Marina Artuso1 Pixel notes Topics covered –Sensor –Front end electronics –Integration: Bump bonding (including roundtable featuring AMS,IZM, VTT) Multichip modules Hybrids Web page:

Marina Artuso2 Sensor Interpixel insulation: –ATLAS “moderated p-spray” –CMS “p-stop double open ring” 250  m sensors –At Elba meeting CSEM, SINTEF not too enthusiastic, CANBERRA ok 200  m –CiS produced 1 st “moderated p-spray” in 200  m –IRST (Trento, Italy) has tried to produce “p-spray” and “moderated p-spray”

Marina Artuso3 Sensor - continued Discussion with SINTEF –HERA-B sensors: moderated p-spray (3 different B doses for implantation ) Before irradiation breakdown at about 200 V (guard ring) worsened upon irradiation. Theory: p+ guard ring on the ohmic side create problem (punch through when depletion region reaches guard ring) –P-spray versus p-stop, latter easier, very important for p-spray to achieve quite smooth implantation densities + need to negotiate with MPI (design patented ?).

Marina Artuso4 ROSE collaboration results Several talks on oxygenated wafers both at ELBA (2) and at PIXEL2000 (1). Oxygenated wafers very popular. SINTEF in the ROSE collaboration & ok, CSEM had problems with the first iteration of oxygenated wafers for Horisberger, they will try again.

Marina Artuso5 Bump bonding Industry representatives: –Annamaria Fiorello – AMS, Italy (In) –Juergen Wolf – IZM, Germany (Solder) –Ikka Suni – VTT, Finland (Solder, including low melting eutectic used for an X ray pixel device with bump size 15  m on 30  m pitch –Roland Horisberger reported on PSI experience Both In and Solder seem adequate technologies

Marina Artuso6 Hybridization ATLAS specifications for flex hybrid module: - 2 metal layers –* kapton substrate, metal traces on both faces (25 micron thick) –* Copper traces: 7  m thick, 75  m minimal distance, critical issues: - wire bonds - stress induced on the bumps (different CTE) and wirebonds

Marina Artuso7 Hybridization (II) First results presented on “thin” flex- hybrid: electronics thinned down to 150  m –3 modules tested at Genova (2 bonded by AMS) –Module 2 is the best with very few dead channels and threshold 3900  260 e - and mean noise about 210 e - (however with rather long tail) (see Paulina Netchaeva’s talk).

Marina Artuso8

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