JPH01285517A - Conveyer device - Google Patents

Abstract

PURPOSE:To suppress a heavy metal from its bad influence to a conveyed material by conveying by a walking beam the conveyed material of semiconductor wafer or the like in a heat treatment part by square motion and constituting the walking beam in its conveyed material adapted part of a ceramic material or the like. CONSTITUTION:In a baking device for a semiconductor wafer 1, a stage 2 is provided being laid in a passage of a conveyed material, that is, the semiconductor wafer 1 so as to enable it to be mounted onto an upper surface. A conveying mechanism, which enables the wafer 1 to be collectively conveyed, uses a walking beam type conveying mechanism, and in a groove 5 formed into a slit shape in a lengthwise direction, a beam 6, constituting at least an upper end, that is, adapted part to the wafer 1 of resin or ceramic material, is provided in a contactless condition with the stage 2. Thus, setting up the metal beam 6 and the wafer 1 in a contactless condition, a heavy metal, springing out from the walking beam heated to a high temperature in a heat treatment part, is suppressed from adhering.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a conveying device.

(Prior Art) Generally, the formation of fine patterns of semiconductor integrated circuits is performed on a semiconductor wafer by a plurality of processes such as resist coating, exposure, and development. In order to perform such multiple processing,
The wafer is transported to each processing section by a conveying means such as a belt or a hand arm, and a heat treatment section, that is, a baking treatment section, is carried out for the purpose of strengthening the adhesion between the wafer and the resist applied to the surface of the wafer. In order to heat the wafer to a high temperature of 100°C or higher, if the belt is used as a means of transporting the wafer in the baking section, the belt will deteriorate due to the heat and the dust generated from the belt will adhere to the wafer. Conventionally, a walking beam type conveyance mechanism in which square motion metal beams are arranged in parallel has been used because of the problem of contamination. Such a walking beam type conveyance mechanism is disclosed in, for example, Japanese Patent Application Laid-Open No. 57-136336,
JP-A-59-55021, JP-A-60-118513
It is disclosed in the publication number etc.

(Problem M to be solved by the invention) However, when such a metal beam is used, the metal beam is heated by the heat of the baking treatment section, and heavy metals such as carbon and sodium contained in the metal are heated. The heat makes it easier to jump out of the metal beam, and the upper part of the metal beam comes into contact with the back surface of the wafer during wafer transport, causing the heavy metals such as carbon and sodium to adhere to the back surface of the wafer. Then, when the wafer is subjected to a diffusion process, the heavy metals seep into the wafer, giving rise to a problem of adversely affecting the pattern formed on the wafer. Therefore, countermeasures against the above problem have been taken by coating the surface of the metal beam with a resin such as Teflon (trade name) or impregnating it with Teflon. The film may peel off due to contact with the wafer during wafer transport, and this peeled Teflon adheres to the wafer and contaminates the wafer, and the metal is exposed at the part where the Teflon is peeled off and comes into contact with the wafer. However, there is a problem in that the heavy metals have an adverse effect on the wafer. In addition to reducing the yield due to contamination of the wafers, there has also been a problem with contamination within the clean room.

The present invention has been made in response to the above-mentioned problems, and it is an object of the present invention to provide a transport device that can prevent heavy metals from adhering to objects to be transported and further prevent contamination of the objects to be transported. .

[Structure of the invention]

(Means for Solving the Problems) The present invention provides an apparatus for transporting an object within a heat treatment section by square motion of a walking beam.
The present invention provides a conveyance device characterized in that at least the portion of the walking beam that contacts the conveyed object is made of resin or ceramic material.

(Function) By constructing at least the above-mentioned object contacting part of the walking beam that transports the transported object in the heat treatment section by square motion with resin or ceramic material,
Preventing heavy metals ejected from the walking beam that has reached a high temperature in the heat treatment section from adhering to the conveyed object,
It is possible to prevent an adverse effect on the conveyed object.

In addition, the conveyed object is not contaminated and can be conveyed cleanly.

(Example) An example in which the apparatus of the present invention is applied to a baking process of semiconductor wafers will be described below with reference to one drawing.

In the semiconductor manufacturing process, after coating a photoresist on the surface of a semiconductor wafer, a pre-bake treatment is performed to evaporate the residual solvent in the coating film and strengthen the adhesion between the coating film and the semiconductor wafer, and photoresist treatment is performed as a pre-treatment. In order to strengthen the adhesion between the resist and the semiconductor wafer, after the photoresist pattern is formed by a device ray bake process or development to remove moisture, the developer and rinse solution remaining in the photoresist film or on the surface are evaporated and the photoresist is removed. A boss baking process is performed to harden the semiconductor wafer and strengthen the adhesion to the semiconductor wafer, and a baking device is used as a device to perform these beta processes.

As shown in FIG. 1, this baking apparatus is installed in a passageway for an object to be transported, such as a semiconductor wafer ω, and is provided with a stage 2 on which the wafer 2 can be placed. This stage (■) is equipped with a vacuum suction mechanism (■) that holds the wafer (■), and a plurality of holes (holes) each having a diameter of (2) connected to the vacuum suction mechanism (■) and opened on the surface of the stage (0) hold the wafer (2). ■It is possible to maintain the following. In addition, this stage (■) is equipped with a heating mechanism (not shown), such as a heater, which heats this stage (■) to a desired temperature.
The structure is such that the wafer ω can be heated by this heat. As shown in Fig. 2, a plurality of such stages (2a) to (2d) are often used in series in order to improve throughput, and each stage (2a) to (2d) is used in series. (2d), when transporting the wafer ■ set near the stage (2a) to the stage (2a), or when transporting the wafer ■ set on the stage (2d) to this stage. (2d) A transport mechanism is provided that enables batch transport of wafers (1) when transporting them to a transport mechanism (not shown) provided nearby and transporting the wafers to a subsequent process. This conveyance mechanism uses an oaking beam type conveyance mechanism, which has slit-like grooves formed in two parallel positions in the series direction, that is, the length direction, of the stages (2a) to (2d). Inside (2), a beam (2) whose at least the upper end, that is, the portion that contacts the wafer ω is made of resin or ceramic material, is provided in a non-contact state with the stage (2). This beam (0
is a metal such as stainless steel (as shown in Figure 3).
A resin member (■) or a ceramic member (SO3) is protruded from the upper end of the beam (e), so that the metal beam (0) and the wafer (2) are not in contact with each other. The wafer (2) placed on the stage (2) can be raised and lowered, and the wafer (2) can be transported by horizontally sliding the stage (2) of the beam (2).This is shown in Figure 4. As shown in the figure above, the stage has a column ■ that supports both ends of the beam 0 that protrudes horizontally from the side, and a slope ■ that is installed at the bottom end of this column and whose lower surface is inclined upward in the direction of movement. The slider (10) has a structure that moves up and down while sliding on a roller (11) that is in contact with the lower surface. Support with length (1
2) Rotatably attached to both ends. This support (1
2) is attached with a drive mechanism such as an air cylinder (13), and the slider (10) slides on the roller (10) which is pivotally attached to the support (12) due to the drive of this air cylinder. , is configured to move the beam (2) up and down.

In addition, there is a screw thread (14) at one end of the lower surface of this support (12).
A leg body (15) is provided with a protrusion formed thereon, and this screw thread (
By rotationally driving the screw drive shaft (16) fitted into the beam 0, the support body (1
2) is provided so as to be movable in its length direction. The drive shaft (16) is linked to a pulse motor (17), and the rotation of the pulse motor (17) allows the beam (1) and the support (12) to move. In order to ensure smooth movement of the beam (1) and the support (12), legs (18) protruding from the back surface of the support (12) are arranged in the same direction as the drive shaft (16). It is inserted into the provided guide shaft (19). The baking device is configured in this way.

Next, the moving body of this baking device will be explained.

First, set the desired baking temperature, heat the stages (2a) to (2d) in advance, and then
is transferred and set near the stage (2a) by another transfer means. Then, the square motion, that is, the support (
A roller (10) that drives an air cylinder (13) provided in the roller (12) and is pivotally attached to the support (12).
While the slider (10) slides, the two beams 0 are raised. As the beam 0 rises, the wafer (2) is raised, and the pulse motor (17) is rotated, and the drive shaft (16) linked to this moves the beam (0 and the support (12)) to the length of the beam 0. After this beam 0 has moved a predetermined distance, the beam 0 is lowered by the operation of the air cylinder (13).

The wafer (2) is placed at a predetermined position on the stage (2a). The placed wafer (2) is then suctioned and held by a vacuum suction mechanism (2) connected to a hole formed on the surface of the stage (2a). here.

Baking the wafer ω for a predetermined time at the temperature set above,
The water on the surface of the wafer ω is removed, the acid is removed, the solvent is removed, etc., and the baking process is carried out in the same way (stage 2).
Repeat steps a) to (2d).

As described above, the stage (2), which is a heat treatment section, is set at a high temperature in order to bake the wafer (2). Therefore, a walking beam type transport mechanism that uses square motion is used to transport the wafer (2) in this heat treatment section.However, since it is natural that this beam (0) is composed only of metal, when transporting the wafer (2), it is necessary to use the above-mentioned metals. The beam 0 of the wafer ω comes into contact with the back surface of the wafer ω. Then, the beam (0) becomes high temperature due to the radiant heat of the stage (2), and heavy metals such as carbon and sodium in this metal tend to fly out, and the carbon and sodium that fly out adhere to the wafer (2). During the diffusion process of the wafer ω, there was a problem that the wafer ω seeped into the interior of the wafer ω, adversely affecting the wafer ω and lowering the yield.Therefore, a resin material such as Teflon (trade name) or a ceramic member was attached to the upper end of the beam ω. By setting the metal beam 0 and the wafer ω in a non-contact manner, the adhesion of heavy metals is suppressed.The surface of the beam 0 is coated or impregnated with the same material as the resin member (■). Similarly, heavy metals can be prevented from adhering to heavy metals, but simply forming a thin film such as the coating described above may peel off when the beam ■ and wafer ■ come into contact, contaminating the wafer ■ or inside the clean room, or expose the exposed area at the peeled part. Since there was a problem that heavy metals could adhere to the wafer (■) due to contact between the metal and the wafer (■), a resin member (■) was installed protruding from the upper end of the beam (■) to prevent the above problem.This resin member (■) As shown in FIGS. 3 and 5, even if the beam (2) is made of a resin member (2) or a ceramic member with at least the wafer ω contact surface formed in a circular shape, Even if resin members or ceramic members having a shape that partially protrudes upward at some intervals are provided as shown in FIG. 7A, FIG. 7B, and FIG.
As shown in the figure, at least a wafer inserted into the beam 2 at a predetermined interval 2) A resin member 2 whose abutting surface is formed into a spherical shape, or even a ceramic member 2, is circular as shown in Figs. 9A and 9B. Even if a plurality of columnar resin members (2) are inserted, the same effect can be obtained. In this case, the resin member ■ and the wafer ω
The contact part with the one in Figures 3 and 5 is a line contact, and the one in Figure 6 is a line contact.
The one in FIG. 9 and FIG. 9 is a line contact close to a point, and FIG.

Since the one in FIG. 8 is a point contact, the point contact in FIGS. 7 and 8 is more preferable in consideration of the clean transfer of the wafer (1).

Further, by applying a resin or ceramic coating to the exposed surface of the metal beam (2) and protruding a resin or ceramic member from the upper end thereof, it is possible to more reliably prevent the heavy metal from flying out.

In the above embodiment, at least the part of the beam (2) in contact with the conveyed object is made of resin or ceramic, and a resin or ceramic member is provided at the upper end of the metal beam. A similar effect can be obtained.

As described above, according to this embodiment, at least the above-mentioned corrugated body contacting part of the walking beam that conveys the conveyed object in the heat treatment section by square motion is made of resin or ceramic material, thereby achieving the above-mentioned It is possible to prevent heavy metals ejected from the walking beam heated to a high temperature in the heat treatment section from adhering to the object to be transported, thereby preventing an adverse effect on the object to be transported, thereby improving yield.

Further, the conveyed object is not contaminated, enabling clean conveyance, and furthermore, contamination of the environment such as a clean room can be prevented.

〔Effect of the invention〕

As explained above, according to the present invention, at least the object-contacting portion of the walking beam that transports the object in the heat treatment section by square motion is made of resin or ceramic material. It is possible to prevent the harmful effects of heavy metals that fly out on objects to be transported, and to improve yield. Further, the object to be transported is not contaminated, and the effect of enabling clean transport can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a baking device for explaining one embodiment of the present invention, FIG. 2 is a diagram showing the structure of FIG. This figure is an explanatory diagram of another embodiment of the beam shown in FIG. 1. 1... Wafer 2... Stage 6... Beam 7... Resin member patent applicant Tokyo Electron Ltd. Chill Kyushu Ltd. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 A Fig. 6 B Fig. 7 A Fig. 7 B Fig. 8 Fig. 9 Fig. A Fig. 9 B

Claims (1)

[Claims] What is claimed is: 1. A device for transporting an object within a heat treatment section by the square motion of a walking beam, wherein at least a portion of the walking beam that contacts the object is made of a resin or a ceramic material.