KR20070013038A - Wafer cassette stage for semiconductor memory manufacturing and wafer flat-zone alignment testing method used the same - Google Patents

Abstract

A wafer cassette stage for a semiconductor device and a method for inspecting a wafer flat-zone alignment using the same are provided to reduce a manufacturing time of the semiconductor device by instantly detecting an alignment state of the flat-zone of the wafer, when the wafer cassette is mounted on the wafer stage. A wafer cassette stage for a semiconductor device includes a stage body(200) and a sensor(400). A wafer cassette is mounted on the stage body. Plural wafers are stacked on the wafer cassette. The sensor is normally spaced apart from a flat-zone of the wafer by a predetermined direction. The sensor is arranged on the stage body. The sensor is selected from the group consisting of an optical sensor, an IR(InfraRed) sensor, and a distance measuring sensor. A wafer cassette transfer unit is spaced apart from the stage body by a predetermined distance. The wafer cassette transfer unit picks up the wafer cassette and delivers the wafer cassette to a predetermined position.

Description

Wafer Cassette Stage for Semiconductor Device Manufacturing and Wafer Flat Zone Alignment Inspection Method Using the Same [Wafer Cassette Stage for SEMICONDUCTOR MEMORY MANUFACTURING AND WAFER FLAT-ZONE ALIGNMENT TESTING METHOD USED THE SAME}

1 is a perspective view showing a wafer cassette stage for manufacturing a semiconductor device of the present invention.

2 and 3 are plan views illustrating mounting positions of sensors detecting the wafer flat zone shown in FIG. 1.

4 is a block diagram illustrating the operation of the sensors and the controller shown in FIG. 1.

5 is a flowchart showing a wafer flat zone alignment inspection method of the present invention.

** Explanation of Signs of Major Parts of Drawings **

200: stage body

210: seating part

220: support

300: Wafer Cassette

400: sensors

500: control unit

The present invention relates to a wafer cassette stage for manufacturing a semiconductor device and a wafer flat zone alignment inspection method using the same, and more particularly, to a wafer cassette stage for manufacturing a semiconductor device for detecting whether the flat zone of wafers loaded in the wafer cassette is normally aligned and the same. It relates to a wafer flat zone alignment inspection method used.

In general, in order to manufacture a semiconductor device, various processes such as diffusion, exposure, etching, cleaning, and the like are sequentially or selectively performed.

The etching process is a process of forming a semiconductor integrated circuit on the upper surface of the wafer, and is a process of processing the lower layer using the photoresist pattern formed by the exposure process as a mask.

In general, an etching apparatus for manufacturing a semiconductor device performing the etching process includes a wafer cassette stage on which a wafer cassette on which a plurality of wafers are loaded is mounted, a transfer device such as a storage elevator for transferring the wafer cassette, and the transfer device. A wafer flat zone alignment unit for inspecting and rearranging the flat zone alignment of the wafers loaded on the wafer cassette stage transferred through the wafer, a wafer transfer device for transferring the finished wafers, and wafers transferred from the wafer transfer device It may include a process chamber for performing an etching process with respect to the cooling unit for cooling the wafers after the etching process.

Here, after the plurality of wafers loaded in the wafer cassette are transferred to the wafer flat zone alignment unit through the transfer device, the wafers are subjected to the warped state and rearrangement of the flat zone.

Subsequently, after the flat zones of the wafers are aligned, the wafer transfer apparatus transfers the wafers to the process chamber, and the process chamber performs an etching process on the wafers.

The wafers subjected to the etching process in the process chamber are transferred to the cooling unit through a wafer transfer device. Subsequently, the cooling unit cools the wafer. For example, the wafer is seated in the chuck, and the wafer is cooled by nitrogen gas supplied through the chuck to the bottom of the seated wafer.

The wafers cooled to a predetermined temperature in the cooling unit are reloaded into the wafer cassette through the wafer transfer device, and the wafer cassette is remounted into the wafer cassette stage through the transfer device.

However, prior to performing the etching process on the wafers, the process is performed by checking the flat zone alignment state of the wafers loaded in the wafer cassette as described above through the separate wafer flat zone alignment unit, thereby increasing the working time and equipment. There is a problem that decreases the productivity of the product.

Accordingly, the present invention has been made to solve the above problems, an object of the present invention is a wafer for manufacturing a semiconductor device capable of inspecting the alignment of the plurality of wafer flat zones loaded on the wafer cassette on the wafer cassette stage The present invention provides a cassette stage and a wafer flat zone alignment inspection method using the same.

The present invention provides a wafer cassette stage for manufacturing a semiconductor device and a wafer flat zone alignment inspection method using the same.

In one embodiment according to an aspect of the present invention, the wafer cassette stage is a sensor mounted on the stage body and vertically spaced apart from the flat zone of the wafer and the stage body on which the wafer cassette on which the wafer is loaded is mounted. It includes.

In another embodiment, the plurality of sensors may be mounted to the stage body, and may be mounted to the stage body to be positioned above the wafer cassette.

In another embodiment, the sensor may be any one of an optical sensor, an infrared sensor, and a distance sensor.

In another embodiment, the stage body is provided spaced apart a predetermined distance, and further comprising a wafer transfer device for picking up the wafer and to transfer to a predetermined position, the sensor is a control unit for controlling the operation of the wafer transfer device Is electrically connected to the controller, and the controller may stop the operation of the wafer transfer device when the flat zone of the wafer is twisted by receiving an electrical signal from the sensor.

In one embodiment according to another aspect of the present invention, a wafer cassette loaded with a plurality of wafers is seated on a stage body, and the wafer flat zone is twisted at a plurality of positions spaced a predetermined distance from the flat zone of the wafers. Detecting a state, and comparing and analyzing a detection result of the warp state of the wafer flat zone.

In another embodiment, according to the result of the comparative analysis, it is determined whether the etching process for the wafers, the etching process for the wafers is performed when the wafer flat zone is normally aligned in a plurality of positions, In the case where any one of the plurality of positions of the wafer flat zone is misaligned, the method may further include extracting the misaligned wafer.

In another embodiment, there is provided a sensor mounted vertically spaced apart from the wafer flat zone, the sensors each emit light to the wafer flat zone to receive the light reflected from the wafer flat zone It is possible to detect the warpage of the wafer flat zone.

Hereinafter, an embodiment of a wafer cassette stage for a semiconductor device manufacturing apparatus according to an aspect of the present invention will be described with reference to the accompanying drawings.

1 is a perspective view showing a wafer cassette stage for manufacturing a semiconductor device of the present invention.

Referring to FIG. 1, the wafer cassette stage includes a stage body 200 on which a wafer cassette 300 loaded with a plurality of wafers W is mounted. The stage body 200 is disposed near the seating portion 210 on which the wafer cassette 300 is seated, and the seating portion 210, and the wafer W provided in the facility 100 is loaded. And a loading unit 110 that can be unloaded.

A wafer cassette transfer device 120 may be provided inside the loading unit 110 to load and unload the wafer cassette 300 to a process chamber not shown.

The stage body 200 may further include a support 220 positioned above the wafer cassette 300.

In addition, the wafer cassette stage is mounted on the support part 220 of the stage body 200, and is disposed to be mounted upward from the wafer cassette 300, and is spaced vertically from the wafer flat zone FZ by a predetermined distance. It may be provided with a sensor 400 that is arranged.

The sensor 400 may be mounted in plural to the support 220, and may be mounted in three.

Although not shown in the drawing, the sensor 400 includes a light sensor configured to emit light toward the upper surface of the wafer flat zone FZ, and a light sensor configured to receive light reflected from the wafer flat zone FZ. Can be.

In addition, the sensor 400 may be electrically connected to the control unit 500 that controls the operation of the wafer cassette transfer device 120. The controller 500 may stop the operation of the wafer cassette transfer device 120 when the wafer flat zone FZ is turned on by receiving an electrical signal from the sensors 400.

It will be described the operation and effect of the embodiment of the wafer cassette stage according to an aspect of the present invention through the configuration as described above.

Referring to FIG. 1, a plurality of wafers W to be processed may be loaded onto the wafer cassette 300. The wafer cassette 300 may be seated on the seating portion 210 of the stage body 200. The wafer cassette 300 may be directly seated on the seating part 210 by an operator, and a separate wafer cassette transporter (not shown) picks up the wafer cassette 300 on the seating part 120. It can also be seated.

Subsequently, the sensors 400 may detect distortion of the wafer flat zone FZ loaded in the wafer cassette 300.

2 to 3, the mounting position and operation of the sensors 400 will be described in more detail.

FIG. 2 is a plan view of the wafer cassette shown in FIG. 1 and shows the light divergence positions of the sensors.

As shown in FIG. 1, the plurality of sensors 400 are positioned at three positions A, B, C, and FIG. 2 of the upper surface of the wafer flat zone FZ, as shown in FIG. 2. It may be disposed on the support 220 to emit light.

The three positions A, B, and C are positions A, B, and C of the upper surface of the wafer flat zone FZ, as shown in FIG. 2. The A and B positions are positions of both sides of the upper surface of the wafer flat zone FZ, and the B position may be an intermediate position between the A and B positions.

In addition, the sensors 400 may include a first sensor 410, a second sensor 420, and a third sensor 430 mounted to the support part 220 upward from the A, B, and C positions, respectively. Can be.

Therefore, as shown in FIG. 2, light emitted from the light emitting units of the sensors 400 may be reflected at the A, B, and C positions, and the reflected light may be received at the light receiving unit. The sensors 400 may transmit an electrical signal to the controller 500. In this case, the controller 500 may determine that the wafer flat zone FZ is normally aligned.

Subsequently, the controller 500 may transmit an electrical signal to the process driving unit 510 (see FIG. 4) to drive the wafer cassette transfer device 120 (see FIG. 1). The wafer cassette transfer device 120 may pick up the wafer cassette 300 and load it into the loading unit 110. A wafer transfer apparatus not shown in the loading unit 110 may pick up the wafers W and load the wafers into the process chamber.

Therefore, the control unit 500 reflects the light emitted from the light emitting units of the three sensors 410, 420, and 430 as described above at all the plurality of positions A, B, and C of the wafer flat zone. When the received light is received by the light receiving unit, the normal etching process may be performed on the wafers W as described above.

On the other hand, the control unit 500 may determine that the wafer flat zone (FZ) is turned off when the light receiving unit of any one of the sensors (410, 420, 430) does not receive the light reflected as described above. have.

3 is a view showing that the wafer flat zone is twisted.

Referring to FIG. 3, the light emitters of the sensors 400 may emit light toward an upper surface of the wafer flat zone FZ. In this case, when the wafer flat zone FZ is turned to one side, the light emitted from the light emitting parts of the second and third sensors 420 and 430 located above the B and C positions is transferred to the wafer flat zone FZ. Because it is out of the area of), it cannot be reflected. Therefore, the light receiving parts of the second and third sensors 420 and 430 may not receive the reflected light.

Subsequently, the sensors 400 may transmit an electrical signal to the controller 500, and the controller 500 may determine that the wafer flat zone FZ is turned in the above case.

Subsequently, referring to FIG. 4, the controller 500 may transmit an electrical signal to the process driving unit 510 to stop the operation of the wafer cassette transfer device 120. Of course, the operation of the wafer transfer device (not shown) mounted in the loading unit 110 may be stopped.

As described above, in the state where the wafer cassette 300 is seated on the seating portion 210 of the stage body 200, the flat zone FZ of the wafers W is twisted through the sensors 400. By sensing the control process, such as the operation of the wafer cassette transfer device 120, it is possible to reduce the work time, compared to proceeding the process by aligning the wafer flat zone (FZ) separately in the prior art. Thereby, product productivity of an installation can be improved.

Meanwhile, in the above embodiment, the sensors 400 are optical sensors having a light emitting unit and a light receiving unit. For example, although not shown in the drawing, the sensors 400 may be ultrasonic sensors or distance sensing sensors. Either one may be adopted.

In this case, when the sensors 400 are adopted as ultrasonic sensors, the ultrasonic sensors emit ultrasonic waves to a plurality of positions of the upper surface of the wafer flat zone FZ, and ultrasonic waves reflected from the wafer flat zone FZ. Receiving can detect the misalignment state of the wafer flat zone (FZ).

In addition, when the sensors 400 are adopted as a distance sensor, the distance sensor emits ultrasonic waves to a plurality of positions of the upper surface of the wafer flat zone FZ, and the upper surface of the wafer flat zone FZ. The distance received may be calculated by receiving the reflected ultrasonic waves from the and calculating the time until the reflected and returned. Here, the controller 500 may determine that the wafer flat zone FZ is twisted when the distance values calculated at the plurality of positions are not the same.

Of course, it is preferable to mount the sensors 400 to the support 220 to be positioned above the wafer cassette 300 as in the embodiment, but the sensors are not shown. 400 may be disposed vertically downward from the wafer flat zone FZ on the stage body 200.

Therefore, the sensors 400 may detect the normal alignment of the wafer flat zone FZ below the wafer flat zone FZ.

The following describes an embodiment of the wafer flat zone alignment inspection method according to another aspect of the present invention.

5 is a flowchart showing a wafer flat zone alignment inspection method of the present invention.

1 and 5, the wafer flat zone alignment inspection method includes mounting a wafer cassette 300 on which a plurality of wafers W are loaded on a stage body 200 (S10), and The wafer flat zone FZ is disposed at a plurality of positions vertically spaced apart from the flat zone FZ of the wafers W loaded on the wafer cassette 300 by being seated on the stage body 200. Detecting a misalignment state (S20) and comparing and analyzing a sensing result of the misalignment state of the wafer flat zone (FZ) (S30).

Here, the method of detecting the twisted state of the wafer flat zone is as follows.

Referring to FIG. 1, light emitting parts of the sensors 400 emit light to an upper surface of the wafer flat zone FZ, and light reflected from an upper surface of the wafer flat zone FZ is applied to the sensors ( Each of the light receiving units 400 may receive a light.

Subsequently, the sensors 400 may transmit electrical signals to the controller 500 that is electrically connected. In this case, the controller 500 may determine that the wafer flat zone FZ is normally aligned.

In the comparative analysis step (S30), the control unit 500 determines whether the etching process for the wafers (W) according to the comparison analysis result (S40), the wafer flat zone (FZ) is normal When the wafers W are aligned, an etching process is performed on the wafers W, and when the wafer flat zone FZ is twisted, the wafers W having the flat zone FZ twisted are withdrawn (S50). It may further include.

As illustrated in FIG. 3, when any one of the wafer flat zones FZ of the wafers W is twisted, the light receiving units may not receive all the light reflected from the upper surface of the wafer flat zone FZ. That is, light reflected at the A position is received, but light reflected at the B and C positions cannot be received. In this case, the controller 500 may determine that the wafer flat zone FZ is turned off.

Referring to FIG. 4, in this case, the control unit 500 may transmit an electrical signal to the process driving unit 510 to stop the operation of the wafer cassette transfer device 120 or stop the etching process.

According to the present invention, a wafer cassette loaded with a plurality of wafers is seated on a wafer stage, and at the same time, the sensors detect the misalignment of the flat zones of the wafers through the sensors, so that the wafers when the wafer flat zones are normally aligned. By immediately proceeding to the process, there is an effect that can easily reduce the work time loss by proceeding the process after aligning the wafer flat zone with a separate wafer alignment device.

Accordingly, there is an effect that can lower the defective rate of the product, improve the quality of the product, and improve the productivity of the facility.

Claims (7)

A stage body on which a wafer cassette on which a wafer is loaded is mounted; And Wafer cassette stage for manufacturing a semiconductor device, characterized in that it comprises a sensor vertically spaced apart from the flat zone of the wafer, mounted on the stage body. The wafer cassette stage of claim 1, wherein a plurality of sensors are mounted on the stage body and mounted on the stage body to be positioned above the wafer cassette. The method of claim 1, The sensor is a wafer cassette stage for manufacturing a semiconductor device, characterized in that any one of an optical sensor, an infrared sensor and a distance sensor. The apparatus of claim 1, further comprising a wafer cassette transfer device installed on the stage body at a predetermined distance and capable of picking up the wafer cassette and transferring the wafer cassette to a predetermined position, wherein the sensor controls the operation of the wafer transfer device. Electrically connected to a control unit, wherein the control unit receives an electrical signal from the sensor to stop the operation of the wafer cassette transfer device when the flat zone of the wafer is twisted. A wafer cassette loaded with a plurality of wafers is seated on a stage body; Detecting a twisted state of the wafer flat zone at a plurality of locations spaced apart from the flat zone of the wafers by a predetermined distance; Wafer flat zone alignment inspection method comprising the step of comparing the results of the detection of the warp state of the wafer flat zone. The method of claim 5, According to the result of the comparative analysis, it is determined whether the etching process for the wafer, the etching process for the wafer when the wafer flat zone is normally aligned in a plurality of positions, and performing a plurality of wafer flat zone And if any one of the positions is misaligned, extracting the misaligned wafer from the flat zone. The method of claim 5, Sensors mounted vertically spaced apart from the wafer flat zone, each of the sensors to emit light to the wafer flat zone to receive the light reflected from the wafer flat zone to determine whether the wafer flat zone is distorted Method for checking the alignment of the wafer flat zone, characterized in that for sensing.

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