Detector module development for the CBM Silicon Tracking System

Anton Lymanetsfor the CBM collaboration

Universität Tübingen, Kiev Institute for Nuclear Research

KINR

2

STS terminology

05.03.2013

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013

station 1

station 2

station 4

station 6

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 3

Module concept05.03.2013

sensor1024 strips58 μm pitch

microcablemultilayer

Module design is driven by the material budget and noise requirements.

front-end board8 chips with 128 channels each

To be mounted support structurescarbon fibre

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A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 4

Sensor + cable

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• 1024 strips• ± 7.5 stereo angle• 58 μm strip pitch• (6262) mm2 size

Multi-layer cable mock-up

Cable structure

Wide cable is to be connected to a sensor

Kapton mesh

Kapton

Al

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 5

Sensor + cable interconnection

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Daisy-chained sensors

Sensor-to-cable connection

Mechanical and handling studyExperience: alignment of a cable with 1024 strips is difficult!

Connection technology: TAB bonding

L-shaped legs for sensor mounting

Manufactured in Kharkiv(SE SRTIIE)Talk: M. Singla HK 35.7

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 6

Sensor + cable prototypes

05.03.2013

See: T. Balog HK 35.8 Performance evaluation of a module prototype

Compatible with current n-XYTER front-end boards with ERNI connectors

30 cm

Goal: demonstrate the cable concept, TAB bonding, long cables

•2128 channels(double-sided

readout)•Different lengths

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 7

New module assembly concept

• Many narrow cables (128 channels each)• Same multi-layer structure• Mitigate alignment, yield and testability risks

05.03.2013

8

Sensor quality assurance

•Visual inspection•Electrical characterization▫Current-voltage▫Capacitance-voltage behavior▫Interstrip parameters: resistance and capacitance▫Channel yield (coupling capacitors, PN-junctions)▫Double-metallization▫Shorts and breaks

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A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013

1300+ double-sided sensors have to be tested: probe station, long term stability, etc…

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 9

Front-end electronics

05.03.2013

FEE prototype base on n-XYTER chip STS front-end board concept• STS-XYTER chip• 8 chips (128 channels each)• Chips are wire-bonded to the PCB

Readout chips have to be tested individually before FEB assembly.

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 10

Module assembly steps

05.03.2013

Tested chip + tested cable

Readout test only after full assembly every component has to be testedNeed quality assurance, logistics and tooling for module production

TAB bond both sensorsides using fixtures(non-reworkable)

Nest chips in a FEB,Wire bond to the PCB

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 11

Low-mass support structures

05.03.2013

Mechanical study: carbon fibre support

• ultra-light: mass 14 g/m• mechanical precision within 100 μm• maximal rigidity

A. Lymanets - Detector module development for the CBM STS - DPG Dresden 2013 12

Summary

•Module hierarchy developed•Quality assurance tasks▫Sensors▫Cables▫Front-end-electronics▫Tooling and procedures are under development

•Fixtures for quality assurance and module assembly

•Quality assurance for >1000 modules will be required

•QA sites in Germany (GSI, Tuebingen) and Russia (Dubna)

05.03.2013