Wire Bonding and Analogue Readout ● Cold bump bonding is not easy ● Pixel chip is not reusable ● FE-I3 is not available at the moment ● FE-I4 is coming -> 2 readout versions: Old (no spares) Temporary (many changes, limited maintenance) ● Reduced data set (TDAQ = demonstrator / production tool) Instrument for research is needed Page 1

Signal Routing for the Wire Bonding column-wise using M2 (original proposal) signal wires must not extend beyond the guard ring ● 0 < cluster size < 400 um – readout every 8th pixel ● Minimum 8 bond pads / span (300 um) -> staggering Page 2

row-wise: ● Better solution for the AC readout ● Constant pitch for the bonding pads ● M2 / Poly could be used (RD-50) odd channels are read out from the left side, even channels – from the right side Signal Routing for the Wire Bonding ● Signal traces are orthogonal to the bias line to reduce parasitic effects ● 50 um pitch between signal traces reduces the inter-channel X-talk Page 3

Analogue Readout aLiBaVa (Beetle V1.5) H1(APC128 PSI 19) Readout chip is usually designed for the AC coupling of strip sensors - it usually tolerates high detector capacitance - should tolerate high leakage current (typical limit ~500nA -> pixels in parallel after 10e+15 N/cm^2) stand-alone system based on the USB interface VME-based: uses FADC+RIO2 Page 4

Geometry: N rows, M columns N rows = 128 (ASIC's readout channels) = 160 (compartible with the FE-I3) M columns =14 (7 pixels in parallel) - Max: should not be too high (limited by leakage current) - Min: the bias ring should be outside the FE-I3 dice (7.4 mm) 160 x 14: 128x14 pixels with wire bond pads, readout by FE-I3 / Beetle 32x14 pixels without wire bond pads, readout by FE-I3 only 160x4 FE-I3 channels without C-load good configuration for the noise studies Sensor size corresponds to 160x18 pixel matrix (FE-I3), Wire bond pads are placed instead of 2 outer column pairs. Page 5

Design Variances AC-coupling: M1 is needed as a field plate & for bump bonding M1-M2 (0.1 fF/um^2) 24 um x 350 um -> 1 pF similar to the pixel capacitance of 0.4 pF, but not a problem: Xc Mhz) ~ 10 k << Rbias Punchthrough biasing: ● p-spray only to form a conductive channel ● p-spray + p-stop (smearing of implants is critical for proper work) a.) to be simulated in TCAD b.) “efforts and failures” Page 6 Guard rings: CMS: variable distance, constant width ATLAS: variable width & distance

Hybridisation replaceable sensor ● Optimisation of the sensor size (NxM pixels) to finish the PCB design ● Design tool: Eagle Light (freeware), PCB ~60 Eur (inc. components) ● Need help with manufacturing of pitch adapters (PA) ASICs are “stationary” - could be calibrated to a high precision - same conditions for all measurements Board/ Page 7

Pitch Adapter 1 chip -> 10 sensors (PA only) -> 190 sensors (PA + patch) -> 3610 (PA + 2 patches) ● Aluminium on glass substrate ● saw or laser cut ● to be produced by CNM capacitance ~ 0.3 pF / cm Page 8

Applications ● Charge collection measurements using Beta-source: Beam Test EUDET package: ● Monoenergetic MIPs ● Trigger, Telescope ● Magnetic field, Cooling & lunches... ● Charge sharing ● Geometric efficiency ● Spatial resolution Page 9 let's make friends !

Summary Page 10 Our research requires some standard framework that we offer: Technology proof: Compare foundries using the “standard” geometry competition = compartmentalisation (risk management) Planar sensor design: Process engineering / Layout features collaboration = knowledge database, common structures