JPH0520333B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a device for transporting or loading thin plate-shaped articles, and in particular to a carrier for storing thin plate-shaped articles such as silicon wafers for manufacturing semiconductor devices in multiple stages. The present invention relates to a device for carrying out or carrying in thin plate-like articles, which is equipped with a take-out arm for carrying out at least one sheet at a time from a carrier, or conversely, carrying it into a carrier.

[Prior Art] It is well known that in the manufacture of semiconductor devices such as LSIs, silicon wafers are supplied to, for example, exposure equipment using carriers in which the wafers are stored in multiple stages with gaps between them. . Belt transport is a common method for taking out wafers one by one from the carrier and sending them to the exposure device, but in order to take out the wafers from the carrier at random with the belt transport method, it is necessary to push the wafers out from behind the carrier. However, with box-type carriers that are not open at the rear, random removal was impossible.

On the other hand, if the wafer is taken out by inserting the take-out arm into the carrier, the wafers can be taken out only from the front of the carrier, so random take-out is possible even with a box-type carrier. The gap between multiple stacks of wafers is generally as narrow as 3/16 inches (approximately 4.8 mm), and the take-out arm must be inserted into this narrow gap. However, since it was not possible to detect the presence or absence of a wafer in the carrier, there was a drawback that the arm would make unnecessary movements.

[Problems to be Solved by the Invention] An object of the present invention is to detect the presence or absence of an object to be transported such as a wafer in a device that inserts an arm into a narrow gap such as a wafer gap in a carrier to carry out and carry out wafers. It is an object of the present invention to provide a device for carrying out or carrying in a thin plate-like article, which can carry out or carry in a thin plate-like article by providing a function so that random carrying-out and carrying-out can be carried out by a box-shaped carrier without unnecessary movement of an arm.

[Means for Solving the Problems] In order to achieve this object, the device for carrying out or carrying in a thin plate-like article of the present invention carries out at least one thin plate-like article one by one from a carrier in which the thin plate-like articles are stored in multiple stages, or and a sensor means for detecting the presence or absence of an article above the article placement surface based on whether or not detection light intersecting the article placement surface of the extraction arm is blocked. In addition, the sensor means includes a reflecting section provided near the tip of the take-out arm, a light emitting section that irradiates the detection light from the base side of the take-out arm toward the reflecting section, and detecting light reflected by the reflecting section. The apparatus is characterized in that it has a light receiving part that receives the detected light on the base side of the take-out arm.

[Function] In this configuration, a sensor means is provided in which a light emitting part and a light receiving part are provided at the base of the takeout arm, and a reflecting part is provided near the tip of the takeout arm, thereby detecting the presence or absence of an article above the article placement surface. This makes it possible to attach the sensor means to the arm itself without increasing the thickness of the portion of the take-out arm to be inserted into the carrier. As a result, the presence or absence of a thin plate-shaped article in the carrier is detected during the carrying-out/unloading operation, thereby eliminating unnecessary movement of the arm and shortening the loading/unloading time.

[Embodiments] Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a side cross section of an embodiment in which multistage storage wafers 2 in a box-shaped wafer carrier 1 are taken out by the take-out arm 5, and FIG. 3 shows a top view of this embodiment as seen from the A-A cross section. A take-out arm 5, which is movable up and down in front of the front opening of the carrier 1, enters from its tip into the gap below a desired wafer 2, and then ascends to place the wafer 2 on its wafer placement surface. The wafer 2 is taken out from the carrier 1 by scooping it up onto the carrier 5a and moving backward. When storing the wafer in the carrier, this operation is reversed. On the right side of the take-out arm 5 in FIGS. 1 and 3, there is an arm drive mechanism (not shown).

Now, the take-out arm 5 is equipped with a light emitter 3 and a light receiver 4 at its base 5b with a space between them vertically, and a reflective surface 7 facing toward the arm base is formed at the tip of the arm. The light from the mounting surface 5
The light passes through an optical path 6 that intersects with the light a, hits a reflective surface 7, is reflected there, and enters the light receiver 4.

In the state shown in FIG. 1, there is nothing on the mounting surface 5a, so the light from the light emitter 3 is reflected by the reflective surface 7 and enters the light receiver 4, and the light receiver 4 detects "no wafer". Outputs the signal.

A state in which the arm 5 has entered the wafer gap in the carrier 1 is shown in FIG. Also that B-B
FIG. 4 is a top view seen from a cross section. In this state, the arm 5 is trying to take out the wafer directly above the gap into which it has entered, and the light from the light emitter 3 is blocked by the wafer and does not reach the reflective surface 7, and therefore enters the light receiver 4. I won't. At this time, the light receiver 4 indicates "wafer present" in response to the interruption of the incident light.
Outputs the signal.

When the "wafer present" signal is issued in the carrier 1, the take-out arm 5 moves upward by a predetermined stroke and scoops up the wafer directly above it.
Next, the wafer is moved backward and pulled out of the carrier with the wafer placed on the mounting surface 5a, and delivered to a transport system into an exposure apparatus or the like.

If a "no wafer" signal is issued within the carrier, the take-out arm is raised beyond the predetermined stroke within the carrier, and the light from the light emitter 3 is blocked by the wafer above. The above-mentioned unloading operation can be performed when the "wafer present" signal is generated, and it can be handled only by movement within the carrier.

Although this embodiment describes a case in which the present invention is applied to a wafer transport system, the present invention is also applicable to the carrying-in/out-loading of thin plate-shaped articles stored in multiple stages at the same pitch in a box having only one opening on one side. It is widely applicable to

[Effects of the Invention] As described above, according to the present invention, it is possible to randomly carry in and out thin plate-shaped articles such as wafers using a box-shaped carrier, and even in the case of so-called multi-stage storage with no gaps, wafers can be There is no need to check the presence or absence of each item outside the carrier, and by moving the take-out arm upward while it is pushed inside the carrier during loading/unloading operations, unnecessary movement is eliminated and the take-out speed is improved. can do.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram conceptually showing an embodiment of the present invention, Fig. 2 is a similar explanatory diagram with the arm advanced into the carrier, and Fig. 3 is a cross-sectional view taken along line A-A in Fig. 1. 4 is a top view seen from the BB cross section in FIG. 2. 1: Carrier, 2: Wafer, 3: Light emitter, 4:
Light receiver, 5: Take-out arm, 5a: Wafer placement surface, 5b: Base, 6: Detection optical path, 7: Reflection surface,
8: Hole.

Claims (1)

[Scope of Claims] 1. A take-out arm for taking out at least one sheet of thin plate-like articles from a carrier in which the sheets are stored in multiple stages, or carrying the articles into the carrier, and an arm that intersects with the article placement surface of the take-out arm. The sensor means detects the presence or absence of an article above the article placement surface based on whether or not the detection light is blocked, and the sensor means includes a reflective section provided near the tip of the take-out arm; It is characterized by having a light emitting part that irradiates the detection light from the base side of the takeout arm toward the reflection part, and a light receiving part that receives the detection light reflected by the reflection part at the base side of the takeout arm. A device for transporting or transporting thin plate-like articles. 2. The device for carrying out or carrying in a thin plate-like article according to claim 1, wherein the detection light from the light emitting section is reflected by the reflecting section after intersecting with the article placement surface.