JPH10270526A - Substrate container and board carrier device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately grasp the position and number is substrates by attaching a reflector to an inside or an outside of a rear of a substrate container for detecting the number of substrates from one direction and detecting whether or not optical beam is screened by a substrate by reflecting optical beam cast from a projection means of a reflector. SOLUTION: Laser beam is screened by a substrates 2 by moving a hand part 6 up and down by an elevator 10 and in a place whether the substrate 2 does not exist, it is reflected by a corner cube mirror 3 and injected to a photosensor 14. When there is an obstacle on an optical path of a laser, laser beam is scattered, thus reducing a light amount injected to the photosensor 14. Thereby, output of the sensor 14 lowers and shows the presence of the substrate 2 on an optical path. According to this constitution, it is possible to detect the presence or absence of a substrate 2 by observing output of the sensor 14. If the substrate 2 exists on an optical path, output of the photosensor 14 becomes an 'L$ level and if the substrate 2 does not exist, the photosensor 14 is in a fixed level 'H' and shows the presence of the substrate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate storage container for storing a plurality of substrates, such as semiconductor wafers, at regular intervals in a vertical direction, and a substrate transfer apparatus for carrying substrates in and out of the substrate storage container. .

[0002]

2. Description of the Related Art Generally, in a semiconductor manufacturing system, a substrate such as a wafer is moved or transported in a state where the substrate is housed in a container having a large number of slots on both side walls for supporting the side of the substrate. This substrate storage container is used by being installed in an apparatus body for processing or measuring a substrate. The substrate is supplied from the container to the device body,
After processing or measurement is performed here, it is stored again in the substrate storage container, and the entire container is transported to the next step.

Usually, when loading and unloading a substrate from the substrate storage container, a finger is inserted into a gap between the substrates, the substrate is mounted on the finger, and the substrate is moved in and out together with the finger. However, a container usually contains a plurality of substrates, and in order to insert a finger into the gap between the substrates without touching the substrates, it is necessary to accurately grasp the number and position of the substrates in the container. There is.

In order to detect the number and position of substrates in a hand-type substrate transfer device, it has been proposed to detect the position level (height) of each substrate in a substrate storage container using laser light. . It arranges the light emitting element and the light receiving element of the laser light respectively in the horizontal and opposite positions of the substrate stored in the substrate storage container, and
The transmission type infrared laser light that can be transmitted between the substrates is moved up and down relatively to the substrate storage container, and the number or the number of the substrates is measured by measuring the number or the position where the infrared laser light is blocked by the substrate. It was to detect the position.

[0005]

However, in the above detecting device, the light emitting element and the light receiving element are arranged so as to sandwich the front and rear of the substrate storage container for detecting the position of the substrate. There is a problem that a large space becomes large. Furthermore, in the case of the substrate storage container in which the back surface of the substrate storage container is closed, the irradiation light is blocked,
Alternatively, there has been a problem that an optically opaque state occurs due to birefringence depending on a container material, and the light receiving element cannot detect light.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems in the conventional example, and has as its object to accurately detect the position and the number of substrates in a substrate storage container from one direction with respect to the substrate storage container. It is another object of the present invention to provide a substrate storage container capable of detecting the position of a substrate and requiring a small space occupied in the apparatus, and a substrate transfer device for transferring substrates into and out of the container.

[0007]

In order to achieve the above object, a substrate storage container according to the present invention has a plurality of grooves for holding a plurality of flat and thin substrates at regular intervals in a vertical direction. A substrate storage container having a substrate inserted into and taken out of the groove from the front side, wherein a reflector is provided on a back wall. For example, a mirror can be used as the reflector. Further, this mirror can be constituted by a plurality of corner cube mirrors arranged in a plane on the back wall. When the back wall is transparent, the reflector can be provided on both front and back surfaces of the back wall.

Further, the present invention provides a substrate transfer apparatus for carrying a substrate into and out of the substrate storage container, wherein the substrate is stored in the substrate storage container or the substrate storage container. And a hand mechanism for moving the finger horizontally to enter the substrate storage container or to retract from the substrate storage container, relative to the installation location of the substrate storage container. A transport unit movable in the vertical direction, a light projecting unit provided in the transport unit for horizontally irradiating a light beam along the finger to the substrate storage container, and a light projecting unit to the substrate storage container And a light beam irradiated from the front side of the substrate storage container and reciprocated between the reflector on the back wall of the substrate storage container without being blocked by the substrate in the substrate storage container. And a means for adjusting the positional relationship between the finger and the substrate storage container when the finger and the hand mechanism enter the substrate storage container based on the output of the light reception device. It is characterized by doing.

[0009]

In order to detect the number of substrates from one direction with respect to the substrate storage container, a reflection plate is attached to the inside or outside of the back surface of the substrate storage container, and the light is emitted from the light emitting means by the reflection. By reflecting the light beam and detecting whether the light beam is blocked by the substrate with the light receiving means,
The number of substrates in the substrate storage container can be known.

Further, when a corner cube mirror is used as a reflection, even if the light beam emitted by the light projecting means is incident on the substrate storage container at an angle, the corner cube mirror always reflects incident light. Since the reflected light can be returned in parallel, erroneous detection regarding the number of substrates can be eliminated.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of the present invention, a substrate accommodating container (cassette) is provided with a groove for mounting a plurality of substrates such as semiconductor wafers at a constant pitch in a vertical direction on a side wall. A reflector is provided on at least both sides and on the wall surface of the cassette opposite to the substrate outlet. The substrate transfer device includes a finger for storing or removing a substrate with respect to the cassette, and a hand mechanism used to move the finger horizontally to enter the cassette or to retract from the cassette. A transport unit that is vertically movable relative to the installation location of the cassette, and a light emitting unit that is provided in the transport unit and irradiates the cassette with light in the horizontal direction along the fingers. And a light-receiving means (sensor) for detecting the beam that has passed without being blocked by the substrate reflected by the reflection inside the rear surface of the cassette, and using the output of the sensor, And adjusting the positional relationship between the finger and the cassette when entering the cassette by the hand mechanism. Perform the loading and unloading. Reflection Yuichi is, for example, a corner cube mirror.

In order to detect the number of substrates in one direction from the cassette, a corner cube mirror is attached to the inside or outside of the back of the cassette, and the laser light emitted from the light emitting element is reflected by the corner cube mirror. The number of substrates in the cassette can be known by detecting whether or not the laser light is blocked by the substrate with the light receiving element.

Further, even if the laser beam emitted by the light emitting element is incident on the cassette at an angle, the corner cube mirror can always return the reflected light parallel to the incident light. Detection can be eliminated.

Further, even if the laser beam emitted by the light emitting element enters the cassette at an angle, the reflected light can always be returned parallel to the incident light by the corner cube mirror. Detection can be eliminated.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a side view of a substrate storage container, a substrate position detecting mechanism, and a substrate transport mechanism according to one embodiment of the present invention. In this embodiment, as shown in FIG. 1, a finger 5 as a substrate holding portion is provided at a position facing a substrate insertion / removal opening (front) of the substrate storage container 1. The hand unit 6 can bend the first hand arm 7 and the second hand arm 8 for linear movement, and the hand unit 6 is rotated to change the direction of the substrate held on the finger 5 surface. A substrate transport mechanism is constituted by a hand rotating unit 9 used at times and a hand lifting unit 10 capable of moving up and down by rotating a ball screw 11 while the hand unit 6 itself is guided by a linear guide 12. ing.

A substrate storage container 1 capable of vertically storing a load, for example, 25 substrates, is placed on a container mounting table 4 at a position facing the transport mechanism.
Inside the back surface (back wall 30), two or more corner cube mirrors 3 are provided in a plane perpendicular to the substrate storage direction, and are arranged at positions corresponding to the grooves of the substrate storage container 1.

A plurality of substrates 2 are stored in the substrate storage container 1.
In order to insert the substrate between the adjacent substrates 2, it is necessary to accurately detect the position of the substrate. Therefore, the hand position 6 is used by incorporating a substrate position detecting mechanism.

The basic structure of the substrate position detecting mechanism is as follows. The light emitting element 13 and the irradiation light (laser) 15 emitted from the light emitting element 13 are reflected toward the corner cube mirror 3 while the corner cube mirror is Half mirror 17 transmitting laser 16 reflected by 3
And a light receiving element 14 for detecting the laser transmitted through the half mirror 17. In order to eliminate the need for position correction due to the level (height) difference between the finger 5 and the laser light path, it is desirable that the level between the finger 5 and the laser light path be extremely close.

When the hand unit 6 is moved up and down by the elevating device 10, the laser beam is blocked by the substrate 2 or, when there is no substrate 2, reflected by the corner cube mirror 3 and incident on the light receiving element 14. . If there is an obstacle on the optical path of the laser, the laser light is scattered, and the amount of light incident on the light receiving element 14 decreases, so that the output of the sensor 14 decreases, indicating that the substrate 2 is on the optical path. Thus, if the output of the light receiving element 14 is viewed, the substrate 2
Can be detected. If the substrate 2 exists in the optical path, the output of the light receiving element 14 goes to the “L” level, and if the substrate 2 does not exist, the output of the light receiving element 14 goes to a certain “H” level. You can know its existence. If the output of the light receiving element 14 is made to cooperate with the lifting device 10, the position of the substrate 2 in the substrate storage container 1 can be known.

FIG. 2 is an enlarged view of the front view of the substrate storage container 1, and the corner cube mirror 3 is disposed inside the back surface of the substrate storage container 1. A substrate holding claw 18 and a groove 19 for holding a substrate are provided on both left and right side surfaces (side walls 40) of the substrate storage container 1, and a plurality of substrates 2 are held in the substrate storage container 1 by the substrate holding claw 18. Have been.
The corner cube mirror 3 is provided between the horizontal center lines of the substrate holding claws 18 vertically adjacent to each other in the vertical direction.
Are arranged horizontally without gaps.

FIG. 3 is a sectional view taken along line BB of FIG. Groove 1
9, the substrate 2 exists between the pitches of the corner cube mirror 3. FIG.
3 is an enlarged view of FIG.
Are not held, and c and d are corner-gebulated mirrors 3 where the substrate 2 is held between the grooves 19.
Shows an optical path when a laser beam is irradiated perpendicularly to the installation surface of the laser beam. If the substrate 2 is on the laser beam path,
The laser light is scattered and the optical path of the laser is interrupted. In FIG. 4A, the light that has entered the corner cube mirror 3 is specularly reflected by the first reflecting surface 20 and is incident on the second reflecting surface 21, and is also specularly reflected by the second reflecting surface 21. Since the corner angle of the corner cube mirror 3 is set to a right angle, the sum of the complex angles of the incident light 15 and the reflected light 16 becomes 180 degrees, and the reflected light 16 can be returned by the corner cube mirror 3 in parallel with the incident light 15.

FIG. 5 shows a case where the laser is irradiated while being inclined with respect to the installation surface of the corner cube mirror 3. Also in this case, the corner cube mirror 3
Of the incident light 15 and the reflected light 1
6 becomes 180 degrees, and the reflected light 16 can be returned by the corner cube mirror 3 in parallel with the incident light 15. As a result, the corner cube mirror 3
The reflected light can be reliably returned to the light receiving element 14 regardless of whether the laser beam is incident perpendicularly or inclined.

The output voltage of the light receiving element 14 corresponding to FIG. 3 is as shown in FIG. 6. At each slot position, if the voltage goes to "L" level, a substrate exists, and the voltage goes to "H" level. Indicates that the substrate does not exist.

FIG. 7 shows a state in which the corner cube mirrors 3 in the vertical direction are arranged in the substrate storage container 1 with an interval therebetween. The output voltage of the light receiving element 14 corresponding to FIG. 7 is shown in FIG. It represents. When the corner cube mirror 3 is disposed in the vertical direction, the interval between the corner cube mirrors 3 is intentionally increased so that the mirror is not reflected at the position of the substrate holding claw 18 of the substrate storage container, and the output from the light receiving element 14 is output. The voltage becomes “L” level, and the position of the slot can be detected simultaneously with the position of the substrate 2.

FIG. 9 is a sectional view taken along the line CC of FIG. Even if the horizontal laser light is inclined with respect to the substrate storage container 1, the horizontal corner angle of the corner cube mirror 3 is also set at a right angle, so that the corner cube mirror 3 reflects the reflected light 16 in parallel with the incident light 15. Can be returned. Thus, the substrate 2 can be detected even when the installation surface of the corner cube mirror 3 is slightly inclined with respect to the substrate storage container 1 or when the substrate storage container 1 is slightly inclined and is installed on the container installation table 3. . Further, since two or more corner cube mirrors 3 are arranged in the horizontal direction, it is possible to more reliably return the reflected light to the light receiving element.

FIG. 10 shows a cross section of a substrate storage container in which a corner cube mirror is manufactured by making a notch on the outside of the wall surface of the substrate storage container 3 opposite to the substrate take-out opening and depositing the cut surface with a metal such as aluminum. FIG. Even if the corner cube mirror is provided on the outside of the wall surface of the substrate storage container 3 opposite to the substrate take-out opening, if the substrate storage container is made of a transparent material, the same as the embodiment described above is obtained. The effect can be obtained.

Thus, even if the corner cube mirror 3 is set to be slightly inclined with respect to the substrate storage container 1,
Further, when the substrate storage container 1 is tilted with respect to the laser beam, even if the corner cube mirror 3 is tilted with respect to the laser beam, the reflected light 16 can be returned to the incident light 15 in parallel to the light receiving element. 2 can be detected without error.

In the above embodiment, one corner cube mirror is provided for the pitch of the substrate holding claws.
A similar effect can be obtained by making the corner cube mirror finer and providing a plurality of corner cube mirrors for one pitch of the substrate holding claws. Also,
By making the vertical and horizontal dimensions of the corner cube mirror smaller than the width of the laser light, the scattering of the laser light at the edge of the corner cube mirror can be averaged, and the optical path of the incident light and the reflected light can be reduced. Since the difference can be reduced, the presence or absence of the substrate 2 in the substrate storage container 1 can be detected more accurately. In the above-described embodiment, the hand and the position detection device are movable and the substrate storage container is fixed, but it is sufficient that the substrate storage container and the position detection device move relatively.

[0029]

[Embodiment of Device Production Method] Next, an embodiment of a device production method using the above-described exposure apparatus or exposure method will be described. FIG. 11 shows a flow of manufacturing micro devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, etc.). In step 1 (circuit design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 12 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer. In the present embodiment, in each of the repetitive processes, the above-described substrate storage container storing the semiconductor wafer is transported to a position corresponding to the process and installed.
The semiconductor wafer is taken out of the substrate storage container by the above-described substrate transfer device, processed according to a process, and stored in the above-described substrate storage container using the above-described substrate transfer device.

By using the production method of this embodiment, it is possible to produce a highly integrated device at a low cost, which was conventionally difficult to produce.

[0032]

As described above, according to the present invention, since the reflector is provided on the wall (back wall) facing the substrate insertion / removal opening in the substrate storage container, it is arranged in one direction with respect to the substrate storage container. The relative position between the substrate and the finger can be accurately detected by the light projecting means and the light receiving means, and accurate loading and unloading of the substrate can be performed. Further, if the reflector is a mirror having a corner cube shape, the reflector can return the reflected light parallel to the incident light even if the incident light of the light projecting means is relatively inclined with respect to the reflector.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention.

FIG. 2 is an enlarged view of a cross section taken along the line AA in FIG. 1, and is a front view of the substrate storage container in the embodiment of FIG.

FIG. 3 is a cross-sectional view taken along line BB in FIG. 2, and is a side view of the substrate storage container in the embodiment of FIG.

FIG. 4 shows an optical path of a laser when an installation surface of a corner cube mirror is perpendicular to laser light.

FIG. 5 shows an optical path of a laser when an installation surface of a corner cube mirror is inclined with respect to a laser beam.

FIG. 6 shows an output from a light receiving element corresponding to FIG.

FIG. 7 shows a state where the corner cube mirrors 3 in the vertical direction are arranged in a substrate storage container with an interval therebetween.

FIG. 8 shows an output voltage from the light receiving element corresponding to FIG.

9 is a cross-sectional view taken along the line CC in FIG. 2, and is a top view of the substrate storage container in the embodiment of FIG.

FIG. 10 is a cross-sectional view of a substrate storage container provided with a corner cube mirror on the outside of the wall surface opposite to the substrate outlet.

FIG. 11 is a diagram showing a flow of manufacturing a micro device.

FIG. 12 is a diagram showing a detailed flow of a wafer process in FIG. 11;

[Explanation of symbols]

1: substrate storage container, 2: substrate, 3: corner cube mirror, 4: container mounting table, 5: finger, 6: hand unit, 9: hand rotating unit, 10: elevating device, 13: light receiving element, 14: light emission Element, 30: back wall, 40: side wall.

Claims (6)

[Claims] 1. A plurality of grooves for holding a plurality of flat and thin substrates at predetermined intervals in a vertical direction on at least left and right side walls, and a substrate is inserted into and removed from the grooves from the front. A substrate storage container, comprising a reflector on a back wall of the substrate storage container. 2. The substrate storage container according to claim 1, wherein the reflector is a mirror. 3. The substrate storage container according to claim 2, wherein the mirror is a plurality of corner cube mirrors arranged in a plane on the back wall. 4. The substrate storage container according to claim 1, wherein the back wall is transparent, and the reflector is provided on a back surface of the back wall. 5. A substrate transport apparatus for carrying a substrate into and out of the substrate storage container according to claim 1, wherein the substrate is stored in the substrate storage container or the substrate storage. A finger mechanism for removing the finger from the container, and a hand mechanism for moving the finger horizontally to enter the substrate storage container or to retract from the substrate storage container, relative to the installation location of the substrate storage container. A light transfer means provided in the transfer part for irradiating the substrate storage container with a light beam in a horizontal direction along the fingers; and a light projection means for the substrate storage container. A light beam irradiating from the front side of the substrate storage container and reciprocating between the reflector on the back wall of the substrate storage container without being blocked by the substrate in the substrate storage container. A light receiving unit for detecting a system; and a unit for adjusting a positional relationship between the finger and the substrate storage container when the finger and the hand mechanism enter the substrate storage container based on an output of the light receiving unit. A substrate carrying-in / out device. 6. A semiconductor device manufactured by using the substrate storage container according to claim 1 or the substrate transfer device according to claim 5.