1. Armand Usher Electrical Engineer Intel Electronics Kiriat Gat Israel
Voltage sags-solutions in semiconductor industry
Armand Usher
Electrical Engineer
Intel Electronics
Kiriat Gat Israel

2. Voltage sags in semiconductor industry
In the semiconductor industry facilities (FABs) the “voltage sags” or “voltage dips” (in British English) are the most common power problem and cause downtime, scrap and M$ losses.
SAG – voltage drop below 90% of the Un ,but not interruption
Causes - Weather conditions ,equipment failure, operation errors

3. Voltage sags in semiconductor industry
ΔU=35.8%Un
Phase
Start Time
Duration (s)
Value (V)
Deviation
Voltage Sag 2
15/09/2014 5:17:32.441AM
0.079
59600
35.83%
64.12%
Interpretation
161 KV 1Ph sag 35% → 22 KV 2 Ph sag 20% → 0.4 KV 3Ph sag 12%

4. Voltage sags in semiconductor industry
3 Ph Sc

5. Voltage sags in semiconductor industry
Source Intel Fab 28A XFMR MVA 161/22KV Dec 2012 –Dec 2013

6. Voltage sags in semiconductor industry
Affected systems:
•Instrument and controller power supplies
•VFD –variable frequency drives
•Voltage monitoring relays
•Circuit breakers open due to increased current on phases without sags
•Sensor faults or errors
•Robot failure
•Internal communication errors
•Computer re-boots

7. Voltage sags in semiconductor industry
SOLUTIONS
1 IEC performance improvement
2 Increase the voltage sags immunity for equipment's and tools
3 Install DVR (Dynamic Voltage Restorer)
4 SEMI F47 standard

8. Voltage sags in semiconductor industry
SOLUTIONS
1 IEC performance improvement
In 1999 were registered about 200 events from IEC supply grid
In 2013 were registered about 100 events

9. Voltage sags in semiconductor industry
2 Increase the voltage sags immunity for equipment's and tools
Switch power supply settings
Increase the rating of power supply unit (PSU)
Reduce the load in the power supply unit(PSU)
Use 2 Phase PSU instead of one phase
Use 3 phase PSU
Change the voltage relays settings (threshold and trip delay)
Use contactors instead of relays were possible
VFD calibration instead of scalar to set DFC (direct fly start) were flying start is automatic

10. Voltage sags in semiconductor industry
3 Install DVR (Dynamic Voltage Restorer)
The DVR purpose to compensate loss of power during voltage sags
The energy is provided by a capacitors bank
Intel DVR statistic
Two DVRs –rated power of one DVR 15/22MVA
Concept : DVR at Off line mode Vs UPS at On line mode
15 years in service
DVR availability 99.9%
Average voltage compensation /year 120
DVR external/internal compensation rate 99.5%
Compensation for 1Ph sags– 50% , for 500msec
Compensation for 3Ph sags– 35% , for 500msec

11. Voltage sags in semiconductor industry

12. Voltage sags in semiconductor industry
DVR

14. After DVR compensation on 22KV
Voltage sags upstream DVR on 161KV
161/93KV ΔUn=35%
22/12.7KV ΔUn=2.9%
After DVR compensation on 22KV

15. After DVR compensation
Voltage sags in semiconductor industry
Voltage sags upstream DVR on 161KV
After DVR compensation

16. Voltage sags in semiconductor industry
4 SEMI F47- Specification for Semiconductor Process Equipment Voltage Sag Immunity
SCOPE
SEMI F defines the required voltage sag tolerance for a semiconductor tool that must operate without interruption
For sags Phase to N and two Phases (not 3 Ph)
SEMI= Semiconductor Equipment and Materials International
The standard has been implemented by semiconductor tool vendors

17. Voltage sags in semiconductor industry
The primary focus for tools: Lito, Dif, Etch etc The secondary focus for utilities subsystems and components –Power supplies units –Ultrasonic generators –Computers and communication systems –Robots and factory interfaces –AC Contactor coils and AC relay coils –Chillers pumps and blowers –Variable frequency drives (VFD)

18. Voltage sags in semiconductor industry
SEMI F47 requires that tools tolerate the following voltage sags: •50% remaining voltage, 50% missing voltage, for 200 milliseconds •70% remaining voltage, 30% missing voltage, for 500 milliseconds •80% remaining voltage, 20% missing voltage for 1 second. In addition, SEMI F47 recommends, but does not require, that tools tolerate: •0% remaining voltage, 100% missing voltage, for 1 cycle •80% remaining voltage, 20% missing voltage, for 10 seconds

19. Voltage sags in semiconductor industry
SEMI F
Equipment will continue to operate
Equipment not required to operate

20. Voltage sags in semiconductor industry
F28A VOLTAGE SAGS vs SEMI -F47 STANDARD

21. Voltage sags in semiconductor industry
Bibliography:
-Intel F28 DVR ABB Switzerland-Maintenance manual
-Intel F28 Elspec- Investigator manual
-SEMI F and IEC Voltage Sag Standards -Differences, overlaps, and similarities - Alex Mc Eachern Power Standards Lab (PSL)
-Sag immunity - Inexpensive, simple ways to increase sag immunity -Power Standards Lab (PSL)
-Voltage sag immunity standards –Pacific Gas and Electric Company –Power quality bulletin 3 -