JP2565249B2 - Linear transport means - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a linear conveying means for carrying an object to be conveyed on a plurality of lines. INDUSTRIAL APPLICABILITY The linear transfer means of the present invention can be used to transfer a wafer, for example, in the field of semiconductors.

[Outline of Invention]

The present invention relates to a linear conveying means for carrying an object to be conveyed on a plurality of lines, or a linear means for carrying an object to be conveyed on a plurality of lines and at the same time performing a heat treatment on the object to be conveyed. In the conveying means, the wire is provided with a spherical protrusion of the same material as the wire, and the object to be conveyed is placed on the spherical protrusion,
By carrying out point-to-point transportation, the object to be transported and the above-mentioned transportation line are brought into contact with each other on the above-mentioned protrusions, so that the generation of dust or the occurrence of scratches when the contact portion is large is prevented. The size of the object is small, and therefore the object to be transferred is not adversely affected.

[Conventional technology]

2. Description of the Related Art Conventionally, linear conveying means for carrying an object to be conveyed by placing it on a plurality of lines has been used in various fields. For example, Japanese Patent Application Laid-Open No. 58-40828 discloses a mechanism in which a semiconductor wafer is conveyed by a wire conveyor to perform plasma reaction processing.

When a linear conveying means is used, generally, for example, as shown in FIG.
An object to be transferred 2 such as a wafer is placed on and the desired transfer is performed by moving the lines 1 and 1. However, in this case, the lines 1 and 1 and the transported object 2 are in line contact with each other at least with respect to the respective lines 1 and 1, and dust may be generated due to rubbing or the transported object 2 may be damaged.

In the case of IC and other semiconductor wafers, it may be necessary to heat-treat the back surface (the surface opposite to the pattern-formed surface). However, if the above-mentioned transportation means is used at this time, heat treatment is generally performed efficiently. Heat treatment is performed with the back surface of the wafer as the top surface (upper surface in FIG. 5). However, in this case, the pattern forming surface becomes the lower surface, and the pattern forming surface 2a comes into contact with the linear transfer lines 1, 1 as shown in FIG. If so, the pattern surface 2a is likely to come into contact with the wires 1, 1 such as wires, and dust adhesion due to wire rubbing or scratches on the pattern surface easily occur, which greatly affects reliability such as occurrence of pattern defects, and the above problem is more important. Becomes That is, stainless steel or the like is often used for the wires 1 and 1 for transportation, but this is apt to oxidize and roughen the surface, especially at high temperatures (such as when heat-treated while transporting), and the surface is voluminous. However, the roughened state tends to damage the transported object, and the oxide tends to be peeled off to become dust. In the case of line contact as shown in FIG. 5, the dust is the surface of the transported object 2. Will be directly attached to.

On the other hand, in Japanese Utility Model Application Laid-Open No. 60-81907 and the specification related to the publication, a plurality of chip-shaped pipe materials made of a separate non-contaminating material are attached to a flexible belt core material for transportation. A transfer means for transferring a wafer or the like configured to perform is described. However, also in this prior art, since the material to be conveyed is conveyed by the pipe material, the material to be conveyed and the tip pipe material always come into line contact in the length of each tip pipe material. Therefore, although it is considered that the contact length is smaller than the contact with the belt core material itself, in the end, the total length of the line contact length between each chip-shaped pipe material and the transported material is equal to that of the transported material. The tip pipe material comes into line contact, and the above-mentioned problems associated with line contact are still unsolved. Even if the outer peripheral angle of the cylindrical pipe material (the edge portion of the end face of the cylinder) is curved, the degree of line contact does not differ greatly, and this does not solve the problem. Originally, this conventional technology was used for semiconductor wafers, etc.
"Transfer between various treatment steps such as chemical treatment, heat treatment, cleaning treatment", that is, "when moving a semiconductor wafer from a pre-process to a post-process, from a carrier or boat of the pre-process to a boat suitable for the post-process or It is assumed that `` the semiconductor wafer is transferred to the carrier '', and it is not assumed that the material to be conveyed is heated at the same time as the conveyance by using a stainless wire or the like. This is considered to be a technology that only envisions transport that is sufficient to prevent contamination, and this is supported by the fact that only belt materials are envisioned.

[Technical problems to be solved by the invention]

As described above, in the general linear conveying means, there is a problem that dust is generated due to rubbing or scratches due to contact between the conveyed object and the conveying line. This becomes a serious problem especially when the object to be transported is an electronic material such as a semiconductor wafer or other members requiring precision.

SUMMARY OF THE INVENTION It is an object of the present invention to solve this problem and to provide a linear conveying means in which an object to be conveyed is not easily scratched and dust is less likely to occur.

[Means for solving problems]

In order to solve the above-mentioned problems, the linear conveying means of the present invention has a configuration in which an object to be conveyed is placed on a plurality of lines for conveying, and a spherical protrusion is provided on the line, and the spherical protrusion is formed on the spherical protrusion. An object to be conveyed is placed, and the object is conveyed by making point contact with each other, and the plurality of lines and the spherical protrusion are made of the same material.

In addition, in order to solve the above-mentioned problems, the linear transporting means of another invention is configured such that the transported object is placed on a plurality of lines and transported, and at the same time, the thermal processing is performed on the transported object.
A spherical projection is provided on the line, the object to be transported is placed on the spherical projection, and the point-contact is performed to carry the article, and the plurality of lines and the spherical projection are made of the same material.

The structure of the present invention will be described below with reference to FIG. 1 showing an embodiment of the present invention which will be described later in detail. That is, in the present invention, a plurality of (two in the figure) lines
Spherical protrusions 3, 3 are provided on 1, 1, and an object to be conveyed 2 is placed on the spherical protrusions 3, 3 and point-contacted for conveyance. Multiple lines 1,
1 and the spherical protrusions 3, 3 are made of the same material.

In this embodiment, the object to be transferred 2 is transferred, and at the same time, the object to be transferred 2 is heat-treated.

[Action]

According to the present invention, as a result of the above configuration, the object to be conveyed 2 and the line 1 are conveyed while being in point contact with each other at the protrusion 3. Therefore, the contact area between the object to be conveyed 2 and the conveying wire 1 is smaller than that in the conventional case, and dust is generated due to rubbing.
Damage to the transported object is suppressed. When carrying out the heat treatment on the carried object 2 at the same time as carrying the carried object 2, there is no dust generation and no damage to the carried object, which is extremely advantageous. Since the wire 1 and the protrusion 3 are made of the same material,
It is advantageous in that it is easy to form.

〔Example〕

Examples of the invention will be described below. This example is
The present invention is applied to the transportation of semiconductor wafers (particularly IC wafers).

In this embodiment, as shown in FIG. 1, ball-shaped portions are formed on the carrying lines 2, 2 to form the projections 3, 3. In this example, specifically, stainless wire was used as the wires 1, 1 for transportation, and stainless balls were attached to the wire. This can be obtained, for example, by using a stainless wire (or a Teflon-processed one), forming a hole corresponding to the wire in a stainless ball, and passing the wire through the hole and caulking them to be integrated.

Of course, the wire material is not limited to stainless steel, and other materials may be used. For example, if a quartz wire or the like is used, it is effective in terms of scratches and dust, and in this case, the protrusions are also formed of quartz balls. This protrusion is also effective in terms of scratches and dust, which is extremely advantageous.

According to the present embodiment, since the spherical protrusion 3 is formed on the line 1, the semiconductor wafer, which is the object to be conveyed 2, comes into point contact with the protrusion 3 and the contact portion is extremely small, and therefore scratched. The generation of dust and the generation of dust are extremely small. Even if the surface of the stainless ball is oxidized, scratches and dust are significantly reduced. In the case of high-temperature heat treatment, there are cases where the surface of a wire or the like for transportation cannot be subjected to treatment such as Teflon processing, but even in this case, the present invention can be advantageously applied.

This embodiment is used when the back surface of the semiconductor wafer, which is the object to be transferred 2, is heat-treated, and the pattern forming surface 2a comes into contact with the transfer lines 1 and 1. In this case as well, the defect rate is high. Is extremely small, and the product yield is improved. That is,
By using a stainless steel ball-carrying wire as the wafer carrying wire as in this example, only the protrusion 3 (ball tip) is point-contacted, which is what was conventionally line-contacted to the wafer surface. There are no scratches,
The number of dust is 900 by the conventional Sunteres wire
While it was FOB / 1 [mu] ^□, 10 or less in the present embodiment
It was suppressed to / 1μ ^□ . Further, the carrying means of the present example can be obtained easily and inexpensively because it is sufficient to attach a stainless wire ball.

In order to efficiently heat-treat the back surface of the semiconductor wafer without adversely affecting the pattern formation surface using the transporting means of this example, the following steps were adopted in this example.

As shown in FIG. 3, a stainless wire having a diameter of 1 mm is used as a wire 1 for transportation, and a stainless ball having a diameter of 3.5 mm is attached to the wire 1 to form a protrusion 3, and the wire is used as shown in FIG. As shown in the bottom view), the wafer to be transferred 2 is placed on the four protrusions 3. Here, the pattern forming surface 2 a of the wafer is in contact with the protrusion 3. The wafer notch 26 was aligned with the transfer direction. This is first preheated in a low temperature furnace 41 (about 330 ° C.) shown in FIG. 2 (b).
Next, it heats in the high temperature furnace 42 (about 440 degreeC). This allows
The back surface of the wafer, which is the transported object 2, is heat-treated. This process is a heat treatment performed after metallization to obtain an ohmic contact on the back surface of the wafer, and is a process called flash alloy. This example uses the present invention for this processing, and is an application for reducing the influence on the pattern forming surface 2a where the transfer line 2 comes to the crocodile.

After heating in the high temperature furnace 42, it is cooled in the cooling unit 43. Cooling was natural cooling here, and was cooled to about 100 ° C. The movement of the wafer is as shown in FIG. 2 (c), and each furnace 41, 42 is formed with a groove 5 for receiving the wire which is the line 1 for transportation as shown in FIG. The wafer is conveyed by the movement as indicated by the broken line 61 in FIG. 2), the wire is set in the groove 5 of the low temperature furnace 41 at the broken line 62, and the low temperature heating is performed.
The wire rises at 63, is conveyed at the broken line 64, and is similarly treated at the high temperature furnace 42 as indicated by the broken lines 65 and 66. Then, it is conveyed by the broken line 67, cooled by the movements shown by the broken lines 68, 69, and conveyed by the broken line 70 to enter the subsequent process.

In this embodiment, as described above, the dust adhesion is 900 /
mu ^□ degree fell to 10 / mu ^□ or less, no damage of the wafer, highly reliable semiconductor device is obtained, in which conventional problems were resolved.

The present invention is not limited to the above-described embodiments, and for example, the object to be conveyed may have a configuration of abutting on the protrusion and the other line portion, and can be implemented in various other modes.

〔The invention's effect〕

As described above, according to the present invention, there is an effect that the transported object is less likely to be scratched and dust is less generated.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 1 (a) is a side view, and FIG. 1 (b) is a B ₁ direction arrow view in FIG. ₁ (a). FIG. 2 is a transfer process diagram of the embodiment, FIG. 3 is a configuration diagram of a transfer line, and FIG. 4 is a perspective view of the furnace. FIG. 5 shows a conventional example, FIG. 5 (a) is a side view, and FIG. 5 (b) is a view in the direction of arrow B in (a). 1 ... Transport line (wire), 2 ... Transported object (semiconductor wafer), 2a ... Pattern forming surface, 3 ... Projection part.

Claims (5)

(57) [Claims] 1. A linear carrying means for carrying an object to be conveyed on a plurality of lines, wherein a spherical projection is provided on the line, and the object to be conveyed is placed on the spherical projection and point-contacted. A linear transporting means for transporting, wherein the plurality of lines and the spherical protrusion are made of the same material. 2. The linear conveying means according to claim 1, wherein the plurality of wires and the spherical protrusions are made of a material selected from stainless steel and quartz. 3. A linear conveying means for carrying an object to be conveyed on a plurality of lines and carrying out the heat treatment at the same time, wherein a spherical projection is provided on the line, and the spherical projection is provided. A linear conveying means, characterized in that the object to be conveyed is placed on the upper surface and is conveyed in point contact, and the plurality of lines and the spherical protrusions are made of the same material. 4. The linear conveying means according to claim 3, wherein the linear conveying means performs linear conveyance. 5. The linear conveying means according to claim 3, wherein the plurality of lines and the spherical protrusions are made of a material selected from stainless steel and quartz.