Status of OGP

1
Status of OGP Module reinforcement

• Andrea Allen
• Development Technician
• DOE Review
• January 20, 2004

2
Overview of OGP

• OGP is commercial high precision (lt 1 µm)
  automated measuring machine with programmable
  pattern recognition software
• Higher precision than gantry
• Provides independent survey of modules
• Used to cross check gantry calibration

3
Status of OGP 2002

• Beginning to write programs on OGP to automate
  after cure survey.
• Programs not very repeatable
• Manually enter data from OGP into excel
  spreadsheets
• Time consuming
• Prone to data entry error

4
Status of OGP today

• Reliable and repeatable programs written for all
  assembly plates
• User friendly, only minimal knowledge of
  measurement software needed.
• Much faster than surveying on the gantry
• Can survey 3 plates, 9 modules, on OGP in 20 min,
  same 3 plates take 45 min on the gantry
• Frees gantry for production

5
New software

• Bought SmartReport software to interface with
  exiting measurement software
• Enables direct exportation of survey results into
  excel
• Eliminates possibility of data entry error
• Excel macros written to analyze data
• Automatically converts numbers from OGP coords to
  module coords
• Compares measured values to nominal values
• Creates text files that are uploaded to database

6
Broken Bonds in Transport

• Four shipments of modules from the USA to CERN
  by 3 different methods of transport
• All were damaged in similar manner
• Many broken bonds particularly between sensor
  and pitch adaptor
• Very time consuming repair work
• At UCSB we performed extreme drop tests that
  also resulted in sensor to sensor bonds being
  broken as shown above

7
Reinforcement with Sylgard

• After many studies (drop, vibration, and
  thermal), TOB and TEC modules all found to be
  fragile
• UCSB developed a reinforcement technique using
  Sylgard.
• Sylgard is a silicon based encapsulant
• Used to encapsulate ALL wire bonds on innermost
  layer of CDF
• Working temperatures 50C to 200C
• Radiation hard
• Low thermal conductivity
• Apply this material to back sides of modules at
  sensor-PA joint and sensor-sensor joint

8
Drop Test Results

• With minimal packaging we dropped the reinforced
  modules 1 meter!
• Almost all bonds broke on the control module
  (with no reinforcement)
• No obvious deterioration of bond pull strengths
  for reinforced modules

9
Automating reinforcement

• Bought small gantry and glue dispensing robot to
  automate reinforcement
• Faster and more uniform that applying by hand
• Uses static mixer to dispense glue eliminating
  air bubbles in glue
• saves time evacuating air bubbles
• Both machines are easy to program and easily
  communicate with each other

10
Glue Gantry

• Designed bracket to mount glue dispenser to
  gantry and fixture for module carriers
• Program written to dispense glue beads
• Have reinforced 17 modules
• Very fast, can reinforce 20 modules in 15 minutes
• At peak production plan on 15 modules per day
• Glue beads are very uniform

11
Conclusion

• OGP automated and results are uploaded to
  database
• Frees up gantry for production increasing our
  daily production capacity
• OGP provides more precise measurements than
  gantry
• Also provides an independent measurement of
  gantry
• Problem found with wire bonds breaking during
  transportation
• Studies found application of Sylgard beads to
  modules solves this problem
• Bought small gantry to automate reinforcement
  process
• Can reinforce modules in a minimal amount of time