of transfer characteristics do not occur.

  Embodiments of the present invention will be described with reference to the drawings. In the following description, an example in which mask blanks are transferred as a substrate will be mainly described. Further, the basic configuration of the present invention is the same as that of the prior art described with reference to FIG. 10, and therefore common portions will be described using the same drawings.

[Embodiment]
(Structure of board storage case)
FIG. 1 is a perspective view of a substrate storage case and a case storage bag to which the present invention is applied. FIG. 2 is a perspective view showing a state in which the substrate is stored in the inner box shown in FIG. FIGS. 3A and 3B are a perspective view showing the inner surface of the lid and an explanatory view showing an enlarged substrate press formed on the lid.

  As shown in FIG. 1, the substrate storage case 10 includes an inner box 30 that holds the substrate 1 in a vertical posture therein, and an outer box 20 that has an upper opening 21 for attaching and detaching the inner box 30 at the upper part. The lid 40 covers the upper opening 21 of the outer box 20. Examples of the substrate 1 include a photomask, mask blanks and substrates that are used as the material. Here, the inner box 30, the outer box 20, and the lid 40 are made of various resin molded products such as polypropylene, acrylic, polyethylene, polyamide, and ABS.

  In the outer box 20, the peripheral edge 25 of the upper opening 21 is a slightly thick fitting part, and the outer peripheral part of the outer box 20 and the outer peripheral part of the lid 40 are fitted. In the outer box 20, a protrusion 27 is formed on the outside of the opposite side surfaces, and a hook 47 that engages with the protrusion 27 is formed on the lower end portion of the outer peripheral portion of the lid 40. In some cases, protrusions are formed on both the lid 40 and the outer box 20, and the lid 40 and the outer box 20 are fixed with separate hooks.

  In this embodiment, when the substrate 1 is transported using the substrate storage case 10, the substrate storage case 10 is stored in the case storage bag 50. Here, the case storage bag 50 is made of a sheet material in which a metal layer 3 such as aluminum is laminated on the outer surface of a cushion material layer such as a sheet-like foamed resin or an air cushion sheet, and has a moisture resistance function. Yes.

  As shown in FIGS. 1 and 2, in the inner box 30, substrate holding grooves 32 extending in the vertical direction are formed on the opposing inner walls 31, and the substrate 1 is moved along these substrate holding grooves 32. By inserting, the left and right ends of the substrate 1 are held in the substrate holding grooves 32. In this embodiment, a plurality of substrate holding grooves 32 are formed in parallel on the inner walls 31 facing each other in the inner box 30, for example, five in parallel, so that the inner box 30 can store five substrates 1. It has become. In addition, the board | substrate 1 accommodated in the inner box 30 may be one sheet. Here, the groove width of the substrate holding groove 32 is set to be slightly larger than the thickness dimension of the substrate 1 to be held, and a predetermined clearance is secured between the substrate 1 and the substrate holding groove 32. . Thereby, it is easy to insert the substrate 1 into and pull out the substrate 1 from the substrate holding groove 32, and to suppress damage to the substrate 1 due to friction and wear of the substrate holding groove 32.

  3A, on the inner surface of the lid 40, the upper end of the substrate 1 held in the substrate holding groove 32 of the inner box 30 when the lid 40 covers the upper opening 21 of the outer box 20 is formed. A substrate presser 41 for pressing the part is formed. In this embodiment, two rows of five substrate pressers 41 are formed at each of the positions where the upper end portions of the five substrates 1 are positioned, and the substrate 1 is pressed by the two substrate pressers 41 per one substrate 1. It is like that. As such a substrate holder 41, in this embodiment, as shown in FIG. 3B, an L-shaped resin molded product fixed to the inner surface of the lid 40 is used. A groove 410 having a trapezoidal cross section in which the upper end portion of the substrate 1 is fitted is formed in the lower end portion 411 in contact with 1. Moreover, since the board | substrate holding | suppressing 41 of this form has the groove | channel formed in both edge parts 411 and 412 of the L-shaped resin molded product, when fixing the board | substrate holding | suppressing 41 with respect to the inner surface of the lid | cover 40, By simply changing the orientation, the substrate holders 41 arranged in two rows can be formed of a common resin molded product.

(Conveying method of substrate 1)
FIG. 4 is a perspective view showing a state in which the outer case 20 is covered with the lid 40 in the substrate storage case 10 according to the present invention. FIGS. 5A, 5 </ b> B, and 5 </ b> C are vertical cross-sectional views illustrating the state of the substrate 1 in the substrate storage case 10. 6A, 6B, and 6C are perspective views illustrating a method of transporting the substrate 1 to which the present invention is applied.

  When the manufactured substrate 1 is shipped using the substrate storage case 10 to which the present invention is applied, or when it is transported between the manufacturing processes, as shown in FIG. After inserting the both ends of the substrate 1 and storing the plurality of substrates 1 in the inner box 30, the inner box 30 is stored in the outer box 20, and the upper opening 21 of the outer box 20 is covered with a lid 40. Further, as shown in FIG. 4, the hooks 47 of the lid 40 are engaged with the protrusions 27 of the outer box 20 to fix the lid 40 to the outer box 20.

  In this state, as shown in FIG. 5A, the lower end portion of the substrate 1 held in the substrate holding groove 32 of the inner box 30 is formed of a concave portion having a trapezoidal cross section formed in the bottom portion of the substrate holding groove 32. While supported by the receiving portion 320, the upper end portion of the substrate 1 is held in a groove 410 having a trapezoidal cross section formed in the substrate holder 41. Here, if the substrate 1 is a mask blank for forming a binary type photomask, a transfer mask is formed on the main surface of the insulating translucent substrate 2 made of synthetic quartz or fluorine-doped quartz glass. A metal layer 3 made of a chromium-based material or the like is formed, and a photosensitive resist layer 4 such as an acrylic resin is formed. Note that chamfered portions are formed at the end portions 1 a and 1 b of the translucent substrate 1.

  The mask blank shown in FIG. 5A is a type in which the photosensitive resist layer 4 is drawn with an electron beam. Therefore, in order to prevent charge-up at the time of drawing, the metal layer 3 is provided on the side of the translucent substrate 2. It is formed up to the end face. On the other hand, the photosensitive resist layer 4 is formed only in the inner region separated from the outer end of the substrate 1 by a predetermined distance.

  Here, if the substrate 1 is a mask blank of a type on which laser drawing is performed, it is not necessary to prevent charge-up, and therefore, as shown in FIG. 5B, the metal layer 3 is a side end surface of the translucent substrate 2. Has been removed from. In the case of a mask blank for forming a halftone mask, as shown in FIG. 5C, the halftone film 5, the metal layer 3, and the photosensitive resist layer 4 are formed on the translucent substrate 2. Is formed. Although not shown, in the case of a reflective mask blank, a metal layer or a resist layer is formed on the multilayer reflective film or the buffer layer on the low expansion substrate.

  In the example shown in FIGS. 5A, 5 </ b> B, and 5 </ b> C, the photosensitive resist layer 4 is removed from the outer end portion of the translucent substrate 2, but the outer end of the translucent substrate 2 is used. It may remain in the department.

  In either case, the insulating substrate 1 is in contact with the substrate holding groove 32 of the inner box 30 and the substrate pressing member 41 of the lid 40. For this reason, static electricity is generated during the transportation of the substrate 1, and when the substrate 1 is taken out from the substrate holding groove 32 or the lid 40 is removed during the transportation, a discharge occurs due to the static electricity accumulated so far. Since dust may be generated from the substrate holding groove 32 and the substrate holder 41 of the lid 40, it is preferable that the inner box 30 and the substrate holder 41 have conductivity. Such conductivity can be realized by adding a conductive filler such as carbon to the resin constituting the inner box 30 and the substrate holder 41. A part of the photosensitive resist layer 4 is also in contact with the substrate holding groove 32 of the inner box 30 and the substrate pressing member 41 of the lid 40.

  After the substrate 1 is stored in the substrate storage case 10 in this manner, first, as shown in FIG. 6A, the bonding portion between the outer peripheral surface of the lid 40 and the outer peripheral surface of the outer box 20 is covered with an adhesive tape 60. Block it. Next, as shown in FIG. 6B, the substrate storage case 10 is stored in the case storage bag 50. Next, as shown in FIG. 6C, the substrate storage case 10 is tied in a cross shape with a band 70 made of polypropylene tape or the like hung on both the outer box 20 and the lid 40 from above the case storage bag 50. In this state, the substrate 1 is transported.

  When carrying the substrate 1 into the clean room, first, after cutting the band 70 outside the clean room, the substrate storage case 10 is taken out of the case storage bag 50 and the substrate storage case 10 is carried into the clean room. Then, when the substrate 1 is used, the adhesive tape 60 is peeled off from the substrate storage case 10, and then the hook 47 is removed and the lid 40 is opened. Next, when the middle box 30 is taken out from the outer box 20 and set on the stage of the loader, the robot takes out the substrates 1 from the middle box 30 one by one.

(Main effects of this form)
As described above, in the method for transporting the substrate 1 according to the present embodiment, in the substrate storage case 10 that stores the substrate 1, the outer peripheral surface of the lid 40 that covers the upper opening 21 of the outer box 20 and the outer peripheral surface of the outer box 20. The joint portion is closed with the adhesive tape 60, and the joint portion between the outer box 20 and the lid 40 is sealed without a gap. The substrate storage case 10 is stored in the case storage bag 50. For this reason, it can prevent reliably that a foreign material penetrate | invades into the board | substrate storage case 10 from the outside during conveyance. Moreover, since the case storage bag 50 is made of a sheet material in which the metal layer 3 is laminated on the surface of the cushion material layer, it has high moisture resistance. Therefore, it is possible to reliably prevent moisture from entering the substrate storage case 10 from the outside during conveyance.

  Furthermore, in the method for transporting the substrate 1 according to this embodiment, the substrate storage case 10 is stored in the case storage bag 50 in a state where the joint portion between the outer peripheral surface of the lid 40 and the outer peripheral surface of the outer box 20 is closed with the adhesive tape 60. Then, the substrate 1 is transported in a state in which the substrate storage case 10 is bound by the band 70 hung on both the outer box 20 and the lid 40 from above the case storage bag 50. For this reason, it can prevent reliably that dust adheres to the main surface of the board | substrate 1 during conveyance compared with the method shown to Fig.10 (a), (b).

  For example, a mask blank having a photosensitive resist layer formed on a mask according to the present embodiment described with reference to FIGS. 6A to 6C and the conventional method described with reference to FIGS. In each of the packaged states, vibration was applied and the increase in the number of dust per substrate before and after that was repeatedly evaluated. According to the method of this embodiment, the average increase in the number of dust was 1.2. In contrast, in the conventional method, the average number was 30. In addition, said value is the number of the dust per sheet | seat of the several board | substrate 1 used for the test simultaneously. In addition, since this test was performed a plurality of times, the above values are average values of the numbers obtained in each test.

  As described above, according to the method of the present embodiment, it is possible to reliably prevent dust from adhering to the main surface of the substrate 1 during conveyance. The reason for this is that, in this embodiment, the substrate storage case 10 is bound by a band 70 that is hung on both the outer box 20 and the lid 40 from above the case storage bag 50, so that even if vibration is applied during transportation. The outer box 20, the lid 40, the inner box 30 and the substrate 1 are securely fixed to each other and do not shift, so that the lid 40 and the outer box 20 rub, the substrate 1 and the substrate presser 41 rub, It is considered that rubbing with the inner box 30 can be surely prevented.

  Further, in this embodiment, since the substrate storage case 10 is bound by the band 70 from above the case storage bag 50, a reference example (the substrate storage case 10) described below with reference to FIGS. Compared with the method of directly tying the band 70 with the band 70), even if vibration is applied during transportation, the band 70 is not displaced and loosened. Since it is not in contact with the box 20, there is an advantage that it does not generate dust.

  In this embodiment, when the substrate storage case 10 is transported into the clean room, the band 70 is removed outside the clean room. For this reason, even when the substrate storage case 10 is released from the state of being bound by the band 70, even when vibration or impact is applied to the substrate storage case 10 and dust is generated, the inside of the clean room is contaminated with such dust. It can be surely prevented.

(Another form of the substrate storage case 10)
In the above embodiment, the outer box 20 and the lid 40 are fixed by the hooks 47, but dust may be generated due to vibrations and shocks when the hooks 47 are removed in the clean room. On the other hand, the outer box 20 and the lid 40 are sealed and fixed with an adhesive tape 60. Therefore, as shown in FIG. 7, when the hook 47 is omitted from the substrate storage case 10 and the outer box 20 and the lid 40 are fixed only by the adhesive tape 60, dust when removing the hook 47 in the clean room is adopted. Occurrence can be prevented.

(How to hang band 70)
In the above embodiment, when the substrate storage case 10 is tied with the band 70 from above the case storage bag 50, the band 70 is hung so as to cross the cross. However, the band 70 may be hung on both the outer box 20 and the lid 40. For example, as shown in FIG. 8, corner portions of the substrate storage case 10 may be bound from above the case storage bag 50.

[Reference example]
FIGS. 9A, 9B, and 9C are perspective views showing a substrate transport method according to a reference example. Since the basic configuration of this embodiment is the same as that of the embodiment, common portions are denoted by the same reference numerals and description thereof is omitted.

  Also in this embodiment, as described with reference to FIGS. 1 to 4, when the manufactured substrate 1 is shipped using the substrate storage case 10 or when it is transported between the manufacturing steps, the inner box 30 is used. After inserting the both ends of the substrate 1 into the substrate holding groove 32 and storing the plurality of substrates 1 in the inner box 30, the inner box 30 is stored in the outer box 20 and the upper opening 21 of the outer box 20 is covered with the lid. Cover with 40. Further, as shown in FIG. 4, the hooks 47 of the lid 40 are engaged with the protrusions 27 of the outer box 20 to fix the lid 40 to the outer box 20.

  Further, as shown in FIG. 9 (a), the joint portion between the outer peripheral surface of the lid 40 and the outer peripheral surface of the outer box 20 is closed with an adhesive tape 60, and then, as shown in FIG. In a state where the substrate storage case 10 is bound by the band 70 hung on both the lid 40 and the lid 40, the substrate 1 is stored in the case storage bag 50 as shown in FIG.

  Even when the substrate 1 is transported by such a method, since the substrate 1 is transported in a state where the substrate storage case 10 is bound by the band 70 hung on both the outer box 20 and the lid 40, vibration is applied during the transport. However, the outer box 20, the lid 40, the inner box 30 and the substrate 1 are securely fixed to each other and do not shift. Therefore, rubbing between the lid 40 and the outer box 20, rubbing between the substrate 1 and the substrate presser 41, and rubbing between the substrate 1 and the inner box 30 can be prevented, so that dust adheres to the main surface of the substrate 1 during transportation. This can be prevented.

  When the substrate 1 is carried into the clean room, the substrate storage case 10 is taken out of the case storage bag 50 outside the clean room, the band 70 is cut, and then the substrate storage case 10 is carried into the clean room. When the storage case 10 is released from the state of being bound by the band 70, even if vibrations or impacts are applied to the substrate storage case 10 to generate dust, the inside of the clean room is reliably prevented from being contaminated by such dust. be able to.

  In this embodiment, the hook 47 may be omitted from the substrate storage case 10 as described with reference to FIG. 7, and the substrate storage case 10 is banded by the method described with reference to FIG. It may be tied with 70.

(Other embodiments)
In the above embodiment, the example of transporting mask blanks as the substrate 1 has been mainly described. However, the present invention may be applied to transport of a substrate 1 such as a photomask or a substrate in addition to the mask blanks.

It is a perspective view of a substrate storage case and a case storage bag to which the present invention is applied. It is a perspective view which shows a mode that a board | substrate is accommodated in the inner box shown in FIG. (A), (b) is a perspective view which shows the inner surface of the lid | cover shown in FIG. 1, and explanatory drawing which expands and shows the board | substrate holding | suppressing formed in this lid | cover. It is a perspective view which shows a mode that the outer case was covered with the lid | cover in the board | substrate storage case shown in FIG. (A), (b), (c) is a longitudinal cross-sectional view which shows the mode of the board | substrate in the board | substrate storage case shown in FIG. (A), (b), (c) is a perspective view which shows the conveyance method of the board | substrate which concerns on embodiment of this invention. It is a perspective view which shows the structure which abbreviate | omitted the hook from the board | substrate storage case in the board | substrate conveyance method to which this invention is applied. It is a perspective view which shows another method of hanging a band in the board | substrate conveyance method to which this invention is applied. (A), (b), (c) is a perspective view which shows the conveyance method of the board | substrate which concerns on a reference example. (A), (b) is a perspective view which shows the conveyance method of the conventional board | substrate.

DESCRIPTION OF SYMBOLS 1 Substrate 3 Metal layer 4 Resist layer 10 Substrate storage case 20 Outer box 21 Upper opening 30 of outer box 30 Middle box 32 Substrate holding groove 40 Lid 41 Substrate retainer 50 Case storage bag 60 Adhesive tape 70 Band

Claims (2)

An inner box in which substrate holding grooves into which both ends of the substrate are inserted in opposite inner walls are formed in the vertical direction, an outer box having an upper opening for attaching and detaching the inner box, and the outer box housed in the outer box In the method of transporting a substrate using a substrate storage case provided with a lid that covers the upper opening of the outer box so as to press the upper end of the substrate held in the substrate holding groove of the inner box,
The substrate storage case is stored in a case storage bag, and the substrate is transported in a state in which the substrate storage case is bound by a band hung on both the outer box and the lid from above the case storage bag. ,
The inner box, the outer box and the lid are all made of synthetic resin,
The case storage bag is made of a sheet material in which a metal layer is laminated on the outer surface of the cushion material layer,
The substrate Ri mask blank der having a transfer pattern forming metal layer on the main surface,
A substrate transporting method , wherein the substrate is transported in a state where a joint portion between the outer peripheral surface of the lid and the outer peripheral surface of the outer box is closed with an adhesive tape in the substrate storage case . The substrate transport method according to claim 1, wherein a resist layer is laminated on the transfer pattern forming metal layer.

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