slide 1electrical testing at ucsb -anthony affolderdoe review, january 20, 2004 electrical testing...

Electrical Testing at UCSB -Anthony AffolderDOE review, January 20, 2004

Electrical Testing at UCSB:Hybrids, Modules, & Rods

Anthony Affolder

On behalf of the UCSB testing group


Testing personnel at UCSB• Professors

Joe Incandela Claudio Campagnari

• Post-docs Anthony Affolder Patrick Gartung (UC-Riverside) Russell Taylor

• Graduate Students Steve Levy

( now post-doc @ University of Chicago)

Jim Lamb Brad Patterson

(returning this summer)

• Electrical Engineering Support

Sam Burke

• Mechanical Engineering Support

David Hale Dean White

• Undergraduates Derek Barge (B.S. Physics) Chris McGuinness Lance Simms (B.S. Physics)

Joined group since February, 2003


Testing Facilities

• High Bay (Ground floor) 97 m2

– Approximately ½ for testing Single rod assembly testing Rod burn-in station

– 8 rods at one time

• Clean Room (5th floor Physics) 32 m2

Adjacent to production area Hybrid characterization/thermal

cycling Single module quick test

– 3 test stations Module burn-in station

– 10 modules at one time


Testing Responsibilities• Hybrid Thermal Cycling

(TOB/TEC) Test after pitch adaptor wire

bonding Build/commission test stands

for FNAL/Mexico 28/day at peak rate

• Sensor IV Re-probing R&D project Will not continue during

production

• Module Quick Test (TOB/TEC R5 & R6)

Test after sensor wire bonding 15/day at peak

• Module Burn-in (TOB/TEC R5 & R6)

½ -1 day “burn-in” 15/day at peak

• Final pinhole test prior to storage/rod assembly

15/day at peak

• Rod Assembly Test Build test stand for FNAL 2/day at peak

• Rod “Burn-in” 3 day “burn-in” of rods 10/week at peak

New responsibilities since February, 2003


ARCS Based Test Stands

• Hybrid testing Thermal

cycle/pulsing

• Module testing LED systems

– Pinhole/Open Tests DEPP HV supply

– Automated IV curves

3 Module test stands– 2 TOB

– 1 TEC

DEPP

LED Controller

ARC Controllers

ARCS - APV Readout Controller Software

Purpose - Fast testing of hybrids and modules

LED System

ARC FE And adaptor card


DAQ Based Test StandsDAQ system – a PC based prototype of the real CMS tracker readout chain

Purpose – fast and burn-in testing of modules and rods

Module Burn-in (Wien box)

Rod Assembly Rod Burn-in


Hybrid Testing Cycle

Ship to TEC/FNAL(13)

28 hybrids per day expected rate at peak

Wire bond PA (28)

Assemble into Modules (15) Thermal Cycle Hybrid (28)

Mount/Inspect Hybrids (28)

See L. Simms talk for details on hybrid thermal cycler


Module Testing Cycle

Wire bond (15) Module quick test (15)

Storage/Mount on Rods Thermal cycle modules (15)Pinhole tests (15)

Gantry makes modules (15)

See J. Lamb’s talk for details of rod testing


Hybrid, Module and Rod Testing Capacity

• Hybrid Capacity 28/day• Module Test ~24/day• LT Test ~20/day

½ day thermal cycles

• Rods Single rod assembly test stand being commissioned

– More experience with more rods needed– Currently developing grading criteria

With current equipment, we can assemble burn-in stand with a 2 rod capacity

– Limited by custom LV PS– Expect 2 more in the next month

Should meet near-term needs

– Working in collaboration with software developers/University of Rochester to develop/commission hardware and software needed


Major Accomplishments/Milestones

• Assembled and tested 79 high quality modules

Very low rate of introduced faulty channels

All module types built– First stereo module built/tested at

CMS

– Built/tested TEC R6 modules

• Defined grounding/shielding standards for the entire collaboration

• Wrote fault finding/categorization algorithm used by the entire collaboration

Uniformity/accuracy of testing results improved greatly

• Led in development/commissioning of module burn-in hardware/software (P. Gartung, UC-Riverside)

First fully functional and calibrated system

• Found/solved many unexpected issues with the modules

Hybrid cable breakage Module mechanical fragility Sensor quality control/variability

• Built/commissioned hybrid thermal cycler/pulser

Building 2 additional stands for FNAL/Mexico

• Assembled/tested first US rod


Faulty Channel Sources• Fault Sources (excluding cable

breaks and CMN) Hybrid-0.012% Sensor (in DB)-0.33% Sensor (not in DB)-0.19%

– Either high noise and/or visible sensor damage

Bonding-0.034%– Mostly due to early pitch-adaptors

(RMT). – No problems seen with production

pitch-adaptors (PLANAR). Testing-0.049%

– Mostly due to an early problem which has been alleviated

• Total faults – 0.63% We introduce only 0.095% bad

channels per modules on average

Fault Sources

01020304050607080

0 1 2 3 4 5 6 7 8 9 10Number of Faults

Nu

mb

er o

f M

od

ule

s

Sensor Expected

Sensor Unexpected

Bonding

Testing

UCSB Production

0

5

10

15

20

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Total number of faults (excluding CMN)

Nu

mb

er

of

Mo

du

les

Grade A Grade B Grade C


Module Testing Protocol• Module testing has matured greatly with the production of >50

modules A minimum set of tests was defined

– Using ARCS software/hardware Fault finding algorithms are now tuned to maximize fault finding and fault

type identification, while minimizing false bad channel flagging

• Noise performance and shielding standardization has allowed for the same fault finding algorithms to work on the TIB, TEC & TOB modules

Minimize the effects of external noise sources Results can be combined for the same module type measured at different

sites in order to further refine testing

• Testing procedures are now almost automated Work to automate testing fault finding module grading database

entry underway– Great collaboration with Aachen (ARCS software/hardware developer)


Fault Finding Using ARCS (1)

Noisy

1 sensor open

2 sensor open

Pinholes

Bad Channel Flags

Noise Measurement Pulse Height Measurement (Using Calibration Pulse)

Bad Channel Flags

Shorts

Pinhole

Opens


Fault Finding Using ARCS (2) Pinhole Test (Using LED System)

LED Intensity

Cal

ibra

tion

In

ject

ion

Res

pon

sePinhole

Average Subtracted Peak Time (Calibration Pulse)

1 sensor open

2 sensor open

Pinholes

Channel

Ave

rage

Sub

trac

ted

Pea

k T

ime

(ns)

Bad Channel Flags


Fault Finding Using ARCS (3) • Test failures are correlated in order to

diagnose fault type Open (1 or 2 sensor) Short Pinhole/Saturated Channel Noisy Channels Mid-sensor opens

• Faults are found >99% with correct fault type identified ~90% of the time

Misidentification is almost always between 1 or 2 sensor opens

Less than .1% of good channel flagged as faulty

As more modules are built, fault finding criteria will be re-tuned to improve performance

Integrated into ARCS software by Aachen

• Database output of module testing is being finalized

Similar tuning of fault finding underway for DAQ-based systems

– Led by Patrick Gartung (UC-Riverside)


Test Stand Cross-calibration• All ARCS systems have had first

iteration of cross-calibrations• Modules are circulated between

testing centers Multiple examples of common

problems are added to each module

– Shorts (neighbors & next-to-neighbors)

– Opens (sensor-sensor & PA-sensor)

– Pinholes

• With new qualification standards, results nearly identical

Final iteration of cross-calibrations are currently underway

DAQ cross-calibration is forth-coming


Wien cold box• Wien cold box cycles modules from –20 C to

20 C while reading 10 modules DAQ Based System Modules cycled 1/2-1 day with ~4 cycles per

day.– Current (LV/HV), temperature, and relative

humidity continuously monitored Effort led by P. Gartung (UC-Riverside)

Torino Interlock Box

Inside Wien Cold Box

LV Distribution

Electrometers

Peltier PS

HV Power Supply

VUTRI

PAACB

Multiplexer

Backplane of Wien Cold Box


Hybrid Problem• Cable brittle at connector solder pads

Differential data output lines break

• Reported by UCSB on Sept. 4 Production was halted that week. Protective stiffener designed and studied by US

and vendor Production re-started Oct. 20

• Current schedule looks good 100 TIB hybrids delivered early Nov. 500 hybrids per week as of mid Dec.

• 4000 hybrids were in production when problem was discovered

1000 throwaways and 3000 retrofits Good collaboration/quick reaction of UCSB

and CERN groups greatly minimized number of damaged parts


CMN Problem-Sensors• 16 of 79 modules produced at UCSB exhibit large

common mode noise (one chip only)• All of the 16 modules have a larger bias current than

expected from sensor QTC probing Extremely high noise on 1-4 channels on each module suggests

all the excess current localized to these channels No obvious damage seen on these channels (visual inspection) No indication of problems seen in sensor QTC measurements

• At UCSB, problem always appeared at first test after bonding 1 module at FNAL developed problem during Wien box

module burn-in after a full ARCS module characterization


CMN problem vs. voltage

•Once, IV diverges from QTC expectations, noise on channel increases rapidly causing CMN at 20-60 V above the divergence point

•In all cases, there is no indication of noise below the divergence point or unusual leakage currents in the QTC probing

Module 1011

100

1000

10000

100000

0 100 200 300 400

Voltage

Cu

rren

t(n

A)

Sensor 1

Sensor 2

Sensor 1 +2

Module Unbonded


Are the faults caused by assembly?

Extensive program of sensor re-probing and additional module IV measurement undertaken Sensors probed prior to assembly in modules

– Sensors with >5 A extra current relative to sensor QTC measurement separated from others

Module then assembled and bias bonded to first sensor– IV measured

Bias is bonded to second sensor– IV re-measured

Module is then fully bonded and tested

• During all measurements, environment controlled Temperature between 23-24 C RH <30%


IV Correlation with CMN problems• Significant differences from QTC sensor probing have been found

~7% of sensors have current increases >5 A from QTC prior to module assembly

– Roughly consistent with the rate of occurrence of the CMN problem (micro-discharge) observed at various production sites

– The increased current occurs during ramp up during IV probing

• Production Results with IV Pre-Screening Of the 39 modules produced with sensors whose IV curves in the QTC

database matched those obtained in UCSB re-probing, only 2 showed CMN problem (5%)

– 1 module showed increased currents in some tests and regular currents in others so the problem appears to be intermittent

– Another showed CMN problem with only 0.5 A extra bias current Of the 5 modules with sensors whose IV curves in the QTC database with 5

extra A of current from those obtained in UCSB re-probing, 4 had serious CMN problems (80%)

– Rules out hypothesis that problems due to mishandling in US– Indicates any change in IV curve relative to original QTC measured a good

predictor for sensors that will cause this problem


Increased IV In Re-Probing30210420383228

100

1000

10000

100000

0 100 200 300 400

Voltage (V)

Curre

nt (n

A) Current(DB)Current(probing)

30210414845823

100

1000

10000

0 100 200 300 400 500

Voltage (V)

Curre

nt (nA

) Current(DB)Current(probing)

30210314845402

100

1000

10000

100000

1000000

0 100 200 300 400

Current (DB)Current (Probing)

30210415061806

100

1000

10000

100000

0 100 200 300 400 500

Voltage (V)

Curre

nt (n

A) Current(DB)Current(probing)


Further Activities To Solve CMN Problem

• A world-wide program of sensor re-probing underway to understand the scope of the problem

• A production run of 150 modules each at UCSB and FNAL will start shortly using the most recently produced sensors Study rate of problem, correlations with sensor probing,

and long term behavior of modules

• Began negotiation/production at an alternate sensor vendor Initial delivery of proto-types due by March


Near-Term Activity• Late January

Assemble/bond/test 150 SS4 TOB modules in a 2 week period Begin bonding/testing ~60 hybrids/week Assemble/test 2 SS4 Rods Assemble and begin commissioning of a 3 Rod burn-in test stand Deliver/commission hybrid thermal cycler at FNAL

• Early February Assembly/bond/test 50 TEC R6 modules

– Confirmation of design/commissioning of testing protocols

• Late February Assembly/bond/test 150 SS6 TOB modules in a 2 week period

• Early March Assembly/bond/test first US TEC R5 R-phi modules Assemble/test 11 Rods (9 SS4, 1 SS6, 1DS)

– Commission/design DS rod assembly tools Finish commissioning of full Rod burn-in test stand

– Assuming power supplies are available


Conclusions and Future Goals

• Very eventful year with a great deal accomplished!!! Standardization/automation of hybrid/module testing

– Will apply same techniques to rod testing/burn-in Through careful testing, discovered and solved hybrid and

module fragility problems– Will use the same program of testing in TEC R5 and R6 modules

Discovered potentially serious problem with ST sensors– Many studies underway to understand extent/severity of problem– Talks with alternative sensor vendor started

• Next year will be even more exciting Full-scale module production will begin

– Including significant increases in hybrid bonding Building/commissioning of rod assembly/burn-in systems


THE FOLLOWING SLIDES ARE BACK-UP


Man-Hours/ARCS Stand Time

Man-hours Needed ARCS Stand Time Needed

Mount/inspect hybrids ~2 ½ hours N/A

Thermal Cycle Hybrids ~3 hours N/A

Mount Module Cables ~ ½ hours N/A

Bonded Module Test ~2 ½ hours ~5-6 hours

Wien Box Test ~4 hours N/A

Pinhole Test ~2 ½ hours ~2 ½ hours

TOTAL ~14 - 15 hours (2 1/2 techs) ~7 ½ -8 ½ hours (2 stands)


Common Mode Subtracted Noise25 ADC

Module #: 869 881 1010 1011 1013 1014 1015 1016 1030 1031 1038 1042

6.5 ADC

Chips with CMN (micro-discharge problem)Common mode subtracted noise in blue

For majority of modules with problems, the CM subtraction is imperfect.7 of 12 have >2.0 ADC noise

3 of 12 have more than twice the usual noise

Off

sc

ale

Off

sc

ale


IV Test Results (UCSB)

• Environmental conditions tightly controlled Temperature 23.1-23.8 C RH < 30% at all times

• Increase as low as 0.5 A has been seen to cause CMN Better results with newer OB2 sensors (2002) 20 newer (2003) OB2 sensor show no increase in bias current

Sensors > 2 A

> 5 A

>10 A

>20 A

>100 A

< -2 A

<-5 A

<-10 A

OB2 (’00-01) 15% 9% 8% 5% 1% 8% 3% 1%

OB1 (’00-01) 6% 3% 3% 3% 3% 3% 0% 0%

OB2 (’02) 3% 3% 0% 0% 0% 2% 2% 0%

OB2 (’03) 0% 0% 0% 0% 0% 0% 0% 0%

Probed Current @ UCSB (400 V) – QTC Measurement (400 V)

slide 1electrical testing at ucsb -anthony affolderdoe review, january 20, 2004 electrical testing...

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