Two versions went for manufacture – test vehicle for tab and solder resist evaluation Trying to improve planarity of circuits Circuit build is identical to the electrical version – when submitted 3 layers, 18µm Cu using 50µm dielectric (polyimide) with 150µm blind vias Circuits identical except for use of differing solder resists: One batch made with ‘standard’ rigid resist (as presently used on ABCN-25 hybrids) Second batch made with flexible resist Received 5 panels of each – 80 circuits total (40 of each flavour) Quality looks very good Panels and hybrids are very flat and first pass with tooling shows nothing untoward Anecdotal evidence to suggest that shrinkage control has further improved Comes from trying tooling – will confirm their geometry next week on SmartScope Hybrid thickness is ~265µm and weigh 1.30g Present ABCN-25 hybrids come in at ~260µm and weigh 1.65g Build thicknesses similar due to use of 18/50/18 Cu-Clad carriers on new circuits ‘Old’ hybrids used thinner carrier for outer layers but 18/50/18 for inner layers 3 layer build contributes to weight reduction (less Cu) 1 ABC130 Thermo-mechanicals

HCC heat load Digital Thermometer NTC On-hybrid temperature monitoring using either 1-wire digital thermometer (DS18B20, -55ºC to +125ºC range with 12 bit resolution) NTC (1kΩ at 25ºC) Both circuits accessible via bond field towards end of hybrid Resistive elements used to emulate asic heat loads Embedded trace for ABC130 - leaves lands clear for dummy asic placement (tooling evaluation) Design specification was ~230mΩ /asic Measured resistance is higher – see next slide SMD resistors for HCC One circuit evaluated using thermal imaging camera – looked very uniform Tim Jones has data...

3 ABC130 Thermo-mechanicals Flexible Resist Standard Resist Flexible Resist Standard Resist Resistance measured for 8 hybrids (80 asics)Resistance measured for all hybrids Clearly 2 families of resistance Both batches processed at differing times No evidence of over-etching, difference probably due to differing Cu weights Expected resistance ~280mΩ/asic, measured: Standard resist: ~364mΩ/asic (σ ~ 3.67mΩ) Flexible resist: ~400mΩ/asic (σ ~ 3.75mΩ) ‘asics’ linked up serially (likewise hybrids...) For ~5W dissipation/module will require ~6V/module and ~80V/Stave side Within the “Extra Low Voltage” regime for safety (<120V DC) ~1% spread