Tape Status Probing Wire bonding and cleaning Reliability
Tape Status • Probing • Wire bonding and cleaning • Reliability WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 1
Probing • Robot working well. • Detected slightly higher resistances on three out of six TTC lines on Altaflex tapes. Confirmed by measurement of track widths. Training technician (Joe Brown) to use robot Building up stack of tapes for axial and stereo Testing co-cured tapes Universal expansion of tape (~ 2 mm) with co-cure apply scaling correction to design. Altaflex bare tapes slightly too short, need different scale factors for Altaflex and Oxford tapes. • Upgrade robot • • • Smaller heads: allow for measurement of close pads • HVIR • No testing for few weeks WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 2
Example resistance measurements Slightly larger resistance for some lines on Altaflex tapes but not Oxford tapes Measured width of these lines and they are narrower. WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 3
Length Measurements • Expansion after co-cure WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 4
Wire Bonding and Cleaning • First trails of wire bonding pull strengths on tape co-cured to carbonfibre skins gave variable quality results. • Carbon fibre not well enough supported • Cleanliness not good • More systematic approach measure wire bond pull strengths for • Laminated tape • Short sections (10 cm) tape co-cured to carbon-skins • Full stave • Cleaning • Keep tapes cleaner avoid release agent in co-cure and use “Teflon” on pipe. • Try plasma cleaning. WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 5
Reliability • Tape co-cured to carbon-fibre skin • Test PCB mounted in Eo. S region to fan-out lines to connector. • Wire bonded at RAL. • Tape to Eo. S • s/c data and TTC lines at end to allow continuity testing • Peter Phillips has Agilent switching matrix and DVM available • Ordered Sylgard 186 potting compound for feet of wire bonds … • Measure continuity during thermal cycling in “coffin” at QM. WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 6
WP 4 F 2 F Sheffield Oct '15 Tony Weidberg 7
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