JPH07142549A - Semiconductor production device - Google Patents

Abstract

PURPOSE:To reduce the errors of photoresist coating thickness due to the temperature difference of wafers, development size, superposition, etc., by measuring and controlling wafer temperatures immediate by before the wafers are treated. CONSTITUTION:A wafer 2 in a container 1 is placed in an interface unit 3 and carried to a baking unit 5 by a carrying arm 9. The baked wafer 2 is conveyed to a cooling unit 6, and the temperature of the wafer is lowered down to a temperature proper to coating treatment. The carrying arm 9 moves, and the temperature of the wafer 2 is measured in a noncontact manner by an infrared temperature measuring device 10 installed in front of a coating unit 7. The wafer is carried to a treatment unit and treatment is started when the temperature of the wafer is kept within a temperature range proper to treatment, and the carrying arm 9 is brought to the state of standby and the temperature of the wafer is corrected and treatment is conducted when the temperature of the wafer is outside the range. Accordingly, the error of the temperatures of the wafers at the time of the treatment of the wafers is reduced, and the accuracy of photo-resist coating-film thickness and photo-resist development size, superposition, etc., at the time of exposure can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly to a technique effectively applied to wafer temperature control in a semiconductor manufacturing apparatus in which the temperature of the wafer influences processing.

[0002]

2. Description of the Related Art As a semiconductor manufacturing apparatus, there is a method of accommodating a plurality of processing units in a chamber or a clean room and performing integrated automatic processing. Taking a wafer resist processing apparatus as an example, each unit such as a coating unit and a bake unit and a transfer unit are provided in a thermal chamber, and a wafer is transferred between the units by a transfer arm of the transfer unit to perform sequential processing. It is configured to do.

The unprocessed wafer is stored in a storage jig, carried into an interface unit of the resist processing apparatus, taken out from the storage jig by a transfer arm, and is first transferred to a bake unit for pre-baking and other wafer surfaces. Hydrophobic treatment is performed, and after baking treatment, the wafer is placed on a cooling plate kept at a constant temperature for a certain period of time to lower the wafer temperature to a temperature suitable for the coating process and then transferred to a coating unit for resist coating process. Then, the wafer for which the coating process has been completed is again conveyed to the bake unit and the pre-bake process is performed.

During this time, the temperature inside the thermal chamber is kept constant to eliminate the influence of the outside air temperature, and the conveyance time from the end of the cooling process to the photoresist coating process is kept constant, so that the temperature inside the thermal chamber is affected. Is made uniform, and the temperature of the wafer during the coating process is kept at an appropriate temperature.

Other processes, such as photoresist development, have the same structure. A wafer is placed on a cooling plate kept at a constant temperature for a certain period of time and transferred in a thermal chamber kept at a constant temperature for a certain period of time. By doing so, the temperature of the wafer during processing is kept constant. The same applies to the exposure apparatus.

As described above, in the conventional apparatus, the temperature control of the wafer is controlled by the temperature of each processing unit such as a cooling plate, the temperature inside the thermal chamber, and the transfer time.

[0007]

The inventor of the present invention has conducted a detailed investigation on the temperature of a wafer to be transferred between the units in the above-mentioned apparatus. As a result, the fluctuation range of the temperature of the wafer is larger than previously thought. Turned out to be big. When the cause was investigated, the following problems were found.

The temperature inside the thermal chamber of the conventional apparatus has a fluctuation range of about 0.5 ° C., but it sometimes fluctuates within a range of a few degrees. Further, since the temperature distribution in the thermal chamber is not always constant due to the flow of air in the thermal chamber, a temperature difference occurs depending on the location.

Regarding the bake unit or the cooling unit, an error occurs in the wafer temperature because the processing is completed at a predetermined time even when the temperature inside the apparatus is not constant at the time of starting the apparatus. I will end up.

Since the transfer arm is also exposed to various temperature environments, it cannot be expected to always maintain a constant temperature condition, and the temperature of the transfer arm may affect the wafer.

Further, when a plurality of wafers are transferred by a single arm, a waiting time may occur even after completion of processing for a predetermined time, which causes fluctuations in the wafer payout tact time and affects the wafer temperature. Sometimes.

Due to these circumstances, even if the temperature of the wafer is not suitable for the processing, the next wafer processing is performed in a preset procedure. However, the photoresist coating film thickness varies. Similarly, when the exposure process is performed, the wafer expands and contracts depending on the wafer temperature, so that the overlay error increases. In addition, when development processing is performed,
Since the development speed varies depending on the wafer temperature, the photoresist development dimension changes.

An object of the present invention is to reduce the error in the wafer temperature during wafer processing by measuring and controlling the wafer temperature during transfer, and to improve the accuracy of the photoresist coating film thickness, photoresist development dimension, overlay during exposure, etc. It is to provide technology that can be improved.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0015]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

A wafer temperature measuring device is provided near the transfer port of each processing unit or in the transfer arm to measure the wafer temperature immediately before the wafer processing. As a result of the measurement, if the wafer temperature is within the temperature range suitable for processing, the wafer is transferred to the processing unit to start processing, and if the wafer temperature is outside the temperature range suitable for processing, the transfer arm is used. After the wafer temperature is corrected on the transfer path in the standby state, the wafer is transferred to the processing unit and the processing is started.

[0017]

According to the above-mentioned means, the wafer temperature during processing can be kept constant by measuring and controlling the wafer temperature immediately before the wafer processing. It is possible to reduce errors such as size and overlay, which stabilizes product quality, improves characteristics, and improves yield.

The structure of the present invention will be described below together with embodiments.

In all the drawings for explaining the embodiments, parts having the same function are designated by the same reference numerals, and the repeated description thereof will be omitted.

[0020]

(Embodiment 1) FIG. 1 is a plan view showing a schematic configuration of a semiconductor manufacturing apparatus according to an embodiment of the present invention. In this embodiment, the present invention is applied to a wafer photoresist coating device.

The semiconductor manufacturing apparatus of this embodiment is provided with a housing jig 1.
An interface unit 3 for delivering and receiving the wafer 2 stored in the storage unit, a transfer unit 4 for transferring the wafer between the processing units, and a bake unit 5 for heating the wafer.
And a cooling unit 6 for cooling the baked wafer 2,
A coating unit 7 for coating a photoresist on the wafer 2 is provided in a thermal chamber (not shown). The transport unit 4 has a transport path 8 facing the transport port of each processing unit.
And a transfer arm 9 that holds the wafer 2 and moves on the transfer path 8. The wafer 2 is transferred between the processing units by the transfer arm 9 and sequentially processed.

In this embodiment, an infrared temperature measuring device 10 for measuring the temperature of the wafer in a non-contact manner is provided in front of the transfer port of the coating unit 7 as a temperature measuring section. This temperature measuring instrument 1
0 can be attached to the transfer arm 9 and may be additionally provided before the bake unit 5 and the cooling unit 6.

The unprocessed wafer 2 is stored in the accommodating jig 1, carried into the interface unit 3 of the resist processing apparatus, taken out of the accommodating jig 1 by the transfer arm 9 of the transfer unit 4, and first transferred to the bake unit 5. After being conveyed, pre-application baking and surface hydrophobic treatment are performed. After the bake treatment, the wafer 2 is transferred to the cooling unit 6 by the transfer arm 9 and placed on a cooling plate (not shown) kept at a constant temperature for a certain period of time, so that the wafer temperature raised by the baking is increased. Lower to a temperature suitable for coating process.

After the cooling process, the transfer arm 9 moves to the transfer port of the coating unit 7, and the temperature of the wafer 2 is monitored without contact by the infrared temperature measuring device 10 installed in front of the coating unit.

The control of the present apparatus is performed as shown in FIG. 2, and the temperature information of the wafer 2 monitored by the infrared temperature measuring device 10 which is a temperature measuring unit is sent to the temperature judging unit so that the temperature of the wafer 2 is detected. It is determined whether or not the temperature is within the set temperature range suitable for processing, and the determination result is sent to the device control unit.

When the temperature of the wafer 2 is within the set temperature range, the apparatus controller sends a signal to the transfer arm 9 to transfer the wafer 4 to the coating unit 7 and start the coating process. However, when the temperature of the wafer 2 is out of the set temperature range, the apparatus control unit puts the transfer arm 9 in the standby state.
While in the standby state, the temperature of the wafer 2 is corrected by the clean air in the thermal chamber blown from above. When the temperature of the wafer 2 becomes within the set range by this correction, the apparatus control unit releases the standby of the transfer arm 9, transfers the wafer 2 from the transfer arm 9 to the coating unit 7, and starts the coating process. As a control of the present apparatus, the present invention can be implemented by adopting a method in which a temperature change of the wafer 2 is predicted from the recorded data by additionally providing a data recording section to shorten or extend the transfer time.

The wafer 2 on which the resist coating process has been completed is
After being conveyed again to the bake unit 5 and subjected to the pre-bake process, it is conveyed to the interface unit 3 again and is conveyed out of the apparatus in a state of being accommodated in the accommodation jig 1. The processed wafer 2 is transferred to another interface unit 11 and transferred to an exposure unit (not shown) connected via the interface unit 11,
It is also possible to adopt a configuration in which the exposure process is performed continuously.

When the temperature of the wafer 2 is not corrected within a predetermined time when the temperature of the wafer 2 is corrected, or when the temperature error of the wafer 2 is too large to be corrected when the temperature of the wafer 2 is measured, When an abnormality occurs, the device control section 7 puts the transport arm 9 in a temporary stop state, and notifies the abnormality by an appropriate notifying means (not shown) such as lighting of a display lamp and generation of a warning sound. It is configured to notify the operator.

(Embodiment 2) FIG. 3 is a plan view showing a schematic structure of a semiconductor manufacturing apparatus according to another embodiment of the present invention.
In this embodiment, the present invention is applied to a wafer photoresist coating device.

In the semiconductor manufacturing apparatus of this embodiment, an interface unit 3, a transfer unit 4, a bake unit 5, a cooling unit 6 and a coating unit 7 are provided in a thermal chamber (not shown). The transfer unit 4 includes a transfer path 12 facing the transfer port of each processing unit and a plurality of transfer arms 9 that hold the wafer 2 and move on the transfer path 12.
It is configured to be transported between the processing units and sequentially processed.

Since the plurality of transfer arms 9 move, the transfer path 12 is formed in an annular shape, and the transfer path 12 does not interfere with the movement of the other transfer arms 9 so that the transfer path 12 has a standby portion 13 in the transfer path 12. Is provided. A heat source (not shown) for temperature correction is provided in the standby unit 13, but a hot plate, a cooling plate, or the like can be considered as the heat source, and air is blown out from the thermal chamber in this standby unit. Air may be used as a heat source.

In this embodiment, as the temperature measuring unit, an infrared temperature measuring device 10 for contactlessly measuring the temperature of the wafer is attached to the transfer arm 9. The temperature measuring device 10 includes a baking unit 5, a cooling unit 6, It is also possible to provide it in front of the transfer port of the coating unit 7. Further, a thermocouple or the like may be provided on the transfer arm 9 or the like as a temperature measuring device.

The unprocessed wafer 2 is stored in the accommodating jig 1, carried into the interface unit 3 of the resist processing apparatus, taken out of the accommodating jig 1 by the transfer arm 9 of the transfer unit 4, and first transferred to the bake unit 5. After being conveyed, pre-application baking and surface hydrophobic treatment are performed. After the bake treatment, the wafer 2 is transferred to the cooling unit 6 by the transfer arm 9 and placed on a cooling plate (not shown) kept at a constant temperature for a certain period of time, so that the wafer temperature raised by the baking is increased. Lower to a temperature suitable for coating process.

After the cooling process, the transfer arm 9 moves to the transfer port of the coating unit 7, and the temperature of the wafer 2 is monitored without contact by the infrared temperature measuring device 10 installed in front of the coating unit.

The control of this apparatus is performed as shown in FIG. 2, and the temperature information of the wafer 2 monitored by the infrared temperature measuring instrument 10 which is the temperature measuring section is sent to the temperature determining section so that the temperature of the wafer 2 is detected. It is determined whether or not the temperature is within the set temperature range suitable for processing, and the determination result is sent to the device control unit.

When the temperature of the wafer 2 is within the set temperature range, the apparatus controller sends a signal to the transfer arm 9 to deliver the wafer 4 to the coating unit 7 and start the coating process. However, when the temperature of the wafer 2 is out of the set temperature range, the apparatus control unit puts the transfer arm 9 in the standby state.
While in the standby state, by a heat source (not shown),
The temperature of the wafer 2 is corrected. When the temperature of the wafer 2 becomes within the set range by this correction, the apparatus control unit releases the standby of the transfer arm 9, transfers the wafer 2 from the transfer arm 9 to the coating unit 7, and starts the coating process. As the control of the present apparatus, it is possible to continuously measure the temperature change of the wafer by attaching the temperature measuring device 10 to the transfer arm 9. Therefore, the temperature of the wafer being transferred can be appropriately checked to check the temperature of the wafer 2. It is also possible to adopt a method of predicting a change and shortening or extending the transportation time.

The wafer 2 on which the resist coating process has been completed is
After being conveyed again to the bake unit 5 and subjected to the pre-bake process, it is conveyed to the interface unit 3 again and is conveyed out of the apparatus in a state of being accommodated in the accommodation jig 1. The processed wafer 2 is transferred to another interface unit 11 and transferred to an exposure unit (not shown) connected via the interface unit 11,
It is also possible to adopt a configuration in which the exposure process is performed continuously, or to perform the development process in a continuous manner by replacing one of the coating units 7 with a development processing unit.

When the temperature of the wafer 2 is not corrected within a predetermined time when the temperature of the wafer 2 is corrected, or when the temperature of the wafer 2 is measured, the error in the temperature of the wafer 2 is so large that it is difficult to correct the temperature. When an abnormality occurs, the device control section puts the transport arm 9 in a temporary stop state, and an operator notifies the operator of the occurrence of the abnormality by an appropriate notification means (not shown) such as lighting of a display lamp and generation of a warning sound. It is configured to notify.

As described above, the invention made by the present inventor is
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

In the above-mentioned embodiment, the example in which each unit is housed in the thermal chamber has been described, but the present invention is similarly applied to the case where each unit is installed open in the clean room.

The present invention can be applied not only to the resist coating apparatus but also to the exposure processing apparatus and the developing apparatus, as well as other automatic integrated processing apparatuses in general.

[0042]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) According to the present invention, there is an effect that the wafer temperature can be controlled by monitoring the wafer temperature immediately before wafer processing and during wafer transfer by the transfer arm.

(2) Due to the effect (1), the wafer temperature before the photoresist coating process can be controlled to be constant, so that the variation in the photoresist coating film thickness due to the wafer temperature difference during the photoresist coating process can be reduced. There is an effect.

(3) Because of the effect (1), the wafer temperature before the photoresist coating process can be controlled to be constant. Therefore, the variation in the photoresist developing speed due to the wafer temperature difference during the photoresist coating process can be reduced to reduce the developing size. There is an effect that the accuracy can be improved.

(4) Due to the effect (1), the wafer temperature before the photoresist exposure processing can be controlled to be constant, so that the pattern superposition is suppressed by suppressing the expansion and contraction of the wafer due to the wafer temperature difference during the photoresist exposure processing. There is an effect that the accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a semiconductor manufacturing apparatus according to an embodiment of the present invention,

FIG. 2 is a diagram illustrating control of a semiconductor manufacturing apparatus that is an embodiment of the present invention,

FIG. 3 is a plan view showing a semiconductor manufacturing apparatus according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Housing jig, 2 ... Wafer, 3, 11 ... Interface unit, 4 ... Transport unit, 5 ... Bake unit,
6 ... Cooling unit, 7 ... Coating unit, 8, 12 ... Transport path, 9 ... Transport arm, 10 ... Infrared temperature measuring device (temperature measuring unit), 13 ... Standby unit.

Front page continuation (72) Inventor Yoichiro Tamiya 3-3 Fujibashi, Ome, Tokyo 2-3 Hitachi Tokyo Electronics Co., Ltd. (72) Innovator Shinya Ogane 3-3 Fujibashi, Ome, Tokyo 2 Hitachi Tokyo Electronics Incorporated (72) Inventor Kiyoto Muramo 3-3 Fujitobashi 2-3, Ome-shi, Tokyo Hitachi Tokyo Electronics Co., Ltd. (72) Inventor Shinkichi Hirota 3-chome 2 Fujibashi, Ome-shi, Tokyo 2 Hitachi Tokyo Electronics Co., Ltd. In-house (72) Inventor Keizo Kuroiwa 5-20-1, Kamimizuhonmachi, Kodaira-shi, Tokyo Incorporated company Hitachi Ltd. Semiconductor Division

Claims (5)

[Claims] 1. In a semiconductor manufacturing apparatus in which a plurality of processing units are provided in a chamber and a transfer unit moves wafers between the processing units, a temperature measuring unit for measuring the temperature of the wafer is processed outside the processing units. A semiconductor manufacturing apparatus provided in at least one of a unit and a transport unit. 2. In a semiconductor manufacturing apparatus in which a plurality of processing units are provided in a chamber and a plurality of transfer units move the wafers between the processing units, a temperature measuring unit for measuring the temperature of the wafer is provided outside the processing units. 2. The semiconductor manufacturing apparatus according to claim 1, wherein the semiconductor manufacturing apparatus is provided with a standby section that is provided on a transport path along which the transport unit moves and that allows another subsequent transport unit to precede. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the temperature measuring unit is provided on a transfer arm of the transfer unit. 4. The semiconductor manufacturing apparatus according to claim 1, wherein the temperature measuring unit is provided near a wafer transfer port of the processing unit. 5. The semiconductor manufacturing apparatus according to claim 2, wherein the standby section is provided with a heat source.