KR101927340B1 - Apparatus for inspecting wafer mapping - Google Patents

Abstract

The present invention relates to a wafer mapping inspection apparatus inspecting the loading state of a plurality of wafers loaded in a wafer storage container. The present invention includes a lifting and lowering unit including a stator formed along a wafer loading direction and a mover lifted and lowered along the stator; a sensor unit sensing wafer loading or non-loading while moving along the mover; and a measurement unit including a wire having one end connected to the mover and a drum around which the other end of the wire is wound and which is fixedly disposed on one side of the lifting and lowering unit and measuring the unwinding length of the wire unwound from the drum. Information on the loading or non-loading and the unwinding length is transmitted, the wafer loading state is inspected in accordance with the unwinding length, and the normality of the loading state is determined. Accordingly, the present invention physically measures a position of the sensor unit while smoothly moving the sensor unit to figure out an accurate position.

Description

[0001] APPARATUS FOR INSPECTING WAFER MAPPING [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer mapping inspection apparatus, and more particularly, to a wafer mapping inspection apparatus for inspecting a plurality of wafers loaded on a wafer storage container.

In a semiconductor process, a wafer processing process transfers wafers to various process chambers and processes wafers. At this time, in order to minimize adhesion of foreign matter or contaminants to the wafer while transferring the wafer from one process chamber to another process chamber, there is provided a wafer storage container capable of storing a plurality of wafers, to be.

The wafer storage container is provided with a plurality of wafers for each loading position, and the stored wafers are transferred from the wafer storage container to the process chamber by the transfer robot.

However, in the case where the wafer is not loaded at the loading position of the wafer storage container or an error occurs in which two or more wafers are loaded, the transfer robot skips the loading position or removes the overlapped wafers It must go through. Therefore, it is necessary to check the loading state of the wafers loaded in the wafer storage container.

Korean Patent Registration No. 10-0576199 discloses that when a plurality of wafers are mounted on each end of a shelf in a port, troubles occur in each processing step. Further, in a device for detecting wafers, there is a case where the sensor is moved by using a driving means which is not necessarily stable in speed, such as an air-driven cylinder, in order to make a simple structure. If detection is performed by moving the sensor by such a driving means, an error becomes large and it becomes difficult to accurately detect the wafer. The present invention provides a wafer processing apparatus comprising a permeation sensor for wafer detection, a dog including an indicator means, and a permeation sensor for a dog, wherein a signal duration from the permeation sensor and a signal duration from the permeation sensor for dog And a wafer processing apparatus for determining the number of wafers by comparing the ratio with a preset threshold value.

[0004] In Korean Patent Registration No. 10-0749756, there are disclosed a rodless cylinder which is vertically movable with respect to a main housing, and a forward-backward movement means which is fixed on a mover of a rodless cylinder so as to fix the door- And a solenoid valve operating mechanism for shutting off or shutting off the air pressure so that the rodless cylinder can be intermittently stopped at a predetermined position so that the wafer alignment state detecting device can be made compact, There is disclosed a wafer mapping operation device capable of reducing energy and also reducing the cost of the entire device.

Korean Patent Registration No. 10-1431116 discloses a door opening / closing unit for a door opening / closing apparatus, comprising: a pair of operating bars, each of which is rotatably coupled with a first shaft, ; The two corner portions are rotatably coupled to the other end of each operation bar on the second axis so as to connect the other ends of the respective operation bars and each of the mounting portions is extended from the corner region to form a sensing space between the mounting portions A sensor mounting member of the sensor; An optical sensor electrically connected to the control unit and provided at each of the mounting units on both sides; And driving means provided on the bottom surface of the mounting plate and connected to one end of one of the operating bars to rotate the operating bar so that the sensing space of the sensor mounting member is selectively positioned inside the FOUP, The operation of the sensor can be simplified by expanding or folding the sensor mounting member, and the sensor can be buried to prevent damage or contamination of the sensor.

 The prior art described above has a position sensor for measuring the position of a sensing sensor for sensing a wafer and a member having a transmitting portion and a non-transmitting portion at regular intervals such as a dog. This allows the position sensor to determine the position of the sensor and the position sensor by measuring the number of changes of the signal by the transmissive portion and the non-transmissive portion.

However, this method has a problem in that it is impossible to accurately grasp the position of the sensing sensor because it is possible to grasp the position gradually according to the section where the position sensor is changed into the transmission portion and the non-transmission portion.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wafer mapping inspection apparatus for inspecting the exact position of a sensing sensor and checking the loading state of the wafer.

A wafer mapping inspection apparatus for inspecting a stacking state of a plurality of wafers stacked on a wafer storage container, the apparatus comprising: a stator formed along the stacking direction of the wafers; A lifting and lowering portion made up of a shifter moving up and down along the stator; A sensor unit moving along the mover and sensing whether the wafer is loaded; A measuring unit configured to measure a length of the wire wound from the drum, the wire having one end connected to the mover and a drum wound around the other end of the wire and fixed to one side of the ascending and descending portion; An inspection unit that receives information on the loading status and the winding length and checks the loading status of the wafers according to the winding length and determines whether the loading status is normal; And a control unit for controlling the ascending and descending of the ascending and descending portion; .

Preferably, a temperature sensor for measuring the wire or the ambient temperature of the wire; And the inspection unit corrects the roll-up length calculated from the rotation amount of the drum in accordance with the temperature measured from the temperature sensor.

Preferably, the inspection unit corrects the winding length by the following equation.

Preferably, the inspection unit corrects the take-up length by receiving measured temperature information from the temperature sensor when the wafer storage container is opened or closed.

Preferably, the inspection unit inspects the stacking state including the stacking state and whether there are two or more stacked wafers, at the stacking position of the wafers.

Preferably, the wire is wound in parallel with the stator.

Preferably, the controller moves the mover in one direction, performs a first inspection, returns the mover in the opposite direction, and performs a second inspection.

Preferably, the sensor unit includes a light-emitting sensor and a light-receiving sensor disposed on the same plane as the wafer with the wafer therebetween to sense whether the wafer is loaded or not according to whether the light-receiving sensor is receiving light, And a sensor forward / backward member for moving the light receiving sensor back and forth from the mover in the wafer direction; .

Preferably, the control unit controls the sensor forward / backward member to advance the light emission sensor and the light reception sensor when the wafer is not sensed at the wafer loading position.

Preferably, the controller moves the mover in one direction, performs a primary inspection, and moves the mover to a loading position of the wafer on which the wafer is not sensed, so that the sensor forward / Control to advance the sensor.

The wafer mapping inspection apparatus of the present invention can smoothly move the sensor section by the ascending and descending section.

In addition, according to the present invention, the position of the sensor unit can be physically measured by the measuring unit including the wire and the drum, so that the accurate position can be grasped.

Further, according to the present invention, it is possible to check the stacking state according to the winding length to judge whether the stacking state is normal or not, and thereby to control the ascending and descending of the ascending and descending section.

In addition, the present invention is equipped with a temperature sensor, and it is possible to precisely grasp the length of the winding by correcting the change in the length of the wire according to the temperature.

In addition, the present invention can minimize the sensing error of the sensor unit by performing the primary and secondary tests

Further, according to the present invention, by including the sensor forward / backward member, it is possible to grasp the loading of the wafers of different sizes or the defective loading.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a wafer mapping inspection apparatus according to the present invention. FIG.
2 is a view showing a state in which a wafer mapping inspection apparatus according to the present invention inspects a wafer having a normal stacking state.
FIG. 3 is a graph showing a sensing signal according to the position of the sensor unit on the basis of FIG. 2;
4 is a view showing a state in which a wafer mapping inspection apparatus according to the present invention inspects a wafer having a poor stacking state.
FIG. 5 is a graph showing a sensing signal according to the position of the sensor unit, based on FIG. 4;
6 is a plan view showing a sensor section constituting the present invention.
7 is a plan view showing a state in which the wafer is disposed behind and is not sensed by the sensor unit.
8 is a plan view showing a state in which the sensor unit advances to detect a wafer.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The wafer mapping inspection apparatus of the present invention is an apparatus for inspecting the stacking state of a plurality of wafers loaded on a wafer storage container.

1 to 3, the apparatus for inspecting a wafer according to an embodiment of the present invention includes an ascending and descending section 10, a sensor section 20, a measuring section 30, an inspection section 40, 50, a sensor forward / backward member 60, and a temperature sensor 70.

The ascent / descent section 10 is composed of a stator 11 and a mover 12.

The stator 11 is mounted on the wafer storage container and is formed along a plurality of wafer mounting directions, and preferably has a long bar shape.

The mover 12 moves up and down along the stator 11 and is provided around the outer periphery of the stator 11 to move up and down.

The ascending and descending section 10 may be constituted by a roadless cylinder.

The sensor unit 20 moves along the mover 12 and senses whether or not the wafer is loaded. The loading status means the presence or absence of wafers at each loading position where wafers are loaded in the wafer storage container. The loading positions are the first loading position to the seventh loading position (h1 to h7 ).

The sensor unit 20 may include a light emitting sensor 21, a light receiving sensor 22, and a sensor rod 23, as shown in FIG.

The light emitting sensor 21 and the light receiving sensor 22 are arranged on the same plane as the wafer and are arranged so that the wafer is positioned between the light emitting sensor 21 and the light receiving sensor 22. [ The light emitted from the light emitting sensor 21 is detected by the light receiving sensor 22, and it is possible to determine whether or not the wafer is loaded according to whether the light receiving sensor 22 is detected or not.

Specifically, when light emitted from the light emitting sensor 21 is not detected by the light receiving sensor 22 during the movement of the light emitting sensor 21 and the light receiving sensor 22 along the mover 12, Can be sensed. On the other hand, when light emitted from the light emitting sensor 21 is detected by the light receiving sensor 22 at the loading position, it can be sensed that the wafer is not loaded at the loading position.

The sensor rod 23 connects the light emitting sensor 21 and the light receiving sensor 22 to the mover 12 and is designed not to collide with the wafer when the mover 12 moves up and down.

The measuring unit 30 includes a wire 31 and a drum 32.

One end of the wire 31 is connected to the mover 12 and the other end is wound around the drum 32. At this time, the wire 31 is preferably wound in parallel with the stator 11. Thus, the position of the sensor unit 20 can be grasped directly from the unwound length without a separate calculation process because the length of the wire 31 and the sensor unit 20 are changed equally.

The other end of the wire 31 is wound around the drum 32 and fixedly disposed on one side of the ascending / descending section 10. 2 shows the state of being fixed on the upper side of the ascending / descending section 10, and may be disposed on the lower side of the ascending / descending section 10. [

The measuring unit 30 can measure the position of the mover 12 and the sensor unit 20 by measuring the length of the wire 31 wound from the drum 32. [ This makes it possible to accurately measure the position of the sensor unit 20 by physically measuring the position of the sensor unit 20.

The inspection unit 40 inspects the loading state of the wafers according to the winding length from information on whether the wafers are delivered from the sensor unit 20 and the length of the wafers delivered from the measuring unit 30. Thus, it can be determined whether or not the wafer is normally loaded.

The inspection unit 40 grasps the position of the mover 12 and the sensor unit 20 through the winding length transmitted from the measuring unit 30 and detects the position of the sensor unit 20 through the sensor unit 20, It is determined whether or not the stacking state at each stacking position is normal.

Hereinafter, a process of inspecting the loading state of the wafer by the inspection unit 40 of the present invention will be described in detail with reference to FIGS. 2 to 5, in two cases in which the wafer is loaded.

First, when the mover 12 ascends and descends, the measuring unit 30 measures the length of the wire 31 to be shortened, and the inspecting unit 40 detects the position of the sensor unit 20, Sensing signal.

Fig. 3 shows a sensing signal sensed according to the position of the sensor unit 20, as shown in Fig. 2, in the case of the first case, as shown in Fig. 2, Graph. When the sensing signal is ON, the light emitted from the light emitting sensor 21 is sensed by the light receiving sensor 22, and when the sensing signal is OFF, the light emitted from the light emitting sensor 21 Is not sensed by the light receiving sensor 22, indicating the presence of the wafer.

As shown in Fig. 2, the loading states of the wafers are normal at the respective loading positions h1 to h7. Therefore, as shown in Fig. 3, it can be confirmed that the sensing signal is turned off by the thickness t of the wafer at each of the stacking positions h1 to h7. As a result, the inspection unit 40 can check that the wafer is in a normal load state.

4 is a graph showing a sensing signal sensed according to the position of the sensor unit 20 on the basis of FIG. 4 .

As shown in Fig. 4, the loading states of the wafers at the first and second loading positions h1 and h2 and the fourth and fifth loading positions h4 and h5 are normal. Therefore, as shown in Fig. 5, it is confirmed that the sensing signal is turned off by the thickness t of the wafer at the first and second stacking positions h1 and h2 and the fourth and fifth stacking positions h4 and h5 have.

Two wafers are stacked at the third stacking position h3. Thus, the sensing signal is turned off by the thickness 2t of the two wafers at the third stacking position h3 in Fig.

No wafers are loaded in the sixth loading position h6. As a result, the sensing signal remains in the ON state at the sixth mounting position h6 in Fig.

Thus, the inspection unit 40 can check the stacking state including whether or not the wafers are stacked and whether or not the wafers are stacked.

The control unit 50 controls the ascending and descending of the ascending and descending section 10 and controls the forward and backward movement of the sensor forward and backward member 50 to be described later.

The control unit 50 may carry out the first inspection while moving the ascending and descending part 10 in one direction and return the ascending and descending part 10 to the opposite direction and perform the secondary inspection.

For example, the mover 12 ascends and descends, performs a primary inspection, descends, and performs a secondary inspection. On the other hand, the mover 12 may descend and perform a primary inspection, elevate and perform a secondary inspection.

This improves the inspection accuracy of the loading state of the wafer and minimizes the sensing error of the sensor unit.

The sensor forward / backward member 60 causes the light emitting sensor 21 and the light receiving sensor 22 to move back and forth from the mover 12 in the wafer direction. The sensor forward / backward member 60 advances the light emission sensor 21 and the light reception sensor 22 at the stacking position where the wafer is not sensed. As a result, the size of the wafer is small or the wafer is misaligned.

6, one side of the wafer W is positioned between the light emitting sensor 21 and the light receiving sensor 22, and the wafer W is placed on the wafer W. In this case, It is possible to determine whether or not it is loaded.

7, when the wafer W is positioned rearwardly of the normal position W ', the wafer W is placed at the stacking position, but the wafer W is positioned between the light emitting sensor 21 and the light receiving sensor 22 Since it is not sensed, it can not be checked whether it is loaded or not. At this time, when the light emitting sensor 21 and the light receiving sensor 22 are moved forward by the sensor forward / backward member 60, it is possible to sense the wafer W disposed rearwardly.

This can be done not only in the case of a wafer arranged rearwardly but also in the case of a substrate having a small size.

On the other hand, wafers of various sizes can be sensed according to the forward and backward positions of the sensor forward / backward member 60. For example, a wafer having a small size can be inspected in an advanced state, and a wafer having a large size can be inspected in a backward state.

Hereinafter, a method of operating the sensor forward / backward member 60 by the control unit 50 will be described in two ways.

First, when the sensor unit 20 can not sense the wafer at the loading position in the process of moving the mover 12 in one direction, the control unit 50 controls the sensor forward / backward member 60 Controls the light emitting sensor 21 and the light receiving sensor 22 to advance. This makes it possible to immediately check the wafer in the intermediate failure state in which the sensor unit 20 moves in one direction.

As a second method, the control unit 50 moves the mover in one direction and performs a primary inspection by the sensor unit 20. [ Thereafter, in the process of returning to the opposite direction, the mover 12 is moved to the loading position where the wafer is not sensed, and the sensor forward / backward member 60 controls the light emitting sensor 21 and the light receiving sensor 22 to advance . In the first inspection, only the position of the defective wafer passes through the defective wafer, and only the defective wafer can be confirmed again during the second inspection.

The temperature sensor 70 measures the temperature around the wire 31 or the wire 31. Since the winding length of the wire 31 is calculated from the rotation amount of the drum 32, the winding length of the thermally deformed wire 31 can be corrected based on the temperature measured from the temperature sensor 70.

Thus, the inspection unit 40 corrects the length of the wire 31 to be pulled out by the following equation.

Further, the temperature change greatly changes at the time of opening or closing the wafer storage container, and the change in the length of the reel due to thermal deformation of the wire is large. Therefore, the inspection unit 40 receives the measured temperature information from the temperature sensor 70 at the time of opening or closing of the wafer storage container, and corrects the length of the wafer.

While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10:
11: Stator
12: mover
20:
21: Light emitting sensor
22: Light receiving sensor
30:
31: Wire
32: Drums
40:
50:
60: sensor forward / backward member
70: Temperature sensor

Claims (10)

A wafer mapping inspection apparatus for inspecting a stacking state of a plurality of wafers stacked in a wafer storage container,
A rising section formed of a stator formed along the loading direction of the wafer and a moving element moving up and down along the stator;
A sensor unit moving along the mover and sensing whether the wafer is loaded;
A measuring unit configured to measure a length of the wire wound from the drum, the wire having one end connected to the mover and a drum wound around the other end of the wire and fixed to one side of the ascending and descending portion;
An inspection unit that receives information on the loading status and the winding length and checks the loading status of the wafers according to the winding length and determines whether the loading status is normal;
A control unit for controlling the ascending and descending of the ascending and descending portion; And
A temperature sensor for measuring the temperature around the wire or the wire; Lt; / RTI >
Wherein the inspection unit corrects the roll-up length calculated from the rotation amount of the drum in accordance with the temperature measured from the temperature sensor. delete The method according to claim 1,
Wherein the inspection unit corrects the take-up length by the following equation.

The method of claim 3,
Wherein the inspection unit corrects the take-up length by receiving temperature information measured from the temperature sensor when the wafer storage container is opened or closed. The method according to claim 1,
Wherein the inspection unit inspects the stacking state including the stacking state and whether or not the wafers are stacked in a stacked state at the stacking position of the wafers. The method according to claim 1,
Wherein the wire is wound in parallel with the stator. The method according to claim 1,
Wherein the controller moves the mover in one direction and performs a first inspection and returns the mover in the opposite direction and performs a second inspection. The method according to claim 1,
The sensor unit may include a light emitting sensor and a light receiving sensor disposed on the same plane as the wafer with the wafer therebetween to sense whether the wafer is loaded or not according to the light receiving state of the light receiving sensor,
A sensor forward / backward member for moving the light emitting sensor and the light receiving sensor back and forth from the mover in the wafer direction; Further comprising: a memory for storing the wafer mapping information. The method of claim 8,
Wherein the control unit controls the sensor forward / backward member to advance the light emission sensor and the light reception sensor when the wafer is not sensed at the loading position of the wafer. The method of claim 8,
Wherein the control unit moves the mover in one direction and performs a primary inspection and then moves the mover to a loading position of the wafer on which the wafer is not sensed so that the sensor forward and backward member advances the light emitting sensor and the light receiving sensor The wafer mapping inspection apparatus comprising:

Images