JP2005053121A - Core for mold, mold and mold manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold having a fine and ultraprecise structure capable of certainly molding a molded product having a fine and ultraprecise part, easy to manufacture and capable of being molded inexpensively to provide a fine and ultraprecise molded product having no error in its turn. <P>SOLUTION: This core for the mold is equipped with a silicon die geometrically processed by etching using a lighography technique. A fitting hole is bored in the cavity part surface of a template and a precise part block, which is formed by fixing the silicon die geometrically processed by etching using a lithography technique to a die base, is fitted in the fitting hole and the precise part block is fixed to the template by a screw to form the mold. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mold insert, a mold, and a method for manufacturing the mold. More specifically, the present invention relates to a mold insert for manufacturing a molded product having a fine and ultra-precise shape, a mold, and a method for manufacturing the mold.

  Molds used for injection molding methods and compression molding methods for molding synthetic resin, ceramic metal powder, etc. were cut and polished by machining, but only machining on the order of 1.0 μm is required for machining. Therefore, it is impossible to process a micrometer unit of less than 1.0 μm, and it is impossible to manufacture a mold for manufacturing a molded product having a micro shape of μm or less. It has been difficult to produce a molded product having a precise shape. However, at present, it is indispensable to manufacture a molded product having a fine and ultra-precise shape of μm or less by miniaturization and refinement of various devices, and a die for that purpose is required.

  As a mold that enables the production of molded products with such a fine and ultra-precise shape, a resist is applied onto the polymer, a desired resist pattern is formed by lithography, and then the underlying polymer is etched using the resist pattern as a mask. Then, a master pattern is produced, nickel plating is applied to the master pattern, the plating layer is peeled off from the master pattern, and used as a mold (for example, refer to Patent Document 1), and a single crystal silicon substrate is used for photolithography technology. A recess is formed in the substrate by etching, and nickel is attached to the recess by electroforming or the like to obtain a replica, and the replica is used as a mold (see, for example, Patent Document 2), or The base material is coated with silicon as a protective layer, and further coated with chromium nitride. Preparative pattern is formed and developed, there is formed a mold chromium nitride is dry etched (for example, see Patent Document 3.).

  However, the former two perform etching using a lithography technique on a polymer or single crystal silicon substrate to form a master pattern or a master mold, and perform metal plating on the master pattern or the like to form a plating layer. It is used as a mold, and the master pattern formed by etching using lithography technology is not used as a mold, but the mold is manufactured by plating using the shape as a mother mold. The process of manufacturing a mold such as casting and peeling of a nickel plating layer is complicated, and there is a drawback that a fine and ultra-precision shape is deformed in the plating process and the peeling process of the plating layer.

  In the latter case, the mold itself is etched using a lithography technique, and it is difficult to uniformly apply a resist. In addition, it is difficult to perform fine and ultra-precision processing on a heavy and bulky mold. In addition, it is necessary to increase the size of a machine for coating a chromium nitride film and a machine for etching, which increases costs and is not easy. Further, even when it is desired to process a part of the molded product minutely and ultra-precisely, it is necessary to coat the entire cavity surface of the mold, which has the disadvantage of not being efficient.

JP-A-8-238631 JP20011333772 JP 2002-338271 A

  Therefore, the present invention eliminates the above-mentioned conventional drawbacks, and is a mold having a fine and ultra-precision structure that can reliably mold a molded product having a fine and ultra-precision portion, and can be manufactured easily and inexpensively. The object is to provide a mold and, in turn, a fine and ultra-precision molded product free from errors.

  A first means for solving the above-described problems is a mold nesting characterized by including a silicon die whose shape is processed by etching using a lithography technique.

  The second means is a mold characterized in that a silicon die shaped by etching using a lithography technique is fixed to a cavity surface of a mold plate.

  The third means is characterized in that a fitting hole is drilled in the cavity surface of the template, and a silicon die that has been processed by etching using a lithography technique is fitted into the fitting hole. It is a mold to do.

  The fourth means is a mold characterized in that, in the third means, the precision part block formed by fixing the silicon die to the die base is fitted into the fitting hole.

  The fifth means is a mold according to the fourth means, wherein the precision block is fixed to the mold plate with a screw.

  The sixth means is a mold manufacturing method characterized by forming a silicon die by etching using a lithography technique to fix the silicon die to the cavity surface of the mold plate.

  The seventh means is to form a silicon die by drilling a fitting hole in the cavity surface of the template, etching the shape using a lithography technique, and fitting the silicon die into the fitting hole. This is a method of manufacturing a mold.

  Further, the eighth means is the mold manufacturing method according to the seventh means, wherein the precision die block is formed by fixing the silicon die to the die base, and the precision portion block is fitted into the fitting hole. It is.

  According to a ninth means, in the eighth means, the mold plate and the die base are perforated with screw holes, and screws are screwed into the screw holes to fix the mold plate and the precision part block. This is a mold manufacturing method.

  According to the present invention, it is possible to easily and inexpensively manufacture a mold having a fine and ultra-precision structure capable of reliably molding a molded product having a fine and ultra-precision portion. In addition, it is possible to manufacture a molded product having a fine and ultra-precise part with no error. Furthermore, since the precision part block is fixed to the mold plate with screws, the precision part block can be easily removed. Therefore, the precision part block can be easily replaced, and the mold can be worn due to wear of the precision machined part of the mold. Molds can be manufactured easily and inexpensively without the need to replace the whole. Molds with different precision parts only can be handled by replacing the precision part block, and the mold does not have to be replaced. Can be manufactured easily and inexpensively.

  Embodiments of the present invention will be described below with reference to the drawings. The mold 1 is composed of a fixed mold 2 and a movable mold 3. The movable mold 3 has a fitting hole 4 formed in a mold plate 31, and the fitting hole 4 is processed into a precise shape. A precision part block 56 composed of a die base 6 to which a silicon die 5 is bonded is embedded.

  Fixed side mold 2 and movable side mold 3 In other words, the mold plate 21 and the mold plate 31 are formed by molding a shape other than the precision portion of the molded product by conventional machining and filling the molding material to form the molded product. The fitting hole 4 is drilled at a position corresponding to the surface of the mold plate 31 of the movable mold 3 constituting the cavity portion 11, that is, the portion of the cavity portion surface 311 of the mold plate 31 that is to be precision processed. The shape of the fitting hole 4 is formed into a shape that allows the precision portion block 56 to be fitted in correspondence with the shape of the precision portion block 56.

  The die base 6 inserted and fitted into the fitting hole 4 is a block body manufactured using the same material as that of the mold plate 21 and the mold plate 31, for example, die steel, super steel, and other steel used for the mold. is there. The reason why the die base 6 is used is that the silicon die 5 is thin, brittle and fragile, so that it is integrated with the die base 6 to increase the strength of the silicon die 5.

  The silicon die 5 is formed using a single crystal silicon wafer 80. The silicon purity of the silicon wafer 80 used for forming the silicon die 5 is not particularly limited, and does not have to be high purity required for silicon for manufacturing ICs.

  The silicon die 5 is manufactured by applying processes such as a semiconductor manufacturing method, lithography and etching as follows. FIG. 2 is a manufacturing process diagram of the silicon die 5. First, a single crystal silicon ingot is cut by a wire saw method or the like, and the surface is polished to produce a silicon wafer 80 having a thickness of about 0.3 to 1.0 mm (a). A photoresist 90 is dropped on the upper surface of the silicon wafer 80 using a coater, the wafer is rotated at a high speed to apply a resist thin film (b), and the silicon wafer 80 is set on a stepper and passed through a mask on which a precise shape is baked. The photoresist 90 is irradiated with a laser beam 91 for exposure (c), developed to form a photoresist pattern (d), and the photoresist 90 is baked and hardened at a temperature of about 150 ° C. Using the photoresist 90 as a mask, the silicon wafer 80 is dry etched (e) to form a precision shape 55 (f). Thereafter, the remaining photoresist 90 is ashed using oxygen plasma and acid cleaned (g). Then, the silicon wafer 80 is diced with a diamond blade 93 (h) to manufacture the silicon die 5 on which the precision shape 55 is formed (i). The silicon die 5 is manufactured by repeating the steps (b) to (f) according to the precise shape.

  The above is an outline of one embodiment of the manufacturing process of the silicon die 5. In this process, the photoresist 90 may be a positive type or a negative type, and other types may be used as a light source during exposure. A direct beam writing apparatus may be used, other methods may be used for dry etching, and normal lithography and IC manufacturing processes, means, and materials such as pre-baking after specific processes are appropriately selected. Is possible.

  2 is a manufacturing process of the silicon die 5 having the concave shape 55 when the precision shape of the molded product is a convex shape. By changing the resist pattern, changing the position of the dicing, etc. Protruding and forming appropriate portions of the silicon die 5, that is, manufacturing the silicon die 5 having a convex shape by etching around the portion to be projected, or manufacturing a molded product having a concave precise shape, or silicon Producing appropriate portions of the die 5 in a convex shape and forming the appropriate portions in a concave shape to manufacture a silicon die 5 having a convex shape and a concave shape, and manufacturing a molded product having a concave shape and a precise shape of the convex shape. Is possible. Of course, the concave shape and the convex shape of the silicon die 5 can be formed in a stepped shape.

  Next, the silicon die 5 manufactured as described above is fixed on the die base 6 using an adhesive 7 such as polyimide or silicon resin to manufacture the precision block 56, and the precision portion 56 is inserted into the fitting hole 4 of the template 31. The block 56 is embedded and the movable mold 3 is configured. The fitting hole 4 and the precision block portion 56 can be joined using an adhesive such as polyimide or silicone resin, but the screw 8 is screwed into the screw holes 32 and 61 provided in the template 31 and the die base 6. It is recommended to do this. Further, it is recommended that the template 31 be provided with a recess 52 for accommodating the head 88 of the screw 8 to prevent the head 88 from protruding. By fixing the precision block portion 56 to the template 31 using the screws 8, the precision block portion 56 can be easily attached and detached, and a new silicon die 5 is installed when the silicon die 5 is worn or damaged. Is easily possible. Moreover, it becomes possible to manufacture a molded article having a different shape by installing the silicon die 5 having precision portions having different shapes.

  Further, the cross section and bottom surface of the silicon die 5 and the top surface and cross section of the die base 6 have the same shape, so that the strength of the silicon die 5 can be strengthened and the precision block 56 can be embedded in, combined with, and removed from the template 31. From the viewpoint of. Further, when the precision part block 56 is fitted into the fitting hole 4, the precision part block 56 or the silicon die 5 is completely disposed so that the side surfaces of the silicon die 5 do not form the cavity part surfaces 211 and 311. It is embedded in the fitting hole 4 so that no step is generated at the joint between the silicon die 5 and the mold plates 21 and 31, and the cavity surface surfaces 211 and 311 of the mold plate 21 or 31 and the upper surface of the silicon die 5 are flush with each other. It is desirable to form the shape of the precision part block 56 and the fitting hole 4.

  The fitting hole 4 is drilled in the cavity part surface 211 of the template 21 and the precision part block 56 in which the silicon die 5 is bonded on the die base 6 is embedded in the template 21 or the cavity part surface 211 of the template 21 is embedded. Further, fitting holes 4 and 4 are formed in both of the cavity portion surface 311 of the template 31 and the precision portion block 56 in which the silicon die 5 is bonded to the die base 6 is embedded. Further, the cavity portion surface 211 of the template 21 and A precision in which an arbitrary number of fitting holes 4, 4... Are drilled at arbitrary locations where precise processing of a molded product is desired regardless of the cavity surface 311 of the template 31, and the silicon die 5 is bonded to the die base 6. The partial block 56 may be embedded.

  By manufacturing the silicon die 5 according to the size of the precision part of the molded product, it becomes possible to manufacture a molded product having a desired precision part. However, the size (area) of the silicon wafer 80 is limited and desired. If the size of the precision part cannot be secured, the precision part block 56 is placed adjacent to the mold plate 21 or 31 so that the mold part for producing the desired precision part can be manufactured.

  The silicon die 5 or the precision block 56 manufactured in this way can be used as a mold insert. Further, without forming the precision block 56 as described above, the silicon die 5 is bonded to the cavity surface 211 of the mold plate 21 and / or the cavity surface 311 of the mold 31 using an adhesive such as polyimide or silicon resin. The mold 1 can be configured by fixing the mold 1 or the mold plate 21 or / and the mold plate 31 is provided with a fitting hole 4, and the silicon die 5 is inserted into the fitting hole 4 without using the die base 6. 21 and / or the template 31 may be directly embedded and fixed with an adhesive or the like.

Cross section of mold according to one embodiment of the present invention The present invention silicon die manufacturing process diagram

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 11 Cavity part 2 Fixed side mold 21 Mold plate 3 Movable side mold 31 Mold plate 4 Fitting hole 5 Silicon die 6 Die base 56 Precision block 7 Adhesive 8 Screw 80 Silicon wafer 90 Photoresist

Claims (9)

  A mold nesting comprising a silicon die that has been processed by etching using a lithography technique.   A mold characterized by being formed by fixing a silicon die shaped by etching using a lithography technique to a cavity surface of a mold plate.   A die characterized in that a fitting hole is formed in a cavity portion surface of a mold plate, and a silicon die having a shape processed by etching using a lithography technique is fitted into the fitting hole.   4. The mold according to claim 3, wherein a precision part block formed by fixing a silicon die to a die base is fitted into a fitting hole.   5. The mold according to claim 4, wherein the precision block is fixed to the mold plate with screws.   A die manufacturing method comprising forming a silicon die by etching using a lithography technique to fix the silicon die to a cavity surface of a mold plate.   A mold manufacturing method characterized by drilling a fitting hole in the cavity surface of a mold plate, forming a silicon die by etching using a lithography technique, and fitting the silicon die into the fitting hole. Method.   8. The mold manufacturing method according to claim 7, wherein a silicon die is fixed to the die base to form a precision block, and the precision block is fitted into the fitting hole.   9. The mold manufacturing method according to claim 8, wherein a screw hole is drilled in the mold plate and the die base, and a screw is screwed into the screw hole to fix the mold plate and the precision part block.

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