TECHNICAL FIELD

The present invention relates to a method for molding a substrate storing container, a mold, and a substrate storing container which are used to store, keep, convey, or transport substrates formed of semiconductor wafers or the like.

BACKGROUND ART

In the related art, as a substrate storing container for storing and conveying substrates formed of semiconductor wafers in a factory process, there has been known a substrate storing container configured to include a container main body and a lid body (for example, refer to Patent Documents 1 to 4).

One end portion of the container main body has an opening circumferential portion in which a container main body opening portion is formed. The other end portion of the container main body has a tubular wall portion which is closed. A substrate storing space is formed inside the container main body. The substrate storing space is formed surrounded by the wall portion, and is capable of storing a plurality of substrates. The lid body is removably attached to the opening circumferential portion, and is capable of closing the container main body opening portion. Lateral substrate support portions are provided in the wall portion so as to form a pair in the substrate storing space. When the container main body opening portion is not closed by the lid body, the lateral substrate support portions are capable of supporting edge portions of the plurality of substrates in a state where the substrates adjacent to each other are arranged parallel to each other while spaced apart by a predetermined interval from each other.

A front retainer is provided in a part of the lid body which faces the substrate storing space when the container main body opening portion is closed. When the container main body opening portion is closed by the lid body, the front retainer is capable of supporting edge portions of the plurality of substrates. In addition, a back side substrate support portion is provided in the wall portion so as to form a pair with the front retainer. The back side substrate support portion is capable of supporting edge portions of the plurality of substrates. When the container main body opening portion is closed by the lid body, since the back side substrate support portion supports the plurality of substrates in cooperation with the front retainer, the back side substrate support portion retains the plurality of substrates in a state where the substrates adjacent to each other are arranged parallel to each other while spaced apart by a predetermined interval from each other.Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2016-186967Patent Document 2: Japanese Patent No. 4584023Patent Document 3: Japanese Patent No. 4030280Patent Document 4: Japanese Patent No. 4150465

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

In the substrate storing container of the related art, it is necessary to place the substrate with respect to the lateral substrate support portion at an accurate position in each of X, Y, and Z directions. The reason is to prevent damages, scratches, or the like to the substrate when the substrate is frequently taken in and out from the substrate storing container by the device in the process of applying various treatments to the substrate to make semiconductor chips. Incidentally, in general, a protrusion is provided in a part of an upper face of the lateral substrate support portion on which the substrate is placed, which is a part in contact with the substrate, the position of the substrate is accurately adjusted by the protrusions, and the protrusion has a shape in which the protrusion is in point contact with or in several millimeter line contact with the substrate at an outer periphery of the substrate so as to minimize the area of contact with the substrate.

The substrate storing container is molded and manufactured by injection molding. Then, in order to form the protrusion described above, it is necessary to engrave the shape of a part corresponding to the protrusion into a part (for molding the lateral substrate support portion) of a mold for molding the substrate storing container. However, in the related art, in a substrate storing container in which the lateral substrate support portion is not integrally molded with the container main body, if it is intended that the lateral substrate support portion is integrally molded with an inner face of the container main body, when the container main body is removed from the mold, the protrusion becomes undercut. For this reason, if integral molding is employed, it is necessary to provide a slide structure in the mold.

If the slide structure is provided in the mold, the operation movement of the mold becomes complicated, and it is necessary to reduce a movement speed so as to prevent damages to the mold. As a result, there occurs a problem such as a prolonged molding cycle or a deterioration in production efficiency. In addition, since the structure of the mold becomes complicated, it becomes difficult to install an optimum cooling circuit, which circulates a coolant in the mold so as to absorb heat of a molten resin, in the mold at an optimum position, and thus there occurs a problem such as an extended cooling time.

An object of the present invention is to provide a method for molding a substrate storing container, a mold, and a substrate storing container with which it is possible to integrally mold a container main body with a lateral substrate support portion without providing a slide structure in the mold.

Means for Solving the Problems

The present invention relates to a method for molding a substrate storing container including a container main body inside which a substrate storing space capable of storing a plurality of substrates is formed, and which has an opening circumferential portion, in which a container main body opening portion is formed to communicate with the substrate storing space, in one end portion, a lid body removably attached to the opening circumferential portion, and capable of closing the container main body opening portion in a positional relationship where the lid body is surrounded by the opening circumferential portion, and lateral substrate support portions provided molded integrally with the container main body so as to form a pair in the substrate storing space, and capable of supporting edge portions of the plurality of substrates in a state where the substrates adjacent to each other among the plurality of substrates are arranged parallel to each other while spaced apart by a predetermined interval from each other when the container main body opening portion is not closed by the lid body, in which the lateral substrate support portion is formed into a plate shape extending in a direction connecting the container main body opening portion of one end portion of the container main body to the other end portion with respect to the one end portion of the container main body, and having an upper face and a lower face, in which an upper face of the lateral substrate support portion has a substrate contact portion in contact with the substrate when supporting the edge portion of the substrate, and in which the substrate contact portion has a bump, a peak portion of the bump is in contact with the substrate when supporting the edge portion of the substrate, and the container main body and the lateral substrate support portion are molded together, the method including a container main body molding step of molding the container main body in a mold space inside a mold having a fixed die and a movable die in a state where a direction perpendicular to a plane passing through the entire periphery of an end edge of the opening circumferential portion of the container main body is inclined in a direction forming a predetermined angle, with respect to a horizontal direction which is a movement direction of the movable die with respect to the fixed die; and a pullout step of pulling the container main body molded in the mold space out from the movable die by moving the movable die so as to retreat from the fixed die.

In addition, the bumps facing the container main body opening portion of one end portion of the container main body and the other end portion of the container main body are preferably formed by one end portion-side inclined face and the other end portion-side inclined face, respectively, which are flat faces. A direction where the other end portion-side inclined face of the bump in the container main body molded in the container main body molding step and present in the mold space is inclined with respect to the horizontal direction as a reference, and a direction where the direction perpendicular to the plane passing through the entire periphery of the end edge of the opening circumferential portion of the container main body in the mold space is inclined with respect to the horizontal direction as a reference are preferably inclined on the same side of the horizontal direction as a boundary line. In addition, the predetermined angle is preferably from 0.1° to 1°.

In addition, the present invention relates to a mold for molding a substrate storing container including a container main body inside which a substrate storing space capable of storing a plurality of substrates is formed, and which has an opening circumferential portion, in which a container main body opening portion is formed to communicate with the substrate storing space, in one end portion, a lid body removably attached to the opening circumferential portion, and capable of closing the container main body opening portion in a positional relationship where the lid body is surrounded by the opening circumferential portion, and lateral substrate support portions provided molded integrally with the container main body so as to form a pair in the substrate storing space, and capable of supporting edge portions of the plurality of substrates in a state where the substrates adjacent to each other among the plurality of substrates are arranged parallel to each other while spaced apart by a predetermined interval from each other when the container main body opening portion is not closed by the lid body, in which the lateral substrate support portion is formed into a plate shape extending in a direction connecting the container main body opening portion of one end portion of the container main body to the other end portion with respect to the one end portion of the container main body, and having an upper face and a lower face, in which an upper face of the lateral substrate support portion has a substrate contact portion in contact with the substrate when supporting the edge portion of the substrate, and in which the substrate contact portion has a bump, a peak portion of the bump is in contact with the substrate when supporting the edge portion of the substrate, and the container main body and the lateral substrate support portion are molded together, the mold including a fixed die; a movable die movable with respect to the fixed die; and a mold space which is formed inside the mold by the fixed die and the movable die, wherein the container main body is molded in a state where a direction perpendicular to a plane passing through the entire periphery of an end edge of the opening circumferential portion of the container main body is inclined in a direction forming a predetermined angle, with respect to a horizontal direction which is a movement direction of the movable die with respect to the fixed die.

In addition, the bumps facing the container main body opening portion of one end portion of the container main body and the other end portion of the container main body are preferably formed by one end portion-side inclined face and the other end portion-side inclined face, respectively, which are flat faces. A direction where the other end portion-side inclined face of the bump in the container main body present in the mold space is inclined with respect to the horizontal direction as a reference, and a direction where the direction perpendicular to the plane passing through the entire periphery of the end edge of the opening circumferential portion of the container main body present in the mold space is inclined with respect to the horizontal direction as a reference are preferably inclined on the same side of the horizontal direction as a boundary line. In addition, the predetermined angle is preferably from 0.1° to 1°.

In addition, the present invention relates to a substrate storing container including a container main body inside which a substrate storing space capable of storing a plurality of substrates is formed, and which has an opening circumferential portion, in which a container main body opening portion is formed to communicate with the substrate storing space, in one end portion; a lid body removably attached to the opening circumferential portion, and capable of closing the container main body opening portion in a positional relationship where the lid body is surrounded by the opening circumferential portion; and lateral substrate support portions provided molded integrally with the container main body so as to form a pair in the substrate storing space, and capable of supporting edge portions of the plurality of substrates in a state where the substrates adjacent to each other among the plurality of substrates are arranged parallel to each other while spaced apart by a predetermined interval from each other when the container main body opening portion is not closed by the lid body, in which the lateral substrate support portion is formed into a plate shape extending in a direction connecting the container main body opening portion of one end portion of the container main body to the other end portion with respect to the one end portion of the container main body, and having an upper face and a lower face, in which an upper face of the lateral substrate support portion has a substrate contact portion in contact with the substrate when supporting the edge portion of the substrate, in which the substrate contact portion has a bump, and a peak portion of the bump is in contact with the substrate when supporting the edge portion of the substrate, and in which the bumps facing the container main body opening portion of one end portion of the container main body and the other end portion of the container main body are formed by one end portion-side inclined face and the other end portion-side inclined face, respectively, which are flat faces.

In addition, a direction where the other end portion-side inclined face of the bump in the container main body is inclined with respect to a movement direction line as a reference which is formed parallel to a horizontal direction which is a direction where a movable die is moved after the container main body has been molded in a mold space inside a mold having a fixed die and the movable die, and a direction perpendicular to a plane passing through the entire periphery of an end edge of the opening circumferential portion of the container main body with respect to the movement direction line as a reference are preferably inclined on the same side of the movement direction line as a boundary line.

In addition, a predetermined angle is preferably formed by the movement direction line, and the direction perpendicular to the plane passing through the entire periphery of the end edge of the opening circumferential portion of the container main body. The predetermined angle is preferably from 0.1° to 1°.

Effects of the Invention

According to the present invention, it is possible to provide the method for molding a substrate storing container, the mold, and the substrate storing container with which it is possible to integrally mold the container main body with the lateral substrate support portion without providing a slide structure in the mold.

