JP2021048415A - Substrate processing device and substrate for measurement - Google Patents

Abstract

To measure a concentration of a process gas properly by using a simple device.SOLUTION: A hydrophobic treatment device 41 processes a wafer W by using a process gas containing ions and includes: a processing container 300 which stores a wafer W; a gas supply part 320 which supplies a hexamethyldisilazane (HMDS) gas to an interior of the processing container 300; an exhaust part 340 which exhausts air from the interior of the processing container 300; an ion sensor 346 which is provided at a measuring wafer T having the same shape as that of the wafer W and measures a number of the ions contained in the gas in the processing container 300; and a wind speed sensor which is provided at the measuring wafer T with the ion sensor 346 and measures a wind speed above the measuring wafer T.SELECTED DRAWING: Figure 4

Description

The present invention relates to a substrate processing apparatus that processes a substrate to be processed using a processing gas containing ions, and a measurement substrate used in the substrate processing apparatus.

For example, in the photolithography process in the manufacture of a semiconductor device, for example, a hydrophobic treatment for making the surface of a semiconductor wafer (hereinafter referred to as “wafer”) hydrophobic, or a resist solution is applied onto the hydrophobic wafer to form a resist film. A resist coating process, an exposure process for exposing a predetermined pattern to the resist film, a development process for developing the exposed resist film, and the like are sequentially performed to form a predetermined resist pattern on the wafer.

The above-mentioned hydrophobizing treatment is performed to improve the adhesion between the surface of the wafer and the resist film, and is performed to change the surface of the hydrophilic wafer to be hydrophobic. In such a hydrophobizing treatment, a hydrophobizing agent, for example, HMDS (Hexamethyldisilazane) gas is supplied to the surface of the wafer for a predetermined time, and the surface of the wafer and HMDS are chemically reacted. That is, the hydroxyl group on the surface of the wafer is replaced with a trimethylsilanol group by this chemical reaction to make the surface of the wafer hydrophobic. As a result, it is possible to prevent the resist film from peeling off from the surface of the wafer in the subsequent process.

In order to properly perform the above-mentioned hydrophobization treatment, it is important to use an HMDS gas having an appropriate concentration in order to promote the chemical reaction between the wafer and HMDS. If the hydrophobization treatment is not properly performed, the subsequent resist coating treatment is not properly performed, for example, lot defects occur, and the yield is lowered.

Therefore, it is necessary to monitor the concentration of HMDS gas. For example, Patent Document 1 discloses that the concentration of HMDS gas is measured by using a HMDS concentration sensor of a constant potential electrolysis method. _{Further, Patent Document 1 also discloses that the concentration of NH 3} gas generated by the hydrophobization treatment is measured by using a diaphragm electrode type NH _{3 concentration sensor.}

Japanese Unexamined Patent Publication No. 7-142311

However, as in the method described in Patent Document 1 described above, in the case of directly measuring the concentration of the HMDS gas or NH ₃ gas, is expensive concentration sensor used in the measurement, also the large ones.

It is also conceivable to use, for example, an infrared sensor to measure the concentration of the HMDS gas. However, infrared sensors are no longer expensive and large. Therefore, there is room for improvement in the measurement of the HMDS concentration.

The present invention has been made in view of this point, and an object of the present invention is to appropriately measure the concentration of the processing gas by using a simple device.

As a result of diligent studies by the present inventor in order to achieve the above object, it has been found that there is a correlation between the concentration of HMDS gas and the number of ions measured by an ion sensor using HMDS gas. The ion sensor is cheaper and smaller than the conventional concentration sensor and infrared sensor.

The present invention has been made based on such findings, and the present invention is a substrate processing apparatus for processing a substrate to be processed using a processing gas containing ions, and includes a processing container for accommodating the substrate to be processed and a processing container. A gas supply unit that supplies the processing gas to the inside of the processing container, an exhaust unit that exhausts the inside of the processing container, and a measurement substrate having the same shape as the substrate to be processed are provided for the gas inside the processing container. It is characterized by having an ion sensor that measures the number of the contained ions, and a wind velocity sensor that is provided on the measurement substrate together with the ion sensor and measures the wind velocity above the measurement substrate.

The processing gas may be HMDS gas.

The ion sensor may be provided on one half surface of the measurement substrate, and the wind speed sensor may be provided on the other half surface.

A gas flow passage through which gas flows may be formed inside the ion sensor, and a current collecting electrode for collecting ions may be provided inside the gas flow passage.

The gas flow passage has a straight portion extending linearly and a bent portion connected to the straight portion, and the current collecting electrode may be provided at the bent portion.

The current collecting electrode may be provided so as to cover the inner surface of the gas flow passage.

The present invention from another viewpoint is a measurement substrate used in the substrate processing apparatus, and is characterized by having the ion sensor and the wind speed sensor.

According to the present invention, the number of ions can be measured using an ion sensor, which is a simple device, and the concentration of the processing gas can be appropriately measured based on the number of ions to be measured. By appropriately controlling the concentration of the processing gas in this way, lot defects can be suppressed and the yield of the product can be improved.

It is a top view which shows the outline of the structure of the substrate processing system provided with the hydrophobizing treatment apparatus which concerns on this embodiment. It is a front view which shows the outline of the structure of the substrate processing system which concerns on this Embodiment. It is a back view which shows the outline of the structure of the substrate processing system which concerns on this embodiment. It is a vertical cross-sectional view which shows the outline of the structure of the hydrophobizing treatment apparatus which concerns on this embodiment. It is a top view which shows the outline of the structure of the hydrophobizing treatment apparatus which concerns on this embodiment. It is a vertical cross-sectional view which shows the outline of the internal structure of the ion sensor which concerns on this embodiment. It is a graph which shows the time-series change of the number of ions measured by an ion sensor. It is a vertical cross-sectional view which shows the outline of the structure of the hydrophobizing treatment apparatus which concerns on another embodiment. It is a top view which shows the outline of the structure of the hydrophobizing treatment apparatus which concerns on another embodiment. It is a vertical cross-sectional view which shows the outline of the internal structure of the ion sensor which concerns on other embodiment. It is a vertical cross-sectional view which shows the outline of the internal structure of the ion sensor which concerns on other embodiment. It is a vertical cross-sectional view which shows the outline of the internal structure of the ion sensor which concerns on other embodiment. It is a top view which shows the outline of the structure of the measurement wafer provided with the ion sensor which concerns on another embodiment. It is a top view which shows the outline of the structure of the measurement wafer provided with the ion sensor which concerns on another embodiment. It is a top view which shows the outline of the structure of the measurement wafer provided with the ion sensor which concerns on another embodiment.

Hereinafter, embodiments of the present invention will be described. In the present specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Board processing system>
First, the configuration of the substrate processing system including the hydrophobic treatment apparatus as the substrate processing apparatus according to the present embodiment will be described. FIG. 1 is a plan view schematically showing an outline of the configuration of the substrate processing system 1. 2 and 3 are a front view and a rear view, respectively, schematically showing an outline of the internal configuration of the substrate processing system 1. Then, in the substrate processing system 1, a predetermined process is performed on the wafer W as the substrate to be processed.

As shown in FIG. 1, the substrate processing system 1 includes a cassette station 10 for carrying in and out a cassette C accommodating a plurality of wafers W, and a processing station 11 provided with a plurality of various processing devices for performing predetermined processing on the wafers W. And the interface station 13 that transfers the wafer W to and from the exposure apparatus 12 adjacent to the processing station 11 are integrally connected.

The cassette station 10 is provided with a cassette mounting table 20. The cassette mounting table 20 is provided with a plurality of cassette mounting plates 21 on which the cassette C is mounted when the cassette C is carried in and out of the substrate processing system 1.

As shown in FIG. 1, the cassette station 10 is provided with a wafer transfer device 23 that is movable on a transfer path 22 extending in the X direction. The wafer transfer device 23 is movable in the vertical direction and around the vertical axis (θ direction), and is a transfer device for the cassette C on each cassette mounting plate 21 and the third block G3 of the processing station 11 described later. Wafer W can be conveyed between them.

The processing station 11 is provided with a plurality of, for example, four blocks provided with various devices, that is, first blocks G1 to fourth blocks G4. For example, a first block G1 is provided on the front side of the processing station 11 (negative direction in the X direction in FIG. 1), and on the back side of the processing station 11 (positive direction in the X direction in FIG. 1, upper side in the drawing). Is provided with a second block G2. Further, the third block G3 described above is provided on the cassette station 10 side of the processing station 11 (negative direction side in the Y direction in FIG. 1), and the interface station 13 side of the processing station 11 (positive in the Y direction in FIG. 1). A fourth block G4 is provided on the directional side).

For example, in the first block G1, as shown in FIG. 2, a plurality of liquid treatment devices, for example, a development processing device 30 for developing and processing wafer W, and an antireflection film (hereinafter, “lower antireflection”) under the resist film of wafer W. A lower antireflection film forming device 31 that forms a film), a resist coating device 32 that applies a resist solution to a wafer W to form a resist film, and an antireflection film (hereinafter, "upper antireflection") on an upper layer of a resist film of a wafer W. The upper antireflection film forming device 33 forming the "preventive film") is arranged in this order from the bottom.

For example, the developing processing device 30, the lower antireflection film forming device 31, the resist coating device 32, and the upper antireflection film forming device 33 are arranged side by side in the horizontal direction. The number and arrangement of the development processing device 30, the lower antireflection film forming device 31, the resist coating device 32, and the upper antireflection film forming device 33 can be arbitrarily selected.

In these developing processing devices 30, the lower antireflection film forming device 31, the resist coating device 32, and the upper antireflection film forming device 33, for example, spin coating is performed by applying a predetermined treatment liquid on the wafer W. In spin coating, for example, the processing liquid is discharged onto the wafer W from the coating nozzle, and the wafer W is rotated to diffuse the processing liquid on the surface of the wafer W.

For example, as shown in FIG. 3, the second block G2 includes a heat treatment apparatus 40 that performs heat treatment such as heating and cooling of the wafer W, and hydrophobization that performs hydrophobic treatment to improve the fixability between the resist liquid and the wafer W. The processing device 41 and the peripheral exposure device 42 for exposing the outer peripheral portion of the wafer W are provided side by side in the vertical direction and the horizontal direction. The number and arrangement of the heat treatment apparatus 40, the hydrophobizing treatment apparatus 41, and the peripheral exposure apparatus 42 can also be arbitrarily selected. The configuration of the hydrophobizing treatment device 41 will be described later.

For example, in the third block G3, a plurality of delivery devices 50, 51, 52, 53, 54, 55, and 56 are provided in order from the bottom. Further, in the fourth block G4, a plurality of delivery devices 60, 61, 62 are provided in order from the bottom.

As shown in FIG. 1, a wafer transfer region D is formed in a region surrounded by the first block G1 to the fourth block G4. In the wafer transfer region D, for example, a plurality of wafer transfer devices 70 having transfer arms that can move in the Y direction, the X direction, the θ direction, and the vertical direction are arranged. The wafer transfer device 70 moves in the wafer transfer area D and transfers the wafer W to predetermined devices in the surrounding first block G1, second block G2, third block G3, and fourth block G4. it can.

Further, as shown in FIG. 3, the wafer transfer region D is provided with a shuttle transfer device 80 that linearly conveys the wafer W between the third block G3 and the fourth block G4.

The shuttle transfer device 80 is linearly movable in the Y direction of FIG. 3, for example. The shuttle transfer device 80 moves in the Y direction while supporting the wafer W, and can transfer the wafer W between the transfer device 52 of the third block G3 and the transfer device 62 of the fourth block G4.

As shown in FIG. 1, a wafer transfer device 90 is provided next to the third block G3 on the positive direction side in the X direction. The wafer transfer device 90 has, for example, a transfer arm that can move in the X direction, the θ direction, and the vertical direction. The wafer transfer device 90 can move up and down while supporting the wafer W to transfer the wafer W to each transfer device in the third block G3.

The interface station 13 is provided with a wafer transfer device 100 and a transfer device 101. The wafer transfer device 100 has, for example, a transfer arm that can move in the Y direction, the θ direction, and the vertical direction. The wafer transfer device 100 can, for example, support the wafer W on a transfer arm and transfer the wafer W between each transfer device, the transfer device 101, and the exposure device 12 in the fourth block G4.

As shown in FIG. 1, the substrate processing system 1 described above is provided with a control unit 200. The control unit 200 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program that controls the processing of the wafer W in the substrate processing system 1. Further, the program storage unit also stores a program for controlling the operation of the drive system of the above-mentioned various processing devices and transfer devices to realize the hydrophobizing treatment described later in the substrate processing system 1. The program is recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnet optical desk (MO), or memory card. It may be the one installed in the control unit 200 from the storage medium.

<2. Hydrophobization treatment equipment>
Next, the configuration of the above-mentioned hydrophobizing treatment device 41 will be described. FIG. 4 is a vertical cross-sectional view schematically showing an outline of the configuration of the hydrophobizing treatment device 41. FIG. 5 is a plan view schematically showing an outline of the configuration of the hydrophobizing treatment device 41.

The hydrophobization treatment device 41 has a bottomed substantially U-shaped processing container 300 that houses the wafer W and has an opening at the top, and a lid 301 that covers the opening of the processing container 300. A mounting table 302 on which the wafer W is mounted is provided on the upper portion of the bottom surface of the processing container 300. A heater 303 for heating the wafer W is provided inside the mounting table 302.

Below the mounting table 302, an elevating pin 304 for supporting and elevating the wafer W from below is provided. The elevating pin 304 can be moved up and down by the elevating drive unit 305. The mounting table 302 and the processing container 300 are formed with through holes 306 penetrating in the thickness direction, and the elevating pin 304 is adapted to insert the through holes 306.

The lid 301 includes a horizontal top plate 310 and side plates 311 extending vertically downward from the outer peripheral edge of the top plate 310. The lower end portion 311a of the side plate 311 faces the upper end portion 300a of the processing container 300, and the processing space A is formed in the region surrounded by the processing container 300 and the lid 301.

The lid 301 includes an elevating mechanism 312 that moves the lid 301 up and down relative to the processing container 300. The position of the lid 301 in the height direction with respect to the processing container 300 so that a predetermined gap G is formed between the lower end 311a of the side plate 311 and the upper end 300a of the processing container 300 by the elevating mechanism 312. Has been adjusted.

The lid 301 is provided with a gas supply unit 320 that supplies the processing gas and the purge gas to the upper surface of the wafer W inside the processing container 300. In the gas supply unit 320, a gas supply port 321 is formed on the lower surface of the central portion of the lid 301. A gas flow path 322 formed inside the lid 301 communicates with the gas supply port 321.

A gas supply pipe 323 is connected to the gas flow path 322. The HMDS gas supply pipe 324 and the nitrogen gas supply pipe 325 are further connected to the gas supply pipe 323. The HMDS gas supply pipe 324 is connected to the HMDS gas supply source 326 that supplies the HMDS gas as a processing gas. Further, the HMDS gas supply pipe 324 is provided with a valve 327 that controls the flow of the HMDS gas. A nitrogen gas supply source 328 for supplying nitrogen gas as a purge gas is connected to the nitrogen gas supply pipe 325. Further, the nitrogen gas supply pipe 325 is provided with a regulator 329 for pumping nitrogen gas and a valve 330 for controlling the flow of nitrogen gas in this order from the nitrogen gas supply source 328 side. Then, the valves 327 and 330 can alternately switch the gas supplied to the wafer W between the HMDS gas and the nitrogen gas.

The HMDS liquid supply pipe 331 is connected to the HMDS gas supply source 326. An HMDS liquid tank 332 for storing a liquid HMDS liquid is further connected to the HMDS liquid supply pipe 331. Further, the HMDS liquid supply pipe 331 is provided with a valve 333 that controls the flow of the HMDS liquid. Then, the HMDS liquid supplied from the HMDS liquid supply pipe 331 is vaporized at the HMDS gas supply source 326 and changed to HMDS gas.

Further, the HMDS gas supply source 326 is connected to a nitrogen gas supply pipe 334 communicating with the nitrogen gas supply source 328 described above. Further, the nitrogen gas supply pipe 334 is provided with a regulator 335 for pumping nitrogen gas and a valve 336 for controlling the flow of nitrogen gas in this order from the nitrogen gas supply source 328 side. Then, the HMDS gas inside the HMDS gas supply source 326 is pumped into the processing container 300 by the nitrogen gas supplied from the nitrogen gas supply source 328.

The lid 301 is provided with an exhaust unit 340 that exhausts the inside of the processing container 300 (processing space A). In the exhaust portion 340, a plurality of exhaust ports 341 are formed at the lower end portion 311a of the side plate 311 of the lid body 301. The plurality of exhaust ports 341 are provided in an annular shape at equal intervals along the circumferential direction of the lower end portion 311a. An exhaust passage 342 formed inside the lid 301 communicates with each exhaust port 341.

An exhaust pipe 343 is connected to the exhaust passage 342. An exhaust device 344 such as a vacuum pump is further connected to the exhaust pipe 343. Further, the exhaust pipe 343 is provided with a valve 345 that controls the flow of gas.

The exhaust pipe 343 is provided with an ion sensor 346 between the exhaust device 344 and the valve 345. The ion sensor 346 can measure the number of ions (the number of ions per unit volume) in the gas flowing inside the exhaust pipe 343.

Specifically, as shown in FIG. 6, a gas flow passage 350 through which gas flows is formed inside the ion sensor 346. A repulsion electrode 351 is provided on the inner surface of the gas flow passage 350, and a current collector electrode 352 is provided inside the gas flow passage 350. Then, a voltage is applied to the repulsion electrode 351 so that the repulsion electrode 351 becomes an electrode having the same polarity as the ion. For example, when the ion is a cation, the repulsion electrode 351 is used as an anode. Then, the ions flow in the direction away from the repulsion electrode 351 and are collected by the current collector electrode 352. Then, by measuring the voltage of the current collecting electrode 352, the number of ions is measured from the relationship between the number of ions per unit volume and the voltage obtained in advance. In this way, the number of ions in the gas can be measured.

The purpose of providing the ion sensor 346 on the exhaust pipe 343 as described above is to measure the concentration of the HMDS gas by measuring the number of ions in the gas. Here, as a result of diligent studies by the present inventor, as shown in FIG. 7, for example, during the time T1 to T2, the hydrophobic treatment apparatus 41 is started, and the HMDS gas is inside the treatment space A by the gas supply unit 320. It was found that the number of ions (the number of ions per unit volume) measured by the ion sensor 346 increases when the inside of the processing space A is exhausted by the exhaust unit 340 while supplying the gas. In other words, as the concentration of HMDS gas increases, so does the number of ions. Therefore, it was found that there is a correlation between the concentration of HMDS gas and the number of ions. Then, in the present embodiment, the concentration of the HMDS gas can be calculated and monitored based on the number of ions measured by the ion sensor 346.

<3. Wafer processing>
Next, the wafer processing performed by using the substrate processing system 1 configured as described above will be described.

First, the cassette C containing the plurality of wafers W is carried into the cassette station 10 of the substrate processing system 1 and mounted on the cassette mounting plate 21. After that, each wafer W in the cassette C is sequentially taken out by the wafer transfer device 23 and transferred to the transfer device 53 of the third block G3 of the processing station 11.

Next, the wafer W is transferred by the wafer transfer device 70 to the heat treatment device 40 of the second block G2 and subjected to temperature control processing. After that, the wafer W is transported by the wafer transfer device 70 to, for example, the lower antireflection film forming device 31 of the first block G1, and the lower antireflection film is formed on the wafer W. After that, the wafer W is transferred to the heat treatment apparatus 40 of the second block G2 and heat-treated. After that, the wafer W is returned to the delivery device 53 of the third block G3.

Next, the wafer W is transferred by the wafer transfer device 90 to the transfer device 54 of the same third block G3. After that, the wafer W is transported by the wafer transfer device 70 to the hydrophobic treatment device 41 of the second block G2, and the hydrophobic treatment is performed. The hydrophobizing treatment in the hydrophobizing treatment apparatus 41 will be described later.

After that, the wafer W is transferred to the resist coating device 32 by the wafer transfer device 70, and a resist film is formed on the wafer W. After that, the wafer W is transferred to the heat treatment device 40 by the wafer transfer device 70 and prebaked. After that, the wafer W is transferred by the wafer transfer device 70 to the transfer device 55 of the third block G3.

Next, the wafer W is conveyed to the upper antireflection film forming device 33 by the wafer conveying device 70, and the upper antireflection film is formed on the wafer W. After that, the wafer W is transferred to the heat treatment device 40 by the wafer transfer device 70, heated, and temperature-controlled. After that, the wafer W is conveyed to the peripheral exposure apparatus 42 and subjected to peripheral exposure processing.

After that, the wafer W is transferred by the wafer transfer device 70 to the transfer device 56 of the third block G3.

Next, the wafer W is conveyed to the transfer device 52 by the wafer transfer device 90, and is transferred to the transfer device 62 of the fourth block G4 by the shuttle transfer device 80. After that, the wafer W is transported to the exposure device 12 by the wafer transfer device 100 of the interface station 13, and is exposed in a predetermined pattern.

Next, the wafer W is transferred by the wafer transfer device 100 to the transfer device 60 of the fourth block G4. After that, the wafer W is transferred to the heat treatment device 40 by the wafer transfer device 70, and is baked after exposure. After that, the wafer W is conveyed to the developing processing apparatus 30 by the wafer conveying apparatus 70 and developed. After the development is completed, the wafer W is transported to the heat treatment device 40 by the wafer transfer device 90 and post-baked.

After that, the wafer W is transported by the wafer transfer device 70 to the transfer device 50 of the third block G3, and then is transferred to the cassette C of the predetermined cassette mounting plate 21 by the wafer transfer device 23 of the cassette station 10. In this way, a series of photolithography steps is completed.

<4. Hydrophobization treatment>
Next, the hydrophobizing treatment in the above-mentioned hydrophobizing treatment apparatus 41 will be described. In the hydrophobizing treatment, the lid 301 is raised to a predetermined position by the elevating mechanism 312. Then, the wafer W is carried in from between the processing container 300 and the lid 301, and the wafer W is placed on the mounting table 302.

Next, the lid 301 is lowered to a position where a predetermined gap G is formed between the lower end 311a of the lid 301 and the upper end 300a of the processing container 300 to form the processing space A.

Next, after the wafer W is heated to, for example, 90 ° C. to 150 ° C. by the heater 303, HMDS gas having a predetermined concentration is supplied from the HMDS gas supply source 326 through the gas supply port 321 of the gas supply unit 320 inside the processing space A. Is supplied at a predetermined flow rate. Further, the exhaust device 344 is started together with the supply of the HMDS gas, and the HMDS gas is exhausted from the exhaust port 341 of the exhaust unit 340 at a predetermined flow rate. As a result, the HMDS gas supplied from above the center of the wafer W flows above the wafer W so as to diffuse toward the outer peripheral edge of the wafer W. Then, the surface of the wafer W in contact with the HMDS gas is hydrophobized. Further, the HMDS gas diffused to the outer peripheral edge portion of the wafer W is exhausted from the exhaust port 341 of the exhaust portion 340 provided on the outer side of the wafer W.

During this hydrophobization process, the concentration of HMDS gas is measured by measuring the number of ions with the ion sensor 346. Here, conventionally, for example, the time for supplying the HMDS gas to the inside of the processing space A is a time obtained by accumulating the worst conditions evaluated in advance and further providing a margin. On the other hand, in the present embodiment, the supply time of the HMDS gas can be minimized by measuring and monitoring the concentration of the HMDS gas with the ion sensor 346. As a result, the throughput of wafer processing can be improved.

After supplying the HMDS gas for a predetermined time to hydrophobize the entire surface of the wafer W, the supply of the HMDS gas is stopped. Then, nitrogen gas is supplied from the nitrogen gas supply pipe 325 through the gas supply port 321 of the gas supply unit 320 at a predetermined flow rate to purge the HMDS gas remaining in the processing space A. Further, the exhaust device 344 is started together with the supply of the HMDS gas, and the HMDS gas is exhausted from the exhaust port 341 of the exhaust unit 340 at a predetermined flow rate.

At the time of this purging, the concentration of HMDS gas is measured by measuring the number of ions with the ion sensor 346. Here, conventionally, for example, the time for purging is a time obtained by accumulating the worst conditions evaluated in advance and further providing a margin. On the other hand, in the present embodiment, the time for performing this purging can be minimized by measuring and monitoring the concentration of the HMDS gas with the ion sensor 346. As a result, the throughput of wafer processing can be further improved.

After the purging inside the processing space A is completed, the exhaust device 344 is stopped. Next, the lid 301 is raised to a predetermined height by the elevating mechanism 312, and the wafer W for which the hydrophobization treatment has been completed is carried out of the processing container 300. In this way, the hydrophobizing treatment in the hydrophobizing treatment apparatus 41 is completed.

According to the above embodiment, the concentration of the HMDS gas can be measured and monitored by using an inexpensive and compact one such as the ion sensor 346. As a result, the hydrophobization treatment can be appropriately performed using the HMDS gas having an appropriate concentration, lot defects can be suppressed, and the yield of the product can be improved.

Further, as described above, the supply time of the HMDS gas in the hydrophobizing treatment can be minimized, and the purging time with nitrogen gas can be minimized, so that the throughput of the wafer processing can be improved. ..

Conventionally, a mass flow meter (not shown) is provided in a nitrogen gas supply pipe 334 connecting the HMDS gas supply source 326 and the nitrogen gas supply source 328, and the flow rate of nitrogen gas is measured by this mass flow meter. The concentration was estimated. However, this mass flow meter detects, for example, the case where the HMDS gas leaks from the processing container 300 and the concentration of the HMDS gas changes, or the case where the HMDS gas leaks from the gas supply pipe 323 and the concentration of the HMDS gas changes. I can't. In the present embodiment, such a change in the concentration of the HMDS gas can also be detected.

<5. Other embodiments>
Next, other embodiments of the present invention will be described.

<5-1. Hydrophobic treatment device of another embodiment>
In the above embodiment, the ion sensor 346 is provided in the exhaust pipe 343 of the exhaust unit 340, but the place where the ion sensor 346 is provided is not limited to this. For example, as shown in FIGS. 8 and 9, the ion sensor 346 may be provided on the downstream side of the exhaust device 344 in the exhaust pipe 343 of the exhaust unit 340. Further, the ion sensor 346 may be provided in the gas supply pipe 323 of the gas supply unit 320, or may be provided in the HMDS gas supply pipe 324. Further, although not shown, the ion sensor 346 may be provided inside the processing container 300.

In any case, the same effect as that of the above embodiment can be enjoyed, that is, by monitoring the concentration of HMDS gas using the ion sensor 346, the hydrophobizing treatment is appropriately performed and the yield of the product is improved. Can be made to. It is also possible to improve the throughput of wafer processing.

If the ion sensor 346 is provided in the gas supply unit 320, the HMDS gas before processing will be passed through the ion sensor 346, and the HMDS gas may be contaminated. Then, the hydrophobization treatment may not be performed properly. Therefore, in order to avoid the influence on the hydrophobic treatment in this way, it is more preferable that the ion sensor 346 is provided in the exhaust unit 340.

<5-2. Ion sensors of other embodiments>
In the above embodiment, the ion sensor 346 has a repulsion electrode 351 and a current collector electrode 352, but the configuration of the ion sensor 346 is not limited to this. For example, as shown in FIG. 10, the repulsion electrode 351 may be omitted. Since the HMDS gas is flammable, it is preferable that the ion sensor 346 is provided with explosion-proof measures. In the present embodiment, since the application of voltage can be avoided by omitting the repulsion electrode 351, the ion sensor 346 can be made explosion-proof.

Further, as shown in FIG. 11, the gas flow passage 350 has a straight portion 353 extending linearly and a bent portion 354 connected to the straight portion 353, and the current collecting electrode 352 is provided in the bent portion 354. You may. In such a case, the ions flowing linearly through the straight portion 353 collide with the current collecting electrode 352 of the bent portion 354 and are reliably collected. Therefore, it is possible to efficiently collect ions at the current collecting electrode 352 while making the ion sensor 346 explosion-proof.

Further, as shown in FIG. 12, the current collecting electrode 352 may be provided so as to cover the inner surface of the gas flow passage 350. Even in such a case, the ions collide with the current collecting electrode 352 and are surely collected. Therefore, it is possible to efficiently collect ions at the current collecting electrode 352 while making the ion sensor 346 explosion-proof.

<5-3. Wafers for measurement in other embodiments>
In the above embodiment, the ion sensor 346 is provided in the hydrophobizing treatment device 41, but may be provided in the measurement wafer T as the measurement substrate as shown in FIG. The measurement wafer T has the same shape as the wafer W.

A plurality of ion sensors 346, a connection board 400, and a wiring 401 connecting each ion sensor 346 and the connection board 400 are provided on the measurement wafer T. An analog board 403 is connected to the connection board 400 via a printed wiring board 402. The analog board 403 is further connected to a logger (not shown) or a control device (not shown). Then, the data measured by the ion sensor 346 is output to these loggers and control devices.

Here, conventionally, an inspection as to whether or not the hydrophobizing treatment is appropriately performed on the wafer W has been performed using, for example, a contact angle meter. However, this contact angle meter is expensive. Further, since the contact angle meter is provided outside the hydrophobizing treatment device 41, it is necessary to transport the hydrophobized wafer W to the contact angle meter for inspection, which is very troublesome.

In this regard, in the present embodiment, the measurement wafer T is transported to the inside of the hydrophobic treatment apparatus 41 to perform the hydrophobic treatment, and the concentration of HMDS on the measurement wafer T is determined by using a plurality of ion sensors 346. Can be measured. Therefore, it is possible to omit the inspection using the conventional contact angle meter and to inexpensively and simply inspect whether or not the hydrophobizing treatment is properly performed.

In the above embodiment, the data measured by the ion sensor 346 is output by wire, but may be output wirelessly. As shown in FIG. 14, a plurality of ion sensors 346, a measurement circuit 410, and a wiring 411 connecting each ion sensor 346 and the measurement circuit 410 are provided on the measurement wafer T. The measurement circuit 410 includes, for example, an analog circuit, a memory, a power supply, a wireless communication circuit, and the like. Then, the data measured by the measurement circuit 410 is wirelessly output from the measurement circuit 410 to the external control device 412, for example.

Even in such a case, the same effect as that of the above-described embodiment can be enjoyed, that is, it is possible to inexpensively and simply inspect whether or not the hydrophobization treatment is appropriately performed.

On the measurement wafer T of the above embodiment, in addition to the ion sensor 346, a wind speed sensor 420 for measuring the wind speed of the gas on the measurement wafer T may be provided as shown in FIG. In such a case, for example, in the measurement wafer T, a plurality of ion sensors 346 are provided on one half surface, and a plurality of wind speed sensors 420 are provided on the other half surface. A connection board 422 is connected to the wind speed sensor 420 via wiring 421. An analog board 424 is connected to the connection board 422 via a printed wiring board 423. The analog board 424 is connected to a logger (not shown) or a control device (not shown). Then, the data measured by the wind speed sensor 420 is output to these loggers and control devices.

As shown in FIG. 14, the data measured by the ion sensor 346 may be output wirelessly, and similarly, the data measured by the wind speed sensor 420 may be output wirelessly.

In such a case, for example, by inverting the measurement wafer T and measuring twice, the concentration of HDMS gas on the entire surface of the measurement wafer T can be measured by the ion sensor 346, and the measurement wafer T can be measured by the wind speed sensor 420. It is possible to measure the wind speed of the gas on the entire surface of the. Then, by measuring both the concentration of the HDMS gas and the wind speed of the gas in this way, it is possible to perform a more precise inspection as to whether or not the hydrophobization treatment is properly performed.

Further, a temperature sensor (not shown) for measuring the temperature of the measurement wafer T may be further provided on the measurement wafer T. That is, on the measurement wafer T, in addition to the ion sensor 346, a temperature sensor may be provided instead of the wind speed sensor 420, or both the wind speed sensor 420 and the temperature sensor may be provided. In such a case, by also measuring the temperature of the measuring wafer T, it is possible to more precisely inspect whether or not the hydrophobization treatment is properly performed.

In the above embodiment, the case of measuring the concentration of HMDS as the processing gas has been described, but the present invention is also applicable to the case of measuring the concentration of another processing gas if the processing gas contains ions. Can be done. In addition, the other treatment gas can be used to appropriately perform treatments other than the hydrophobization treatment.

Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the ideas described in the claims, which naturally belong to the technical scope of the present invention. It is understood as a thing.

1 Substrate processing system 41 Hydrophobicization treatment device 200 Control unit 300 Processing container 301 Lid 320 Gas supply unit 340 Exhaust unit 346 Ion sensor 350 Gas flow passage 351 Repulsion electrode 352 Current collection electrode 353 Straight part 354 Bending part 420 Wind speed sensor A processing Space W wafer T measurement wafer

Claims (7)

A substrate processing device that processes a substrate to be processed using a processing gas containing ions.
A processing container that houses the substrate to be processed and
A gas supply unit that supplies processing gas to the inside of the processing container,
An exhaust unit that exhausts the inside of the processing container and
An ion sensor provided on a measurement substrate having the same shape as the substrate to be processed and measuring the number of the ions contained in the gas inside the processing container.
A substrate processing apparatus comprising the ion sensor and a wind speed sensor provided on the measurement substrate and measuring the wind speed above the measurement substrate. The substrate processing apparatus according to claim 1, wherein the processing gas is an HMDS gas. The substrate processing apparatus according to claim 1 or 2, wherein the ion sensor is provided on one half surface of the measurement substrate, and the wind speed sensor is provided on the other half surface. A gas flow path through which gas flows is formed inside the ion sensor.
The substrate processing apparatus according to any one of claims 1 to 3, wherein a current collecting electrode for collecting ions is provided inside the gas flow passage. The gas flow passage has a straight portion extending linearly and a bent portion connected to the straight portion.
The substrate processing apparatus according to claim 4, wherein the current collecting electrode is provided at a bent portion. The substrate processing apparatus according to claim 4, wherein the current collecting electrode is provided so as to cover the inner side surface of the gas flow passage. A measuring substrate used in the substrate processing apparatus according to any one of claims 1 to 6, characterized by having the ion sensor and the wind speed sensor.

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