JP2009059930A - Open cassette load port - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve mapping precision of a mapping sensor and to cause no shift in fitting position of the mapping sensor by letting an operator not touch the mapping sensor. <P>SOLUTION: In an open cassette load port having a load port plate provided with an opening portion where an open cassette containing a substrate including a semiconductor wafer is taken in and out, a tilting door disposed on the front side of the load port plate and provided rotatably to fall to this side of the load port plate, an open cassette mount base provided to the tilting door and mounted with the open cassette taken in and out of the opening portion, and a back door disposed on the rear side of the load port plate and provided slidably to open and close the opening portion, the mapping sensor which detects the position of the semiconductor wafer is provided to move forward and backward between the back door and the tilting door. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mapping mechanism for mapping a substrate, such as a semiconductor wafer, installed in a clean room and transported in the clean room in a manufacturing process for semiconductors, electronic component-related products, optical disks, etc., before being transferred to a processing apparatus. Is related to the open cassette load port equipped with.

  A conventional open cassette load port is described, for example, in JP-A-11-145244 (Patent Document 1).

  Conventionally, in a semiconductor manufacturing apparatus or inspection apparatus, the following operations have been performed as a work before transporting a substrate to be processed.

  First, an operator transports an open cassette (hereinafter referred to as a cassette) on which a substrate (semiconductor wafer or the like) is loaded, and places it on a loading port mounting table.

  Next, the rear door of the cassette is lowered by driving the motor. At this time, the mapping sensor attached to the upper part of the rear door is lowered by the motor drive simultaneously with the rear door to perform mapping. After the lowering of the rear door and completion of mapping, the substrate is pulled out from the cassette by the robot, and the substrate (semiconductor wafer or the like) is carried into a substrate processing apparatus, for example, a substrate inspection apparatus.

  In the mapping structure, a projector (transmitter sensor) and a receiver (receiver sensor) of a reflection type sensor are attached to the upper part of the rear door, and the presence or absence of the wafer is detected by receiving the reflected light of the wafer.

  However, since the sensor is attached to the upper part of the rear door, the distance to the wafer is increased, which may reduce the mapping accuracy. In addition, when the reflection type sensor is used, the tilt state of the mounted wafer is slightly different, so that the amount of reflected light received by the wafer varies and the mapping accuracy may decrease.

  Furthermore, when the open cassette load port side is viewed from the rear side, that is, the substrate processing apparatus, for example, the substrate inspection apparatus, the mapping sensor is exposed, so that the operator touches the mapping sensor when checking the operation during maintenance. As a result, there is a possibility that the mounting position of the mapping sensor will be out of order.

Japanese Patent Laid-Open No. 11-145244

  In view of the above problems, an object of the present invention is to provide an open cassette load port with good mapping accuracy.

  The present invention includes a load port plate provided with an opening through which an open cassette for storing a substrate including a semiconductor wafer is inserted and removed, and is positioned on the front side of the load port plate so as to roll to the front side of the load port plate. A tilting door provided movably, an open cassette mounting base for placing an open cassette that enters and exits the opening, and a back surface of the load port plate so as to open and close the opening. In an open cassette load port having a rear door provided slidably, a mapping sensor for detecting the position of the semiconductor wafer is provided so as to go back and forth between the rear door and the tilt door.

  In the present invention, since the mapping sensor is provided so as to go back and forth between the rear door and the tilt door, the distance between the substrate (semiconductor wafer, etc.) and the mapping sensor is shorter than that of the conventional example, and the accuracy of mapping is improved. In addition, an open cassette load port with good mapping accuracy can be provided.

  Embodiments of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1, 3, and 4, the open cassette load port includes a load port plate 301 provided with an opening 601 into which an open cassette 101 for storing a semiconductor wafer is inserted and removed, and a load port plate 301. It has a tilting door 103 that is located on the front side and is pivotably provided so as to roll to the near side of the load port plate 301.

  Further, the open cassette load port is provided on the tilting door 103 and is located on the back surface of the load cassette plate 102 on which the open cassette 101 for entering and exiting the opening 601 is placed, and opens and closes the opening 601. The rear door 104 is slidably provided.

  Furthermore, the open cassette load port includes a pulley 302 disposed vertically on the back surface of the load port plate 301 with an opening 601 therebetween, and a steel belt 303 that is hung on the upper and lower pulleys 302 and to which the rear door 104 is attached. And a mapping sensor 304 that detects the position of the semiconductor wafer that is attached to the belt 303 and is provided so as to go back and forth between the back door 104 and the tilt door 103.

  Since the mapping sensor 304 and the rear door 104 attached to the belt 303 are provided at positions facing each other with the upper and lower pulleys 302 therebetween, they move up and down in opposite directions. When the rear door 104 is lowered, the mapping sensor 304 is raised.

  The mapping sensor 304 detects the position of the semiconductor wafer 501 in the open cassette 101 when moving up and down. Since the plurality of semiconductor wafers 501 are arranged so as to overlap in the vertical direction, the position of the semiconductor wafer 501 is detected by the vertical movement of the mapping sensor 304.

  That is, the direction in which the mapping sensor 304 travels is in a relationship that follows a direction in which a plurality of semiconductor wafers 501 (substrates) are arranged in parallel.

  For this reason, when a plurality of semiconductor wafers are placed side by side, the mapping sensor is changed to the lateral movement method in order to detect the position of the semiconductor wafer. The back door is also moved laterally.

  As shown in FIG. 5, the mapping sensor 304 includes a transmission sensor 304 and a reception sensor 304 as a set. The transmission sensor 304 and the reception sensor 304 that penetrate the opening 601 of the load port plate 301 and the front end faces the open cassette 101 are positioned so as to sandwich the edge side of the semiconductor wafer 501.

  A signal emitted from the transmission sensor 304 (optical signal) is received by the reception sensor 304 unless blocked by the edge side of the semiconductor wafer 501 and is not received when blocked. The position of the semiconductor wafer 501 is detected by this reception / non-reception.

  The mapping sensor 304 is a passage detection type that detects whether a signal has passed or not passed. A reflection detection type may be used instead of the mapping sensor. The reflection detection type has a configuration in which a signal emitted from a transmission sensor is reflected by a semiconductor wafer and received by a reception sensor.

  When the rear door 104 shown in FIG. 4 closes the opening 601, the mapping sensor 304 is positioned so as to be sandwiched between the rear door 104 and the tilt door 103. At this time, as shown in FIG. 6, the mapping sensor 304 is positioned so as to enter the notch recess 602 formed at the lower end of the opening 601.

  Next, the operation of the open cassette load port with automatic tilt will be described.

  FIG. 1 shows a loaded state of an open cassette 101 (hereinafter referred to as a cassette). In the semiconductor wafer loading cassette 101 that has been transported in the clean room, the semiconductor wafer is placed in a vertical posture on an open cassette mounting table 102 (hereinafter referred to as a cassette mounting table).

  Thereafter, as shown in FIG. 2, the tilting door 103 tilts in order from 201 to 202, 203, 204, 205. As a result, the semiconductor wafer 501 shifts to a horizontal posture, and the back door 104 opens to enter a wafer transfer standby state. Thereafter, the semiconductor wafers 501 are transferred one by one to a semiconductor manufacturing apparatus or semiconductor inspection apparatus which is a higher-level apparatus.

  The semiconductor wafer that has been processed by the host device is returned to the original position of the cassette 101. Then, the back door 104 is closed, and the semiconductor wafer loading cassette 101 tilts in order from 205 to 204, 203, 202, 201, shifts to a vertical posture, and enters a take-out standby state. And it is conveyed to another processing apparatus.

  In the above operation, it is necessary to perform wafer mapping before the semiconductor wafer 501 is transferred to the host device. The purpose of the mapping is that there is no mounting leakage of the semiconductor wafer 501 in each stage of the cassette 101 loaded with semiconductor wafers, two semiconductor wafers 501 are not stacked in one stage, or straddle over different stages. It is to detect whether it is not placed diagonally.

  Performing mapping is a very important function because it prevents empty transport when the robot transports the semiconductor wafer 501 and breaks the semiconductor wafer due to contact between the robot hand and the semiconductor wafer 501.

  As described above, the mapping sensor 304 detects whether the semiconductor wafer 501 is mounted properly. Mapping in this inspection is performed with high accuracy.

  That is, since the mapping sensor 304 for detecting the position of the semiconductor wafer 501 is provided so as to go back and forth between the back door 104 and the tilt door 103, the distance between the semiconductor wafer 501 and the mapping sensor 304 is larger than that of the conventional example. Nearly, the mapping accuracy is good. For this reason, an open cassette load port with good mapping accuracy can be provided.

  Next, the operation during mapping will be described in more detail.

  After the tilting door 103 is closed, the back door 104 is opened by shortening the rod of an open / close air cylinder (not shown) of the back door 104. At this time, when the rear door 104 is lowered, the steel belt 303 attached and fixed thereto is rotated by the pulley 302, and the mapping sensor 304 is raised to perform sensing.

  Then, the input signal is transmitted to a host device (semiconductor manufacturing apparatus, semiconductor inspection apparatus, etc.). Thereafter, when moving to the rod shortening reaching point of the open / close air cylinder, the rear door 104 stops and the mapping sensor 304 also stops simultaneously. The mapping is completed when the mapping sensor 304 is stopped.

  That is, the mapping operation and the rear door 104 opening operation are performed simultaneously. Mapping is performed by the mapping sensor 304 composed of the transmission sensor 304 and the reception sensor 304 as shown in a plan sectional view at the time of mapping (FIG. 5).

  Next, the closing operation of the rear door 104 will be described.

  The semiconductor wafer that has been processed by the host device is returned to the original position of the cassette 101. When the collection of all the semiconductor wafers is completed, the back door 104 is lifted by the rod extension of the open / close air cylinder of the back door 104, and the closing operation is performed.

  At this time, the steel belt 303 attached and fixed to the rear door 104 is rotated by the pulley 302, and the mapping sensor 304 is lowered. However, when the rear door 104 is closed, since the processing is completed in the host device, a sensing signal is not transmitted to the host device.

  When the opening / closing air cylinder moves to the rod extension reaching point, the rear door 104 stops and the mapping sensor 304 also stops simultaneously. This state is shown in FIG. Then, the tilting door 103 is opened, and the cassette 101 loaded with semiconductor wafers is in a standby state for taking out, that is, the state shown in FIG.

  In the state shown in FIG. 4, the rear door 104 is in a closed state, and the mapping sensor 304 is stored in a recess 602 provided in the lower part of the load port plate 301 as shown in FIG. 6. FIG. 6 is a view of FIG.

  Since the mapping sensor 304 contained in the recess 602 is positioned so as to be sandwiched between the rear door 104 and the tilt door 103, the mapping sensor 304 is isolated from the work area.

  For this reason, the operator is prevented from touching the mapping sensor at the time of confirming the operation during maintenance, and the mounting position of the mapping sensor does not get out of order.

FIG. 4 is a perspective view of the entire open cassette load port according to the embodiment of the present invention as viewed from the front side. FIG. 10 is a perspective view illustrating the operation of the tilting door of the open cassette load port in five operation modes according to the embodiment of the present invention. It is a side view which concerns on the Example of this invention and shows arrangement | positioning of the mapping mechanism containing a mapping sensor. This side view shows the open state of the rear door. It is a side view which concerns on the Example of this invention and shows arrangement | positioning of the mapping mechanism containing a mapping sensor. This side view shows a waiting state for mapping. FIG. 5 is a plan sectional view of the open cassette load port according to the embodiment of the present invention, which is sectioned along the plane direction. This plan sectional view shows the arrangement of the mapping mechanism. It is a side view which concerns on the Example of this invention and shows the storage position of a mapping sensor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Open cassette, 102 ... Open cassette mounting base, 103 ... Tilting door, 104 ... Back door, 301 ... Load port plate, 302 ... Pulley, 303 ... Steel belt, 304 ... Mapping sensor, 501 ... Wafer, 601 ... Opening, 602... Recess.

Claims (8)

A load port plate provided with an opening for receiving and inserting an open cassette for storing a substrate including a semiconductor wafer, and positioned on the front side of the load port plate so as to be able to turn to the front side of the load port plate. A tilt door provided, an open cassette mounting base on which the open cassette for entering and exiting the opening is placed, and a rear surface of the load port plate, which opens and closes the opening. In an open cassette load port having a rear door slidably provided in
An open cassette load port, wherein the mapping sensor for detecting the position of the semiconductor wafer is provided so as to go back and forth between the rear door and the tilt door. A load port plate provided with an opening for receiving and inserting an open cassette for storing a substrate including a semiconductor wafer, and positioned on the front side of the load port plate so as to be able to turn to the front side of the load port plate. A tilt door provided, an open cassette mounting base on which the open cassette for entering and exiting the opening is placed, and a rear surface of the load port plate, which opens and closes the opening. In an open cassette load port having a rear door slidably provided in
A pulley disposed vertically on the back surface of the load port plate, and a belt that is hung on the upper and lower pulleys and to which the back door is attached;
An open cassette load port having a mapping sensor for detecting a position of the semiconductor wafer attached to the belt and provided so as to go back and forth between a back door and a tilt door. In the open cassette load port according to claim 1 or 2,
The open cassette load port, wherein the mapping sensor moves back and forth as the rear door slides. In the open cassette load port according to claim 1 or 2,
The open cassette load port, wherein the mapping sensor linked to the operation of the back door moves in a direction opposite to the back door. The open cassette load port according to claim 4,
The mapping sensor is located at an upper position when the rear door opens the opening, and conversely, is located at a lower position when the rear door closes the opening. Open cassette load port. In the open cassette load port according to claim 1 or 2,
The mapping sensor includes a transmission sensor and a reception sensor as a set, and a reflection detection type in which a transmission signal from the transmission sensor is reflected by the substrate and received by the reception sensor, and a transmission signal from the transmission sensor. An open cassette load port including a passage detection type that is received by a receiving sensor when not blocked by the substrate. In the open cassette load port according to claim 1 or 2,
An open cassette load port, wherein a direction in which the mapping sensor travels is along a direction in which the plurality of substrates are arranged in parallel. In the open cassette load port according to claim 1 or 2,
An open cassette load port, wherein the mapping sensor is positioned between the rear door and the tilt door when the rear door closes the opening.

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