o Towards Sensor Decision for ATLAS IBL LHCC

o Towards Sensor Decision for ATLAS IBL LHCC Upgrade session CERN, June, 14 th 2011 G. Darbo – INFN / Genova Indico agenda: • https: //indico. cern. ch/conference. Display. py? conf. Id=141306 G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011

Sensors Designs for IBL • Not enough data available to make decision on sensors Planar: need more measurement with full radiation dose 3 D: yield and production are the major unknowns Both: need adequate statistics on irradiated chip-sensor assemblies • Following discussion in the IBL community and sensor R&D collaborations, IBL Management and Institute Board decided to restrict the IBL design to two: • Planar silicon n-in-n, 200µm thickness, slim edge from Ci. S • 3 D silicon, double side, slim edge from CNM + FBK • To comply with the IBL speedup schedule: CNM/FBK wafer mask 8 SC tiles/wafer • Complete the prototype program while launching pre-production • Enough sensors (to start module production) will be ready of the selected technology when decision will be taken Wafer to be produced (2 x good tiles of IBL modules): • Ci. S: with the measured yield (good statistics available) – 6 batches of 25 wafers satisfy IBL requirements • CNM+FBK: if yield is 50% are necessary 9/10 batches. If yield is 60% are necessary 8 batches. • Pre-production started: 50 planar (Ci. S) & 50 3 D sensors (FBK + CNM) G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL Ci. S wafer mask 4 DC tiles/wafer LHCC Upgrade session, 14 June 2011 2

Sensor Review Sensor review on July 4 th and 5 th • Review committee with five ATLAS and two non ATLAS members • The IBL Institute Board with the IBL Management plans to decide on one of the two sensor technologies based on the reviewers recommendations. • Upon sensor decision, definite IBL Mo. U and IBL TDR addendum (new schedule) will be done this summer Review committee will be asked to evaluate: • Fulfilling the requirements • Look at performance, system issues, production readiness and schedule from foundries, yield and production quantities, risks and risk mitigation • Give a weighted recommendation based on the information available at the review date Review Committee: • External reviewers: Gino Bolla (CDF), Petra Riedler (ALICE) • ATLAS internal reviewers: Katsuo Tokushuku (Chair), Craig Buttar, Marko Mikuz, Sally Seidel, Wladek Dabrowski • ATLAS ex-officio: Beniamino Di Girolamo, Marzio Nessi, Phil Allport, G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 3

Sensor Requirements Sensor requirements for IBL (from TDR): • Radiation Dose: NIEL = 5 x 1015 neq/cm 2, TID = 250 Mrad Requirements from system: The target temperature for operating the IBL sensors is approximately -15 ºC, in order to minimize effects of reverse annealing on the sensors and to avoid thermal runaway • IBL design uses evaporative CO 2 cooling an titanium pipe. • The measured Thermal Figure of Merit (TFo. M) is approximately 13 [Kcm 2/W], leading to a sensor temperature of < -20ºC. See simulation in the plot below. Loaded stave temperature: -24. 4°C (0. 72 W/cm 2) Stave TFo. M ~61% TFo. M Heat transfer ~ 19% TFo. M Pressure drop ~20% Unloaded stave temperature: -39°C G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 4

Planar Sensor – Slim Edge IBL selected design the Planar n-in-n technology has → 200 μm slim edge Guard rings on p-side are shifted beneath the outermost pixels 200µm from pixel to dicing strip ~200÷ 250 µm inactive edge → least possible inactive edge Less homogeneous electric field, but charge collection after irradiation dominated by region directly beneath the pixel implant → only moderate deterioration expected Several FE-I 4 assemblies made with different thicknesses (150 & 200µm) and conservative edge (450µm). 500µm long pixels ~450µm inactive edge No IBL design. 250 µm pixels G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 5

3 D Double Side Sensors FBK and CMN have similar process n+ etched and filled from top • FBK full thru columns stopped by membrane. p-spray for pixel isolation • CNM stop etching before reaching opposite end. pstop for pixel isolation • Expected similar performance in IBL, although variations in the two processes. Same layout and column geometry in both designs • ~10µm column diameter • FBK full through, CNM column tip 15± 7µm from opposite wafer surface. • Production schedule requires aggregate production p+ etched and filled from bottom 700 nm DRIE stopping membrane FBK DRIE: Full thru columns G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL CNM DRIE: Almost full thru columns LHCC Upgrade session, 14 June 2011 6

FE-I 4 Assemblies 78 FE-I 4 single chip assemblies have been bump-bonded at IZM: • 37 with 700 µm FE-I 4 thick chips (no thinning of the wafer) • 36 with 470 µm FE-I 4 thick chips (minimum thinning without support wafer) • 5 with 150 µm FE-I 4 thick chips + 500 µm glass support (total of 660 µm including ~10 µm glue thickness) Already made assemblies with IBL sensor technologies. • Ci. S: 35 of which 10 of IBL design • CNM: 16 of which 16 of IBL design • FBK: 17 of which 9 of IBL design G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 7

Irradiation & Test Beam Test beam at DESY (4 Ge. V electrons) in February and April and at CERN now (180 Ge. V pions). Quantities we can measure at TB ü Detection Efficiency (incl. Edge Efficiency) ü Charge Collection Efficiency • Spatial Resolution ü Charge Sharing/Cluster Size • Lorentz Shift ü measured at DESY G. Darbo – INFN / Genova as function of ü Bias voltage • Threshold setting ü Incidence angle Monitoring available of: ü Leakage current ü Sensor temperature Towards Sensor Decision for ATLAS IBL Ref: J. Weingarten – IBL GM 8 June 2011 • Non irradiated and irradiated samples with proton (Karlsruhe – 25 Me. V), and neutron (Ljubljana – nuclear reactor) • Proton irradiation with devices on PCB – Low proton energy bring high TID (~750 Mrad) and ~1÷ 3 % of pixel dead in the FE-I 4 • Bare assemblies irradiated (after test on PCB) in the reactor (activated tantalum by slow neutrons - Ta-182) – reloading on PCB and wirebonding before testing LHCC Upgrade session, 14 June 2011 8

Irradiated Samples Number of Sensor samples type Design Thickness (µm) Irrad Facility Fluence (neq//cm 2) Irrad status Status 3 x Planar Slim Edge 250 Ljubljana 4. 00 E+15 irradiated lab- and beam-tested 1 x Planar Slim Edge 250 Karlsruhe 3. 00 E+15 irradiated lab- and beam-tested 1 x Planar Slim Edge 150 Karlsruhe 2. 00 E+15 irradiated lab- and beam-tested 1 x 3 D FBK-atlas 07 230 Karlsruhe 2. 00 E+15 irradiated lab- and beam-tested 1 x Planar Conservative 200 Karlsruhe 5. 00 E+15 irradiated lab-tested 2 x 3 D CNM 230 Ljubljana 5. 00 E+15 irradiated to be wire-bonded and tested 3 x 3 D CNM 230 Karlsruhe 5. 00 E+15 irradiated 1 x lab-tested 2 x to be tested 1 x 3 D FBK-atlas 09 230 Karlsruhe 5. 00 E+15 irradiated to be tested 3 x Planar Slim Edge 200 Karlsruhe 5. 00 E+15 irradiated to be tested 2 x Planar Slim Edge 200 Ljubljana 5. 00 E+15 Irrad planned for today to be wire-bonded and tested 1 x 3 D FBK-atlas 09 230 Karlsruhe 2. 00 E+15 irradiated to be tested 1 x 3 D CNM 230 Karlsruhe 2. 00 E+15 irradiated to be tested device irradiated at IBL target fluence AND with IBL design & thickness Ref: J. Weingarten – IBL GM 8/06/2011 IBL General Meeting, CERN G. Darbo – INFN / Genova 9 Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 9

Conclusions Sensor types for IBL reduced to two technologies and designs • Pre-production started for both Sensor review in place • Decision for sensors in July 2011 Irradiated and non irradiated samples of IBL “designs” available and under test Definite IBL Mo. U and TDR addendum this summer after sensor selection G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 10

BACKUP SLIDES G. Darbo – INFN / Genova Towards Sensor Decision for ATLAS IBL LHCC Upgrade session, 14 June 2011 11