JP2002182729A - Production control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production control method for previously avoiding a trouble for setting the many flows of works based on various pieces of information such as a corresponding relation between devices and load prediction, and realizing both of leveling (dispersing) device load and high yield. SOLUTION: A processor used in a processing process (b) where a processor which can be processed in accordance with the corresponding relation with the processors A1 to A3 of the other device group A in the other processing process (a) is limited is designated based on processing history showing in which processor the work is processed in a previous process (a) and on the previously generated corresponding relation when the work reaches the processing process (b). The work is processed in a designated processor B1. When the processing of the work is completed, it is recorded that the work has been processed in the processor B1 as processing history.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work which is sent between processing steps by designating which processing apparatus should be selected from a group of apparatuses having the same function in each processing step to perform the processing. The present invention relates to a production control method for controlling a way of sending (flowing) between the respective processing steps.

[0002]

2. Description of the Related Art For example, in the production of semiconductor devices, when a job shop type production line in which a plurality of processing apparatuses having the same function are arranged together and arranged as a same apparatus group is configured, a processing line in the apparatus group in a previous process is used. When processing is performed using a certain processing apparatus, in a subsequent process, a predetermined yield is obtained unless a specific processing apparatus corresponding to the processing apparatus used in the previous process is selected from a group of apparatuses in the subsequent process. You can't expect that.

[0003] For example, in a certain process a, when the work of the lot number 1 is processed by the processing apparatus A1 in the apparatus group A including three processing apparatuses A1, A2, and A3 having the same function, as shown in FIG. Depending on the correspondence (compatibility) between the devices, the devices that can be used in the next step b may be limited. In this case, the work of lot number 1
Since the processing apparatus A1 is used in step b, the processing can be performed only in the processing apparatus B1 or B3 indicated by a circle in FIG. 3 corresponding to the processing apparatus A1 in step b.

[0004] Such limitation of usable devices is caused by variations in performance among the processing devices. All devices in each device group have the same kind of function and perform the same processing, but there is a slight difference in performance. For example, when the apparatus group A is considered, there is a slight difference in finish (quality) between the work processed by the processing apparatus A1 and the work processed by the processing apparatus A2. At this stage, even if the difference is small, the processing is repeated in the apparatus groups B, C,.
Regarding the finished condition of the final workpiece, the variation increases depending on the combination of the processing apparatuses that have been subjected to the processing between the respective processing steps, and some of them may be defective. Therefore, it is necessary to optimally set the combination of the equipment used between the processing steps so as not to produce a defective product. When the workpiece is processed by the apparatus shown in the figure, the yield is remarkably deteriorated.

[0005]

Therefore, conventionally, a work flow (a processing interval between processing steps) in which processing apparatuses to be used in each processing step are determined in a limited manner in consideration of the correspondence between the processing apparatuses in advance. Of the work flow). For example, as shown in FIG. 5, each of the steps a to d includes an apparatus group (A in the step a) including four similar apparatuses (for example, the processing apparatuses A1 to A4 in the step a). The flow of the work between the steps is set in advance according to the correspondence between the apparatuses. For example, in this case, as the process proceeds from a to d, the work flows through the processing devices A1, B2, C3, and D2, the flow f2 flows through the processing devices A2, B3, C1, and D2, and the processing device. A flow f3 flowing through A3, B1, C2, D3;
Four flows of the processing devices A4, B4, C4, and D4 and the flowing flow f4 are set in advance.

[0006] Even if the work is equally input to the processing apparatuses A1 to A4 in the process a so as to distribute the load applied between the apparatuses, the load is distributed at this stage. In a process such as a difference in processing time between apparatuses or a process such as a lens reduction projection exposure process that returns from the process d or a subsequent process to the process a and repeats a similar process, the work is performed in each process step. As you proceed, or as you repeat each processing step,
The work is concentrated on a certain processing apparatus, and the load on the processing apparatus increases. Therefore, when creating a work flow, it is necessary to consider such load prediction, and also to consider the work input amount and timing for each of the flows f1 to f4, based on various information. Detailed management, including the setting of the flow, was required and complications could not be avoided.

In the prior art, for example, the work put into the flow f1 flows only to the processing devices A1, B2, C3, and D2, so that a large load is applied to the processing device B2. When the processing apparatus A1 is compatible with the processing apparatus B1, the work is transferred to the processing apparatus A.
I want to disperse from 1 to B1, but I can't do this. Further, for example, when the processing device B1 breaks down, the work cannot flow in the flow f1 including the processing device B1.
As described above, conventionally, it has been difficult to sufficiently exert the maximum production capacity of the semiconductor device production line.

The present invention has been made in view of the above problems, and avoids the trouble of setting a number of work flows in advance based on various information such as correspondence between devices and load prediction.
It is an object of the present invention to provide a production control method for realizing a balance between leveling (dispersing) device load and high yield.

[0009]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, one of a plurality of processing units having the same function is selected from a group of processing units. This is a production control method for performing processing in one processing step of a work, and the processing reaches a processing step in which processing apparatuses that can perform processing in other processing steps are limited according to a correspondence relationship with a processing apparatus in another apparatus group. And, based on the processing history of which processing apparatus the workpiece has been processed in the previous process and the correspondence created in advance, the processing apparatus to be used in this processing step is specified, and the specified processing apparatus When the processing of the work is completed and the processing of the work is completed, the fact that the work has been processed by this processing device is recorded as a processing history. In other words, rather than preliminarily limiting the route through which the work flows through each processing step, the use of the processing apparatus at the stage where the usable processing apparatuses corresponding to the processing apparatuses used in the preceding processing step are limited is reached. Selectivity is provided so that possible processing units can be selected.

According to a second aspect of the present invention, when a processing device is specified, if there are two or more options of the processing device, the processing device with less load is specified. In other words, avoiding the use of equipment that concentrates workpieces to be processed or equipment that is out of order (in this case, it is assumed that the load is infinitely applied), the workpieces can be efficiently transferred between processing steps. Flow can increase productivity.

[0011]

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

The production control method according to this embodiment includes a host computer (server) in which basic software (OS: Operating System), software for communication, a relational database system for managing various data, and the like are incorporated. A production control method according to the present embodiment is provided by using a client-server type computer system which is generally constructed at present, comprising a terminal device (client computer) connected to this by a network. A process management system for semiconductor device production incorporating a program for realizing the above is installed. The terminal devices are arranged in various parts of the production line, and the worker controls the flow of the work by using the terminal devices to confirm the instruction of the processing operation, start and end the operation, and the like.

Next, a production control method according to the present embodiment will be described with reference to the flow chart shown in FIG.

First, for example, it is assumed that the work 1 of the lot number 1 composed of 25 semiconductor wafers has been processed in the processing apparatus A1 in the process a shown in FIG. (Step S1). In addition,
At the stage when the processing by the processing device A1 is completed, the lot number 1
The processing history indicating that the work 1 has been processed by the processing apparatus A1 is recorded in the history table of the host computer from the terminal device. In FIG. 2, the device group A in the process a includes, for example, three processing devices A1 to A3 having the same function (the functions are different from those of the other device groups B and C). B is composed of three processing devices B1 to B3 having the same kind of function, and the device group C in the process c includes:
It comprises three processing devices C1 to C3 having the same kind of function.

Then, the operator confirms whether or not the process b is a process for limiting the use processing apparatus (step S2).

If the determination in step S2 is Yes, the terminal device accesses the database of the host computer to determine the past processing history of work 1 of lot number 1 (the processing device A1 was used in process a). History),
Further, the device correspondence table shown in FIG. 3 is checked (step S3).

According to the correspondence table between apparatuses shown in FIG.
The processing device compatible with (compatible with) the processing device A1 is B
Therefore, in this step b, the processing device B1 or B2 is selected for the work 1 of the lot number 1. That is, the work 1 which has already been processed by the processing apparatus A1 can be prevented from becoming defective if the processing is performed by the processing apparatus B1 or B2 in step b.

Then, the operator further designates, as a device to be used, a device having better conditions, that is, a device in which there is no failure, or a device in which works are not concentrated and no load is applied, for example, a processing device B1. Then, the processing of the work 1 is performed by the processing device B1 (step S5).

If the result of the determination in step S2 is No, an apparatus having good conditions is selected from the processing apparatuses B1 to B3 regardless of the correspondence with the processing apparatus A1.

When the processing of the work 1 in the processing device B1 is completed, the operator inputs the end of the processing from the terminal device, and further, the work 1 is processed as a processing history indicating which processing device was used in the process b. The device name or device ID (identifier) of B1 is recorded in the history table of the host computer (step S6). If the history is left every time the processing is performed by all the processing devices, the storage amount of the history data increases. Therefore, the processing history is stored in the processing device with limited use. Only the case is necessary.

Then, the work 1 reaches the next step c (step S7).

Then, also in the step c, the procedure of the steps S1 to S6 in the step b is repeated. In step S2 of this process c, if it is also determined as Yes, the past processing history of the work 1 (the history that the processing device B1 was used in the process b) and the inter-device correspondence table shown in FIG. To check. Then, according to the inter-apparatus correspondence table of FIG. 4, the processing apparatus that can cope with the processing apparatus B1 is C1 or C3. Therefore, in this step c, the processing apparatus C1 or C2 is selected for the work 1.

Further, the operator designates a device having better conditions, for example, a processing device C1 with less load as a device to be used.
Is performed.

When the processing of the work 1 in the processing device C1 is completed, the work 1 is moved to the processing device C1 in step c.
Is recorded in the history table of the host computer.

The work 2 (lot number 2) processed by the processing device A2 in the process a, and the work 3 (lot number 3) processed by the processing device A3 in the process a.
Also, the optimum processing device is selected in each of the steps b and c in the same flow as in the case of the work 1, and the processing is performed.

As described above, according to the present embodiment, the load on the processing apparatus can be distributed and each processing can be performed without performing a complicated setting work (how to flow between each step of the work) in advance. A high yield can be realized by suppressing the occurrence of defective products in consideration of the correspondence between the devices.

In the case of repeating the steps a to c many times, for example, in the processing using a lens reduction projection exposure apparatus (stepper), the processing of the work 1 is performed once, for example, in the flow of the processing apparatus A1, B1, C1. For example, since this is left as history data, the next time the work 1 arrives at the processing device A1, it is not necessary to make a determination as in the flowchart of FIG. c can flow in the order of the processing devices A1 → B1 → C1. At this time, since the flow of the processing devices A1 → B1 → C1 is determined in consideration of the load distribution once, it is considered that the load will be distributed in the same manner when the next operation is performed.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications can be made based on the technical concept of the present invention.

The present invention is not limited to a semiconductor device production line, but is a job shop type production in which one of a group of functional devices of the same type is selected and worked, and a work is sent to a group of devices in the next process. The present invention can be applied as a production control method for all products produced by the method.

Further, based on not only the processing history in the immediately preceding processing step but also the processing history up to several steps before or all the past processing histories of the work, the processing in the step to be performed now is performed. The processing device may be selected. For example, in the above embodiment, in the process c, only the correspondence between the work 1 and the processing device B1 in the process b is viewed, but the correspondence may be viewed in consideration of the processing device A1.

[0031]

According to the first aspect of the present invention, it is not necessary to prepare a plurality of production lines on which workpieces flow in consideration of the correspondence between the respective devices and the expected load, thereby reducing labor.

According to the second aspect of the present invention, the operator is given the selectivity of the apparatus within a good range of the correspondence (compatibility), so that the optimum apparatus is selected in accordance with the operation state of the apparatus. Thus, the production capacity of the production line can be maximized.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a flow of a production control method according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a flow of the production control method.

FIG. 3 is a table showing a correspondence relationship between a device group A and a device group B as to whether processing is possible or not.

FIG. 4 is a table showing a correspondence relationship between a device group B and a device group C as to whether processing is possible or not.

FIG. 5 is a block diagram showing a flow of a conventional production control method.

[Explanation of symbols]

A: device group, A1: processing device, A2: processing device,
A3: Processing device, B: Device group, B1: Processing device,
B2 processing apparatus, B3 processing apparatus, C apparatus group,
C1 processing apparatus, C2 processing apparatus, C3 processing apparatus.

Claims (3)

[Claims] 1. A production control method for selecting one of a plurality of processing apparatuses having the same function and performing processing in one processing step of a workpiece. When the work reaches the processing step in which the processing apparatuses that can be processed are limited according to the correspondence relationship with the processing apparatuses of the other apparatus group in the process, a processing history indicating which processing apparatus has processed the work in the previous process And a processing device to be used in this processing step is specified based on the correspondence created in advance, and the processing of the work is performed by the specified processing device. When the processing of the work is completed, the work is A production control method, characterized in that processing performed by the processing device is recorded as a processing history. 2. The method according to claim 1, wherein, when specifying the processing device, if there are two or more options of the processing device, a processing device with less load is specified.
Production control method. 3. The production control method according to claim 1, wherein the work is a semiconductor wafer, and the processing is a processing for performing lens reduction projection exposure on the semiconductor wafer.