MPE-EM Workshop The assembly workshop S. KaufmannJune 16, 2016

MPE-EM Assembly Workshop Mission and resources Standard process Non standard processes Expertise Rework of irradiated assemblies Invoicing Future developments

Mission and resources The mission of the workshop is to provide CERN-wide resources to mount prototypes and unusual assemblies 3 CERN staff, 1 TTE  Machines programing and assembly documentation editing  Prototype assembly and repair work  Technical support for users On request, temporary personnel to face workload peaks or staff leave 2 apprentices each year  Part of the internal training of CERN apprenticeship policy

Standard processes Prototype assembly Solderpaste deposition Automated pick and place Manual component placement and insertion Reflow oven Cleaning machine Optical inspection systems Rework and modification equipment for through hole and surface mounted technologies Through industrial machines matching with the required flexibility

Standard processes capabilities Assembly Board size up to 500 x 500mm Components down to 0201 resistor/capacitor chips Component pitch down to 0.4mm Lead containing, leadfree or mixed soldering Rework and modification Board size up to 500 x 500mm on BGA repair station Components down to 0402 resistor/capacitor chips All BGA’s packages available Most of the QFN/LGA packages available Component with pitches down to 0.5mm

Standard processes

Inspection Regular production: Mantis for direct visual inspection Tagarno for video visual inspection and photo Optilia for BGA side view visual inspection When required Non destructive inspection (X-Ray, SAM, etc) Metallurgical analysis (XRF, SEM/EDX, etc) Through contacts with other CERN services or external firms

Rework tools BGA repair station TH/SMD rework tools

A look at part size 1206 Chip 0201 Chip 0402 Chip 0603 Chip 0805 Chip NINO 0.3mm solderwire 0.4mm soldering tip

Fast track assembly and rework Urgent assemblies Ability to handle 1 to 2 fast track jobs per week, depending on the complexity of the assembly Rework and modification service Ability to handle most of rework/modification on an individual board within the current day  Flexibility in resources and scheduling

Non standard processes BGA reballing, exotic package balling Special soldering alloy assembly Detector assembly MPGD/GEM Soldered silicon pixels Other user defined experiment specific assemblies Special substrate material (ceramic, metal core PCBs, etc)

Non standard assembly examples NINO chips SIPM detector 3 balled PCB stack

Non standard assembly examples 100um thick Medipix detector requiring balling of the PCB

Non standard assembly examples Connector contacts soldered on a 50um thick LCP substrate

Expertise MPE-EM has experience and provides expertise in assembly related failure analysis Failures seen on outsourced or in-house built assemblies Failures on outsourced assemblies handled directly by a customer  Specific auditing has been done by the EM team at the subcontractor  Corrective actions have been defined and deployed at the subcontractor’s place Regular issues seen:  Improper assembly process control (soldering defects)  Improper part/PCB sourcing (counterfeit parts, PCB quality issues)  Non complying design (parts impossible to assemble without specific processes, pad design leading to soldering issues)

Expertise  Direct design feedback regarding function as well as manufacturability  Direct feeding of design office with up-to-date DfM rules  Provides a double-check on DRC implemented in the design office  Allows designer to tweak their design, if required, directly in house, whatever the modification to be performed

Expertise Through its expertise in assembling exotic detector technologies  Forces to rethink assembly processes in order to adapt them to really unusual requirements  Forces to stay aware of new processes available in the industry as the use of edge packaging technologies is common  Reminds us of what are the benefits of following proper DfM rules

Rework of irradiated material Bldg 867 is dedicated to work on irradiated material TE-MPE-EM has set up in 867-R-P45 a repair workshop for the electronics community at CERN, with dedicated areas for CERN users having electronics in exposed areas Only 20% of the responders to the survey knew about this facilities, 80% intend to use it in the forthcoming 2-3 years

867-R-P45 layout

867-R-P45 processes Same rework processes available as in the assembly workshop BGA rework Chip removal/replacement Wired modifications Same inspection systems are available Direct visual inspection Video visual inspection BGA visual inspection

Invoicing Average hourly cost of 70.- to 90.- CHF depending on the task. Includes consumables, non-recurrent costs (set-up, programming, etc..), TTE and temporary personnels. Regular jobs cost based on a general calculation table, the price has been proved similar to the industry for a similar job. Repair and special works invoiced on the spent time Jobs <100.- CHF not invoiced

Future developments Implement inspection and testing tools ? The focus has been set on making quality (process control) rather than verifying it a posteriori. All these tools require additional resources for programming, running and analyzing their output. AOI, Flying probe or In-Circuit testers:  production testers, verify that the correct component is at the right place and properly soldered  a specific program for each board, to be fine tuned on batches to find the correct acceptance limits for each component and solder joint X-Ray:  provide solder joint verification for BGA and LGA  mainly used to confirm a failure but does not help preventing defects

Future developments Install additional processes Conformal coating Has been installed in 2014 for a specific requirement (DQYP), should be part of the workshop processes in B107 Adds constraints to DfM Components MSL management Humidity sensitive components should be packed and stored in ad’hoc conditions Such components are part of those supplied by the final user. MPE-EM do not store them but bakes them before mounting Today, a components repackaging equipment is available by EP-ESE, (vacuum sealing + humidity control) It makes sense that EM provides this service in its standard processes. To be programmed in the forthcoming months. Users shall setup additional measures to complete this process Alternative cleaning options The current cleaning process installed in the workshop is semi-aqueous This process showed its limits when requiring a 100% residue free cleaning (application with no leakage current allowed) or when using silicon detectors with thin aluminum substrate (Al gets corroded by the cleaning agent) An alternative option is available by the PCB manufacturing workshop and we are currently looking for another alternative to be installed in the workshop

Thank you for your attention Questions?