JP2008077370A - Production management system and production management method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production management system and a production management method capable of achieving a desired value of production volume while complying with a limit on production time. <P>SOLUTION: Precondition input information 1 about the specifications and the operating conditions of a production line is input via a precondition input means 2 and stored in a database 3 as preconditions 3a. A production line evaluation means 4 calculates a Q-Time upper limit based on the preconditions 3 and evaluates the production line by means of the ratio of the Q-Time upper limit to average processing time Ep per lot (i.e., upper limit WL for the number of work-in-process lots). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a production management system and a production management method for managing a production line in which production time is restricted by a predetermined restriction value, and in particular, for achieving a production value target value while complying with the production time restriction value. Regarding technology.

  In a conventional production management system, an upper limit (quality assurance time or quality retention time) is set for the time (Q-Time) from the process completion time of any process to the process start time of any process after that process. In the case where the product is in the production line, the waiting time does not exceed the quality assurance time by limiting the number of products (workpieces) waiting to be processed (the number of devices in progress) for a predetermined period (for example, Patent Document 1).

  In a series of process processing sections, a section in which an upper limit value (Tq) is set for the time from the process completion time (Te) of the first process to the process start time (Ts) of the last process is defined as a quality retention section (Q -Time interval). The upper limit value Tq is generally called quality assurance time (Q-Time).

  Judging whether to start processing in the first process in the Q-Time section of the product is defined as the input control in the Q-Time section. If it is determined that the process of the first process is not started by this input control, the product is temporarily put into a waiting state before the process of the first process is started.

  In addition, controlling the start of process processing so as to satisfy the Q-Time of the product in the process in the Q-Time section is defined as progress control in the Q-Time section. The progress control includes a process processing device reservation process, a process processing device occupation process before a product arrives, and a product process processing order change (overtaking, overtaking) processing.

  Q-Time is set to maintain quality, and Q-Time violation is defined as the fact that Q-Time cannot be satisfied, that is, the product waiting time is equal to or greater than Q-Time. Products that violate the Q-Time will take the following actions after the Q-Time period is complete. For example, in order to restore the quality, an unusual process is performed, or a redo process called a reproduction process is added, and the process in the Q-Time section is executed again.

  In addition to the above Q-Time, the product production time constraint value is the time from when the product is put into the production line until the product is completed (production period), or from the completion of processing of any process to the process. There is a time (inter-process work period) until the completion of the processing of any subsequent process.

  In addition, the input control and the progress control in the conventional production line may be performed automatically, manually, or may not be performed at all (assuming that the production capacity of the manufacturing apparatus is sufficient). is there. The input control and the progress control may be violated by Q-Time due to an error in human judgment when performed manually, or due to an error in assumptions relating to production capacity when not performed at all. Therefore, in order to prevent the Q-Time violation, it is necessary to automatically perform input control and progress control.

JP 2003-108213 A

  As described above, in the conventional production management system, it is necessary to perform the input control and progress control automatically. In this case, although the product production time constraint value can be observed, the Q-Time Since the work in progress before the section increases, there is a possibility that the target value of the production amount of the product cannot be achieved.

  In other words, in the conventional production management system, the production line capacity necessary for complying with the product production time constraints is not ensured when planning and designing the production line. Depending on the combination of the product production time constraint value and the product production volume target value, it may be impossible to operate a production line that balances these two values. . Therefore, it is necessary to operate the production line after quantitatively evaluating and grasping the degree of feasibility before starting the production line operation.

  The capacity of the production line is the first factor: the production volume per unit time of the entire production line (volume determined by the production line operating conditions), and the second factor is the production time within which production of products is restricted. (Production line operating conditions include processing capacity of manufacturing equipment (equipment), product process sequence, process processing time, allocation of assigned processes for manufacturing equipment, etc.) There is).

  Moreover, in the conventional production management system, although it is theoretically impossible to observe the constraint value of the production time of the product, the production time cannot be observed in an actual production line in many cases. This is because there is a problem that production operation conditions for complying with the constraint value of the production time of the product are not set appropriately.

  In addition, when the product production time constraint value is set in the quality hold time (Q-Time) in the partial quality hold interval (Q-Time interval) of the process sequence, the production line to comply with the quality hold time There was a problem that no production control system was established.

  That is, in the conventional production management system, there is a problem that it is difficult to achieve the target value of the production amount while observing the production time limit value.

  The present invention has been made in order to solve the above-described problems, and provides a production management system and a production management method capable of achieving a production value target value while complying with production time constraint values. It is intended to provide.

  The production management system according to the present invention is a production management system for managing a production line whose production time is restricted by a predetermined restriction value, and is a precondition for inputting a production line precondition relating to specifications and operation conditions of the production line. An input unit and a production line evaluation unit that obtains the predetermined constraint value based on the input precondition and evaluates the production line using a ratio between the predetermined constraint value and a processing time per production unit. With.

  The production management system according to the present invention evaluates a production line using a ratio between a predetermined constraint value that restricts production time and a processing time per production unit. Therefore, the target value of the production amount can be achieved while observing the production time constraint value.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a manufacturing apparatus (production apparatus) for manufacturing a desired product such as a semiconductor device is also simply referred to as an apparatus, and a manufacturing apparatus group including one or more manufacturing apparatuses is also simply referred to as an apparatus group. .

<Embodiment 1>
FIG. 1 is a configuration diagram showing a production management system according to Embodiment 1 of the present invention. The production management system shown in FIG. 1 includes a computer including a control unit such as a CPU, a storage unit such as a memory, an input unit such as a keyboard, and the like, and operates according to a predetermined program.

  In FIG. 1, precondition input information 1 is input information of production line preconditions (hereinafter simply referred to as preconditions) relating to specifications, operation conditions, etc. of a production line including a plurality of manufacturing apparatuses (the preconditions of this precondition). Specific examples will be described later in detail).

  The prerequisite input means 2 is means for inputting the prerequisite input information 1 to the database 3.

  The database 3 includes a precondition 3a, a production line evaluation result 3b, a manufacturing device classification result 3c, an improvement plan 3d, a product work-in-progress state 3e as a product work-in-progress state in the production line, a work-in-progress management flag 3f, and a product The progress control command value 3g.

  The production line evaluation means 4 is a means for evaluating the production line based on the precondition 3a.

  The manufacturing apparatus classification means 5 is a means for classifying manufacturing apparatuses based on the production line evaluation result 3b output from the production line evaluation means 4, and the classified result is stored as a manufacturing apparatus classification result 3c in the database 3. (Memorized).

  The improvement plan calculation means 6 is a means for calculating a plan for improving the evaluation value of the manufacturing apparatus based on the manufacturing apparatus classification result 3c, and the calculated plan is stored as an improvement plan 3d in the database 3. .

  The precondition changing means 8 is means for changing the precondition 3a based on the improvement plan 3d (in other words, executing the improvement plan 3d).

  The production management system main body 9 is a system main body that manages a production line using a known existing technique.

  The in-process status recognition means 10 is means for recognizing information on which device is waiting for processing in which process the product on the production line is processed from, or which device is being processed from the production management system 9. It is. Information recognized by the in-process status recognition means 10 is stored in the database 3 as a product in-process status 3e.

  The progress control means 11 is a means for controlling the progress of the product on the production line from the production line evaluation result 3b and the product work status 3e.

  The information output means 12 is means for outputting information stored in the database 3 to an external output device such as an external display or printer.

  In FIG. 1, the precondition input unit 2 is provided by an input unit such as a keyboard. The production line evaluation unit 4, the manufacturing apparatus classification unit 5, the improvement plan calculation unit 6, the precondition changing unit 8, the in-process state recognition unit 10, and the progress control unit 11 are respectively controlled by a control unit such as a CPU as a predetermined program. It is provided by operating according to The database 3 is stored in storage means such as a memory.

  FIG. 2 is a flowchart schematically showing the flow of production of products in the entire factory. In FIG. 2, step S1 which is the first step, steps S2 to S3 which are intermediate steps, and step S4 which is the last step are shown. In FIG. 2, the case where the intermediate process is two steps including steps S <b> 2 to S <b> 3 is shown, but the process is not limited to two steps. Moreover, in FIG. 2, although one series of processes which consist of step S1-S4 is shown, such a series of processes may exist with two or more for every product. For example, when the product is a semiconductor device, a marking process on the wafer is executed in step S1, and a final inspection process is executed in step S4.

  In FIG. 2, the time from the process start time of step S1 to the process completion time of step S4 is referred to as a production period 17. In any two processes (for example, steps S2 and S3), the time from the process completion time of the previous process (step S2) to the process completion time of the subsequent process (step S3) is referred to as an inter-process work period 18. .

  FIG. 3 is a flowchart schematically showing the setting of the upper limit value to the time (Q-Time) from the process completion time of an arbitrary process to the process start time of an arbitrary process after that process.

  In FIG. 3, steps S12 to S14 that are steps included in a section in which Q-Time is restricted by the upper limit (Q-Time section 24), step S11 that is a process immediately before the Q-Time section 24, Step S15 which is a process immediately after the Q-Time section 24 is shown. In the present specification, the term “interval” is used for both the meaning of a temporal region and the meaning of a spatial region.

  Q-Time in FIG. 3 is the time from the processing completion time (Te) in step S12 to the processing start time (Ts) in step S14, as shown in equation (1), and is an upper limit value (Q-Time upper limit). Value).

  FIG. 4 is a schematic diagram showing a Q-Time section 24 composed of two devices 28 and 29. The device 28 is a manufacturing device in charge of the process in step S12, which is the first step in the Q-Time section 24 of FIG. 3, and the device 29 is the last step in the Q-Time section 24 of FIG. It is a manufacturing apparatus in charge of processing in step S14. In FIG. 4, only two devices 28 and 29 are schematically shown, but in actuality, the previous process of the device 28, the subsequent process of the device 29, or the steps S 12 and S 14 are performed. Other devices (device groups) in charge of the respective processes are arranged in the intermediate steps.

  In FIG. 4A, four lots 31, 32a, 32b, and 33 are indicated by solid lines. A lot is a carrier capable of storing a plurality of wafers together, and is a unit of process processing. Lot 31 is a lot immediately after completion of processing in apparatus 28, lot 32 a is a lot that is being transferred from apparatus 28 to apparatus 29, lot 32 b is a lot waiting for processing in apparatus 29, and lot 33 is in apparatus 29. The lot being processed.

  In FIG. 4B, when the time point when the lot 31 has been processed by the apparatus 28 is defined as a reference time point, the production time (from the reference time point until the lot 31 has completed the process by the apparatus 29 ( The inter-process construction period) is the number of in-process lots W (the lots 32a, 32b, and 33 in FIG. WT (the processing time of the lots 32a, 32b, 33) + T (the processing time of the lots 32a, 32b, 33) using the (average) processing time T required for the processing of each lot in the apparatus 29. Lot 31 processing time) = (W + 1) T.

  Generally, in a production management system, (average value of product production period) / (shortest production period of product) is called a Kp magnification (that is, the Kp magnification is the total time required for performing a predetermined process). And the net time necessary for performing only the main body of the predetermined process, and hereinafter abbreviated as KX). In FIG. 4A, the product production period is (W + 1) T corresponding to the inter-process period, and (the shortest product production period) is T corresponding to the processing time of the lot 31, so FIG. ), KX = (W + 1) = 4. That is, in order to process the lot 31, not only the processing time T (net time) of the lot 31 itself but also the time 3T (WT) for waiting for the processing of the lots 32a, 32b, 33 is required. 4 (KX = W + 1) times of the processing time T (total time) is required.

  FIG. 5 is a flowchart showing an overall processing flow (production management method) in the production management system according to the present embodiment.

  First, when the process is started, the precondition input unit 2 in the production line executes a process of inputting the precondition input information 1 in step S21. The input precondition input information 1 is stored in the database 3 as a precondition 3a.

  Next, in step S22, the production line evaluation unit 4 executes processing for evaluating the production line from the precondition 3a stored in the database 3 in step S21. The evaluated result is stored in the database 3 as a production line evaluation result 3b.

  Next, in step S23, the manufacturing apparatus classification unit 5 executes a process of classifying the manufacturing apparatus based on the production line evaluation result 3b stored in the database 3 in step S22. The classified result is stored in the database 3 as a manufacturing apparatus classification result 3c.

  Next, in step S24, the improvement plan calculation means 6 executes a process of selecting a device (improvement device) to be improved.

  Next, in step S25, the improvement plan calculation means 6 executes a process for calculating a plan for improving the device selected in step S24. The calculated plan is stored in the database 3 as an improvement plan 3d.

  Next, in step S26, the precondition changing unit 8 executes a changing process on the precondition 3a stored in the database 3 in step S21 using the improvement plan 3d stored in step S25 (in other words, Execute improvement plan 3d, or make improvements). The changed precondition 3 a is overwritten and saved in the database 3.

  Next, in step S27, a process for determining whether or not all the devices to be improved have been improved is executed. When it is determined that there is a device that has not been improved, the process returns to step S24, and when it is determined that all the devices to be improved have been improved, the process proceeds to step S28.

  Next, in step S <b> 28, a process for determining whether to execute production line progress control is executed. When it is determined that the production line progress control is to be executed, the process proceeds to step S29, and when it is determined that the production line progress control is not to be executed, the series of processing ends.

  Next, in step S29, the work-in-progress recognition unit 10 uses the production management system body 9 to execute processing for recognizing the product work-in state in the production line. The recognized information is stored in the database 3 as a product work-in-progress state 3e.

  Next, in step S30, a process of selecting a product that is subject to progress control is executed. The selected result is stored in the database 3 as an in-process management flag 3f and a progress control command value 3g.

  Next, in step S31, the progress control means 11 executes a process of transmitting the progress control command value 3g stored in the database 3 in step S30 to the production management system main body 9.

  Next, in step S32, the production management system main body 9 performs progress control on the product selected in step S30 based on the progress control command value 3g transmitted by the progress control means 11 in step S31. Then, the process returns to step S28.

  Thus, a series of processing is completed.

  FIG. 6 is a flowchart showing detailed steps of the production line evaluation process shown in step S22 of FIG.

  First, in step S41, the production line evaluation unit 4 executes a process of inputting the precondition 3a stored in the database 3 in step S21. Information included in the precondition 3a includes a manufacturing apparatus group, the number of manufacturing apparatuses included in the manufacturing apparatus group, a process sequence in which a processing order of a series of processes for each product necessary to complete a product is determined, Correspondence between each process step in the process sequence and a manufacturing apparatus group capable of performing the process, a lot size (the number of wafers that can be stored in one lot) as a processing unit of each process step in the process sequence, and the process The processing time required for processing of each processing step in the series or the relationship between the processing time and the lot size, and the upper and lower limits of the number of batch processes (number of lots that can be processed simultaneously) for each processing step in the process series , The upper and lower limits of the production period, the upper and lower limits of the inter-process period, and the limit value of the waiting time from the process end time of the first process to the start of the last process in any process series Time interval (Q-Time interval), upper limit of waiting time limit (Q-Time) of the process interval, production volume per unit time for each product type (production line input amount), manufacturing equipment group or manufacturing equipment (For example, the time required to process one lot, the number of lots that can be processed per unit time, etc.), the operating rate of the manufacturing apparatus group, and the like.

  Next, in step S42, processing for calculating an average processing time Ep (i) necessary for processing one lot in a predetermined device group i (i: natural number) to be evaluated is executed. The average processing time Ep (i) is, for example, as shown in the following formula (2), a process p and a process j in which the device group i is in charge of processing, a device group k capable of processing the process p, and a process j is a process processing time Tc (j) that is a time required for processing in j, a process number Pc (i) that is the total number of processes that the device group i is in charge of, and a total number of devices that are included in the device group i. It can be obtained from the number of devices Ts (i) and the number of batches Bs (i) of the device group i. Note that the batch number Bs (i) represents the number of lots that can be simultaneously processed in the apparatus group i as described above, and is normally set to 1.

  In the equation (2), modeling is performed using a process processing time Tc (j) that is a time required for the process in the process j in which the device group i is in charge of the process. Actually, each device included in the device group i may have different processing times due to differences in processing capability and setup time due to differences in internal configuration, but the process processing time Tc (j) When used, modeling is performed uniformly as the device group i.

  Therefore, in order to perform modeling using the process processing time Tc (j) as shown in the equation (2), the processing time in a plurality of apparatuses used in the desired process j is almost the same. There is a need.

  Similarly, the product lot size and product type combination may differ from product to product, but the process processing time Tc (j) is used as shown in equation (2) (uniform). In order to perform modeling, as a premise, the combination of product lot size and product type needs to be substantially the same in each manufacturing apparatus, as is the processing time.

  When this condition is satisfied, as shown in the first term of the equation (2), the sum of the process processing times Tc (j) (ΣTc ( j)), the number of processes Pc (i) that is the total number of processes that the device group i is in charge of and the number of devices Ts (i) that is the total number of devices included in the device group i and the simultaneous processing in the device group i By dividing by the batch number Bs (i), which is the number of possible lots, the average processing time of the (assumed) apparatus group i when the process p is assumed to be handled only by the apparatus group i is obtained. As shown in the second term, the first term is multiplied by the sharing rate (Ts (i) / Σ (Ts (k))) relating to the charge of the device group i, thereby correcting (assuming the assumption). It is possible to calculate the average processing time Ep (i) per lot of the device group i.

  In Equation (2), when the product lot size and the combination of product types are limited in detail, is the processing time calculated by performing some modeling expressed in a format different from Equation (2)? Alternatively, it is necessary to obtain the processing time by actual measurement.

  In the above description, the case of calculating the average processing time (Ep (i)) has been described. However, the average processing time is not limited to the average processing time, or the average insertion interval (the processing interval time proportional to the processing capability of the device group i ( Tact time)) may be calculated. Further, the average processing time and the average charging interval may not be obtained by calculation using the formula (2), or may be obtained by actual measurement.

  Next, in step S43, processing for calculating an in-process lot upper limit value WL (i) representing the upper limit of the in-process lot number W is executed. Hereinafter, the in-process lot number upper limit WL (i) will be described in detail.

  In FIG. 4, basically, if the number of in-process lots W between processes is 0, the apparatus 29 does not cause a processing wait time, so that the Q-Time can always be observed. Even when the number of in-process lots W is 1 or more, the Q-Time can be protected by limiting the number of in-process lots W according to a predetermined rule.

  In the present embodiment, the in-process lot upper limit WL (i) is set for each device group i (using Q-Time (i) defined uniquely for the device group i) as shown in the following equation (3). In addition, it is determined using the following formula (4) whether the number of in-process lots W based on the precondition 3a does not exceed the in-process lot number upper limit WL (i). The device group i is in charge of the process of step S14, which is the last step in the Q-Time section 24 of FIG. 3, and corresponds to the device 29 of FIG.

  Below, the basis of Formula (3) is demonstrated. As described above, in equation (3), instead of the average processing time (unit: time / lot), the average lot input interval (unit: time / lot) to the apparatus 29 may be used.

  For example, in FIG. 4, the processing waiting time (Ts−Te) in the apparatus 29 viewed from the lot 31 is expressed by the following formula (5) using the (average) processing time T in the apparatus 29.

  As described above, in FIG. 4, the in-process lot number W in the equation (5) is the number of the lots 32a, 32b, 33, that is, three.

  Here, the in-process lot number W when the upper limit value of (Ts−Te) in Equation (5) is Q-Time (i) is defined as the in-process lot number upper limit value WL (i). Q-Time (i) is a Q-Time defined as unique to the device group i as described above, and specifically, one is selected from a plurality of Q-Times unique to the device group i. Is. In this selection, for example, a minimum value may be selected from a plurality of Q-Times, or an average value, a maximum value, a mode value, or the like may be selected.

  In Expression (5), when the average processing time Ep (i) of Expression (3) is substituted as the average processing time T, (Ts−Te) = W × Ep (i) = W × Q-Time (i) / WL (i) = Q-Time (i) × W / WL (i), but when W satisfies Equation (4), W / WL (i) ≦ 1, so (Ts−Te ) ≦ Q-Time (i). That is, if W satisfies Expression (4), Q-Time (i) can be maintained.

  The following formula (6) is obtained by substituting the formula (2) into the formula (3). By using Expression (6), it is possible to specifically calculate the in-process lot number upper limit WL (i) based on the precondition 3a.

  Next, in step S44, the number of processing waiting lots Wρ in the device group i is calculated based on the operating rate ρ unique to the device group i using Equation (7).

  Next, in step S45, the in-process lot number upper limit WL (i) is compared with the number of processing waiting lots Wρ. As a result of comparison, if WL (i) ≧ Wρ, the process proceeds to step S47. If WL (i) ≧ Wρ is not satisfied, the process proceeds to step S46, and the risk is determined to be the highest (Highest-risk) and evaluated. The process ends.

  Next, in step S47, KX is calculated. As described above, KX can be obtained by calculating (average value of actual product production period) / (shortest product production period) using precondition 3a.

  Next, in step S48, the in-process lot number upper limit WL (i) is compared with the in-process lot number W1 based on the precondition 3a. The number of in-process lots W1 varies depending on the production line and can be arbitrarily set. For example, by setting W1 = KX−1, an appropriate determination can be made (in FIG. 4, ahead of the lot 31). The number of lots 32a, 32b, 33 that need to be processed by the apparatus 29, that is, 3 corresponds to the number of in-process lots W1). As a result of the comparison, if WL (i) ≧ W1, the process proceeds to step S50. If WL (i) ≧ W1, the process proceeds to step S49, where the risk is determined to be high (High-risk), and the evaluation process is performed. finish.

  Next, in step S50, the in-process lot number upper limit WL (i) is compared with the in-process lot number W2 based on the precondition 3a. The in-process lot number W2 varies depending on the production line and can be arbitrarily set within a range satisfying W2> W1, but for example, by setting W2 = KX + 1, an appropriate determination can be made. As a result of the comparison, if WL (i) ≧ W2, the process proceeds to step S52. If WL (i) ≧ W2, the process proceeds to step S51, and it is determined that the risk is medium (Middle-risk). End the evaluation process.

  Next, in step S52, the in-process lot number condition value WL (i) is compared with the in-process lot number W2 × the number of processes Pc (i). As a result of the comparison, if WL (i) ≧ W2 × Pc (i), the process proceeds to step S54 to determine that the risk is minimum (Lowest-risk), and WL (i) ≧ W2 × Pc (i). If not, the process proceeds to step S53, it is determined that the risk is low (Low-risk), and the evaluation process is terminated.

  Next, in step S55, processing for determining whether or not the evaluation of all the device groups i has been completed is executed. If it is determined that the device group i that has not been evaluated remains, the process returns to step S42. If it is determined that all the device groups i have been evaluated, the process proceeds to step S56.

  Next, in step S56, after the production line evaluation result is stored in the database 3, the process is terminated.

  Thus, a series of processing is completed.

  Next, the production line evaluation process of FIG. 6 will be described using specific numerical examples.

  For example, in the device group A, the Q-Time upper limit value is 480, the average processing time Ep (A) is 37.1, the operation rate ρ is 0.990, the number of processes Pc (A) is 3, and the KX is If it is 3, the in-process lot number upper limit WL (A) = 480 / 37.1 = 12.938, and the number of processing waiting lots Wρ = 0.990 / (1−0.990) = 99. Therefore, since the result of determination in step S45 is no, it is evaluated as Highest-risk in step S46.

  Further, for example, in the device group B, the Q-Time upper limit value is 30, the average processing time Ep (B) is 17.0, the operation rate ρ is 0.290, and the number of processes Pc (A) is 1. If KX is 3, the in-process lot number upper limit WL (B) = 30 / 17.0 = 1.765, and the number of processing waiting lots Wρ = 0.290 / (1−0.290) = 0.408 Thus, the number of in-process lots W1 = KX-1 = 2. Therefore, since the result of determination in step S48 is no, it is evaluated as High-risk in step S49.

  Further, for example, in the device group C, the Q-Time upper limit value is 120, the average processing time Ep (C) is 43.6, the operation rate ρ is 0.330, and the number of steps Pc (C) is 1. If KX is 3, the in-process lot number upper limit WL (C) = 120 / 43.6 = 2.752, and the number of processing waiting lots Wρ = 0.330 / (1−0.330) = 0.493 Thus, the number of in-process lots W1 = KX-1 = 2 and the number of in-process lots W2 = KX + 1 = 4. Accordingly, since the result of determination in step S50 is no, it is evaluated as Middle-risk in step S51.

  For example, in the device group D, the Q-Time upper limit value is 480, the average processing time Ep (D) is 50.2, the operation rate ρ is 0.900, and the number of processes Pc (D) is 4. If KX is 3, the in-process lot number upper limit value WL (D) = 480 / 50.2 = 9.562, the number of processing waiting lots Wρ = 0.900 / (1-0.900) = 9, The number of work lots W1 = KX-1 = 2 and the number of work lots W2 = KX + 1 = 4. Accordingly, since the result of determination in step S52 is no, it is evaluated as Low-risk in step S53.

  Further, for example, in the device group E, the Q-Time upper limit value is 360, the average processing time Ep (E) is 3.2, the operation rate ρ is 0.990, and the number of processes Pc (E) is 18. If KX is 3, the in-process lot number upper limit WL (E) = 360 / 3.2 = 112.5, the number of waiting lots Wρ = 0.990 / (1−0.990) = 99, The number of work lots W1 = KX-1 = 2 and the number of work lots W2 = KX + 1 = 4. Therefore, since the result of determination in step S52 is yes, it is evaluated as Low-risk in step S54.

  FIG. 7 shows the case where the number of processes Pc (i) = 3, the number of in-process lots W1 = KX−1, and the number of in-process lots W2 = KX + 1, depending on the values of KX and the number of in-process lot numbers WL (i). It is the graph which showed the classification according to the risk on the KX-WL plane. As shown in FIG. 7, when KX is constant, the risk becomes smaller as the in-process lot number upper limit value WL (i) increases, and when the in-process lot number upper limit value WL (i) is constant, KX. The larger the is, the smaller the risk. In FIG. 7, it is assumed that the Q-Time upper limit value and the average processing time Ep (i) are constant.

  As described above, in the production management system and the production management method according to the present embodiment, the input assumption is used to manage the production line in which the production time is restricted by the predetermined restriction value (Q-Time upper limit value). The upper limit value of Q-Time is obtained based on condition 3a, and the ratio between the upper limit value of Q-Time and the average processing time Ep (average processing time per production unit) per lot (as shown in Equation (3)) In other words, the production line is evaluated using the in-process lot number upper limit WL (i)). Therefore, the target value of the production amount can be achieved while observing the production time constraint value.

Further, the precondition 3a includes information on the processing capacity of each manufacturing apparatus constituting the production line,
It includes at least information on a waiting time (Q-Time) when a lot is transported between each manufacturing apparatus. Therefore, the production line can be quantitatively evaluated and controlled.

  In addition, the production line can be further quantitatively evaluated and controlled by performing the evaluation using the KX and the operation rate.

  In addition, by classifying according to the evaluation, it is possible to make improvements, etc. in order from the equipment that is most likely not to comply with the production time constraint value. The target value can be achieved.

<Embodiment 2>
FIG. 8 is a flowchart showing detailed steps of the improvement plan calculation process shown in steps S24 to S27 of FIG.

  First, in step S61, the improvement plan calculation means 6 executes a process of inputting the precondition 3a, the production line evaluation result 3b, and the manufacturing apparatus classification result 3c stored in the database 3 in steps S21 to S23, respectively.

  Next, in step S62, based on the manufacturing apparatus classification result 3c input in step S61, a process for determining whether there is an apparatus group to be improved is executed. If it is determined that there is a device group to be improved, the process proceeds to step S63, and if it is determined that there is no device group to be improved, the process ends.

  Next, in step S63, a predetermined device group is selected (referred to as device group i), and processing for determining whether or not improvement is required for this device group i is executed. If it is determined that improvement is necessary, the process proceeds to step S64, and if it is determined that improvement is not necessary, the process proceeds to step S68 to set (record) that no improvement is to be performed on the device group i. Later, the process returns to step S62.

  Next, in step S64, using the equation (6) according to the first embodiment, a process of calculating an in-process lot number upper limit WL (i) for the device group i is executed.

  Next, in step S65, a process of setting the number of in-process lots W0 that is a determination criterion (target value) for improvement is executed. Specifically, the number of in-process lots W0 may comply with KX, the number of processes Pc (i), the operating rate ρ of the device group i, and the upper limit of Q-Time (High-risk, Middle-risk, Low-risk) can be automatically calculated by setting the user to a desired value.

  Next, in step S66, for the device group i, the process processing time Tc (i), the number of steps Pc (i), the number of devices Ts (i), and Σ (Ts (k)) satisfying WL (i) = W0. A plurality of combinations are obtained as improvement plan candidates. At this time, as shown in the following formula (8), when the process processing time Ts (i) can be expressed as a process processing time Ts (i, n) as a function of the number of wafers n, the wafer The number n may be used. In equation (8), value a corresponds to the time required for processing per wafer, and value b corresponds to the time required regardless of the number of wafers.

  Next, in step S67, a process for determining whether or not each of the plurality of improvement plan candidates obtained in step S66 is realizable is executed. If there are one or more feasible improvement plan candidates, the process proceeds to step S69. If there is no feasible improvement plan candidate, the process proceeds to step S68 to set (record) that no improvement is to be performed on the device group i. ) And then the process returns to step S62.

  Next, in step S69, a process of selecting one from one or more improvement plan candidates determined to be realizable in step S67 is executed. The calculated plan is stored in the database 3 as an improvement plan 3d.

  Next, in step S70, the precondition changing unit 8 executes a changing process on the precondition 3a input in step S61, using the improvement plan 3d stored in step S69. The changed precondition 3 a is overwritten and saved in the database 3. Thereby, the improvement plan 3d is executed.

  Next, in step S71, after setting (recording) that the device group i has been improved, the production line evaluation process in step S37 and the manufacturing apparatus classification process in step S38 are sequentially executed, and the process returns to step S73. .

  Thus, a series of processing is completed.

  Next, the improvement plan calculation process of FIG. 8 will be described using specific numerical examples.

  For example, in the device group C, the Q-Time upper limit value is 120, the average processing time Ep (C) is 43.6, the operation rate ρ is 0.330, the number of processes Pc (C) is 1, and the KX is 3 and the number of devices Ts (C) is 1 and Σ (Ts (k)) is 1, the in-process lot number upper limit WL (C) = 120 / 43.6 = 2.752, and waiting for processing The lot number Wρ = 0.290 / (1−0.290) = 0.493, the in-process lot number W1 = KX−1 = 2, and the in-process lot number W2 = KX + 1 = 4.

  Under these conditions, a case will be described in which an improvement is made such that the number of in-process lots W0 = 4 (that is, WL (i) = 4), which is the target value of the number of in-process lots W (W2 × Pc (C)> Since W0 = WL (C) ≧ W2, it becomes Low-risk). In Expression (3), when WL (C) = 4 and Q-Time (C) = 120, Ep (C) = 30. Accordingly, the process processing time Tc (i), the number of processes Pc (C), or the number of devices Ts (C) is changed so that the average processing time Ep (C) decreases from 43.6 to 30, or the equation What is necessary is just to improve so that the apparatus group i which can process the process p is increased so that it may become (SIGMA) (Ts (k)) = 2 in (2). Note that Σ (Ts (k)) = 2 is obtained by the following calculation. If the total number of W0 devices is Σ (Ts ′ (k)), then WL / W0 = Σ (Ts (k)) / Σ (Ts ′ (k)). Therefore, Σ (Ts ′ (k)) = Σ (Ts (k)) × W0 / WL = 1 × 4 / 2.752 = 1.453 ≦ 2.

  As described above, in the production management system and the production management method according to the present embodiment, the improvement (change of the preconditions) is performed according to the evaluation, thereby improving the factory before the operation. Therefore, the target value of the production amount can be achieved while observing the production time constraint value.

<Embodiment 3>
FIG. 9 is a flowchart showing detailed steps of the progress control process shown in steps S28 to S32 of FIG. FIG. 10 is a schematic diagram illustrating an example of a Q-Time section in which the progress control process of FIG. 9 is performed. As described above, in the progress control, the process start in the process in the Q-Time section 24 is controlled so as to satisfy the Q-Time of the product, and in the input control, the process start in the Q-Time section 24 of the product is controlled. In the first process (step S12 in FIG. 3), it is determined whether or not to start the process.

  In FIG. 10, the device A1 included in the device group A is in charge of the process in step S12, which is the first step in the Q-Time section 24, and corresponds to the device 28 in FIG. In addition, the devices B1 and B2 included in the device group B and the device C1 included in the device group C are in charge of the process in step S14 which is the last step in the Q-Time section 24. It corresponds to 29. The device group A and device group B constitute a Q-Time interval 24b, and the device group A and device group C constitute a Q-Time interval 24c.

  The third embodiment is characterized in that the device A1 performs progress control by selecting a device with a relatively small processing reservation counter from the devices B1, B2, and C in charge of the processing in step S14. To do. In addition, it is preferable that the apparatus A1 controls the input of all lots in the order of first-in first-out (first-in first-out may be performed only for the lots that can be first-in first-out).

  As shown in FIG. 9, first, in step S81 (corresponding to step S29 in FIG. 5), as in the first embodiment, the work-in-progress recognition unit 10 uses the production management system 9 to produce products on the production line. The process of recognizing the in-process status is executed. The recognized information is stored in the database 3 as a product work-in-progress state 3e. This information includes the number of in-process lots of the device group i in the Q-Time section 24 and the number of in-process lots of the device E (i, j) included in the device group i.

  Next, in step S82, the number of in-process lots of the device group i obtained in step S81 is set as a processing reservation counter G (i), and the number of in-process lots of the device E (i, j) obtained in step S81 is reserved for processing. As the counter S (i, j), a value obtained by adding the batch number Bs (i) to the in-process lot number upper limit value WL (i) obtained in step S43 (evaluation process in FIG. 6) is set as a new in-process lot number upper limit value. Each is set (stored) as WL (i). Thereby, processing for initializing the processing reservation counters G (i), S (i, j) and the in-process lot number upper limit value WL (i) is executed. As described above in the first embodiment, the batch number Bs (i) is the number of lots that can be processed simultaneously in the apparatus group i, and is normally set to 1.

  Next, in step S83, processing for selecting a product to be subject to progress control is executed. The selected result is stored in the database 3 as an in-process management flag 3f and a progress control command value 3g. Specifically, in FIG. 3, the product waiting for the process of Step S12 which is the first process in the Q-Time section 24 after the process of Step S11 which is the process immediately before the Q-Time section 24 is completed. Selected as the target of progress control.

  Next, in step S84, the device group i (the device 29 in FIG. 4 or the device groups B and C in FIG. 10) that can process step S14, which is the last step in the Q-Time section 24, is processed from all the device groups. Equivalent) and satisfying WL (i) ≧ G (i), and processing for extracting all of them as transport destination candidates is executed.

  Next, in step S85, the apparatus group i having the maximum (WL (i) -G (i)) is selected as the transport destination from all the candidates extracted in step S84 (in this embodiment). For example, it is assumed that the device group B (including the devices B1 and B2) of Fig. 10 is selected, and the transport reservation counter or the processing reservation counter G (i) is the smallest. Device group i may be selected). Then, a value obtained by adding the batch number Bs (i) to the processing reservation counter G (i) is set (stored) as a new processing reservation counter G (i).

  Next, in step S86, the process in step S12, which is the first step in the Q-Time section 24, is started (corresponding to the device 28 in FIG. 4 or the device group A in FIG. 10).

  Next, in step S87, the device E (i, j) having the smallest processing reservation counter S (i, j) is selected as the transport destination from the device group (device group B) selected in step S85. (In the present embodiment, for example, the device B1 in FIG. 10 is selected). A value obtained by adding the batch number Bs (i) to the processing reservation counter S (i, j) is set (stored) as a new processing reservation counter S (i, j).

  In steps S84 to S87 described above, the counting is performed by paying attention only to the lots transported from the device in charge of processing in step S12 (A1 etc.) to the device in charge of processing in step S14 (B1 etc.). However, since the devices A1 and B1 usually deliver lots to and from other devices other than these, the following steps S88 to S90 also count the lot delivery with devices other than the Q-Time section. I do.

  Next, in step S88, a device group i that processes a later process in a normal process processing section (in other words, a process processing section in which Q-Time is not set) configured by two device groups, is WL. (I) A process that searches for a condition that satisfies G (i) and extracts all of them as transfer destination candidates is executed.

  Next, in step S89, the device group i having the largest (WL (i) -G (i)) is selected as the transport destination from all the candidates extracted in step S88 (as the transport destination, Alternatively, the device group i having the smallest processing reservation counter G (i) may be selected). Then, a value obtained by adding the batch number Bs (i) to the processing reservation counter G (i) is set (stored) as a new processing reservation counter G (i).

  Next, in step S90, the device E (i, j) having the smallest processing reservation counter S (i, j) is selected from the device group i selected in step S89 as the transport destination. Then, the conveyance of the product (lot) to the apparatus E (i, j) is started, and a value obtained by adding the batch number Bs (i) to the processing reservation counter S (i, j) is set as a new processing reservation counter S. It is set (stored) as (i, j).

  Next, in step S91, a process is performed in which the apparatus E (i, j) that has completed the process is searched from the apparatus group i selected in step S85 and all are extracted as transfer destination candidates.

  Next, in step S92, for the device E (i, j) extracted in step S91, a value obtained by subtracting the batch number Bs (i) from the processing reservation counter G (i) is set as a new processing reservation counter G (i). And a value obtained by subtracting the batch number Bs (i) from the processing reservation counter S (i, j) is set (stored) as a new processing reservation counter S (i, j).

  Next, in step S93, a process for calculating an in-process lot number upper limit value WL (i) for the device group i is executed using the equation (6) according to Embodiment 1, and a new in-process lot number upper limit value WL is executed. Set (store) as (i). As a result, the in-process lot number upper limit WL (i) is updated.

  Next, in step S94, a process for determining whether or not to end the progress control process is executed. If it is determined that the progress control process should not be terminated, the process returns to step S83, and if it is determined that the progress control process should be terminated, the progress control process is terminated.

  Thus, a series of processing is completed.

  As described above, in the production management system and the production management method according to the present embodiment, the processing reservation counter G () is obtained by counting processing reservations in a plurality of manufacturing apparatuses constituting the production line in units of the number of in-process lots. i) and S (i, j). Therefore, as compared with the first embodiment, the production value target value can be achieved while observing the production time constraint value.

  In the above description, the last process in the Q-Time section 24 from one device group (A) in charge of the processing in step S12 which is the first process in the Q-Time section 24 is shown in FIG. Although the case where the lot is transported to the two device groups (B, C) in charge of the processing in step S14 has been described, the present invention is not limited to this, or as shown in FIG. Similarly, when the lot is transported from the two device groups (A ′, C ′) in charge of the processing in step S1 to the single device group (B ′) in charge of the processing in step S14, the progress is similarly made. Control can be performed. Further, the devices A1 ′ and C1 ′ shown in FIG. 11 may carry out first-in first-out of all lots, or may perform first-in first-out only for the lots that can be first-in first-out, as with the device A1 shown in FIG. .

<Embodiment 4>
In the third embodiment, the case where the progress control is performed using the number of in-process lots (based on a counter or the like) has been described. However, when the number of in-process lots is used, the calculation time is short, but when lots with different lot sizes are mixed, the processing time for each lot differs depending on the lot size. There are things that cannot be done. In order to prevent this, it is effective to perform progress control using the lot processing time instead of the number of in-process lots.

  FIG. 12 is a flowchart showing the detailed steps of the progress control process shown in steps S28 to S32 in FIG. 5, as in FIG.

  First, in step S101 (corresponding to step S29 in FIG. 5 and step S81 in FIG. 9), as in the first and third embodiments, the in-process status recognition means 10 uses the production management system 9 to produce products on the production line. The process of recognizing the in-process status is executed. The recognized information is stored in the database 3 as a product work-in-progress state 3e. This information includes the number of in-process lots of the device group i in the Q-Time section 24 and the number of in-process lots of the device E (i, j) included in the device group i.

  Next, in step S102, the product of the number of in-process lots of the device group i obtained in step S101 and the inter-process processing time Tc (j) in the device group i is obtained as a processing reservation counter Gt (i), and is obtained in step S101. The product of the number of in-process lots of the device E (i, j) and the inter-process processing time Tc (i, j) in the device E (i.j) is set as the processing reservation counter St (i, j) ( Remember). As a result, processing for initializing the processing reservation counters G (i) and S (i, j) is executed. In this embodiment, since the progress control is performed using the lot processing time instead of the number of in-process lots, the in-process lot number upper limit WL (i) is not used unlike in the third embodiment, and The inter-process processing time Tc is used instead of the batch number Bs (i).

  Next, in step S103, processing for selecting a product to be progress controlled is executed. The selected result is stored in the database 3 as an in-process management flag 3f and a progress control command value 3g. Specifically, in the same manner as in the third embodiment, in FIG. 3, the process of step S11, which is the process immediately before the Q-Time section 24, is completed, and the first process in the Q-Time section 24 is step S12. A product waiting for processing is selected as a target for progress control.

  Next, in step S104, the device group i (the device 29 in FIG. 4 or the device groups B and C in FIG. 10) that can process step S14, which is the last step in the Q-Time section 24, is processed from all the device groups. Equivalent) and satisfying Q-Time (i) ≧ Gt (i) + αt (i), and a process of extracting all as transport destination candidates is executed. Here, the parameter αt (i) is a time required until the device group i that is currently stopped due to a failure or the like can be processed, and changes every moment.

  Next, in step S105, the device group i having the maximum (Q-Time (i) -Gt (i) -αt (i)) is selected as the transport destination from all candidates extracted in step S104. (A group of devices (i) with the smallest processing reservation counter Gt (i) may be selected as the transport destination). Then, a value obtained by adding the inter-process processing time Tc (i) to the processing reservation counter Gt (i) is set (stored) as a new processing reservation counter Gt (i).

  Next, in step S106, the process of step S12, which is the first process in the Q-Time section 24, is started.

  Next, in step S107, the device E (i, j) having the smallest processing reservation counter St (i, j) is selected from the device group i selected in step S105 as the transport destination. Then, a value obtained by adding the inter-process processing time Tc (i) to the processing reservation counter St (i, j) is set (stored) as a new processing reservation counter St (i, j).

  In steps S104 to S107 described above, as in steps S84 to S87 of FIG. 9 according to the third embodiment, the apparatus A1 or the like in charge of the process in step S12 is transferred to the apparatus B1 or the like in charge of the process in step S14. Counting only the lots to be counted. However, since the devices A1 and B1 usually transfer the lot with other devices, the following steps S108 to S110 are similar to steps S88 to S89 of FIG. 9 according to the third embodiment. Counting is also performed for delivery of lots with devices other than the Q-Time section.

  Next, in step S108, a device group i that processes a later step in a normal process processing section (in other words, a process processing section in which no Q-Time is set) composed of two device groups, and Q A process that searches for a condition that satisfies −Time (i) ≧ Gt (i) + αt (i) and extracts all of them as a transport destination candidate is executed.

  Next, in step S109, the apparatus group i having the maximum (Q-Time (i) -Gt (i) -αt (i)) is selected as the transport destination from all candidates extracted in step S108. (The apparatus group i having the smallest processing reservation counter Gt (i) may be selected as the transport destination). Then, a value obtained by adding the inter-process processing time Tc (i) to the processing reservation counter Gt (i) is set (stored) as a new processing reservation counter Gt (i).

  Next, in step S110, the device E (i, j) having the smallest (St (i, j) + αt (i, j)) is selected as the transport destination from the device group i selected in step S109. To do. Here, the parameter αt (i, j) is a time required until the device E (i, j) that is currently stopped due to a failure or the like can be processed, and changes every moment. Then, the conveyance of the product (lot) toward the apparatus E (i, j) is started, and a value obtained by adding the inter-process processing time Tc (i) to the processing reservation counter St (i, j) is set as a new processing reservation. It is set (stored) as a counter S (i, j) t.

  Next, in step S111, a process is performed in which the apparatus E (i, j) that has completed the process is searched from the apparatus group i selected in step S105 and all are extracted as transfer destination candidates.

  Next, in step S112, for the device E (i, j) extracted in step S111, a value obtained by subtracting the inter-process processing time Tc (i) from the processing reservation counter Gt (i) is set as a new processing reservation counter Gt ( i) is set (stored), and a value obtained by subtracting the inter-process processing time Tc (i) from the process reservation counter St (i, j) is set (stored) as a new process reservation counter St (i, j). .

  Next, in step S113, a process for determining whether or not to end the progress control process is executed. When it is determined that the progress control process should not be terminated, the process returns to step S103, and when it is determined that the progress control process should be terminated, the progress control process is terminated.

  Thus, a series of processing is completed.

  As described above, in the production management system and the production management method according to the present embodiment, the processing reservation counter Gt is obtained by counting processing reservations in a plurality of manufacturing apparatuses constituting the production line in units of lot processing time. (I) and St (i, j). Therefore, as compared with the fourth embodiment, it is possible to accurately control the progress even when the processing time for each lot differs depending on the lot size or when the apparatus fails.

  In the present embodiment, as in the third embodiment, the apparatus (A1) in charge of the process in step S12, which is the first process in the Q-Time section 24, may put all lots in first-in first-out. Alternatively, first-in first-out may be performed only for the lots that can be first-in first-out.

1 is a configuration diagram illustrating a production management system according to Embodiment 1. FIG. It is a flowchart which shows typically the flow of production of the product of the whole factory. It is a flowchart which shows typically the setting of the upper limit to the time from the process completion time of an arbitrary process to the process start time of the arbitrary processes after that process. It is a schematic diagram which shows the Q-Time area comprised from two apparatuses. 3 is a flowchart showing a flow of overall processing in the production management method according to the first embodiment. 4 is a flowchart showing detailed steps of an evaluation process in the production management method according to the first embodiment. 4 is a graph showing classification by risk in the production management method according to the first embodiment. 10 is a flowchart showing detailed steps of improvement plan calculation processing in the production management method according to the second embodiment. 10 is a flowchart showing detailed steps of a progress control process in the production management method according to the third embodiment. 10 is a schematic diagram illustrating an example of a Q-Time section in which progress control processing is performed in the production management method according to Embodiment 3. FIG. It is a schematic diagram which shows the other example of the Q-Time area in which the progress control process in the production management method which concerns on Embodiment 3 is performed. 14 is a flowchart showing detailed steps of progress control processing in the production management method according to Embodiment 4;

Explanation of symbols

  1 Precondition input information, 2 Precondition input means, 3 Database, 3a Precondition, 3b Production line evaluation result, 3c Manufacturing equipment classification result, 3d Improvement plan, 3e In-process status, 3f In-process management flag, 3g Progress control command value 4, production line evaluation means, 5 manufacturing device classification means, 6 improvement plan calculation means, 8 precondition changing means, 9 production management system main body, 10 in-process status recognition means, 11 progress control means, 12 information output means, 17 production period , 18 inter-process construction period, 24 Q-Time section, 28-29 equipment, 31-33 lots.

Claims (10)

A production management system for managing a production line in which production time is restricted by a predetermined restriction value,
Precondition input means for inputting production line preconditions relating to specifications and operating conditions of the production line;
Production comprising: a production line evaluation unit that obtains the predetermined constraint value based on the input preconditions and evaluates the production line using a ratio between the predetermined constraint value and a processing time per production unit. Management system. The production management system according to claim 1,
The production line prerequisites are:
Information on the processing capacity of a plurality of production devices constituting the production line;
A production management system including at least information regarding a waiting time when the production unit is transported between the plurality of production apparatuses. The production management system according to claim 1 or 2,
The production line evaluation means includes
Further using the ratio of the total time required to perform a predetermined process to the net time required to perform only the main body of the predetermined process, and the operating rate of a plurality of production devices constituting the production line A production management system for evaluating the production line. The production management system according to claim 1 or 2,
A production management system further comprising classification means for classifying a plurality of production devices constituting the production line according to the evaluation. The production management system according to claim 4,
A production management system further comprising precondition changing means for changing the precondition for the production line according to the evaluation. The production management system according to claim 1 or 2,
Further comprising a counter for holding processing reservations in a predetermined unit in a plurality of production apparatuses constituting the production line;
A production management system for selecting a transport destination of the production unit from the plurality of production apparatuses by comparing the processing reservation held in the counter with the evaluation. The production management system according to claim 6,
The production management system, wherein the predetermined unit is the number of lots. The production management system according to claim 6,
The production management system, wherein the predetermined unit is a lot processing time. The production management system according to claim 6,
A production management system in which the predetermined unit held in the counter is the smallest and is selected as a transport destination of the production unit. A production management method for managing a production line in which production time is restricted by a predetermined restriction value,
A precondition input step of inputting production line preconditions relating to specifications and operating conditions of the production line;
A production line evaluation step of obtaining the predetermined constraint value based on the input preconditions and evaluating the production line using a ratio between the predetermined constraint value and a processing time per production unit Management method.

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