News from CMS Process Quality Control

1
News from CMS Process Quality Control

• Thomas Bergauer
• HEPHY Vienna

CMS TK Week, 29.1.2003, CERN
2
Centers

• Three Process Qualification Centers

Florence Anna Macchiolo Carlo Civinini Mirko
Brianzi
Strasbourg Jean-Charles Fontaine Jean-Marie
Helleboid Jean-Laurent Agram
Vienna Thomas Bergauer Margit Oberegger
Characterization by QTC
Process stability on test structures with 9
different measurements
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Setup Configuration
Keithely 7002
Probestation
Switching box (4 multiplexers 10 x 1 1
switch. Matrix 4 x 5
49 probes 32 ch
Computer (Labview)
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Overview

• CVMOS at different temperatures
• new aluminium thickness
• (marginal) lower value on the C_ac
• jump in the rho_alu value
• Mask Problem W7b
• Inter-calibration
• DB interaction

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CVmos at different temperatures

• Just a test (Vienna coolingbox was available)
• CVmos at 5 different temperatures
• CVmos chosen because it is the simplest
  measurement
• No temperature dependence of Vfb

6
Thicker Aluminium

• 39 Teststructures from PQC Florence
• Perugia 12 (prod.week 34/02)
• Perugia 13 (03/02)
• Perugia 14 (06/02 and 23/02)

• Pisa 59 (08/02)
• Pisa 60 (24/02)

Influence to rho_Alu
Before week 20/02
after

• Average data
• before Week 20/02
• 26,09mOhms/sq.
• After week 20/02
• 14,34mOhms/sq.

• Also slightly lower C_ac value
• 17,01pF (before week 20/02) -gt
• 16,65pF (after)

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Mask Problem W7B

• Misalignment of 3 structures at the standard half
  moon
• Not able to contact with probecard in one cycle
• W7B 1440 pcs.

Cac R (Al, p, poly) Ivgcd Cint
IVbaby Rint CVdiode CVMOS IV diel
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Mask Problem W7B

• 3 structures on the standard half moon affected
• Sensor mask is OK
• Options
• new probecard design OR
• new wafer mask design

GCD
C_int
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Inter-calibration

• Circulation of 5 Teststructures
• Vienna -gt Strasbourg
• Strasbourg -gt Florence
• Florence -gt Vienna

-gt Florence -gt Vienna -gt Strasbourg (Exchange of
TS during this Tracker Week)

• Results (up to now)
• Good agreement in all measurements
• Higher Leakage current of Vienna Probecard
  causes lower R_int and higher IV_dielectric and
  GCD problems (fit)
• small differences in capacitances values caused
  by stray capacitances. (lt1pF)

10
Software

• New Software allows re-read of local files
• Up to now Stand-alone program
• Re-analyze
• Re-write XML file

Acquisition
Analysis
DB Interface
Main
Local files
Analysis
DB Interface
new

• Future
• Fully integrated into acquisition software

Acquisition
Analysis
DB Interface
Local files
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Database

• 322 teststructures successfully loaded into db
• 61 faulty
• (status 28.1.03)