The 9 th LC-Spain meeting New detectors development

The 9 th LC-Spain meeting New detectors development at CNM-IMB G. Pellegrini Centro Nacional de Microelectrónica (IMB-CNM-CSIC) Barcelona, Spain G. Pellegrini 1

2 The 9 th LC-Spain meeting CNM Research Projects in HEP § SCTESP 4 § (M. Ullan) Coordinador Main exp. IFIC ATLAS upgrade § NEWATLASPIX 2 § (G. Pellegrini) IFAE ATLAS IBL § DET 4 HEP § (S. Hidalgo) IFCA CMS-ILC All the projects are linked by the development of new advanced detector technologies for the different applications G. Pellegrini

The 9 th LC-Spain meeting SCTESP 4 Contribution to the ATLAS Experiment Upgrade for the S-LHC Objective: Technological developments associated with the ATLAS Upgrade for the Super-LHC at CERN. Working in two fronts: On one side in the development of radiation detectors that will maintain the current performances after the increase of one order of magnitude in the luminosity at S-LHC. On the other side, in the search of suitable readout electronics for these detectors and the proper power distribution. Project ends December 2012 G. Pellegrini 3

The 9 th LC-Spain meeting Radiation hardness studies • Front-end electronics detailed technology evaluation • Proposal and full assessment of one advanced technology • Design of test chips • Ionization, displacement • Dose Rate (ELDRS) • Radiation hardness evaluation of LDMOS power devices for DC-DC power distribution • Test • Simulation G. Pellegrini 4

The 9 th LC-Spain meeting Prototype detector fabrication • For the modules prototypes of the End-Cap Inner Tracker • Addresses most of the issues that make a petal different than a stave. • Built-in stereo angle. • Different pitch. • Bonding angle. • Embedded pads. • Incomplete strips • Automatic detector layout construction tool • Sensors being fabricated for a total of 10 prototypes (60 sensors) G. Pellegrini 5

6 The 9 th LC-Spain meeting New detectors development – RD 50 • Low resistance strip sensors • Full protection vs. beam loss • Punch-Through Protection (PTP) optimization • Deposition of Aluminum on top of the implant • Combined experiment with Slim Edges (Trenches 30 um wide): • Opt 1: 10 μm deep etch • Opt 2: ~250 -280 μm deep etch • Opt 3: Xe. F 2 etch at NRL G. Pellegrini s p s d Bias rail Polysilicon “bridge/gate” Implant

The 9 th LC-Spain meeting NEWATLASPIX 2 Development and construction of pixel detectors for the IBL and s. LHC ATLAS experiment upgrades Objective: Contribute to various aspects of the development of pixel sensors for the IBL (insertable b-layer) of the ATLAS Inner Detector and the s. LHC. Project ends December 2013 G. Pellegrini 7

The 9 th LC-Spain meeting IBL Production • 50% of IBL 3 D sensors fabricated at CNM. • 255 detectors delivered to IZM for the UBM and flip chip. • Common layout within the Atlas 3 D collaboration (http: //test 3 dsensor. web. cern. ch/test-3 dsensor/). • Sensors produced for the geometry of the FE-I 4 chip: • 50 um x 250 um • 210 um columns in 230 um p-bulk • Inactive edges of ~ 200 um • Extensive characterization and testing being done at IFAE with un-irradiated and irradiated devices up to 5. 11 x 1015 neq/cm 2 G. Pellegrini 8

The 9 th LC-Spain meeting Technology: G. Pellegrini 9

The 9 th LC-Spain meeting Test-beam Results CNM devices have been tested in the CERN testbeam and have shown efficiencies >97% after irradiation (according to IBL specifications) Pixel efficiency map: fold efficiency to 1 (± 0. 5) pixel (match track in 3 x 3 pixel window) CNM 55: un-irradiated 0 deg incidence HV=20 V eff=99. 4% CNM 81: n-irradiated 0 deg incidence HV=160 V eff=97. 5% CNM 34: p-irradiated 15 deg incidence HV=160 V eff=98. 9% G. Pellegrini 10

The 9 th LC-Spain meeting Work plan G. Pellegrini 11

The 9 th LC-Spain meeting DET 4 HEP R&D on detectors for future colliders Objective: Development of new tools, technologies and techniques to bring new detector concepts to the stage where they can be considered for new or existing facilities. Project ends December 2013 G. Pellegrini 12

13 The 9 th LC-Spain meeting Silicon APDs Linear mode RT-APD N on P Reach-Through Avalanche Photodiodes § Active area: 5 × 5 mm 2 § Dice Area: 8 × 8 mm 2 § Device thickness: 300 µm N+ cathode P-type layer: Different Boron doses Different layouts with and w/o guard ring, with non-metalized windows for laser characterization P-type substrate: ρ = 5 -15 kΩ·cm P+ anode First experimental results I ~ 250 n. A @ 20 ºC G. Pellegrini VFD < 30 V VBD > 1100 V Problems to overcome 200 V for encapsulated devices

The 9 th LC-Spain meeting Thinned microstrips sensors with integrated pitch adapters • 5 wafers thinned to 100 um thick. • 6 thick wafers 285 um. • AC strip detectors, 80 um pitch. • Double metal technology to implement integrated fanout. • Detectors to be irradiated. G. Pellegrini 14

15 The 9 th LC-Spain meeting Detectors with Fiber Optic Sensors (FOS) Grooves for optical fibres Fiber Bragg grating (FBG) L. Benussi et al. , Proc. IEEE Sensors 2 (2002), 874 Optical fibre were successfully inserted and clamped Bridges Clamps 500 um Ideal candidate for present and next generation HEP detectors especially due to compactness, easy installation, high level performance, multifunctionality, expected radiation hardness and flexibility G. Pellegrini

16 The 9 th LC-Spain meeting CMS pixel detectors • 8 wafers already fabricated and tested at CNM. • PSI already bonded many devices • Detector bonded sent for irradiation at Karlsruhe and Ljubljana (Φ= 1 x 1015, 5 x 1015 y 1 x 1016 n/cm². ) Full- Module G. Pellegrini See Paki´s talk

The 9 th LC-Spain meeting What can be improved in pixel detectors for HEP or other applications? 1) Short term: slim edges 2) Long Term: thin substrates with charge multiplication G. Pellegrini 17

The 9 th LC-Spain meeting 1) Post processing for slim edges Reduce the dead area at the detector edges. Laser-Scribing and Al 2 O 3 Sidewall Passivation of P-Type Sensors. Negative charges induced by Al 2 O 3 deposited by ALD process, isolate the sidewall surface cut in p-type wafers reducing surface current. Laser cutting and ALD done at NRL Marc Christophersen Work done in the framework of RD 50 collaboration (CERN) G. Pellegrini 18

19 The 9 th LC-Spain meeting Pixel Status: AFP (TOTEM? ) Pixel detectors: technology choice in high-energy physics for innermost tracking and vertexing. 220 m to ATLAS P 1 G. Pellegrini • AFP: detect very forward protons at 220 m from IP, with pixel detectors for position resolution and timing detectors for removal of pile up protons. • Both Si and timing detectors mounted in movable beam pipe • Silicon detector has to have small dead inactive region on side into beam • Non-uniform irradiation of the detectors.

20 The 9 th LC-Spain meeting Slim edges Dicing process P-Type Silicon • Annealing of alumina layer reduces leakage current (same effect as seen for solar cells). • Formation of native oxide (wrong surface charge) ↑ leakage current. • Native oxide forms rapidly (within seconds/minutes) in air. • Native oxide: ~ 2 nm thick, high charge trap density. G. Pellegrini • Laser-scribing and cleaving common in LED industry • Automated tools for scribing and breaking of devices on wafer-scale

21 The 9 th LC-Spain meeting New samples with slim edges (Atlas FE-I 4 pixels) 55 um Laser cutting and ALD done at NRL Spare 3 D FE-I 4 detectors from IBL production done at CNM. Normally from damaged wafers. G. Pellegrini

22 The 9 th LC-Spain meeting In-Homogeneous Irradiation and Test-beam Results • AFP devices will receive an in-homogeneous irr. dose (up to 2 E 15 neq/cm 2) • Irradiation done at CERN (24 Ge. V protons) • IBL-sensors were irradiated ‘a la-AFP’ and their performance evaluated with beam • Work done with the ATLAS IBL, 3 D and AFP groups CERN 3 D Testbeam Preliminary efficiency: 98. 3% • Operated at 130 V • Beam pointing to “irradiated side” • Cooled with dry-ice (-30 C) Preliminary results for CNM(57) device G. Pellegrini S. Grinstein presented at RESMDD 12

The 9 th LC-Spain meeting Charge Multiplication- pixel detectors We are on the fabrication of new p-type pixel detectors with enhanced multiplication effect in the n-type electrodes. 3 different approaches: 1. Thin p-type epitaxyal substrates 2. Low gain avalanche detectors 3. 3 D with enhanced electric field. I am coordinating two RD 50 projects (under approval) to work on these technologies. G. Pellegrini 23

The 9 th LC-Spain meeting 1)Thin p-type epitaxyal substrates Detector proposed by Hartmut Sadrozinski and Abe Seiden (UCSC) , Ultra-Fast Silicon Detectors (UFSD). Provide in the same detector and readout chain • Ultra-fast timing resolution [10’s of ps] • Precision location information [10’s of µm] We propose to achieve high electric field is to use thin p-type epitaxyal substrates [1] grown on thick support wafers, p+-type doped, that acts as the backside ohmic contact. Different thicknesses will be used to study the multiplication effect induced by the high electric field at the collecting electrodes, depending on availability we propose to use: 10, 50, 75µm. Need very fast pixel readout. H. Sadrozinski, “Exploring charge multiplication for fast timing with silicon sensors” 20 th RD 50 Workshop, Bari 2012 G. Pellegrini 24

25 The 9 th LC-Spain meeting 2)Low gain avalanche detectors (LGAD) Crating an n++/p+/p- junction along the centre of the electrodes. Under reverse bias conditions, a high electric field region is created at this localised region, which can lead to a multiplication mechanism. High Electric Field region leading to multiplication N+ 285 um P P. Fernandez et al, “Simulation of new p-type strip detectors with trench to enhance the charge multiplication effect in the n-type electrodes” , Nuclear Instrumentsand. Methodsin. Physics. Research. A 658(2011) 98– 102. G. Pellegrini

The 9 th LC-Spain meeting 26 3) 3 D with enhanced electric field Simulation has shown that using silicon substrates with a resistivity <500 ohm*cm could induce charge multiplication at low bias voltage but still depleting the detector bulk. We are ready to start the production on SOI wafers (resistivity 100 ohm*cm) with a thickness of 50µm to fabricate 3 d thin detectors with medium or low multiplication factors before irradiations. J. P Balbuena, Simulation of 3 D detectors, 6 th Trento Workshop on Advanced Radiation Detectors, 2 -4 March 2011 FBK, Povo di Trento, Italy G. Pellegrini

The 9 th LC-Spain meeting Conclusions • Collaboration between CNM and HEP institutes is working very well. • Collaboration between “Technology” and “Physics” is very important to propose new technologies for future colliders. • At Barcelona we have created a the full chain for sensor production, assembly and testing available. Future Work • Continue with the collaborations established. • Start fabrication of detectors in 6” wafers. • Slim edges (or active) and charge multiplication effect. G. Pellegrini 27