12004 SouthWest Test Workshop

Power Delivery Challenges of High Power Delivery Challenges of High Power Logic Device at SortPower Logic Device at Sort

Intel Test Tooling Operations, Intel CorporationIntel Test Tooling Operations, Intel Corporation

Sayed Mobin (Sayed.h.mobin@intel.com)Kevin Zhu (Kevin.zhu@intel.com)

Inte

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AgendaAgendaPower Delivery ChallengePower Delivery Challenge๑๑ 2003 ITRS Power Trend2003 ITRS Power Trend๑๑ Power Trend of Intel® Pentium® 4 Microprocessor Power Trend of Intel® Pentium® 4 Microprocessor ๑๑ Probe Card Power PathProbe Card Power Path๑๑ Microprocessor Power DistributionMicroprocessor Power Distribution๑๑ Intel® Pentium® 4 Microprocessor Voltage DroopIntel® Pentium® 4 Microprocessor Voltage Droop

Probe Card Power Delivery ImprovementsProbe Card Power Delivery Improvements๑๑ Probe Card Power Delivery DesignProbe Card Power Delivery Design๑๑ Power Delivery Improvements on Probe Card ComponentsPower Delivery Improvements on Probe Card Components๑๑ Innovative Improvement TechniquesInnovative Improvement Techniques

Conclusion & AcknowledgementConclusion & Acknowledgement

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Probe Card Power Delivery Challenges

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Power Trend Power Trend

Voltage is decreasing, Current & Power is increasingVoltage is decreasing, Current & Power is increasing

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

Year

Volta

ge (V

)

50

100

150

200

250

300

350

Pow

er (W

)

Core Vdd (V) Power (W)

Source: 2003 ITRS Roadmap

I_max: 124 A I_max: 430 A

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Intel® Intel® Pentium® 4 Microprocessor Power Pentium® 4 Microprocessor Power TrendTrend

Within Within Intel® Intel® Pentium® 4 generation power increases by 30 Pentium® 4 generation power increases by 30 Watts and Current increases by 30 AmpsWatts and Current increases by 30 Amps

Source: www.tomshardware.com

50

55

60

65

70

75

80

85

90

95

100

2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6Frequency (GHz)

Pent

ium

® 4

_Pow

er (W

)

20

25

30

35

40

45

50

55

60

65

70

Pent

ium

® 4

_Icc

(A)

Pentium® 4_Power Pentium® 4_Icc

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Probe Card Power PathProbe Card Power PathATE Power Supply

PCB

Top-side Stiffening Hardware

DIE (DUT)

Contact Probes

Space TransformerX

Y

Z

Power Supply

PCB Space x-former

Probes Cres

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The problemThe problemPath inductance and resistance are the main contributors to powePath inductance and resistance are the main contributors to power r path voltage drooppath voltage droop๑๑ L*di/dtL*di/dt๑๑ IR droopIR droop

An Example (Impact of Contact Resistance) An Example (Impact of Contact Resistance) ๑๑ Icc: 65 AmpsIcc: 65 Amps๑๑ Cres: 0.5 Ohms per probeCres: 0.5 Ohms per probe๑๑ Vcc probes: 400Vcc probes: 400๑๑ Total Cres: 1.25 mOhmTotal Cres: 1.25 mOhm๑๑ IR droop=1.25x65=81.25 mVIR droop=1.25x65=81.25 mV๑๑ Remaining Resistance will contribute to more IR voltage droopRemaining Resistance will contribute to more IR voltage droop

Failure to address power delivery challenge at sort is considereFailure to address power delivery challenge at sort is considered a d a serious risk as it could lead to undesirable or unpredictable soserious risk as it could lead to undesirable or unpredictable sort rt resultsresults

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Intel® Intel® Pentium® 4 Microprocessor Pentium® 4 Microprocessor Power MapPower Map

MON1 MON2

MON5

MON3

MON4

>10x Power Delta

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NonNon--Uniform Power DistributionUniform Power Distribution

MON1 MON2 MON3 MON4 MON5

Vcc_nominal

6% of Vcc

Memory Area

Core Logic Area MON1

MON2

MON3

MON4

MON5

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Intel® Intel® Pentium® 4 Microprocessor Voltage Pentium® 4 Microprocessor Voltage DroopDroop

11stst Voltage DroopVoltage Droop

Vcc_nominal

Measured 1st Droop ≈ 16% of Vcc

Simulated 1st Droop ≈ 17% of Vcc

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Intel® Intel® Pentium® 4 Microprocessor Voltage Pentium® 4 Microprocessor Voltage DroopDroop

Vcc_nominal

Measured 2nd Droop ≈ 5% of Vcc

Simulated 2nd Droop ≈ 6% of Vcc

22ndnd Voltage DroopVoltage Droop

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Probe Card Power Delivery Improvements

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Traditional Probe Card Power Path Traditional Probe Card Power Path DesignDesign

Minimize power path inductance & resistanceMinimize power path inductance & resistance๑๑ Use power planes & Vias only for high current power path design Use power planes & Vias only for high current power path design to to

minimize power path L & R (no routing)minimize power path L & R (no routing)๑๑ Reduce probe L & R Reduce probe L & R ๑๑ Reduce Space Transformer (ST) L & R Reduce Space Transformer (ST) L & R ๑๑ Reduce contact resistance between probe & wafer bumpReduce contact resistance between probe & wafer bump

Power path decoupling designPower path decoupling design๑๑ For high power device, we usually have two groups of decoupling For high power device, we usually have two groups of decoupling

capacitors for power deliverycapacitors for power deliveryLocal capacitors: on Space Transformer, closer to DUT, usually hLocal capacitors: on Space Transformer, closer to DUT, usually have relatively ave relatively small capacitance due to space constraintsmall capacitance due to space constraintBulk capacitors: on PCB with relatively large amount of capacitaBulk capacitors: on PCB with relatively large amount of capacitancence

๑๑ Adjusting decoupling capacitance to stable power supply is the tAdjusting decoupling capacitance to stable power supply is the traditional raditional way of power delivery designway of power delivery design

๑๑ Applying low ESL & ESR capacitorsApplying low ESL & ESR capacitors

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Probe Card Components Contribution to Probe Card Components Contribution to Power DeliveryPower Delivery

Power delivery quality is measured by “Vcc Droop” or “Load Power delivery quality is measured by “Vcc Droop” or “Load Line”Line”Probe card components contribution to VdroopProbe card components contribution to Vdroop

100%100%TotalTotal

8%8%OthersOthers

41%41%Space Transformer (ST)Space Transformer (ST)

28%28%ProbesProbes

23%23%Contact ResistanceContact Resistance

Contribution % to 1Contribution % to 1stst VdroopVdroopProbe Card ComponentProbe Card Component

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Probe Card Power Delivery Probe Card Power Delivery Improvements Improvements -- ProbesProbes

Low inductance & resistance probesLow inductance & resistance probes๑๑ In recent years, some new technologies have been introduced to In recent years, some new technologies have been introduced to

probing industry for making new probes for high power probe cardprobing industry for making new probes for high power probe cardmanufacturingmanufacturing

๑๑ Most of these new probe types have smaller size, lower inductancMost of these new probe types have smaller size, lower inductance e and resistance than conventional probesand resistance than conventional probes

๑๑ Current carrying capability per probe is a concern due to smalleCurrent carrying capability per probe is a concern due to smaller r sizesize

Fully populated probe arrayFully populated probe array๑๑ May not be achievable or affordable with conventional type of May not be achievable or affordable with conventional type of

probes due to smaller pitch, larger probe count & cost modelprobes due to smaller pitch, larger probe count & cost modelIntel is doing probe depop at Sort for logic deviceIntel is doing probe depop at Sort for logic device

๑๑ However with innovative smaller probes, fully populated probe However with innovative smaller probes, fully populated probe array will be more practical & achievablearray will be more practical & achievable

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Probe Card Power Delivery Probe Card Power Delivery Improvements Improvements –– Space Transformer Space Transformer (ST)(ST)

Improvements on STImprovements on ST๑๑ Increase ST power Via countIncrease ST power Via count

Checker board Via patternChecker board Via pattern

๑๑ Reduce ST thickness to reduce Reduce ST thickness to reduce power path impedance (L & R)power path impedance (L & R)

ST thickness reduction: ST thickness reduction: 150mil => 100mil => 50mil150mil => 100mil => 50mil

–– ST Via inductance ST Via inductance reductionreduction

–– ST Via resistance ST Via resistance reduction: proportional reduction: proportional to Via length reductionto Via length reduction

0.7nH0.7nH

50mil50mil

3.3nH3.3nH

200mil200mil

0.3nH0.3nH1.5nH1.5nH2.4nH2.4nHVia Inductance (effective)Via Inductance (effective)

25mil25mil100mil100mil150mil150milVia Length (50mil pitch)Via Length (50mil pitch)

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Probe Card Power Delivery Probe Card Power Delivery Improvements Improvements -- Capacitors & OthersCapacitors & Others

Use very low ESL & ESR capacitorsUse very low ESL & ESR capacitors๑๑ IDC CapacitorsIDC Capacitors๑๑ Array Capacitor Array Capacitor

Reduce contact resistanceReduce contact resistance๑๑ Probe to wafer bump contact resistance is important to probe carProbe to wafer bump contact resistance is important to probe card d

power delivery quality, higher contact resistance will result inpower delivery quality, higher contact resistance will result in a a bigger Vdroopbigger Vdroop

Improve tester power supplyImprove tester power supply๑๑ Reduce tester power supply response timeReduce tester power supply response time๑๑ Reduce power cable impedanceReduce power cable impedance

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Probe Card Power Delivery Probe Card Power Delivery Improvements Improvements -- Innovative Innovative Improvement TechniquesImprovement Techniques

Active power regulation on probe cardActive power regulation on probe card๑๑ GHz Voltage Regulation Device on STGHz Voltage Regulation Device on ST๑๑ VRM Card on PCBVRM Card on PCB๑๑ Voltage Regulation Circuit on PCBVoltage Regulation Circuit on PCB

Simulation of Vdroop improvement with & without Voltage Regulator

1st Vdroop improvement ≈ 30%

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Conclusion & Acknowledgement

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ConclusionConclusion

In general, Microprocessor power consumption is In general, Microprocessor power consumption is going up and Voltage is going down, which creates a going up and Voltage is going down, which creates a bigger challenge for power deliverybigger challenge for power delivery

Traditional power path design and improvements will Traditional power path design and improvements will be limited by physical & electrical constraintsbe limited by physical & electrical constraints

Innovative power delivery techniques are in need for Innovative power delivery techniques are in need for future probe card power delivery designfuture probe card power delivery design๑๑ Probe card suppliers should work on innovative solutions for Probe card suppliers should work on innovative solutions for

next generation high power devicesnext generation high power devices

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AcknowledgementsAcknowledgements

We want to thank our colleagues Eric Moret, Jun We want to thank our colleagues Eric Moret, Jun Ding, Phil Wade, Tim Swettlen for their contribution Ding, Phil Wade, Tim Swettlen for their contribution to the measurementsto the measurements

We want to thank SWTW to give us this opportunity We want to thank SWTW to give us this opportunity to present our workto present our work

We want to thank all audiences for your interest & We want to thank all audiences for your interest & questionsquestions