Dynamically adjusting the distribution for dispatching lot between current and downstream tool by using expertise weighting mechanism

• US 20050113955A1
• Filed: 11/21/2003
• Published: 05/26/2005
• Est. Priority Date: 11/21/2003
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chien, Wen-Chi
• Granted Patent: US 7,257,454 B2
• Time in Patent Office: Days
• US Class Current: 700/101
• CPC Class Codes: G06Q 10/06 Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
• CPC Class Codes: Y02P 90/80 Management or planning

Abstract

A system and method that prioritizes product lots for fabrication and dispatching to manufacturing equipment establishes priorities for dispatching product lots based on a criticality factor and establishes a priority for dispatching product lots to manufacturing equipment based on processing capability and the efficiency of manufacturing equipment. A computer integrated manufacturing system executes a program process that functions as a lot dispatcher and a priority factor calculator. The lot dispatcher is in communication with an order entry system to receive requests for fabrication and with a process information system to receive procedures defining which manufacturing equipment is required. A manufacturing information system provides the lot dispatcher with a criticality factor and a queue level for each piece of manufacturing equipment. Then the current group of pieces of manufacturing equipment is followed with a balanced loading.

Claims

1. A system for dispatching of at least one product lot for processing to manufacturing equipment within processing stages of a manufacturing line, said system comprising:

a lot dispatcher in communication with an order entry system to receive requests for fabrication of a product lot, in communication with a process information system to receive procedures defining which manufacturing equipment is required for said fabrication of said product lot, and in communication with a manufacturing information system to receive a status of said fabrication of said product lot, a criticality factor for each piece of manufacturing equipment, and a queue level for each piece manufacturing equipment that follows a current group of pieces of manufacturing equipment required for said product lot; and

a priority factor calculator in communication with said lot dispatcher to receive a listing of said manufacturing equipment required for said fabrication of product, said criticality factor, and said queue level, for determining a priority factor for said product lot such that each group of pieces of manufacturing equipment following said current group of pieces of manufacturing equipment has a balanced loading and said product lot is processed at an expeditious time for on-time delivery.

2. The system for dispatching of claim 1 wherein:

if groups of first following pieces of manufacturing equipment have a criticality factor of a first level, said priority factor has a first priority level, and

if groups of first following pieces of manufacturing equipment are of a first type and if groups of second following pieces of manufacturing equipment are of a second type, said priority factor has a second priority level.

3. The system for dispatching of claim 2 wherein if a magnitude of said first priority level achieves a threshold level, said product lot is immediately dispatched for processing.

4. The system for dispatching of claim 2 wherein if said second priority level achieves the threshold level, said product lot is immediately dispatched for processing.

5. The system for dispatching of claim 2 wherein:

said priority factor calculator determines said first priority factor level by the formula;

$\mathrm{KF\_}<br><br>1=\frac{\mathrm{WIP\_c}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_c}*\mathrm{PPH\_c}*\mathrm{EFF\_c}}$

where;

KF_—

1 is said first priority level for a product lot entering a group of current pieces of manufacturing equipment

WIP_c is a number of items within all product lots in a queue for the group of first following pieces of manufacturing equipment,

TOOL#_c is a number of pieces of equipment within a group of the first following pieces of manufacturing equipment;

PPH_c is an average number of items of product capable of being manufactured by said group of the first following pieces of manufacturing equipment,

EFF_c is an efficiency factor for said group of the first following pieces of manufacturing equipment.

6. The system for dispatching of claim 2 wherein:

said priority factor calculator determines said second priority level by the formula;

$\mathrm{KF\_}<br><br>2=\frac{\mathrm{WIP\_cd}+\mathrm{INPR\_cd}+\mathrm{WIP\_d}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_d}*\mathrm{PPH\_d}*\mathrm{EFF\_d}}$

where;

KF_—

2 is said second priority level for a product lot entering a current group of pieces of manufacturing equipment

WIP_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment and the group of second following pieces of manufacturing equipment,

INPR_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment which are to proceed subsequently to the group of second following pieces of manufacturing equipment,

WIP_d is a number of items within all product lots in queue for the group of second following pieces of manufacturing equipment,

TOOL#_d is number of pieces of equipment within a group of the second following pieces of manufacturing equipment;

PPH_D is an average number of items of product capable of being manufactured by said group of the second following pieces of manufacturing equipment,

EFF_d is an efficiency factor for said group of the second following pieces of manufacturing equipment.

7. The system for dispatching of claim 2 wherein if the group of first following pieces of manufacturing equipment has a criticality factor of a second level, said priority factor has a third priority level.

8. The system for dispatching of claim 7 wherein if said third priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

9. The system for dispatching of claim 2 wherein if the group of first following pieces of manufacturing equipment is not of the first type, said priority factor has a fourth priority level.

10. The system for dispatching of claim 9 wherein if said fourth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on one queue of one of the first following pieces of manufacturing equipment.

11. The system for dispatching of claim 2 wherein if the group of second following pieces of manufacturing equipment is not of the second type, said priority factor has a fifth priority level.

12. The system for dispatching of claim 11 wherein if said fifth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

13. The system for dispatching of claim 2 wherein if the group of first following pieces of manufacturing equipment is of the first type, and the group of second following pieces of manufacturing equipment is of the second type, and the group of second following pieces of manufacturing equipment has a criticality factor that is not the first level, said priority factor has a sixth priority level.

14. The system for dispatching of claim 13 wherein if said sixth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

15. The system for dispatching of claim 1 wherein said product is substrates onto which integrated circuits are fabricated.

16. The system for dispatching of claim 1 wherein said manufacturing equipment is integrated circuit processing equipment for the formation of integrated circuits upon substrates.

17. The system for dispatching of claim 1 wherein the integrated circuit processing equipment includes furnaces and substrate cleaning equipment.

18. A method for dispatching of at least one product lot for processing manufacturing equipment within processing stages of a manufacturing line, said system comprising the steps of:

receiving requests for fabrication of a product lot from an order entry system;

receiving procedures defining which manufacturing equipment is required for said fabrication of said product lot from a process information system;

receiving a status of said fabrication of said product lot, a criticality factor for each manufacturing equipment, and a queue level for each piece of manufacturing equipment that follows a current group of pieces of manufacturing equipment required for said product lot from a manufacturing information system;

calculating a priority factor for said product lot from a listing of said manufacturing equipment required for said fabrication of product, said criticality factor, and said queue level,

balancing of loading of each group of pieces of manufacturing equipment following said current group of pieces of manufacturing equipment from said priority factor such that said product lot is processed at an expeditious time for on-time delivery.

19. The method for dispatching of claim 18 further comprising the steps of:

setting said priority factor to a first priority level, if groups of first following pieces of manufacturing equipment have a criticality factor of a first level, and

setting said priority factor has a second priority level, if groups of first following pieces of manufacturing equipment are of a first type and if groups of second following pieces of manufacturing equipment are of a second type.

20. The method for dispatching of claim 19 further comprising the step of dispatching said product lot for processing, if a magnitude of said first priority level achieves a threshold level.

21. The method for dispatching of claim 19 further comprising the step of dispatching said product lot for processing, if said second priority level achieves the threshold level.

22. The method for dispatching of claim 19 wherein:

calculating said priority factor comprises the step of determining said first priority factor level by the formula;

$\mathrm{KF\_}<br><br>1=\frac{\mathrm{WIP\_c}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_c}*\mathrm{PPH\_c}*\mathrm{EFF\_c}}$

where;

KF_—

1 is said first priority level for a product lot entering a group of current pieces of manufacturing equipment

WIP_c is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment,

TOOL#_c is a number of pieces of equipment within a group of the first following pieces of manufacturing equipment;

PPH_c is an average number of items of product capable of being manufactured by said group of the first following pieces of manufacturing equipment,

EFF_c is an efficiency factor for said group of the first following pieces of manufacturing equipment.

23. The method for dispatching of claim 19 wherein:

calculating said priority factor comprises the step of determining said second priority level by the formula;

$\mathrm{KF\_}<br><br>2=\frac{\mathrm{WIP\_cd}+\mathrm{INPR\_cd}+\mathrm{WIP\_d}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_d}*\mathrm{PPH\_d}*\mathrm{EFF\_d}}$

where;

KF_—

2 is said second priority level for a product lot entering a current group of pieces of manufacturing equipment

WIP_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment and the group of second following pieces of manufacturing equipment,

INPR_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment which are to proceed subsequently to the group of second following pieces of manufacturing equipment,

WIP_d is a number of items within all product lots in queue for the group of second following pieces of manufacturing equipment,

TOOL#_d is number of pieces of equipment within a group of the second following pieces of manufacturing equipment;

PPH_d is an average number of items of product capable of being manufactured by said group of the second following pieces of manufacturing equipment,

EFF_d is an efficiency factor for said group of the second following pieces of manufacturing equipment.

24. The method for dispatching of claim 19 wherein calculating said priority factor comprises the step of setting said priority factor to a third priority level, if the group of first following pieces of manufacturing equipment has a criticality factor of a second level.

25. The method for dispatching of claim 24 further comprising the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said third priority level indicates that said product lot should not be immediately dispatched for processing.

26. The method for dispatching of claim 19 wherein if the group of first following pieces of manufacturing equipment is not of the first type, said priority factor has a fourth priority level.

27. The method for dispatching of claim 26 further comprising the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fourth priority level indicates that said product lot should not be immediately dispatched for processing.

28. The method for dispatching of claim 19 wherein if the group of second following pieces of manufacturing equipment is not of the second type, said priority factor has a fifth priority level.

29. The method for dispatching of claim 28 further comprising the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fifth priority level indicates that said product lot should not be immediately dispatched for processing..

30. The method for dispatching of claim 19 wherein if the group of first following pieces of manufacturing equipment is of the first type, and the group of second following pieces of manufacturing equipment is of the second type, and the group of second following pieces of manufacturing equipment has a criticality factor that is not the first level, said priority factor has a sixth priority level.

31. The method for dispatching of claim 30 further comprising the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said sixth priority level indicates that said product lot should not be immediately dispatched for processing.

32. The method for dispatching of claim 18 wherein said product is substrates onto which integrated circuits are fabricated.

33. The method for dispatching of claim 18 wherein said manufacturing equipment is integrated circuit processing equipment for the formation of integrated circuits upon substrates.

34. The method for dispatching of claim 18 wherein the integrated circuit processing equipment includes furnaces and substrate cleaning equipment.

35. An apparatus for dispatching at least one product lot for processing to manufacturing equipment within processing stages of a manufacturing line, said system comprising:

means for receiving to receive requests for fabrication of a product lot from an order entry system;

means for receiving procedures defining which manufacturing equipment is required for said fabrication of said product lot from a process information system;

means for receiving a status of said fabrication of said product lot, a criticality factor for each manufacturing equipment, and a queue level for each piece manufacturing equipment that follows a current group of pieces of manufacturing equipment required for said product lot from a manufacturing information system;

means for calculating a priority factor for said product lot from a listing of said manufacturing equipment required for said fabrication of product, said criticality factor, and said queue level,

means for balancing the loading of each group of pieces of manufacturing equipment following said current group of pieces of manufacturing equipment from said priority factor such that said product lot is processed at an expeditious time for on-time delivery.

36. The apparatus for dispatching of claim 35 further comprising:

means for setting said priority factor to a first priority level, if groups of first following pieces of manufacturing equipment have a criticality factor of a first level, and

means for setting said priority factor to a second priority level, if groups of first following pieces of manufacturing equipment are of a first type and if groups of second following pieces of manufacturing equipment are of a second type.

37. The apparatus for dispatching of claim 36 further comprising means for dispatching said product lot for processing, if a magnitude of said first priority level achieves a threshold level.

38. The apparatus for dispatching of claim 36 further comprising means for dispatching said product lot for processing, if said second priority level achieves the threshold level.

39. The apparatus for dispatching of claim 36 wherein:

the means for calculating said priority factor comprises means for determining said first priority factor level by the formula;

$\mathrm{KF\_}<br><br>1=\frac{\mathrm{WIP\_c}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_c}*\mathrm{PPH\_c}*\mathrm{EFF\_c}}$

where;

KF_—

1 is said first priority level for a product lot entering a group of current pieces of manufacturing equipment

WIP_c is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment,

TOOL#_c is a number of pieces of equipment within a group of the first following pieces of manufacturing equipment;

PPH_c is an average number of items of product capable of being manufactured by said group of the first following pieces of manufacturing equipment,

EFF_c is an efficiency factor for said group of the first following pieces of manufacturing equipment.

40. The apparatus for dispatching of claim 36 wherein:

means for calculating said priority factor comprises means for determining said second priority level by the formula;

$\mathrm{KF\_}<br><br>2=\frac{\mathrm{WIP\_cd}+\mathrm{INPR\_cd}+\mathrm{WIP\_d}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_d}*\mathrm{PPH\_d}*\mathrm{EFF\_d}}$

where;

KF_—

2 is said second priority level for a product lot entering a current group of pieces of manufacturing equipment

WIP_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment and the group of second following pieces of manufacturing equipment,

INPR_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment which are to proceed subsequently to the group of second following pieces of manufacturing equipment,

WIP_d is a number of items within all product lots in queue for the group of second following pieces of manufacturing equipment,

TOOL#_d is number of pieces of equipment within a group of the second following pieces of manufacturing equipment;

PPH_d is an average number of items of product capable of being manufactured by said group of the second following pieces of manufacturing equipment,

EFF_d is an efficiency factor for said group of the second following pieces of manufacturing equipment.

41. The apparatus for dispatching of claim 36 wherein means for calculating said priority factor comprises means for setting said priority factor to a third priority level, if the group of first following pieces of manufacturing equipment have a criticality factor of a second level.

42. The apparatus for dispatching of claim 41 further comprising means for placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said third priority level indicates that said product lot should not be immediately dispatched for processing.

43. The apparatus for dispatching of claim 36 wherein if the group of first following pieces of manufacturing equipment is not of the first type, said priority factor has a fourth priority level.

44. The apparatus for dispatching of claim 43 further comprising means for placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fourth priority level indicates that said product lot should not be immediately dispatched for processing.

45. The apparatus for dispatching of claim 36 wherein if the group of second following pieces of manufacturing equipment is not of the second type, said priority factor has a fifth priority level.

46. The apparatus for dispatching of claim 45 further comprising means for placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fifth priority level indicates that said product lot should not be immediately dispatched for processing.

47. The apparatus for dispatching of claim 36 wherein if the group of first following pieces of manufacturing equipment is of the first type, and the group of second following pieces of manufacturing equipment is of the second type, and the group of second following pieces of manufacturing equipment has a criticality factor that is not the first level, said priority factor has a sixth priority level.

48. The apparatus for dispatching of claim 47 further comprising means for placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said sixth priority level indicates that said product lot should not be immediately dispatched for processing.

49. The apparatus for dispatching of claim 35 wherein said product is substrates onto which integrated circuits are fabricated.

50. The apparatus for dispatching of claim 35 wherein said manufacturing equipment is integrated circuit processing equipment for the formation of integrated circuits upon substrates.

51. The apparatus for dispatching of claim 35 wherein the integrated circuit processing equipment includes furnaces and substrate cleaning equipment.

52. A computer integrated manufacturing system for dispatching at least one product lot for processing manufacturing equipment within processing stages of a manufacturing line, said computer integrated manufacturing system executing program processes that function as:

a lot dispatcher in communication with an order entry system to receive requests for fabrication of a product lot, in communication with a process information system to receive procedures defining which manufacturing equipment is required for said fabrication of said product lot, and in communication with a manufacturing information system to receive a status of said fabrication of said product lot, a criticality factor for each manufacturing equipment, and a queue level for each piece manufacturing equipment that follows a current group of pieces of manufacturing equipment required for said product lot; and

a priority factor calculator in communication with said lot dispatcher to receive a listing of said manufacturing equipment required for said fabrication of product, said criticality factor, and said queue level, for determining a priority factor for said product lot such that each group of pieces of manufacturing equipment following said current group of pieces of manufacturing equipment has a balanced loading and said product lot is processed at an expeditious time for on-time delivery.

53. The computer integrated manufacturing system of claim 52 wherein:

if groups of first following pieces of manufacturing equipment have a criticality factor of a first level, said priority factor has a first priority level, and

if groups of first following pieces of manufacturing equipment are of a first type and if groups of second following pieces of manufacturing equipment are of a second type, said priority factor has a second priority level.

54. The computer integrated manufacturing system of claim 53 wherein if a magnitude of said first priority level achieves a threshold level, said product lot is immediately dispatched for processing.

55. The computer integrated manufacturing system claim 53 wherein if said second priority level achieves the threshold level, said product lot is immediately dispatched for processing.

56. The computer integrated manufacturing system of claim 53 wherein:

said priority factor calculator determines said first priority factor level by the formula;

$\mathrm{KF\_}<br><br>1=\frac{\mathrm{WIP\_c}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_c}*\mathrm{PPH\_c}*\mathrm{EFF\_c}}$

where;

KF_—

1 is said first priority level for a product lot entering a group of current pieces of manufacturing equipment

WIP_c is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment,

TOOL#_c is a number of pieces of equipment within a group of the first following pieces of manufacturing equipment;

PPH_c is an average number of items of product capable of being manufactured by said group of the first following pieces of manufacturing equipment,

EFF_c is an efficiency factor for said group of the first following pieces of manufacturing equipment.

57. The computer integrated manufacturing system of claim 53 wherein:

said priority factor calculator determines said second priority level by the formula;

$\mathrm{KF\_}<br><br>2=\frac{\mathrm{WIP\_cd}+\mathrm{INPR\_cd}+\mathrm{WIP\_d}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_d}*\mathrm{PPH\_d}*\mathrm{EFF\_d}}$

where;

KF_—

2 is said second priority level for a product lot entering a current group of pieces of manufacturing equipment

WIP_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment and the group of second following pieces of manufacturing equipment,

INPR_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment which are to proceed subsequently to the group of second following pieces of manufacturing equipment,

WIP_d is a number of items within all product lots in queue for the group of second following pieces of manufacturing equipment,

TOOL#_d is number of pieces of equipment within a group of the second following pieces of manufacturing equipment;

PPH_d is an average number of items of product capable of being manufactured by said group of the second following pieces of manufacturing equipment,

EFF_d is an efficiency factor for said group of the second following pieces of manufacturing equipment.

58. The computer integrated manufacturing system of claim 53 wherein if the group of first following pieces of manufacturing equipment has a criticality factor of a second level, said priority factor has a third priority level.

59. The computer integrated manufacturing system of claim 58 wherein if said third priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

60. The computer integrated manufacturing system of claim 53 wherein if the group of first following pieces of manufacturing equipment is not of the first type, said priority factor has a fourth priority level.

61. The computer integrated manufacturing system of claim 60 wherein if said fourth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

62. The computer integrated manufacturing system of claim 53 wherein if the group of second following pieces of manufacturing equipment is not of the second type, said priority factor has a fifth priority level.

63. The computer integrated manufacturing system of claim 62 wherein if said fifth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

64. The computer integrated manufacturing system of claim 53 wherein if the group of first following pieces of manufacturing equipment is of the first type, and the group of second following pieces of manufacturing equipment is of the second type, and the group of second following pieces of manufacturing equipment has a criticality factor that is not the first level, said priority factor has a sixth priority level.

65. The computer integrated manufacturing system of claim 64 wherein if said sixth priority level indicates that said product lot should not be immediately dispatched for processing, said product lot is placed on the queue of one of the first following pieces of manufacturing equipment.

66. The computer integrated manufacturing system of claim 52 wherein said product is substrates onto which integrated circuits are fabricated.

67. The computer integrated manufacturing system of claim 52 wherein said manufacturing equipment is integrated circuit processing equipment for the formation of integrated circuits upon substrates.

68. The computer integrated manufacturing system of claim 52 wherein the integrated circuit processing equipment includes furnaces and substrate cleaning equipment.

69. A data retention medium readable by a computer system containing a program coding for a program process for processing to manufacturing equipment within processing stages of a manufacturing line, said program coding executable by said computer system and said program process comprising the steps of:

receiving requests for fabrication of a product lot from an order entry system;

receiving procedures defining which manufacturing equipment is required for said fabrication of said product lot from a process information system;

receiving a status of said fabrication of said product lot, a criticality factor it for each manufacturing equipment, and a queue level for each piece of manufacturing equipment that follows a current group of pieces of manufacturing equipment required for said product lot from a manufacturing information system;

calculating a priority factor for said product lot from a listing of said manufacturing equipment required for said fabrication of product, said criticality factor, and said queue level,

balancing the loading of each group of pieces of manufacturing equipment following said current group of pieces of manufacturing equipment from said priority factor such that said product lot is processed at an expeditious time for on-time delivery.

70. The data retention medium for dispatching of claim 69 wherein said program process further comprises the steps of:

setting said priority factor to a first priority level, if groups of first following pieces of manufacturing equipment have a criticality factor of a first level, and

setting said priority factor to a second priority level, if groups of first following pieces of manufacturing equipment are of a first type and if groups of second following pieces of manufacturing equipment are of a second type.

71. The data retention medium for dispatching of claim 70 wherein said program process further comprises the step of dispatching said product lot for processing, if a magnitude of said first priority level achieves a threshold level.

72. The data retention medium for dispatching of claim 70 wherein said program process further comprises the step of dispatching said product lot for processing, if said second priority level achieves the threshold level.

73. The data retention medium for dispatching of claim 70 wherein:

calculating said priority factor comprises the step of determining said first priority factor level by the formula;

$\mathrm{KF\_}<br><br>1=\frac{\mathrm{WIP\_c}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_c}*\mathrm{PPH\_c}*\mathrm{EFF\_c}}$

where;

KF_—

1 is said first priority level for a product lot entering a group of current pieces of manufacturing equipment

WIP_c is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment,

TOOL#_c is a number of pieces of equipment within a group of the first following pieces of manufacturing equipment;

PPH_c is an average number of items of product capable of being manufactured by said group of the first following pieces of manufacturing equipment,

EFF_c is an efficiency factor for said group of the first following pieces of manufacturing equipment.

74. The data retention medium for dispatching of claim 70 wherein:

calculating said priority factor comprises the step of determining said second priority level by the formula;

$\mathrm{KF\_}<br><br>2=\frac{\mathrm{WIP\_cd}+\mathrm{INPR\_cd}+\mathrm{WIP\_d}}{\mathrm{TOOL}<br><br>\#<br><br>\mathrm{\_d}*\mathrm{PPH\_d}*\mathrm{EFF\_d}}$

where;

KF_—

2 is said second priority level for a product lot entering a current group of pieces of manufacturing equipment

WIP_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment and the group of second following pieces of manufacturing equipment,

INPR_cd is a number of items within all product lots in queue for the group of first following pieces of manufacturing equipment which are to proceed subsequently to the group of second following pieces of manufacturing equipment,

WIP_d is a number of items within all product lots in queue for the group of second following pieces of manufacturing equipment,

TOOL#_d is number of pieces of equipment within a group of the second following pieces of manufacturing equipment;

PPH_d is an average number of items of product capable of being manufactured by said group of the second following pieces of manufacturing equipment,

EFF_d is an efficiency factor for said group of the second following pieces of manufacturing equipment.

75. The data retention medium for dispatching of claim 70 wherein calculating said priority factor comprises the step of setting said priority factor to a third priority level, if the group of first following pieces of manufacturing equipment has a criticality factor of a second level.

76. The data retention medium for dispatching of claim 75 wherein said program process further comprises the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said third priority level indicates that said product lot should not be immediately dispatched for processing.

77. The data retention medium for dispatching of claim 70 wherein if the group of first following pieces of manufacturing equipment is not of the first type, said priority factor has a fourth priority level.

78. The data retention medium for dispatching of claim 77 wherein said program process further comprises the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fourth priority level indicates that said product lot should not be immediately dispatched for processing.

79. The data retention medium for dispatching of claim 70 wherein if the group of second following pieces of manufacturing equipment is not of the second type, said priority factor has a fifth priority level.

80. The data retention medium for dispatching of claim 79 wherein said program process further comprises the step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said fifth priority level indicates that said product lot should not be immediately dispatched for processing.

81. The data retention medium for dispatching of claim 70 wherein if the group of first following pieces of manufacturing equipment is of the first type, and the group of second following pieces of manufacturing equipment is of the second type, and the group of second following pieces of manufacturing equipment has a criticality factor that is not the first level, said priority factor has a sixth priority level.

82. The data retention medium for dispatching of claim 81 wherein said program process further comprises step of placing said product lot on the queue of one of the first following pieces of manufacturing equipment, if said sixth priority level indicates that said product lot should not be immediately dispatched for processing.

83. The data retention medium for dispatching of claim 69 wherein said product is substrates onto which integrated circuits are fabricated.

84. The data retention medium for dispatching of claim 69 wherein said manufacturing equipment is integrated circuit processing equipment for the formation of integrated circuits upon substrates.

85. The data retention medium for dispatching of claim 69 wherein the integrated circuit processing equipment includes furnaces and substrate cleaning equipment.