1. Department of Industrial and Systems Engineering
Fab-level Preventive Maintenance Scheduling A - Fundamental thesis to express semiconductor fab -
Jin Ho Shin
Department of Industrial and Systems Engineering
KAIST, South Korea
Thursday, September 11, 2014

2. Presentation Overview
Introduction
Preventive Maintenance
Semiconductor Manufacturing Factory
Queueing Network
Fab-level PM
Fundamental Thesis
“The Queueing Network Analyzer” by W.WHITT
Decomposition with Aggregation (DWA)
“A Queuing Network Model for Wafer Fabrication Using Decomposition without Aggregation”
By Dean Grosbard, Adar Kalir, Israel Tirkel, and Gad Rabinowitz
Future works
Minho’s PM research
Autosched AP
Concluding remarks

3. Introduction Preventive Maintenance in semiconductor manufacturing
Semiconductor Manufacturing Factory
Queueing Network
Fab-level PM
Preventive Maintenance in semiconductor manufacturing
- Complex and essential than any other manufacturing system
- Need to be scheduled carefully
- Availability vs Reliability

4. Introduction Semiconductor Manufacturing Facility
Preventive Maintenance
Semiconductor Manufacturing Facility
Queueing Network
Fab-level PM
complicating stages
(2) Probing (3) Assembly or Packing (4) Final Testing
Semiconductor Manufacturing Facility
(1) Fabrication
(1) Fabrication
(2)
(3)
(4)

5. Introduction Semiconductor Manufacturing Facility, Fab
Preventive Maintenance
Semiconductor Manufacturing Facility
Queueing Network
Fab-level PM
Semiconductor Manufacturing Facility, Fab
- Complex manufacturing system
- Toolsets are linked each other
- Toolsets are affected by each other

6. Introduction Queueing Network
Preventive Maintenance
Semiconductor Manufacturing Factory
Queueing Network
Fab-level PM
Queueing Network
- Networks of queues have proven to be useful models to analyze the
performance of complex systems
- To analyze fab,
Node: Toolset / Customer: Wafer / Tools: Number of servers

7. Introduction Preventive maintenance in fab level
Semiconductor Manufacturing Facility
Queueing Network
Fab-level PM
Preventive maintenance in fab level
- Currently, PM is scheduled based on toolset
- One toolset can affect many other toolsets

8. Fundamental Thesis The Queueing Network Analyzer
QNA
DWA
QNM using DWOA
The Queueing Network Analyzer
- W.WHITT / THE BELL SYSTEM TECHNICAL JOURNAL, VOL. 62,No. 9, , November 1983 ? ?

9. Fundamental Thesis
QNA
DWA
QNM using DWOA
Deterministic routes

10. Fundamental Thesis
QNA
DWA
QNM using DWOA
Deterministic routes

11. Fundamental Thesis
QNA
DWA
QNM using DWOA
Variability of intel-arrival

12. Fundamental Thesis Decomposition with Aggregation
QNA
DWA
QNM using DWOA
Decomposition with Aggregation
- Performed well over a wide range of queueing networks
- Three basic linear operators / Superposition, Departure, Splitting

13. Fundamental Thesis
QNA
DWA
QNM using DWOA
A Queuing Network Model for Wafer Fabrication Using Decomposition without Aggregation
- Dean Grosbard, Adar Kalir, Israel Tirkel, and Gad Rabinowitz /
THE BELL SYSTEM TECHNICAL JOURNAL, VOL. 62,No. 9, , November 1983
- Bitran & Tirupati / “Splitting is the main cause of poor estimation”

14. Fundamental Thesis
QNA
DWA
QNM using DWOA
A Queuing Network Model for Wafer Fabrication Using Decomposition without Aggregation
- One stream to several operations

15. Future works Minho’s PM research - Change the 𝐶 𝑆 2 -> 𝐶 𝑆.𝐸 2
- Change the form to apply (Time-based PM, Assumption, etc.)
Autosched AP
- Simulation result for comparison
- Currently: Follow existing demo fab-simulation

16. Concluding Remarks
So far, fab-level PM optimization is not saturated topic
Targeting: Applying the 𝐶 𝑆.𝐸 2 to queueing network and find the fab-level PM optimization model during this semester
Consistently accustom to Autosched AP

17. Department of Industrial and Systems Engineering
Fab-level Preventive Maintenance Scheduling A Part1. Fundamental thesis to express semiconductor fab
Thank you!
Jin Ho Shin
Department of Industrial and Systems Engineering
KAIST, South Korea