Method and system for dynamic dispatching in semiconductor manufacturing plants

• US 5,612,886 A
• Filed: 05/12/1995
• Issued: 03/18/1997
• Est. Priority Date: 05/12/1995
• Status: Expired due to Term

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Weng, Yi-Cherng
• Primary Examiner(s): Gordon, Paul P.
• Assistant Examiner(s): Dolan, Robert J.
• Application Number:
  US08/440,094
• Time in Patent Office: 676 Days
• Field of Search: 364/468, 364/401 R, 364/550, 364/468.01, 364/468.03, 364/468.05, 364/468.08, 364/468.07
• US Class Current: 700/101
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

A manufacturing control system uses computer control of work flow for automatic production line control. The process is to sort (Work in Process) WIP by priority and queue time; select high priority WIP; and sort WIP by queue time and batch with other WIP by the same recipe. Calculate a dynamic dispatching ranking except for high priority batch WIP. Select the high priority stage and batch the high priority stage by recipe based upon queue time management. Test whether the line remains loaded at capacity. If the line is below capacity, interrupt the method. If the line operates at capacity, then branch to recalculate the ranking. Then return to select the high priority stage and select the batch high priority stage by recipe based upon queue time management.

Claims

1. A method of operating a manufacturing control system with computer control of work flow in automatic control of a manufacturing production line by the steps in the sequence comprising,

sorting Work In Process (WIP) by priority and queue time,

selecting high priority WIP, in terms of schedule requirements, after sorting of WIP by priority and queue time,

after said selecting high priority WIP, sorting WIP by queue time and hatching with other WIP with a same recipe of process steps and process conditions,

performing DD_-- R stage calculation except for high priority batch WIP, where ##EQU12## where UT=Updated Target,

AO=Actual Out data, ##EQU13## NEG_-- WIP=Next_-- Equipment Group WIP, and EAC=Equipment Availability Capacity,

selecting a high priority stage by computer sorting, and then hatching said high priority stage by a said recipe based upon queue time management by computer sorting,

a testing step to determine whether the production line remains loaded at capacity, and

if the production line is operating below capacity, then since the dispatching system is operating below capacity the said method of operating a manufacturing control system stops,

but if the production line remains operating at capacity, then branching to recalculate the DD_-- R and then returning to the step of selecting the high priority stage and selecting the batch high priority stage by recipe of process steps and process conditions based upon queue time management followed by repeating said testing step and the steps which follow said testing step,

whereby automation of production control of a manufacturing process is provided by improved automation of work scheduling.

2. A method of manufacturing in accordance with claim 1 wherein loading is calculated as follows:

##EQU14## K=Loading, CT=Stage Process Cycle Time, and

WIP(i)=Stage work-in-process quantity.

3. A method of manufacturing in accordance with claim 2 wherein demand is calculated as follows:

##EQU15## n=total process stages, K=Loading,

CTi=stage process cycle time, and

WIP(i)=stage work-in-process quantity.

4. A method of manufacturing in accordance with claim 1 wherein (DD_-- R) is calculated as follows:

##EQU16## where UT=updated target,

AO=Actual Out data,

where NEC_-- R is the Next Equipment Capacity Satisfaction

Ratio calculated by the equation as follows;

##EQU17## NEG_-- WIP=Next_-- Equipment Group WIP, and EAC=Equipment Availability Capacity.

5. A method of manufacturing in accordance with claim 4 wherein loading is calculated as follows:

##EQU18## K=Loading, CT=Stage Process Cycle Time, and

WIP(i)=Stage work-in-process quantity.

6. A method of manufacturing in accordance with claim 4 wherein demand is calculated as follows:

##EQU19## n=total process stages, K=Loading,

CTi=stage process cycle time, and WIP(i)=stage work-in-process quantity.

7. A method of computer control of work flow in control of a manufacturing production line including the steps in the sequence as follows:

sorting Work In Process (WIP) by priority and queue time,

selecting high priority WIP, in terms of schedule requirements, after sorting of WIP by priority and queue time,

after said selecting high priority WIP, sorting WIP by queue time and batching with other WIP with a same recipe of process steps and process conditions,

performing DD_-- R stage calculation except for high priority batch WIP, where ##EQU20## UT=Updated Target, AO=Actual Out data,

where NEC_-- R is the Next Equipment Capacity Satisfaction Ratio calculated by the equation as follows;

##EQU21## NEG_-- WIP=Next_-- Equipment Group WIP, and EAC=Equipment Availability Capacity,

selecting a high priority stage by computer sorting,

then bathing said high priority stage by a said recipe based upon queue time management by computer sorting,

testing to determine whether the production line remains loaded at capacity, and

if the production line is operating below capacity, then since the dispatching system is operating below capacity said method of operating a manufacturing control system stops, but if the production line remains operating at capacity,

then branching to recalculate the DD_-- R and then returning to the step of selecting the high priority stage and selecting the batch high priority stage by recipe of process steps and process conditions based upon queue time management followed by repeating said testing step and the steps which follow said testing step,

whereby automation of production control of a manufacturing process is provided by improved automation of work scheduling.

8. A manufacturing control system including computer control of work flow in automatic control of a manufacturing production line for performing a sequence of steps,

means for sorting Work In Process (WIP) by priority and queue time,

means for selecting high priority WIP, in terms of schedule requirements, after sorting of WIP by priority and queue time,

means for sorting WIP by queue time and batthing with other WIP by same recipe of process steps and process conditions,

means for performing DD_-- R stage calculation except for high priority batch WIP, where ##EQU22## UT=Updated Target, AO=Actual Out data,

where NEC_-- R is the Next Equipment Capacity Satisfaction Ratio calculated by the equation as follows:

##EQU23## NEG_-- WIP=Next_-- Equipment Group WIP, and EAC=Equipment Availability Capacity,

means for selecting a high priority stage by computer sorting and then batching said high priority stage by a said recipe based upon queue time management by computer sorting,

means for testing to determine whether the production line remains loaded at capacity, and if the production line is not operating at capacity, then since the dispatching system is operating below capacity said sequence of steps stops; and

if the production line remains operating at capacity, then means for branching to recalculate the DD_-- R and then return to said means for selecting the high priority stage and selecting the batch high priority stage by recipe based upon queue time management,

whereby automation of production control of a manufacturing process is provided by improved automation of work scheduling.

9. A manufacturing system in accordance with claim 8 including means for calculating loading as follows:

##EQU24## K=Loading, CT=Stage Process Cycle Time, and

WIP(i)=Stage work-in-process quantity.

10. A system for manufacturing in accordance with claim 9 including means for calculating demand as follows:

##EQU25## n=total process stages, K=Loading,

CTi=stage process cycle time, and

WIP(i)=stage work-in-process quantity.

11. A system for manufacturing in accordance with claim 8 including means for calculating demand as follows:

##EQU26## n=total process stages, K=Loading,

CTi=stage process cycle time, and

WIP(i)=stage work-in-process quantity.