FBK / INFN Roma, November , 17th 2009 G. Darbo - INFN / Genova 3D Sensor FBK FBK / INFN Roma, November , 17th 2009 G. Darbo - INFN / Genova

ATLAS Pixel Detector ATLAS Pixel Detector: 3 Barrel Layers + 3 forward and backward disks. 1744 modules with 16 chips (27904 FE-I3 chips) – 1.7 m2 of active area

Present ATLAS Pixel Detector ATLAS Pixel Module 1744 Modules x 16 FE-I3 chips 16.8x60.4 mm2 Sensor n-in-n oxygenated 1x1015 neqcm-2 FE-I3 0.13µm CMOS 3.5 million transistors

ATLAS Pixel Pictures Bi-stave with 26 modules Layer2 half shell

ATLAS Upgrade Plans: IBL Add a new layer of Pixel inside the present three layers of the detector: 14 staves with 16 (or 32) double (single) chip modules. Prototype 2010, production 2011÷12 FE-I4 chip: ~2x2 cm, 250x50 µm pixel size New FE-I4 Pixel size = 250 x 50 µm2 Pixels = 80 x 336 Technology = 0.13µm Power = 0.5 W/cm2 FE-I3 active 16.8mm 20.2mm ~2mm ~200μm FE-I4 ~89% Chartered reticule (24 x 32) IBM reticule ~19 mm 7.6mm 8mm active 2.8mm FE-I3 74%

FE-I4 FE-I3 not suitable for IBL ~7% inefficiency at 3.7 cm and L = 3x1034 cm-2s-1 FE-I3 works at 50 Mrad, but has major faults at 100 Mrad FEI4 design collaboration formed in 2007 between: Bonn, CPPM, Genova, LBNL, NIKHEF FE-I4_proto chip (3/08) Main analog blocks (3x4mm2) Irradiated to 200 Mrad: noise increase by 20% (ENC 100 120 with 400fF load and IAVDD=10µA/pixel) FE-I3 Inefficiency

IBL Requirements for Sensors/Electronics Requirements for IBL (sensors/electronics) IBL design Peak Luminosity = 3x1034 cm-2s-1  New FE-I4, higher hit rate Integrated Luminosity seen by IBL = 550 fb-1 Total NIEL dose (rmin=3.1cm): Φ1MeV = 3.1 x 1015 ± 30% (σpp) ± 50% (sensor damage factor) Safety factor for IBL (60%)  design for 5 x 1015 neq/cm2  more rad-hard sensors Total ionization dose (TID) > 200 Mrad ATLAS Pixel Sensor/FE-I3 designed for 1015 neq/cm2 / 50 Mrad 1MeV and TID for integrated luminosity of 1000 fb-1 Ref. Ian Dawson – ATLAS IBL General Meeting (25-26 June 09)

3D Sensors - Test Beam Jun.09 test beam: 1 ATLAS Pixel planar, 1 3D SINTEF/Stanford (full column), 2 FBK partial double columns (FBK 3EM5 has low breakdown @ 10V) For inclined tracks 3D sensors have similar efficiency and spatial resolution as planar – No Lorentz angle effect in 3D sensor Active edge (STA) show efficiency up to 5÷10µm from edge Very good collaboration between all 3D sensor producers: Two meetings (Jun’09, Sep’09) They look for collaboration more than competition: better chances for IBL of having compatible 3D design in time! Ref.: O. Rohne – Vertex 2009

Assemblies Two options: module with two FE-I4 (2x4 cm2) for planar sensors or with single FE-I4 (2x2cm2) for 3D sensors FE-I4 thickness: <350 µm (what is feasible? Prototyping with dummies) Planar sensors thickness: 200÷300 µm 3D sensor thickness: 230 ± 10 µm (are sensors with array of thin – 10 µm – columns, geometry similar to the FE-I3 tested assemblies) 3D sensor could come with support wafer bonded – how can be removed after bump-deposition?

ATLAS sLHC Upgrade For sLHC, ATLAS foresee a complete replacement of the inner detector: Replace the Pixel with a 4 or 5 pixel layers: 2 or 3 times the surface The two internal layers (3xIBL surface) will need material engineering (3D) or new technology (diamond) to sustain radiation fluence (2x1016 neqcm-2) Time scale: Prototyping: 2010÷2012 Production: 2013÷2014 (15) IF 3D Sensors are proven IBL technology, they will find their application in ATLAS & CMS at sLHC. Two layers of “new technology” pixels Silicon Pixel Detector

Advantage of 3D vs planar 3D sensor has several advantages over planar More radiation hard: electrode spacing advantageous for charge collection respect to planar More collected charge – in pixel front-end chips analog/digital crosstalk limits the lowering of threshold Low bias voltage: 150 V vs >1000 V at high radiation dose Low power: planar sensor need very low temperature to avoid thermal runaway There is no Lorentz angle effect … but the major disadvantage is a new technology Require proof of production yield When do we need prototypes for IBL? FE-I4 will be submitted in March 2010 and prototype back in June If the design is successful need sensors by mid 2010 (July) and test and irradiation in fall Is this time schedule compatible with FBK? ….