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Rui De Oliveira

Vienna March 2014

Industrialisation of Micromegas detector for ATLAS Muon spectrometer upgrade

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• Principle of the detector

• Structure of the detector : BULK or STD

• Production techniques

• Technology transfer to industry status

• Other similar projects

• Prices

OUTLINE

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Principle

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Resistive Bulk Micromegas real cross section

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Read-out board with Cu strips and resistive strips

Laminated Photoimageable coverlay

Frame

SS Stretched meshon metal frame

Laminated Photoimageable coverlay

Exposure Development+ cure

BULK Micromegas production steps

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BULK Micromegas examples

Largest size produced:1.5m x 0.6mLimited by equipment

BULK TechnologyDUPONT PC 1025 coverlayBOPP Meshes

T2K ILC DHCAL

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Read-out board with CU strips and Res strips

Laminated Photoimageable coverlay

SS Mesh on metallic frame

Exposure Development+ cure

STD Micromegas detector production steps

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STD Micromegas structure

Mechanical support

Mechanical support

Drift electrode

Pillars (128 µm)

Open

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Closed

Mechanical support

Mechanical support

STD Micromegas structure

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• Limited dead zones at the edge ( good for TPC application)• The PCB is the detector , it can be tested at the production site• Perfect for low mass detector• Self supporting• 100% compatible with mass production tools available in industry• Cylindrical detectors

BULK advantages:

BULK disadvantages:• Production in a clean room is mandatory to avoid dust trapping • Needs temporary frames during production• Limited to 0.6m width in industry (1m at CERN)

STD advantages:• Extra Large possible sizes (2.4m x 1m)• Can be re-opened and re-cleaned• Low cost for large detectors• 100% compatible with mass production tools available in industry

STD disadvantages:• Needs stiff and flat panels to handle read-out board and drift board• Planarity below 150um is mandatory (but was easily reached in all prototypes)• Paradoxically difficult to build in small size

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Semi automatic machinePrinting area 1.5m x 0.9m

Screen printed resistive layer :

50um Kapton + resistive strips50um Kapton

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Stretching and gluing of the mesh

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ATLAS NSW project

• Quantity• 1728 modules including 192 spares• Around 1200 m2

• Size • 1/3 2.3m x 0.5m• 2/3 2m x 0.5m

• Timescale • 1year

• Targeted Companies for mass production • PCB producer• Screen print frame producer• Screen printing company (technical or graphic art)

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ATLAS NSW project construction step by step

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PCB + readout strips

50um Kapton + resistive strips

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PCB + readout strips

50um Kapton + resistive strips

25um solid Glue

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PCB + readout strips

50um Kapton + resistive strips

25um solid Glue

High temp Gluing

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PCB + readout strips

50um Kapton + resistive strips

25um solid Glue

High temp Gluing

Pillars creation

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PCB + readout strips

50um Kapton + resistive strips

25um solid Glue

High temp Gluing

Pillars creation

mesh

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• 2m x 1m detector • Read-out board with pillars in 4 parts• 10 mm thick honeycomb panel on both sides

ATLAS R&D real detector

Drift panel Read-out panel

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Industry status

• 3 PCB companies have been chosen for technology transfer (France/Italy/US)

• The technology transfer have started 2 years ago• 3 coordinators are following the 3 companies• Companies' technician trainings have been organized at CERN• For sizes up to 50cm x 50cm they are now able to provide all the parts nearly as STD parts• Large single side read-out boards and drift board up to 2.2 x 0.5m OK• Screen printing of resistive layer up to 2.2m x 0.5m OK• Pillars on large area OK• Large size gluing (2.5m x 0.5m) in progress

• Vacuum press • Autoclave

• Mesh on frame (100% std)• Swiss producer• Stretching 2m x 1m mesh OK• Max possible size: 3.4m x 2.2m

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Test already performed

• Accuracy of copper strips on the PCB• Better than 50um over 2 meters for the 3 suppliers

• Accuracy of drilling and milling• Better than 30um

• Resistive layer to metallic layer max misalignment • No influence up to 2 degrees misalignment

• Materials:• STD FR4 High TG or equivalent (many suppliers up to 2.2m x 0.6m but only one for 2.4m x 0.6m)• Kapton H foils or equivalentOK• Screen printed resistors or DLC vacuum deposition OK• Photoimageable coverlay from Dupont ( we are looking for a second supplier)but OK• Stainless steel mesh OK

• Long term stability• Strong Irradiation test to verify the full life of the detector OK

• Beam test • All the classical test have been performed during short beam test sessions • Some small detector are already running in ATLAS since few years• A set of larger detectors (1m x 0.5m) will be installed soon in ATLAS for real conditions tests

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Other possible project with similar technology

• Geoscience• Muon tomography

• Homeland security• Muon tomography

• Calorimeters • LHC upgrades• ILC

• Muon spectrometers for HEP• LHC upgrades

• TPC• LHC upgrade• ILC

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Price for 50cm x 50cm detector!

• List of all the parts or processes needed to create one detector• 2 Stiffening honey comb panels • 1 Read-out board (1D read-out) • 1 Drift board• 1 Kapton foil with resistive strips• Gluing the resistive layer • Pillars made by photolithography• 1 Stainless steel Mesh • Mesh gluing• 1 Drift spacer frame• Screws /o-ring /gas inlet /HV plug• Assembly

• For 1 detector 50cm x 50cm the price is in the range of 5000 CHF

• For 1000 x 50cm x 50cm detectors we are today below 250 CHF /detector

• These prices are based on offers received from European companies

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Thank youQuestions?