JP2010052168A - Method and apparatus for molding synthetic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for molding a synthetic resin which can accurately mold molding parts on a substrate by suppressing positional dislocation. <P>SOLUTION: In the synthetic resin molding method, after a plurality of the molding parts 55 are molded simultaneously on the substrate 50 by pressing the synthetic resin 54 softened or liquefied by heating by using a stamper mold 60, a cooling process is implemented. In the cooling process, a gradient is formed in the in-plane temperature distribution of the stamper mold 60 and the substrate 50, and the temperature of the vicinity of the central part b is made to be lower than the temperature of the peripheral part. Cooling pipes 74 are installed in a stage 61 holding the stamper mold 60 and a stage 62 holding the substrate 50, respectively. The respective cooling pipes 74 are arranged so that a coolant may flow from the vicinity of the central part b toward the peripheral part while spreading. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a synthetic resin molding method and apparatus.

  Conventionally, for example, an opto-electric conversion device described in Patent Document 1 is mounted with a mount substrate on which a light emitting element that converts an electrical signal into an optical signal is mounted, and a light receiving element that converts the optical signal into an electrical signal. Each mounted substrate is mounted on a wiring substrate via a circuit substrate.

  In this photoelectric conversion device, waveguides that are optically coupled to the light-emitting element or the light-receiving element are formed on the mount substrate, respectively, and these waveguides extend from the mount substrate and extend from each other at the tips. They are connected to each other by connectors.

  The waveguide of the mount substrate as described above is generally formed as follows. Using a circular silicon substrate (silicon wafer) 50 as shown in FIG. 6A, a plurality (15 in this example) of mount substrates 51 are formed at the same time as separated by a one-dot chain line. Finally, the silicon substrate 50 is cut at the position of the one-dot chain line, and the mount substrate 51 is singulated as shown in FIG.

  First, as shown in FIG. 7A, a waveguide forming groove 52 (including a mirror part 53 inclined at 45 degrees) is formed at the position of the mount substrate 51 of the silicon substrate 50. Then, as shown in FIG. 7B, the waveguide forming groove 52 is filled (or coated. The same applies hereinafter), and then, as shown in FIG. (Not shown) to press the lower clad material 54 to form the core groove 55. As shown in FIG. 7D, the core material 55 is filled into the core groove 55 to form the core 56. Finally, as shown in FIG. 7E, the upper clad material 57 is placed on the core 56. By applying and forming the clad 58, the waveguide 59 is formed by the core 56 and the clad 58.

  In FIG. 8, the waveguide forming grooves 52 of the silicon substrate 50 are filled with the lower clad material 54, which is a thermoplastic resin, and then the lower clad material 54 is pressed using the stamper mold 60, and the core groove 55. It is process drawing which forms.

  As shown in FIG. 8A, the stamper mold 60 is sucked and held on the fixed upper stage 61 and the silicon substrate 50 is sucked and held on the movable lower stage 62 in a normal temperature (about 23 ° C.) state.

  The waveguide forming groove 52 of the silicon substrate 50 is filled with a lower cladding material 54. In this state, the lower cladding material 54 is heated (about 90 ° C.) together with the stamper mold 60 and the silicon substrate 50. Soften or liquefy.

  Thereafter, as shown in FIG. 8B, the alignment marks (see reference symbol “a” in FIG. 9) on both the left and right sides of the silicon substrate 50 and the stamper mold 60 are monitored by the corresponding cameras 63, respectively. Then, the midpoint coordinates of the left and right alignment marks [see symbol b in FIG. ] Match so that the silicon substrate 50 and the stamper mold 60 are moved in a horizontal plane against the adsorption holding force. Thereby, the center part (center of gravity position) of the stamper mold 60 and the silicon substrate 50 coincides.

  After the positional alignment between the silicon substrate 50 and the stamper mold 60 is completed in this way, the lower stage 62 is raised as shown in FIG. Press with mold 60. As a result, the core groove (molded portion) 55 is formed in the lower clad material 54. In FIG. 9A, which will be described later, the portion indicated by the black square mark is the waveguide forming groove 52. In this example, the 57 waveguide forming grooves 52 of the silicon substrate 50 have the core grooves ( The molding part) 55 is formed at the same time.

  Then, with 57 core grooves 55 formed at the same time, as shown in FIG. 8 (d), it is cooled and solidified to a mold release temperature (about 35 ° C.).

  Thereafter, as shown in FIG. 8C, the lower stage 62 is lowered and the stamper mold 60 is released from the lower clad material 54 of the silicon substrate 50, as shown in FIG. A core groove 55 is formed in the lower clad material 54.

  9A is a plan view in which the stamper mold 60 and the silicon substrate 50 are sucked and held on the upper and lower stages 61 and 62, respectively. FIG. 9B to FIG. It is a principal part expanded sectional view of the XX part of 9 (a). As described above, in the example of FIG. 9A, the core grooves (molded portions) 55 are simultaneously formed in the 57 waveguide forming grooves 52 of the silicon substrate 50 at the positions of the black square marks.

  FIG. 9B shows the suction holding process of FIG. 8A, in which the stamper mold 60 and the silicon substrate 50 are sucked and held on the upper and lower stages 61 and 62, respectively. In this case, each core groove forming convex portion 60a of the stamper mold 60 is aligned with each waveguide forming groove 52 in combination with the alignment step of FIG. 8B.

  FIG. 9C is the pressing step of FIG. 8C, and the stamper mold 60 and the silicon substrate 50 to be heated expand outward. In this case, the thermal expansion is small at the position of the midpoint coordinate b which is the center of the stamper mold 60 and the silicon substrate 50. However, at the peripheral position c, thermal expansion increases, and the position of the core groove forming convex portion 60a of the stamper mold 60 with respect to the waveguide forming groove 52 shifts outward, so that the core groove 55 is formed. A positional deviation d occurs.

  FIG. 9D is a cooling process of FIG. 8D, and the stamper mold 60 and the silicon substrate 50 to be cooled are thermally contracted inward. FIG. 9D shows a state in which the core groove forming convex portion 60a of the stamper mold 60 is accurately thermally contracted by the positional deviation d of the core groove 55 due to thermal expansion.

  FIG. 9E shows the mold release step of FIG. 8E and shows a state in which there is no positional deviation d in the core groove 55.

Here, in the case of molding (imprint) using a thermosetting resin that does not require heating / cooling steps or a photocurable resin that can perform all steps at room temperature, there is no thermal expansion or shrinkage as described above. Therefore, the position accuracy of the core groove (molding portion) 55 is determined by the alignment accuracy in the alignment process of FIG. 8B and the overlay accuracy of the molding apparatus, and is generally at a predetermined position on the silicon substrate 50. Molding is possible with high accuracy (± several um).
JP 2003-222746 A

  However, in the case of molding (imprint) using a thermoplastic resin or the like that requires a heating / cooling process, there is thermal expansion or contraction as described above. Therefore, as shown in FIG. 10, due to the shrinkage of the stamper mold 60 and the silicon substrate 50 during the cooling process, due to the in-plane variation of friction between the adsorption interfaces between the upper and lower stages 61 and 62, There is a possibility that a positional deviation d may occur. In FIG. 10, the white square mark position represents the normal position, and the black square mark position represents the position where the positional deviation d has occurred. The positional deviation d indicates a center of gravity deviation e and a rotational deviation f, and no pitch deviation due to a change in the mold shape pitch dimension due to thermal contraction.

  As a result, there is a problem that it is difficult to mold the core groove (molded portion) 55 at a predetermined position of the silicon substrate 50 with high accuracy (± several um).

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a synthetic resin molding method and apparatus that can form a molded part on a substrate with high accuracy while suppressing displacement. To do.

  In order to solve the above-mentioned problems, the present invention provides a synthetic resin that involves a cooling step after simultaneously molding a plurality of molded parts on a substrate by pressing a synthetic resin softened or liquefied by heating with a stamper mold. A method of molding a synthetic resin, characterized in that, in the cooling step, a gradient is applied to the in-plane temperature distribution of the stamper mold and the substrate, and the temperature near the center is lower than that of the periphery. It is to provide.

  Further, the present invention is a synthetic resin molding apparatus that includes a cooling step after simultaneously molding a plurality of molded parts on a substrate by pressing a synthetic resin softened or liquefied by heating with a stamper die. The stage holding the stamper mold and the stage holding the substrate are each provided with a cooling pipe, and each cooling pipe is arranged so that the refrigerant flows from the vicinity of the center toward the periphery. The present invention provides a molding apparatus for synthetic resin.

  As in claim 3, in claim 2, it is preferable that a heating means capable of heating the periphery of each stage is provided.

  As in claim 4, in claim 3, the heating means is preferably a ring heater.

  According to the method of the present invention, in the cooling step, the temperature of the stamper mold and the vicinity of the central portion of the substrate is lowered before the peripheral portion, so that the synthetic resin near the central portion comes before the synthetic resin in the peripheral portion. The center of gravity can be fixed first by cooling and hardening. Therefore, since the positional deviation between the stamper mold and the substrate due to the shrinkage during cooling can be suppressed, the molding part can be molded on the substrate with high accuracy.

  According to the apparatus of the present invention, in the cooling process, the refrigerant in the cooling pipe receives the ambient heat as it flows from the vicinity of the central part toward the peripheral part. The center of gravity can be fixed first by being cooled and hardened before the synthetic resin in the peripheral portion. Therefore, since the positional deviation between the stamper mold and the substrate due to the shrinkage during cooling can be suppressed, the molding part can be molded on the substrate with high accuracy. In addition, since only the shape of the cooling pipe and the position of the entrance / exit are devised, the structure is simple and the apparatus cost is low.

  According to the third aspect, since the peripheral portion of each stage is heated by the heating means, it is possible to cool the peripheral portion at a temperature higher than that in the vicinity of the central portion. It is cooled before the resin and cured.

  According to the fourth aspect, by using a ring heater as the heating means, heating can be performed easily and at low cost.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  First, the in-plane temperature distribution of the stamper mold 60 and the silicon substrate 50 in the cooling process will be described.

  11A is a plan view of the upper stage 61, FIG. 11B is a cross-sectional view of the upper stage 61, the stamper mold 60, the silicon substrate 50, and the lower stage 62, and FIG. FIG. FIG. 11D is a plan view of the state in which the stamper mold 60 and the silicon substrate 50 are sucked and held by the upper and lower stages 61 and 62, respectively, from the top, similarly to FIG. 9A. Moreover, Fig.12 (a) is an enlarged view of FIG.11 (b) in a press process, FIG.12 (b) is an enlarged view of FIG.11 (b) in a cooling process.

  The upper stage 61 is provided with a U-shaped cooling pipe 70 that is lateral in FIG. 11A, and the lower stage 62 is provided with a U-shaped cooling pipe 71 that is downward in FIG. 11C. To do. As the refrigerant (water or oil) flowing through the cooling pipes 70 and 71 flows from IN (inlet) to OUT (outlet), the temperature of the refrigerant increases due to ambient heat. Therefore, as seen from FIG. 11 (d), a left-side A portion that is easily cooled and a right-side B portion that is hardly cooled are surrounded by an elliptical line.

  For this reason, in the cooling process, as shown in FIG. 12A, the left side A has a lower temperature than the right side B, and the lower clad material (thermoplastic resin) 54 on the left side A is lower than the lower clad material 54 on the right side B. It is first cooled and solidified (high viscosity). As a result, as shown in FIG. 12B, the stamper mold 60 and the silicon substrate 50 are thermally contracted in the direction of the left side A. Then, the position (center of gravity) of the midpoint coordinate b that becomes the center of the stamper mold 60 and the silicon substrate 50 moves to b ′, and a position shift d (particularly center of gravity shift e) occurs in the core groove 55. . Depending on the cooling condition, a rotational deviation f may also occur.

  Therefore, in the present invention, attention is paid to the in-plane temperature distribution of the stamper mold 60 and the silicon substrate 50 in the cooling process.

  FIG. 1 is a method of the first embodiment (basic configuration) for providing a gradient (difference) in the in-plane temperature distribution of the stamper mold 60 and the silicon substrate 50, and is an enlarged view of FIG. 11B in the cooling process. is there.

  In FIG. 1, the curve C of the in-plane temperature distribution of the central part b and the peripheral part of the stamper mold 60 and the silicon substrate 50 is shown together, and the central part b is made lower in temperature than the peripheral part.

  Assuming that the silicon substrate 50 is, for example, a 4-inch silicon wafer, the stamper mold 60 is preferably an octagonal nickel electroforming stamper (thickness of about 300 μm to 500 μm) having an opposite side length of 100 mm.

  In the case of the configuration of the first embodiment, the temperature of the stamper mold 60 and the vicinity of the central portion b of the silicon substrate 50 is lowered before the peripheral portion in the cooling step. Thereby, the lower clad material 54 in the vicinity of the central portion b is cooled and hardened before the lower clad material 54 in the peripheral portion, whereby the center of gravity (the central portion b) can be fixed first. Accordingly, since the positional deviation d between the stamper mold 60 and the silicon substrate 50 due to the shrinkage during cooling can be suppressed, the core groove (molded portion) 55 can be formed in the silicon substrate 50 with high accuracy.

  Here, a synthetic resin softened or liquefied by heating is pressed with a stamper mold 60 to simultaneously mold a plurality of molded parts, and then a thermoplastic resin is generally used as a synthetic resin with a cooling step. is there. Examples of the thermoplastic resin include those used for nanoimprint such as acrylic resin (PMMA), polycarbonate resin (PC), cyclic olefin copolymer (COC), and cycloolefin copolymer (COP).

  In addition to this thermoplastic resin, it contains an epoxy compound that is solid at room temperature and an epoxy compound that is liquid at room temperature in a predetermined ratio, further contains a photopolymerization initiator, and melts or softens by heating, and is solid at room temperature. A photocurable resin (so-called solid uncured resin) can also be used.

  2A and 2B show an apparatus according to the second embodiment, in which FIG. 2A is a plan view of the upper stage 61, and FIG. 2B is an upper stage 61, a stamper mold 60, a silicon substrate 50, and a lower stage 62. A sectional view and FIG. 2C are plan views of the lower stage 62.

  In the upper stage 61 and the lower stage 62, an inlet (IN) 74a of the cooling pipe 74 is formed in the vicinity of the central portion b. Each stage 61, 62 is provided with cooling pipes 74 at equal angular intervals (45 degrees in this example) radially from the vicinity of the central portion b toward the peripheral portion. The outlets (OUT) 74b of the radial cooling pipes 74 are formed on the side surfaces.

  3A and 3B show an apparatus according to the third embodiment. FIG. 3A is a plan view of the upper stage 61, and FIG. 3B is an upper stage 61, a stamper mold 60, a silicon substrate 50, and a lower stage 62. A sectional view and FIG. 3C are plan views of the lower stage 62.

  In the upper stage 61 and the lower stage 62, an inlet (IN) 75a of the cooling pipe 75 is formed in the vicinity of the central portion b. Each stage 61, 62 is provided with a cooling pipe 75 spirally from the vicinity of the central portion b toward the periphery, and an outlet (OUT) of the spiral cooling pipe 75 is provided on one side surface of each stage 61, 62. 75b is formed.

  FIG. 4 shows a configuration in which the refrigerant is supplied to the inlet 74a of the cooling pipe 74 formed in the vicinity of the central portion b of the upper stage 61 and the lower stage 62 of the first embodiment. In addition, since the structure which supplies a refrigerant | coolant to the inlet_port | entrance 75a of the cooling pipe 75 of 2nd Embodiment is also the same, description is abbreviate | omitted.

  4A is a plan view of the lower stage 62, and FIG. 4B is a side sectional view of the lower stage 62. 4C is a plan view of the upper and lower stage auxiliary plates 76, and FIG. 4D is a side sectional view of the upper and lower stage auxiliary plates 76. FIG. 4E is a side sectional view of the upper and lower stages 61 and 62 to which the auxiliary plates 76 are respectively attached.

  4A and 4B, the upper surface of the lower stage 62 is an adsorption holding surface of the silicon substrate 50, and the inlet (IN) 74a of the cooling pipe 74 is formed on the lower surface near the central portion b.

  4C and 4D, an outlet 77b of the refrigerant supply pipe 77 is formed on the upper surface near the central portion b of the auxiliary plate 76, and an inlet 77a of the refrigerant supply pipe 77 is formed on one side of the auxiliary plate 76. ing. In addition, since the structure of the upper stage 61 and the auxiliary | assistant plate 76 is also the same, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In FIG. 4E, when the refrigerant is supplied from the inlet 77a of the refrigerant supply pipe 77 of each auxiliary plate 76 of the upper and lower stages 61, 62, the refrigerant is supplied from the outlet 77b of the refrigerant supply pipe to the upper and lower stages 61, 62. 62 enters the cooling pipe 74 through the inlet 74a. Then, the radial (or spiral) cooling pipe 74 flows while expanding toward the outlet 74b, and is discharged from the outlet 74b.

  If it is the structure of 2nd, 3rd embodiment, in a cooling process, the refrigerant | coolant of the cooling pipes 74 and 75 will receive ambient heat, and will go up, so that it flows toward the periphery from the center part b vicinity. . Therefore, the lower clad material 54 in the vicinity of the central portion b is cooled and solidified earlier than the lower clad material 54 in the peripheral portion, so that the center of gravity (central portion b) can be fixed first. Accordingly, since the positional deviation d between the stamper mold 60 and the silicon substrate 50 due to the shrinkage during cooling can be suppressed, the core groove (molded portion) 55 can be formed in the silicon substrate 50 with high accuracy.

  Further, since the shape of the cooling pipes 74 and 75 and the positions where the inlets and outlets 74a, 74b, 75a and 75b are formed are devised, the structure is simple and the apparatus cost is reduced.

  5A and 5B show an apparatus according to the fourth embodiment. FIG. 5A is a plan view of the lower stage 62, and FIG. 5B is a side sectional view of the lower stage 62. FIG. 4C is a side sectional view of the upper and lower stages 61 and 62 to which the auxiliary plate 76 is attached. In addition, since the cooling pipe 74 and the auxiliary | assistant plate 76 are the same as the structure of Fig.4 (a)-(e), the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the fourth embodiment, a heating means capable of heating the peripheral portions of the upper and lower stages 61 and 62 is provided, and a ring-shaped heater 78 is used as the heating means. The ring heater 78 is disposed above the cooling pipe 74 in the upper and lower stages 61 and 62 (on the silicon substrate 50 side and the stamper mold 60 side), but may be located on the lower side. Further, it may be arranged in the auxiliary plate 76.

  If it is the structure of 4th Embodiment, the surrounding part of the upper and lower stages 61 and 62 can be cooled by the ring-shaped heater 78, and the temperature of the surrounding part can be cooled in the state made higher than the center part b vicinity. Therefore, the lower clad material 54 near the central portion b is surely cooled and hardened before the lower clad material 54 in the peripheral portion. Moreover, by using the ring-shaped heater 78 as a heating means, it can be heated easily and at low cost.

It is 1st Embodiment of this invention, and is the side surface sectional drawing of the stamper metal mold | die and silicon substrate in a cooling process which showed the state which gives a gradient to in-plane temperature distribution. It is 2nd Embodiment of this invention, (a) is a top view of an upper stage, (b) is sectional drawing of an upper stage, a stamper metal mold | die, a silicon substrate, and a lower stage, (c) is a top view of a lower stage is there. It is a third embodiment of the present invention, (a) is a plan view of the upper stage, (b) is a sectional view of the upper stage, stamper mold, silicon substrate, lower stage, (c) is a plan view of the lower stage is there. It is the structure which supplies a refrigerant | coolant to the inlet_port | entrance of the center part of an upper and lower stage, (a) is a top view of a lower stage, (b) is side surface sectional drawing of a lower stage, (c) is a top view of an auxiliary plate, (d ) Is a side sectional view of the auxiliary plate, and (e) is a side sectional view of the upper and lower stages to which the auxiliary plate is attached. FIG. 4A is a plan view of a lower stage, FIG. 5B is a side sectional view of the lower stage, and FIG. 5C is a side sectional view of an upper and lower stage with an auxiliary plate attached thereto. (A) is a perspective view of a silicon substrate, (b) is a perspective view of a mount substrate. (A)-(e) is process drawing which forms a waveguide in the position of the mount substrate of a silicon substrate. (A)-(e) is process drawing which forms the groove | channel for cores. (A)-(e) is explanatory drawing in the process of FIG. It is explanatory drawing which shows the position shift of the groove | channel for cores. (A)-(d) is a figure explaining the in-plane temperature distribution in a cooling process. (A) is an enlarged view of FIG.11 (b) in a press process, (b) is an enlarged view of FIG.11 (b) in a cooling process.

Explanation of symbols

50 Silicon substrate 51 Mount substrate 52 Waveguide forming groove 54 Lower clad material (thermoplastic resin)
55 Core groove 58 Clad 59 Waveguide 60 Stamper mold 60a Core groove forming convex part 61 Upper stage 62 Lower stage 74 Radial cooling pipe 75 Helical cooling pipe 76 Auxiliary plate 77 Refrigerant supply pipe 78 Ring heater d Position Shift e Center of gravity shift f Rotation shift

Claims (4)

A synthetic resin molding method involving a cooling step after simultaneously pressing a synthetic resin softened or liquefied by heating with a stamper mold and simultaneously molding a plurality of molding parts on a substrate,
In the cooling step, a synthetic resin molding method is characterized in that an in-plane temperature distribution of the stamper mold and the substrate is given a gradient so that the temperature in the vicinity of the central portion is lower than that in the peripheral portion. A synthetic resin molding apparatus with a cooling step after simultaneously molding a plurality of molding parts on a substrate by pressing a synthetic resin softened or liquefied by heating with a stamper mold,
A cooling pipe is provided on each of the stage holding the stamper mold and the stage holding the substrate, and each cooling pipe is arranged so that the refrigerant flows while spreading from the vicinity of the central portion toward the peripheral portion. A synthetic resin molding apparatus.   The synthetic resin molding apparatus according to claim 2, wherein heating means capable of heating a peripheral portion of each stage is provided.   The synthetic resin molding apparatus according to claim 3, wherein the heating means is a ring heater.

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