JP2001135702A - Substrate transfer apparatus, substrate treatment apparatus, method of manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the contamination of a water being transferred to a positioning stage, etc., in a low-pressure chamber. SOLUTION: In a low-pressure chamber 1 a down-flow of an atmosphere gas blown out of blowout holes 26 occurs, against which a wafer W held with a substrate holder 13 of a substrate transfer 10 is covered with a cover 12, and a local flow of gas blown via a blowout part 11 out of a branch feed line 22 branched from a circulation feed line 21 of the low-pressure chamber 1 is made to flow in parallel with the wafer W, thereby preventing the wafer W from being contaminated with particles which falls with the down-flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a substrate transfer apparatus, a substrate processing apparatus, and a device manufacturing method for transferring a substrate in a chamber containing an exposure apparatus or the like.

[0002]

2. Description of the Related Art An exposure apparatus as a substrate processing apparatus used for manufacturing a device such as a semiconductor element is an X-ray exposure apparatus that uses X-rays as exposure light along with miniaturization and high integration of the semiconductor element. Promising. When X-rays are used as the exposure light, the X-rays are introduced into the exposure chamber through a beam duct maintained in an ultra-high vacuum because the X-rays are significantly attenuated by the atmosphere. The exposure chamber is a chamber maintained in a reduced pressure atmosphere such as helium gas for the purpose of suppressing X-ray attenuation and promoting heat radiation of the substrate and the mask. Then, the X-rays as exposure light transfer the pattern of the mask held by the mask holding device onto a substrate such as a wafer positioned by the positioning stage.

[0003] The atmosphere in the chamber is controlled to a predetermined value while monitoring pressure, temperature, purity, and the like. In addition, in order to suppress soaring of particles and the like, a so-called downflow airflow is directed downward from above the chamber. Is flowing. On the other hand, the substrate transfer apparatus holds and moves the substrate along a transfer path in the chamber, and automatically performs delivery and the like of the substrate to the positioning stage.

[0004]

However, according to the above-mentioned prior art, a downflow airflow is generated in the chamber as described above, and the substrate is conveyed while being held in a vertical state. In many cases, the downflow airflow directly hits the upper surface of the substrate, and there is an unsolved problem that particles (impurities) flowing down along with the downflow airflow easily adhere to the upper surface of the substrate.

When an airflow due to the downflow hits the upper surface of the substrate, the airflow goes down from the edge of the substrate,
Since the backflow of the air current occurs and winds up the lower particles, there is also an inconvenience that these particles adhere to the substrate.

Further, in the chamber of the exposure apparatus, although a certain down flow is blown downward from above, the substrate transport path is located at the lower part of the chamber, and the positioning stage is located above the substrate transport path. In such a case, the substrate transported along the transport path is most likely to be contaminated by particles flowing down from the stage unit or another unit.

In particular, in proximity gap exposure or the like in which a mask and a substrate are exposed while maintaining a gap of several μm, particles adhering to the substrate cause
There is also a risk of damaging the mask membrane, and particles adhering to the substrate in the transport path must be minimized.

For example, it is necessary to satisfy a strict requirement to keep 0.1 μm of debris on a substrate during transfer of the substrate in the chamber.

The present invention has been made in view of the above-mentioned unsolved problems of the prior art, and can significantly reduce the contamination of a substrate during the transfer of the substrate in a chamber controlled in a down-flow depressurized atmosphere. It is an object of the present invention to provide a substrate transfer device, a substrate processing device, and a device manufacturing method.

[0010]

In order to achieve the above object, a substrate transfer apparatus according to the present invention comprises: a substrate holding means for holding a substrate in a chamber controlled to a downflow atmosphere; It is characterized by having a local airflow blowing means for blowing out a local airflow, and a driving means for integrally moving the substrate holding means and the local airflow blowing means in the chamber.

It is preferable that the local airflow blown from the local airflow blowing means is configured to flow parallel to the surface of the substrate.

It is preferable that a cover is provided parallel to the surface of the substrate.

[0013] The local airflow may be the same gas as the downflow in the chamber.

It is preferable that a sensor for detecting the presence or absence of the substrate on the substrate holding means and a control means for controlling the timing of blowing the local airflow based on the output of the sensor are provided.

[0015]

By generating a local airflow near the substrate such as a wafer for eliminating the downflow in the chamber, the substrate being transported in the chamber is prevented from being contaminated by the downflow particles or the like.

If the local airflow blown from the local airflow blowing means is configured to flow parallel to the surface of the substrate, particles can be effectively removed from the vicinity of the substrate.

If a cover is provided in parallel with the surface of the substrate, it is possible to prevent the turbulence of the local air flow and to more effectively prevent the downflow particles from falling onto the substrate.

If the local airflow is the same gas as the downflow in the chamber, it is possible to prevent the purity of the atmosphere in the chamber from being reduced by the local airflow.

If a sensor for detecting the presence or absence of a substrate on the substrate holding means and a control means for controlling the timing of blowing the local airflow based on the output of the sensor are provided, the substrate is held by the substrate holding means. It can be configured to blow out the local airflow only when there is. by this,
The consumption of expensive atmosphere gas such as helium can be reduced, and the production cost of devices and the like can be reduced.

[0020]

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

FIG. 1 shows an X-ray exposure apparatus as a substrate processing apparatus according to an embodiment, which has a decompression chamber 1 which is a chamber controlled to a decompression atmosphere such as helium gas. Reference numeral 1 denotes a window 1a through which X-rays as exposure light generated from a light source (not shown) are transmitted, and a mask stage 2 for holding an original mask and a substrate transfer device 10 in a reduced-pressure chamber 1. Substrate processing means such as a wafer positioning stage 3 for positioning the wafer W, which is a processed substrate, is provided.

An atmosphere control system for controlling the reduced-pressure atmosphere in the reduced-pressure chamber 1 evacuates an atmospheric gas such as helium gas in the reduced-pressure chamber 1 by a vacuum pump 20a to reduce the vacuum pressure (degree of vacuum) in the reduced-pressure chamber 1. An exhaust line 20 for controlling, connected to the exhaust line 20,
Circulation supply line 2 for recirculating gas into decompression chamber 1
1 and a branch supply line 22 that branches off from the circulation supply line 21 and supplies a part of the gas to the substrate transfer device 10.

The exhaust line 20 includes a vacuum pump 20a such as a dry pump for evacuating atmospheric gas from a suction port 23 disposed below the decompression chamber 1, a flow control valve 20b whose opening can be adjusted, and a controller 24. And a pressure sensor 25 for detecting the pressure in the decompression chamber 1. The controller 24 adjusts the opening of the flow control valve 20 b based on the detection output of the pressure sensor 25, and
The vacuum pressure (for example, 20 kPa) in the decompression chamber 1 is controlled by evacuating the atmospheric gas by 0a.

The circulating supply line 21 has a temperature control unit 21a for controlling the temperature of the gas discharged by the vacuum pump 20a and a flow control unit 21b, and is connected to an outlet 26 in the decompression chamber 1.

The flow control unit 21b recirculates the gas, the temperature of which has been adjusted to a predetermined temperature by the temperature control unit 21a, from the outlet 26 into the decompression chamber 1 at a predetermined flow rate.

A part of the circulation path of the atmosphere gas is provided with a chemical filter (not shown) for removing a reaction product such as ammonium sulfate generated by a chemical reaction with exposure light. This improves the purity of the atmospheric gas in the circulation path, prevents the reaction products from adhering to the mask or the like of the mask stage 2, attenuates the exposure energy, and prevents exposure unevenness from occurring. It is possible to do.

Further, a filter 27 for removing particles is arranged at the outlet 26 to remove particles (impurities) contained in the atmospheric gas blown into the decompression chamber 1.

The atmospheric gas blown into the decompression chamber 1 in this manner is moved downward from above to the positioning stage 3, the mask stage 2, the mask transport device (not shown), and the substrate transport device 10 in the decompression chamber 1. This creates a flow airflow.

The branch supply line 22 is connected to the substrate transfer device 10.
A gas is blown out from the blowing unit 11 which is a local airflow blowing means to generate a local airflow that eliminates a downflow near the wafer W. The substrate transfer device 10 is provided so as to cover the wafer W on the substrate holding unit 13 serving as a substrate holding unit in order to prevent the downflow airflow from hindering the local airflow from the blowing unit 11. Provided, so that the local airflow is blown in parallel to the surface of the wafer W without being disturbed. The airflow flowing parallel to the surface of the wafer W as described above eliminates particles flowing down from the driving unit of the positioning stage 3 together with the downflow airflow in the decompression chamber 1.

Further, the substrate transfer apparatus 10 is provided with a filter 14 as a filter means.
The filter 14 removes particles and the like that are generated when the tube constituting the substrate bends or moves with the movement of the substrate transfer device 10. The purified local airflow thus purified can be blown onto the wafer W.

FIG. 2 is an enlarged view of the substrate transfer device 10, and the substrate holding portion 13 of the substrate transfer device 10
The substrate holding unit 13, the filter 14, the blowing unit 11, and the cover 12 are integrally moved by a driving unit (not shown) to transfer the wafer W to the positioning stage 3 and the like.

The detection output of the pressure sensor 13a, which is a sensor provided in the substrate holding portion 13, is configured to be taken into the CPU 13c, which is a control means, via the sensor distribution 13b. In the sensor distribution 13b, the output of the pressure sensor 13a is used. A signal indicating whether or not the wafer W is present in the substrate holding unit 13 is generated. Then, as shown in the timing chart of FIG.
By outputting an ON / OFF signal from the solenoid valve 13c to the solenoid valve driver 13d, the valve 13e opens and closes, and the blowing timing is controlled such that the local air flow is blown from the blowing unit 11 only when there is a wafer W. I do.

As a result, consumption of expensive atmosphere gas such as helium gas used for local spraying can be reduced, which can contribute to cost reduction.

As shown in FIG. 3, the presence / absence detection of the wafer W does not necessarily have to be performed by vacuum suction. For example, the presence / absence of the wafer W may be detected by a transmission type sensor 13f.

The flow direction of the local airflow blown out from the blowing section 11 of the substrate transfer apparatus 10 does not necessarily need to be parallel to the transfer direction of the wafer W to the positioning stage 3. If the flow direction of the local airflow intersects with the transfer direction of the wafer, for example, if it is configured to be orthogonal, the turbulence of the local airflow during transfer is reduced, and particles near the wafer are more effectively removed. This has the added advantage that it can be removed.

Since the local airflow and the downflow airflow are the same gas, the local airflow causes the decompression chamber 1
There is no danger that the purity of the atmosphere inside will be reduced.

Next, an embodiment of a device manufacturing method using the above-described substrate processing apparatus will be described. FIG. 4 shows a manufacturing flow of a semiconductor device (a semiconductor chip such as an IC or an LSI, or a liquid crystal panel or a CCD). Step 1
In (circuit design), a circuit of a semiconductor device is designed.
Step 2 is a process for making a mask on the basis of the circuit pattern design. Step 3 (wafer manufacturing)
Then, a wafer as a substrate is manufactured using a material such as silicon. 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. 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 an assembly process (dicing, bonding),
It includes steps such as a packaging step (chip encapsulation). 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. 5 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 15
In (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described 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. By using the manufacturing method of this embodiment, it is possible to manufacture a highly integrated semiconductor device, which has been conventionally difficult to manufacture.

[0039]

Since the present invention is configured as described above, it has the following effects.

It is possible to prevent a substrate such as a wafer from being contaminated by particles during transportation in a substrate processing apparatus, which can greatly contribute to higher precision and lower cost of devices and the like.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a substrate processing apparatus according to an embodiment.

FIG. 2 is a view for explaining a substrate transfer apparatus of the apparatus of FIG. 1;
(A) is an enlarged view showing the configuration, and (b) is a timing chart for explaining the opening and closing operation of the valve.

FIG. 3 is a diagram showing a modification.

FIG. 4 is a flowchart showing a device manufacturing method.

FIG. 5 is a flowchart showing a wafer process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Decompression chamber 2 Mask stage 3 Positioning stage 10 Substrate transfer apparatus 11 Blow-out part 12 Cover 13 Substrate holding part 13a Pressure sensor 13f Transmission-type sensor 14, 27 Filter 20 Exhaust line 21 Circulation supply line 22 Branch supply line 23 Suction port 26 Blow-off port

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F031 CA02 GA35 GA36 GA48 JA05 JA10 JA22 JA45 MA27 NA04 NA05 PA23 PA30 5F046 AA22 CD01 CD02 CD04 DA07 DB14 GA08 GA11 GA12 GA14

Claims (10)

[Claims] 1. A substrate holding means for holding a substrate in a chamber controlled in a downflow atmosphere, a local airflow blowing means for blowing a local airflow near the substrate,
A substrate transport apparatus having a driving unit for integrally moving the substrate holding unit and the local airflow blowing unit in the chamber. 2. The substrate transport apparatus according to claim 1, further comprising: a filter unit for purifying a local airflow, wherein the driving unit moves the filter unit together with the substrate holding unit and the local airflow blowing unit. . 3. The substrate transfer device according to claim 1, wherein the local airflow blown from the local airflow blowing means is configured to flow parallel to the surface of the substrate. 4. The substrate transfer apparatus according to claim 1, further comprising a cover disposed parallel to a surface of the substrate. 5. The apparatus according to claim 1, wherein the local air flow is configured to flow in parallel with the substrate transport direction.
5. The substrate transfer apparatus according to any one of claims 4 to 4. 6. The substrate transfer apparatus according to claim 1, wherein the local air flow is configured to intersect with the substrate transfer direction. 7. The substrate transfer apparatus according to claim 1, wherein the local airflow is the same gas as the downflow in the chamber. 8. A system according to claim 1, further comprising a sensor for detecting the presence or absence of a substrate on said substrate holding means, and a control means for controlling a timing of blowing out a local airflow based on an output of said sensor. 8. The substrate transfer device according to claim 7. 9. A substrate processing apparatus comprising: the substrate transfer apparatus according to claim 1; and a substrate processing unit configured to process a substrate in a chamber. 10. A device manufacturing method, comprising a step of manufacturing a device using the substrate processing apparatus according to claim 9.