TWI823271B - Substrate transfer method - Google Patents

Abstract

The invention provides a substrate transfer method, which includes defining a plurality of substrates stored in a substrate storage area as working substrates and temporary storage substrates. A robotic arm takes out one of the working substrates from the substrate storage area, transfers the working substrate to an alignment unit for alignment, and transfers the aligned working substrate to a load-lock chamber. The robotic arm takes out one of the temporary storage substrates from the substrate storage area, transfers the temporary storage substrate to the alignment unit for alignment, and transfers the aligned temporary storage substrate to a nitrogen buffer chamber. The method of the present invention can avoid forming an oxide layer on the temporary storage substrate, or prevent the photoresist disposed on the temporary storage substrate from absorbing water and deforming, thereby affecting the precision of the line width and line spacing defined by the photoresist.

Description

Board transfer method

The present invention relates to a substrate transfer method that can avoid forming an oxide layer on the surface of a temporary substrate during the subsequent processing of a working substrate, or causing the photoresist on the temporary substrate to absorb water and deform.

Chemical vapor deposition (CVD), physical vapor deposition (PVD) and atomic layer deposition (ALD) are commonly used thin film deposition equipment and are widely used in integrated circuits, light-emitting diodes and displays.

The deposition equipment mainly includes a cavity and a wafer carrying tray, wherein the wafer carrying tray is located in the cavity and is used to carry at least one wafer. Taking physical vapor deposition as an example, a target needs to be placed in the cavity, where the target faces the wafer on the wafer carrier. When performing physical vapor deposition, inert gas and/or reactive gas can be transported into the cavity, bias voltages are applied to the target and the wafer carrier respectively, and the wafers are heated through the wafer carrier. The inert gas in the cavity forms ionized inert gas due to the action of the high-voltage electric field. The ionized inert gas will be attracted by the bias voltage on the target and bombard the target. The target atoms or molecules sputtered from the target are attracted by the bias voltage on the wafer carrier and deposited on the surface of the heated wafer to form a thin film on the surface of the wafer.

In practical applications, multiple wafers are usually placed in a wafer cassette, where the wafer cassette is placed in a wafer storage area. The wafer is then taken out of the wafer box through a robotic arm and transported to the deposition chamber for thin film deposition.

During the film deposition process, other wafers in the wafer box will be idle. It is not until the deposited wafer leaves the deposition chamber that the robot arm will sequentially transfer the other wafers in the wafer box to deposition chamber for deposition.

However, the wafer itself is very easy to oxidize, so after a period of waiting for the idle wafer in the wafer box, an oxide layer will form on the surface of the wafer. This results in inconsistencies in structure and process conditions between wafers that have been deposited with thin films one after another, and may affect the yield of subsequent processes.

In addition, the wafer surface may also have photoresist, and lines with a certain line width or line spacing are defined on the wafer surface through the photoresist. After waiting for a period of time for idle wafers in the wafer box, the photoresist on the surface of the wafer will absorb water vapor and deform, thereby affecting the accuracy of the line width or line spacing defined by the photoresist.

In order to solve the above-mentioned problems faced by the prior art, the present invention proposes a substrate transfer method. During the process of transferring the substrate to the back-end work machine, part of the substrate is transferred to a nitrogen buffer chamber for temporary storage, so as to avoid waiting for the substrate. Oxidation occurring during the process can also prevent the photoresist on the substrate from absorbing water vapor and deforming, and helps improve the stability and accuracy of the process.

An object of the present invention is to provide a substrate transfer method that can divide a plurality of substrates to be processed into a plurality of working substrates and a plurality of temporary storage substrates. In actual applications, each working substrate can be sequentially transported to the back-end work machine for subsequent processes, and each temporary storage substrate can be sequentially transported to a nitrogen buffer chamber for storage.

The nitrogen buffer chamber is filled with nitrogen, which can reduce the chance of the substrate being exposed to oxygen and avoid the formation of an oxide layer on the surface of the substrate. In addition, it can also prevent the photoresist on the substrate from contacting water vapor and causing photoresist deformation. The pressure in the nitrogen buffer chamber is slightly greater than the external pressure, making the temporary substrate During the process of being transported to the nitrogen buffer chamber, external contaminants will not enter the nitrogen buffer chamber along with the temporary storage substrate.

An object of the present invention is to provide a substrate transfer method suitable for a substrate transfer system, wherein the substrate transfer system includes a substrate storage area, a nitrogen buffer chamber, a substrate transfer area and a load lock chamber. The substrate transfer area connects the substrate storage area, the nitrogen buffer chamber and the load interlock chamber, and is used to transfer substrates between the substrate storage area, the nitrogen buffer chamber and the load interlock chamber.

The substrate storage area is used to store a plurality of substrates, where the plurality of substrates can be defined as a plurality of working substrates and a plurality of temporary storage substrates. The robot arm in the substrate transfer area can take out one of the working substrates from the substrate storage area, transfer the working substrate to an alignment unit for positioning, and then transfer the positioned working substrate to the load interlock chamber.

Afterwards, the robot arm in the substrate transfer area will continue to take out one of the temporary substrates from the substrate storage area, transfer the temporary substrate to the alignment unit for positioning, and then transfer the positioned temporary substrate to the nitrogen buffer chamber for storage .

The load interlock chamber can be connected to a working machine table, wherein the transfer arm in the working machine table is used to transport the working substrate in the load interlocking cavity to the working machine table, and perform thin film deposition on the working substrate in the working machine table. During the film deposition process on the working substrate, the temporary substrate will be stored in a nitrogen buffer chamber to avoid the formation of an oxide layer on the surface of the temporary substrate and to avoid the photoresist water absorption deformation on the surface of the substrate.

In order to achieve the above purpose, the present invention proposes a substrate transfer method, which is suitable for a substrate transfer system. The substrate transfer system includes a substrate storage area, a nitrogen buffer chamber, a substrate transfer area and a load interlock chamber. The substrate The transfer area is connected to the substrate storage area and nitrogen buffer Cavity and load interlock cavity, the substrate transfer method includes: defining a plurality of substrates in the substrate storage area as a plurality of working substrates and a plurality of temporary storage substrates; taking out one of the working substrates from the substrate storage area; aligning the working substrate; Transfer the aligned working substrate to the load interlock chamber; take out one of the temporary storage substrates from the substrate storage area; align the temporary storage substrate; and transfer the aligned temporary storage substrate to the nitrogen buffer chamber.

The present invention proposes another substrate transfer method, which is suitable for a substrate transfer system. The substrate transfer system includes a substrate storage area, a nitrogen buffer chamber, a substrate transfer area and a load interlock cavity. The substrate transfer area is connected to the substrate storage area. area, a nitrogen buffer cavity and a loading interlock cavity. The substrate transfer method includes: defining a plurality of substrates in the substrate storage area as a plurality of working substrates and a plurality of temporary storage substrates; taking out one of the temporary storage substrates from the substrate storage area; Align the temporary storage substrate; transfer the aligned temporary storage substrate to the nitrogen buffer chamber; take out one of the working substrates from the substrate storage area; align the working substrate; and transfer the aligned working substrate to the load interlock chamber body.

The substrate transport method includes: transporting the working substrate in the loading interlock cavity to a working machine, where the working machine is connected to the loading interlocking cavity; and performing thin film deposition on the working substrate in the working machine.

The substrate transport method includes: transporting the working substrate with film deposition completed in the working machine to the loading interlock chamber; and transporting the working substrate with film deposition completed in the loading interlock cavity to the substrate storage area.

The substrate transfer method includes: all working substrates have been taken out from the substrate storage area; the temporary storage substrates in the nitrogen buffer cavity are transported to the loading interlock cavity; and the temporary storage substrates in the loading interlock cavity are transported to the working machine. platform; and perform thin film deposition on the temporary substrate in the working platform.

The substrate transport method, wherein the working machine platform includes a first deposition chamber and a second deposition chamber, the substrate transport method includes: transporting the working substrate in the load interlock chamber to the first deposition chamber; and The first thin film deposition is performed on the working substrate in the first deposition chamber.

The substrate transport method includes: transporting the working substrate in the first deposition chamber to the second deposition chamber; and performing a second thin film deposition on the working substrate in the second deposition chamber.

The substrate transport method includes: transporting the working substrate that has undergone thin film deposition in the second deposition chamber to the load interlock chamber.

10:Substrate transfer system

11:Substrate transfer area

111: Robotic arm

113: Alignment unit

12:Substrate

121:Working substrate

123: Temporary substrate

13:Substrate storage area

15:Loading the interlocking cavity

17: Nitrogen buffer chamber

171:Storage cavity

172:Storage space

173:Nitrogen source

1731:First air intake line

1732:First valve

1733:Second air intake line

1734:Second valve

1736:Needle valve

175: Air extraction unit

1751:Exhaust pipeline

1753: Check valve

1755:Hygrometer

177: Pressure gauge

179: Pressure relief valve

19:Working machine

191:Conveying cavity

193: First deposition chamber

195: Second deposition chamber

[Fig. 1] is a schematic structural diagram of an embodiment of the substrate transfer system of the present invention.

[Fig. 2] is a step flow chart of an embodiment of the substrate transfer method of the present invention.

[Fig. 3] is a schematic structural diagram of an embodiment of the nitrogen buffer chamber of the substrate transfer system of the present invention.

[Fig. 4] is a step flow chart of another embodiment of the substrate transfer method of the present invention.

Please refer to FIGS. 1 and 2 , which are respectively a schematic structural diagram of an embodiment of a substrate transfer system and a step flow chart of an embodiment of a substrate transfer method of the present invention. As shown in the figure, the substrate transfer system 10 mainly includes a substrate transfer area 11 , at least one substrate storage area 13 , at least one load lock chamber 15 and at least one nitrogen buffer chamber 17 . The substrate transfer area 11 connects the substrate storage area 13, the load interlock chamber 15 and the nitrogen buffer chamber 17, and is transferred between the substrate storage area 13, the load interlock chamber 15 and the nitrogen buffer chamber 17 through the substrate transfer area 11 Substrate 12.

The substrate storage area 13 is used to store a plurality of substrates 12, some of the substrates 12 are defined as a plurality of working substrates 121, and other substrates 12 are defined as a plurality of temporary storage substrates 123. As shown in step 21. For example, the number of working substrates 121 and temporary storage substrates 123 may be the same or similar. In addition, after the working substrate 121 leaves the substrate storage area 13, it will undergo subsequent processes, such as a deposition process, while the temporary storage substrate 123 will not immediately undergo subsequent processes after leaving the substrate storage area 13.

In actual applications, the substrate 12, the working substrate 121 and the temporary storage substrate 123 may have gone through processes such as exposure and development. The surfaces of the substrate 12, the working substrate 121 and the temporary storage substrate 123 have photoresist, and the substrate 12 is exposed through the photoresist. Lines with a certain line width and line spacing are defined on the working substrate 121 and the temporary storage substrate 123 .

The substrate transfer area 11 includes a robot arm 111 . The robot arm 111 is used to transport the substrate 12 between the substrate storage area 13 , the load lock chamber 15 and the nitrogen buffer chamber 17 . In one embodiment of the present invention, the robot arm 111 is used to take out one of the working substrates 121 from the substrate storage area 13 and transport the working substrate 121 in the substrate transfer area 11 . The robot arm 111 can then transfer the taken-out working substrate 121 to the alignment unit 113 and align the working substrate 121 through the alignment unit 113, as shown in step 23.

The alignment unit 113 may include a turntable and a detection unit, such as an optical detection unit. The robot arm 111 places the substrate 12 on the turntable, and uses the turntable to drive the substrate 12 to rotate. At the same time, the detection unit detects the angle recognition feature of the substrate 12. For example, the angle recognition feature can be a flat edge or a notch on the substrate 12. ). The aligned substrate 12 will be rotated to the same angle to facilitate subsequent processing or storage of the substrate 12 .

The robot arm 111 takes out the aligned working substrate 121 from the alignment unit 113 and transfers the working substrate 121 to the load interlock chamber 15 , as shown in step 25 .

Specifically, the substrate transfer area 11 can be connected to a working machine 19 through the load lock cavity 15 . After the working substrate 121 is transferred to the load interlock chamber 15, the air extraction of the load interlock chamber 15 is connected. The motor will extract the gas in the load-lock chamber 15 so that the working substrate 121 in the load-lock chamber 15 is in a low pressure or vacuum state.

The robot arm 111 takes out one of the temporary storage substrates 123 from the substrate storage area 13 and transports the temporary storage substrate 123 in the substrate transfer area 11 . Then, the robot arm 111 transfers the taken-out temporary storage substrate 123 to the alignment unit 113, and aligns the temporary storage substrate 123 through the alignment unit 113, as shown in step 27.

The robot arm 111 takes out the aligned temporary substrate 123 from the alignment unit 113, and transfers the aligned temporary substrate 123 to the nitrogen buffer chamber 17 for storage, as shown in step 29.

Figure 3 is a schematic structural diagram of an embodiment of the nitrogen buffer chamber 17, which mainly includes a storage chamber 171, a nitrogen source 173, that is, a pumping unit 175, wherein the nitrogen source 173 and the pumping unit 175 are fluidly connected to the storage cavity. 171.

The storage cavity 171 may be a sealed cavity and includes a storage space 172 for storing the temporary storage substrate 123 . The nitrogen source 173 may be a nitrogen storage barrel, and is used to deliver nitrogen to the storage chamber 171 so that the storage space 172 is filled with nitrogen, where the proportion of oxygen or water gas in the storage space 172 is very low.

In one embodiment of the present invention, the nitrogen source 173 can be fluidly connected to the storage space 172 of the storage cavity 171 through a first air inlet line 1731 and a second air inlet line 1733, and can be connected through the first air inlet line 1731 and the second air inlet line 1733. The air inlet pipeline 1733 delivers nitrogen gas to the storage space 172 , for example, the first air inlet pipeline 1731 is connected in parallel with the second air inlet pipeline 1733 , where the flow rate of the nitrogen gas delivered by the first air inlet pipeline 1731 may be greater than that of the second air inlet pipeline 1733 .

A first valve 1732 can be disposed on the first air inlet line 1731, and by opening or closing the first valve 1732, it is controlled whether the nitrogen source 173 delivers nitrogen to the storage space 172 through the first air inlet line 1731. In addition, a second valve 1734 and a needle valve can be provided on the second air inlet pipeline 1733. 1736, wherein the second valve 1734 is in series with the needle valve 1736. The second valve 1734 is used to control whether the nitrogen source 173 delivers nitrogen to the storage space 172 through the second air inlet line 1733, and the needle valve 1736 is used to fine-tune the flow rate delivered to the storage space 172 through the second air inlet line 1733.

The air extraction unit 175 is fluidly connected to the storage space 172 of the storage cavity 171 and is used to pump out the gas in the storage space 172. For example, the air extraction unit 175 may be an air extraction motor. In an embodiment of the present invention, the air extraction unit 175 can be fluidly connected to the gas in the storage space 172 through a air extraction pipeline 1751. A check valve 1753 and a hygrometer 1755 can be provided on the exhaust pipeline 1751. The check valve 1753 is connected in series with the hygrometer 1755. For example, the check valve 1753 is connected to the storage space 172 via the hygrometer 1755. The hygrometer 1755 is used to measure the humidity in the storage space 172, and the check valve 1753 is used to prevent external gas from entering the storage space 172 through the exhaust pipeline 1751.

Through the arrangement of the storage cavity 171, the nitrogen source 173, and the exhaust unit 175, the storage space 172 of the storage cavity 171 can be filled with nitrogen, and the pressure in the storage space 172 can be greater than the external pressure, for example, greater than 1 atmosphere. Nitrogen has stable chemical properties and does not easily react with the substrate 12 . This prevents an oxide layer from forming on the surface of the temporary substrate 123 stored in the nitrogen buffer chamber 17 , which is beneficial to improving the stability of the temporary substrate 123 in subsequent processes. In addition, since there is very little water vapor in the storage space 172 , the photoresist on the substrate 12 can be prevented from absorbing water vapor and deforming, thereby affecting the accuracy of the line width and line spacing defined by the photoresist.

In one embodiment of the present invention, the storage cavity 171 can also be connected to a pressure gauge 177 and a pressure relief valve 179. The pressure gauge 177 is used to measure the pressure in the storage space 172, and the pressure relief valve 179 is used to discharge the pressure. Gas in storage space 172. For example, when the pressure in the storage space 172 is greater than a preset value, the gas will be discharged from the storage space 172 through the pressure relief valve 179 .

Through the settings of the pressure gauge 177 and the pressure relief valve 179, the pressure in the storage space 172 can be more accurately monitored and controlled, and it is ensured that the storage space 172 is filled with nitrogen and the pressure is slightly greater than the external pressure, so that the temporary storage substrate 123 can enter and exit the storage space. During the process of the cavity 171 , external contaminants will not enter the storage space 172 of the storage cavity 171 along with the temporary storage substrate 12 , which is beneficial to storing the temporary storage substrate 123 .

In actual application, steps 21 to 29 described in Figure 2 can be repeated. In addition, the working substrate 121 in the loading interlock chamber 15 can also be further transferred to the working machine table 19, and subsequent processing can be performed on the working substrate 121. Processes, such as thin film deposition processes.

As shown in FIG. 1 , the substrate transfer area 11 is connected to the working machine table 19 via the load interlock cavity 15 to transport the working substrate 121 in the load interlock cavity 15 to the working machine table 19 . For example, the working machine table 19 can It is a deposition machine and performs thin film deposition on the working substrate 121 . In an embodiment of the present invention, the working machine 19 includes a transport chamber 191, a first deposition chamber 193 and a second deposition chamber 195. The transfer chamber 191 connects the load lock chamber 15 , the first deposition chamber 193 and the second deposition chamber 195 .

A transport arm can be disposed in the transport chamber 191, and the substrate 12 can be transported between the load interlock chamber 15, the first deposition chamber 193 and the second deposition chamber 195 through the transport arm. For example, the working substrate 121 can be transported to The first deposition chamber 193 performs the first thin film deposition, and then the working substrate 121 is transferred from the first deposition chamber 193 to the second deposition chamber 195 for the second thin film deposition.

In addition, during the process of transporting the working substrate 121 from the load lock chamber 15 to the first deposition chamber 193, or transporting the working substrate 121 from the first deposition chamber 193 to the second deposition chamber 195, the substrate transfer area 11 The robot arm 111 inside can perform the above steps 23 to 29 at the same time to improve the efficiency of the process.

After the working substrate 121 in the first deposition chamber 193 and/or the second deposition chamber 195 completes the deposition process, the working substrate 121 with completed film deposition can be transported to the load lock chamber through the transport arm in the transport chamber 191 15. Then, the working substrate 121 that has completed thin film deposition is transported to the substrate storage area 13 through the load interlock chamber 15 through the robot arm 111 in the substrate transfer area 11 .

When all the working substrates 121 in the substrate storage area 13 have been taken out by the robot arm 111, the robot arm 111 in the substrate transfer area 11 will take out the temporary storage substrates 123 in the nitrogen buffer chamber 17 and transport the temporary storage substrates 123. to load interlock chamber 15. Then, the temporary substrate 123 in the load interlock chamber 15 is transported to the first deposition chamber 193 and/or the second deposition chamber 195 of the work table 19 through the transportation arm in the transportation chamber 191, so as to process the work. The temporary substrate 123 in the machine 19 undergoes a thin film deposition process.

The temporary substrate 123 that has completed the deposition process will be transported to the load interlock chamber 15, and then the temporary substrate 123 that has completed the deposition process will be transported to the substrate storage area 13 through the robot arm 111 in the substrate transfer area 11 until all work is completed. Deposition process of substrate 121 and temporary substrate 123.

As shown in Figure 4, which is a step flow chart of another embodiment of the substrate transfer method of the present invention, some substrates 12 can be defined as a plurality of working substrates 121, and other substrates 12 can be defined as a plurality of temporary storage substrates 123. As shown in step 21. Take out the temporary storage substrate 123 from the substrate storage area 13 , align the temporary storage substrate 123 , and transport the aligned temporary storage substrate 123 to the nitrogen buffer chamber 17 for storage, as shown in step 33 and step 35 .

Then, the working substrate 121 is taken out from the substrate storage area 13 , the working substrate 121 is aligned, and the aligned working substrate 121 is transported to the load interlock chamber 15 , as shown in step 37 and step 39 .

The above is only one of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. That is, all changes in shape, structure, characteristics and spirit described in the patent scope of the present invention may be equal to those described above. Modifications should be included in the patentable scope of the present invention.

Claims (10)

A substrate transfer method, suitable for a substrate transfer system, wherein the substrate transfer system includes a substrate storage area, a nitrogen buffer cavity, a substrate transfer area and a load interlock cavity, the substrate transfer area is connected to the substrate storage area , the nitrogen buffer chamber and the load interlock chamber, wherein the nitrogen buffer chamber includes a storage chamber, a nitrogen source and a pumping unit, the nitrogen source and the pumping unit are directly connected to the storage cavity, The substrate transfer method includes: defining a plurality of substrates in the substrate storage area as a plurality of working substrates and a plurality of temporary storage substrates, wherein the numbers of the working substrates and the temporary storage substrates are the same or similar; taking out the plurality of substrates from the substrate storage area a working substrate; aligning the working substrate; transferring the aligned working substrate to the load interlock chamber; taking out one of the temporary storage substrates from the substrate storage area, wherein the working substrate and the temporary storage substrate Take out the substrate storage area in sequence; align the temporary storage substrate; transfer the aligned temporary storage substrate to the storage cavity of the nitrogen buffer cavity, wherein the storage cavity of the nitrogen buffer cavity The pressure is greater than the substrate transfer area; all the working substrates have been taken out from the substrate storage area; and the temporary storage substrates in the nitrogen buffer chamber are transported to the load interlock chamber. The substrate transfer method according to claim 1, including: transporting the working substrate in the load interlock cavity to a working machine table, wherein the working machine table is connected to the load interlock cavity; and to the working machine table Thin films are deposited on this working substrate. The substrate transfer method as described in claim 2 includes: The working substrate with film deposition completed in the work machine is transported to the load interlock chamber; and the working substrate with film deposition completed in the load interlock chamber is transported to the substrate storage area. The substrate transfer method as described in claim 2 includes: transporting the temporary substrate in the load-lock chamber to the work machine; and performing thin film deposition on the temporary substrate in the work machine. The substrate transfer method according to claim 2, wherein the working machine platform includes a first deposition chamber and a second deposition chamber, and the substrate transfer method includes: transferring the working substrate in the load interlock chamber to a first deposition chamber; and performing a first thin film deposition on the working substrate in the first deposition chamber. The substrate transport method according to claim 5, including: transporting the working substrate in the first deposition chamber to the second deposition chamber; and performing a second thin film on the working substrate in the second deposition chamber. deposition. The substrate transport method according to claim 6, including: transporting the working substrate that has undergone thin film deposition in the second deposition chamber to the load lock chamber. A substrate transfer method, suitable for a substrate transfer system, wherein the substrate transfer system includes a substrate storage area, a nitrogen buffer cavity, a substrate transfer area and a load interlock cavity, the substrate transfer area is connected to the substrate storage area , the nitrogen buffer chamber and the load interlock chamber, wherein the nitrogen buffer chamber includes a storage chamber, a nitrogen source and a pumping unit, the nitrogen source and the pumping unit are directly connected to the storage cavity, The substrate transmission method includes: defining a plurality of substrates in the substrate storage area as a plurality of working substrates and a plurality of temporary storage substrates, wherein the numbers of the working substrates and the temporary storage substrates are the same or similar; Take out one of the temporary storage substrates from the substrate storage area, where the working substrate and the temporary storage substrate are sequentially taken out from the substrate storage area; align the temporary storage substrate; and transfer the aligned temporary storage substrate to the substrate storage area. The storage chamber of the nitrogen buffer chamber, wherein the pressure of the storage chamber of the nitrogen buffer chamber is greater than the substrate transfer area; take out one of the working substrates from the substrate storage area; align the working substrate; The correct working substrates are transferred to the load interlock chamber; all the working substrates have been taken out from the substrate storage area; and the temporary storage substrates in the nitrogen buffer chamber are transferred to the load interlock chamber. The substrate transport method as described in claim 8, including: transporting the working substrate in the load interlock cavity to a working machine table, wherein the working machine table is connected to the load interlock cavity; perform thin film deposition on the working substrate; transport the working substrate with thin film deposition completed in the working machine to the load interlock chamber; and transport the working substrate with thin film deposition completed in the load interlock cavity to the substrate storage district. The substrate transfer method as described in claim 9 includes: transporting the temporary substrate in the load-lock chamber to the work machine; and performing thin film deposition on the temporary substrate in the work machine.

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