JPH0587175B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is applicable to a substrate such as a semiconductor wafer (hereinafter simply referred to as a substrate) in which a coating material is applied in multiple layers. The present invention relates to a substrate processing apparatus that performs similar types of processing.

<Prior Art> Generally, when applying a coating material onto a substrate, a process may be adopted in which the coating process is repeated to apply multiple layers of the coating material onto the substrate.

Conventionally, there are the following substrate processing apparatuses that perform the same type of processing on the same substrate multiple times.

For example, the substrate processing apparatus shown in FIG. 8 includes a loader 1 that sequentially supplies substrates stored in a cassette (not shown) one by one, and a liquid coating material applied to the substrates supplied from the loader 1 under predetermined conditions. a coater 2 as a first processing section that performs spin coating, an oven 3 as a second processing section that heats and dries the substrate coated with the coating material, and an unloader 4 that sequentially stores the heat-treated substrates in a cassette. are arranged in tandem, and the respective units are connected in a loop shape by a substrate transport mechanism 5 such as an air track, a belt track, or a robot arm.

According to this apparatus, the substrates are connected in a loop so that the substrates are unloaded from the cassette of the unloader 4 containing the group of substrates that have undergone the first coating process, and then the second coating process is performed again. By rotating the substrate between each unit, multiple layers of coating material are applied onto the substrate.

<Problems to be Solved by the Invention> However, the above-described conventional device has the following problems.

When automating the process, if the device performs the process once, it is easy to manage it by simply storing the processed substrates in the unloader one after another. However, if the same type of processing is performed on the same substrate On the other hand, in the above-mentioned apparatus that performs processing repeatedly, it is necessary to manage at what point the substrate is stored in the unloader at the end of the processing. Regarding this point, the following method is disclosed in Japanese Patent Publication No. 18855/1985 (title of the invention: ``Method for manufacturing a semiconductor device''). This method requires that each substrate be given processing conditions (e.g.
At least one unloader is attached to each processing device in series, and a mark pattern such as a bar code is attached to record the set number of repetition processing, etc.), and at least one unloader is attached in series between each processing device and the attached unloader. The mark pattern is identified by the mark pattern, and the progress of processing is managed based on the individual mark pattern.

Although the above method is an excellent method, it is troublesome in that it requires the work of applying a mark pattern to each substrate.

The present invention was made to solve these problems, and it is possible to easily change the number of treatments when performing the same type of treatment on a substrate multiple times. , mark on the board
It is an object of the present invention to provide a substrate processing apparatus that does not require patterning.

<Means for Solving the Problems> In order to achieve the above object, the present invention has the following configuration.

That is, in the present invention, a loader that sequentially supplies substrates, a processing section that performs required processing on the substrates supplied from the loader, and an unloader that sequentially stores the processed substrates form a substrate transport mechanism. The substrate processing apparatus is connected in a loop through a substrate processing apparatus, and includes a state (through state) in which a substrate transported from the processing section passes through or bypasses the unloader and loader and sends it to the processing section; a switching transport mechanism configured to be able to switch between a state (store state) in which the board transported from
processing number setting means for setting the number of processing times; processing completion signal detection means for detecting processing completion and outputting a processing completion signal each time the processing is performed by the processing section; and the setting processing for each board. The number of times is compared with the cumulative number of outputs of the processing completion signal of each board, and if the cumulative number of outputs of the processing completion signal is smaller than the set processing number, the switching conveyance mechanism is put into the through state, and both the number of times are output. The present invention is characterized by comprising: a control means for controlling the switching transport mechanism so as to place the switching transport mechanism in a store state and storing the processed substrate in the unloader when a match is found.

<Effect> The effects of the present invention are as follows.

First, the number of processing repetitions (set processing number) required for each substrate is set by the processing number setting means. Each time the processing section performs the required processing on each substrate sequentially supplied from the loader, a processing completion signal for each substrate is detected by the processing completion signal detection means. The control means compares the set number of times of processing and the cumulative number of times of outputting the processing completion signal for each board. If the cumulative number of times the processing completion signal is output is smaller than the set number of processing times, the control means sets the switching conveyance mechanism to the through state. Then,
The substrate transported from the processing section is again supplied to the same processing section via the switching transport mechanism and subjected to the same type of processing again. When the cumulative number of outputs of the processing completion signal and the set number of processing match, the control means sets the switching conveyance mechanism to the store state.
As a result, each substrate that has been processed a preset number of times is sequentially stored in the unloader.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic block diagram showing the configuration of a control system of a substrate processing apparatus according to an embodiment of the present invention, and FIG.
The figure shows the layout of each part mechanism.

First, referring to FIG. 2, the outline of each part mechanism in this device will be explained.

The substrate processing apparatus according to this embodiment includes a loader 11 that sequentially supplies substrates stored in a cassette, and a coater 12 as a first processing section that applies coating material to the substrates supplied from the loader 11.
and an oven 13 as a second processing section that heats and dries the substrate coated with the coating material.
, a buffer 14, and an unloader 15 that sequentially stores coated substrates in a cassette.
are connected in a loop shape via direction changing conveyors 16 ₁ , 16 ₂ as substrate transport mechanisms.

The buffer 14 is used to temporarily store processed substrates when they are discharged from the oven 13 before the loader 11 has finished feeding all the substrates. It has a substrate storage mechanism similar to that of the unloader 15.

Further, in this embodiment, from the oven 13 to the buffer 14 and from the buffer 14 to the unloader 15
to, unloader 15 to loader 11, loader 1
As a substrate conveyance mechanism from 1 to the direction change conveyor 16 ₁ , an arm-type substrate transfer device, which will be described later, is used. However, the substrate transport mechanism used in the present invention is not limited to these, and for example, a belt-type substrate transport mechanism or a mechanism that transports the substrate by air injection may be employed.

FIG. 3 is a perspective view showing the configuration of a substrate transfer device applied to the loader 11, buffer 14, and unloader 15.

On both sides of the substrate transfer device 21 provided on the substrate transfer path A, an arm-type storage-side substrate transfer mechanism 22 and an ejection-side substrate transfer mechanism 23 are provided, respectively. Here, the storage-side substrate transport mechanism 22 and the take-out-side substrate transport mechanism 23 provided in the loader 11 and the unloader 15 constitute a switching transport mechanism in the present invention in conjunction with the substrate transfer device 21.

The substrate transfer device 21 is configured as follows.

That is, a support frame 26 is slidably fitted into a pair of guide rods 25 erected on a base 24, and a threaded rod 2 is attached to the base end of the support frame 26.
7 are screwed together, and this threaded rod 27 is driven by a motor 28 with a belt, thereby making the support frame 26 movable up and down. A top plate 30 is attached to the upper surface of the support frame 26 via a plurality of spacers 29. A cassette C for storing substrates W is detachably attached to this top plate 30. The gap between the support frame 26 and the top plate 30 forms a tunnel portion 31 for transferring the substrate W between the substrate transport mechanisms 22 and 23, which will be described later. In this tunnel portion 31, a substrate mounting member (not shown) that can be raised and lowered is provided to assist in transferring the substrate W between the substrate transport mechanisms 22 and 23.

The storage side substrate transfer mechanism 22 and the takeout side substrate transfer mechanism 23 each have a first arm 33 ₁ , a transfer motor 32 ₁ , 32 ₂ fixed to a base 24 ,
One end side of 33 ₂ is attached to the first arm 33 1 , 33 2 so as to be freely rotatable, and the first arm 33 ₁ , 33 ₂ is attached to the other end side of the first arm 33 ₁ , 33 ₂ via a regulating belt.
the second arm 34 ₁ so as to rotate in the opposite direction;
34 ₂ is attached. Second arm 34 ₁ ,
Suction ports 35 ₁ and 35 ₂ for suctioning and holding the back surface of the substrate W are formed at the tip of the substrate 34 ₂ .

Storage side substrate transfer mechanism 2 via tunnel section 31
The transfer operation of the substrate W from 2 to the take-out side substrate transport mechanism 23 (hereinafter, such a state of transfer operation of the substrate W will be referred to as a through state) is performed as follows.

First, the suction port 35 ₁ of the storage side substrate transport mechanism 22
While holding the substrate W by suction, the electric transport motor 32 ₁ is driven and rotated to move the second arm 34 ₁ to the first
The second arm 34 ₁ is bent and extended relative to the arm 33 _{1 .}
The substrate W is inserted into the tunnel portion 31 by horizontally moving the tip thereof. This substrate W is delivered to a substrate placement member within the tunnel section 31. Next, the transfer transmission motor 32 ₂ of the take-out side substrate transfer mechanism 23 is driven, and the second arm 34 ₂ is transferred to the tunnel portion 3 .
1.

After the substrate W placed on the substrate platform is sucked and held by the suction port 35 ₂ , the substrate W is taken out from the tunnel section 31 by rotating the transport electric motor 32 ₂ in the reverse direction.

Next, the operation for storing or removing the substrates W from the cassette C will be explained.

In this case, the motor 28 is rotationally driven to move the support frame 26 downward from the position shown in FIG. When storing the substrates W in the cassette C (hereinafter, such an operating state will be referred to as the store state), the storage side substrate transport mechanism 23 operates in the same manner as in the through state described above, and the substrates are placed in the predetermined groove of the cassette C. The substrate W is stored in the. When taking out the substrate W from the cassette C, the take-out side substrate transport mechanism 22 is driven in the same manner as in the through state described above.

Next, the configuration of the control system of this embodiment will be explained with reference to FIG.

In the figure, SW1 is a loop number setting switch serving as a processing number setting means for setting how many times the coating material is repeatedly applied to the substrate W, SW2 is a start switch that commands the start of loading the substrate,
SW3 is a loading end switch that commands the end of board loading.

Light emitting diode 41 and phototransistor 4
2 constitutes a substrate detector 43 that detects the substrate W. The substrate detector 43 is attached to the buffer 14, for example, and detects the substrate W that has been coated by the coater 12 and heated by the oven 13. The detection signal of the board detector 43 is transmitted to the parallel input/output interface 44.
The data is taken into the CPU 45 via. The substrate detector 43 corresponds to processing completion signal detection means in the present invention.

Furthermore, the CPU 45 corresponds to the control means in the present invention, and the parallel input/output interface 4
4, the loader 11, coater 12, oven 13, buffer 14, unloader 15, and each of the above-mentioned transport mechanisms are controlled. In addition, the code 46
is a ROM in which a control program is stored, 47
As shown in FIG. 4, the set processing number DS input from the loop number setting switch SW1 and the cumulative output number DP of the processing completion signal given from the CPU 45 are determined for each board (in this example) as described later. This is an identification (ID) memory that is stored in association with the boards No. 1 to No. 25 that make up one lot.

Next, the operation of the embodiment will be described with reference to the operation flowcharts shown in FIGS. 5 and 6.

First, with reference to FIG. 5, the operation of the loader 11 will be described.

When the start switch SW2 is turned on (step S1), the loader 11 is driven and the first substrate is taken out from the cassette (step S2). Then, read the setting value (in this example, "3") by the loop number setting switch SW1, and set the value corresponding to the first board as shown in Figure 4.
In the memory area set in the ID memory 47, 3 is set as the set number of processing times DS (that is, the coating process is performed three times), and 0 (unprocessed) is set as the cumulative number of output times DP of the processing completion signal ( Step S3).

Next, based on the state of the input switch SW3, it is determined whether or not loading of all boards from the loader 11 has been completed (step S4), and if loading has not been completed, the acceptance of boards from the unloader 15 is prohibited. (Step S5) Return to step S2, take out the next (second) board from the loader 11, and store it in the memory area of that board. Set DS=3, DP=0. Thereafter, the same process is repeated for each substrate making up one lot.

When the loading of one lot of substrates is completed, the loading end switch SW3 is pressed by the operator.
In addition, when processing each cassette as one lot, the loader 11 is turned off by the loading end switch.
If SW3 is attached, when loading one cassette of boards is completed, the loading end switch SW3 will be activated automatically.
may be set to be in the ON state. For this purpose, for example, the loader 11 is operated so that the substrates in the cassette C are sequentially loaded from the bottom, and a position sensor is attached to detect when the support frame 26 has reached the lowest position. may be used as the input/end switch SW3.
When processing multiple cassettes as one lot, a subtraction counter is attached to sequentially subtract the number of cassettes into which substrates have been loaded from the number of cassettes set and input in advance, and when the substrates in all cassettes have been loaded. Then, the input/end switch SW3 may be operated.

When it is determined that the loading end switch SW3 is in the ON state (step S4), the process proceeds to step S6, where the loader 11 is set to the through state and stands by.

The above-mentioned through state continues until the processing of all the substrates is completed (step S7), and when the processing of all the substrates is completed, the loader 11 returns to the initial state (return to origin) in which the substrates can be taken out (step S8). .

Next, the processing operation regarding the buffer 14 will be explained with reference to FIG.

When inputting the substrate is started, the CPU 45 monitors whether the substrate has been detected based on the output signal from the substrate detector 43, that is, whether the coating process and heating process of the substrate have been completed. (Step S11). When a board is detected, the set processing number DS and the cumulative output number DP of the processing completion signal for that board are read from the ID memory 47 (step S12), and "1" is added to the value of the cumulative output number. The added value is replaced with the original DP value (step S13). Then, it is determined whether the newly replaced DP value matches the set number of processing times DS (step S14).

Note that reading the set processing number DS and the cumulative output number DP of processing completion signals in step S12 is as follows:
It is necessary to read out the DS and DP corresponding to each board, but in order to do this, the memory area to be read in the ID memory 47 is shifted so that the next memory area is read out one by one each time it is read out. good. This is because substrates are transported in a first-in first-out manner in the substrate processing apparatuses connected in a loop. Note that the replacement of the DP value in step S13 and the determination of whether the DP value matches the DS in step S14 are also performed by sequentially shifting the memory areas one by one.

If the DP value does not match the DS value, i.e.
If the DP value is smaller than the DS value, it means that the substrate has not been processed the required number of times, so the process advances to step S15 and the loader 11 and unloader 15 are set to the through state.

If previously processed substrates are temporarily stored in the buffer 14, they are stored and discharged on a first-in, first-out basis. On the other hand, Batsuhua 14
If no board is stored in buffer 1,
Eject the board that has reached step 4 (step 4).
S16).

The substrate discharged from the buffer 14 passes through the buffer 14 and the loader 11 which are in the through state, and is again processed by the coater 12 and oven 13 (step S17).

Then, by repeating the procedure from step S11 to step S13, the cumulative number of outputs DP of the processing completion signal is incremented by "1" each time each board is processed. If it is determined in step S14 that the total number of outputs of the processing completion signal DP matches the set number of processing times DS, the process proceeds to step S18, where the unloader 15 is set to the store state. Subsequently, the substrates are discharged from the buffer 14 to the unloader 15 on a first-in, first-out basis. Then, based on whether the DP values of all the boards in the ID memory 47 have become equal to the DS value, it is determined whether the processing of all the boards has been completed (step
S20) If all the processing has not been completed, the process returns to step S11, and if all the processing has been completed, the operation ends.

In the above-described embodiment, the switching transport mechanism is the storage-side substrate transport mechanism 22 and the take-out-side substrate transport mechanism 2 attached to the substrate delivery device 21.
For example, as shown in FIG. 7, a bypass conveyance path 50 is provided to bypass the unloader 15 and loader 11, and in the through state, the substrate conveyed from the oven 13 is The substrate may be transported to the coater 12 via the bypass transport path 50, and when in the store state, the bypass transport path 50 may be disconnected and the substrate may be stored in the unloader 15.

Further, in the embodiment, the processing section is composed of the coater 12 and the oven 13, but it goes without saying that it may be composed of other processing apparatuses such as a substrate cleaning processing apparatus.

Furthermore, the buffer 14 included in the device of the embodiment
This is provided as a safety measure for adjusting the operating time of each mechanical section and for unexpected failure, and is therefore not necessarily required in the present invention.

<Effects of the Invention> As is clear from the above description, according to the substrate processing apparatus according to the present invention, the loader, the processing section, and the unloader are connected in a loop shape via the substrate transport mechanism,
If the total number of times the board processing completion signal is output is less than the set number of processing times, the board is reprocessed by passing or bypassing the unloader and loader, and when the total number of times the processing completion signal is output matches the number of set processing times. Since the substrate is stored in the unloader, it is possible to automatically perform the same type of processing on the substrate multiple times. Further, by appropriately changing the set number of times of processing, the number of repetitions of substrate processing can be easily changed.

[Brief explanation of drawings]

1 to 6 are explanatory diagrams of one embodiment of the present invention, in which FIG. 1 is a schematic block diagram of its control system, FIG. 2 is a block diagram showing an example of the arrangement of each part,
Fig. 3 is a perspective view of a substrate transfer device commonly used in loaders, unloaders, and buffers and a substrate transport mechanism attached thereto, Fig. 4 is an explanatory diagram of the ID memory included in the control system, and Fig. 5 is an illustration of the ID memory included in the control system. An operational flowchart regarding the loader, and FIG. 6 is an operational flowchart regarding the buffer. Further, FIG. 7 is an explanatory diagram of another embodiment of the switching conveyance mechanism. FIG. 8 is a schematic block diagram of a conventional substrate processing apparatus. 11...Loader, 12...Coater, 13...Oven, 14...Buffer, 15...Unloader, 16 ₁ , 16 ₂ ...Direction change conveyor, 21
...Substrate transfer device, 22...Storing side substrate transport mechanism, 23...Takeout side substrate transport mechanism, 43...
...Substrate detector, 45...CPU, 47...ID memory, 50...Bypass transport path, SW1...Loop number setting switch.

Claims (1)

[Claims] 1. A loader that sequentially supplies substrates, a processing section that performs required processing on the substrates supplied from the loader,
An unloader that sequentially stores the processed substrates is a substrate processing apparatus connected in a loop via a substrate transport mechanism, and the substrates transported from the processing section are passed through the unloader and the loader. or a switching transport mechanism configured to be able to switch between a state where the substrates are bypassed and sent to the processing section (through state) and a state where the substrates transported from the processing section are stored in the unloader (store state); Number of processing repetitions required for the board (set processing number)
processing number setting means for setting the number of processing times; processing completion signal detection means for detecting processing completion and outputting a processing completion signal each time the processing is performed by the processing section; and the setting processing for each board. The number of times is compared with the cumulative number of outputs of processing completion signals for each board, and if the cumulative number of outputs of processing completion signals is smaller than the set number of processing, the switching transfer mechanism is put into a through state, and the two numbers match. a control means for controlling the switching and transporting mechanism so as to place the switching and transporting mechanism in a store state and storing the processed substrate in the unloader when the switching and transporting mechanism is stored in the unloader.