The ATLAS Pixel Detector Looking at about 15 minutes with questions… One slide per minute -> ~15 slides (16 inc. title) But remember, way the way to think about it is to come up with the story first, then work out the visual aids I’ll need, then work the story back around the visual aids… A CERN Summer Student’s-Eye View CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

SLAC, USA White Horse, UK Stone Henge, UK Cerne Abbas Man, UK As you probably know, this is the SLAC accelerator… (Click) This might not be so familiar… carved into the hillside It was an attempt by early British man to You can see where this is going... (Click) Yeah, that’s right. SLAC is basically the physicist’s way of expressing It took you Yanks a little longer, but you got there in the end… CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Where is the Pixel Detector? 1.3m long, 33cm diameter, 1.7m2 active detector area CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Pixel Detector Requirements Spatial resolution: 10mm Temporal resolution: 25ns Radiation hardness: 3 x 1014 cm-2 NE per year CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Silicon Detectors – The Basics Extra holes (III) p-type Silicon Extra electrons (V) n-type Silicon CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Silicon Detectors – The Basics p-type Silicon Induced Electric Field Depletion Zone n-type Silicon CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Silicon Detectors – The Basics p-type Silicon Applied Voltage Depletion Zone Active Detector Area n-type Silicon Reverse biased pn-junction CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Silicon Detectors – The Basics p-type Silicon Depletion Zone Applied Voltage Active Detector Area n-type Silicon CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Silicon Detectors – The Basics To readout p-type Silicon Depletion Zone Applied Voltage Active Detector Area n-type Silicon CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

The Pixel Module 1744 modules  ~ 80 million pixels! 2D array of sensors Module Controller Chip (MCC) Front End (FE) electronics chips: 160 x 18 = 2889 pixels per chip 16 chips per module Circuit board Silicon sensor “Bump bonds” 1744 modules  ~ 80 million pixels! CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

What Does a Pixel Module Need? High Voltage (HV) supply – depletes the silicon  600V Data Opto board supplies  2 V Temperature sensor resistor (NTC) readings For Interlock Low Voltage (LV) supplies – powers the FE electronics  2.5 V CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

My Project – The Problem Pixel modules are expensive Supply kit can be badly designed / made Need a “module substitute” Number of supply lines: ~7500 $ Test Box CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

My Project – The Solution CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

The Implementation ISEG High Voltage (HV) PP2 Low Voltage Wiener (LV) Power Supply LV PP4 LV High Voltage (HV) ISEG HV PP4 HV PP2 Regulator Board NTC / Optoboard SCOLink NTC Opto PP3 OPTO BBM BBIM HV Power (VDET) LV Power Opto Power VISET, VPIN, OPTO_RST NTC, NTC_OPTO Sense lines VVDC VDD, VDDA NTC lines Interlock Type IV Type III Type II Cabling: CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

The Implementation DCS HV Test Box PC Keithley 7708 40 Channels 26 x VDET 2 x SAFE 2 x DRAIN DCS HV Test Box HV 26 x VDET PC AWG26 (from LEMO cable) GPIB 26 x VDET 2 x SAFE 2 x DRAIN 13 x VDET HV Test Box Keithley 7708 40 Channels HV 13 x VDET AWG26 (from LEMO cable) Keithley 2700 Scanning DMM Max 300V 26 x VDET 2 x SAFE 2 x DRAIN 26 x VDET HV Test Box HV Keithley 7708 40 Channels AWG26 (from LEMO cable) CERN Summer School 15th August 2006 AWG22 (for7708 screw terminals) Tom Whyntie University of Cambridge

The Implementation Challenges: Physical Simulation Automation 7001’s, Agilent and Scanning DVM connect to PC (via GPIB), which then connects to the DCS… 2 x Keithley 7166 2 x 1 x 10 Channels Keithley 7001 Switching Matrix Agilent N3300A Active Load Mainframe Challenges: Physical Connections Test Conditions Simulation Automation 7 x VDD 7 x VDDA 1 x VVDC AWG26 (LEMO cable) LV Resistors (Type 0 and 1 cables) 5 x Agilent N3302A: Load Modules 7 x SENSE_VDD 7 xSENSE_ VDDA 1 x SENSE_VVDC 13 x NTC 2 x NTC_OPTO AWG22 (recommended) 13 x NTC 2 x NTC_OPTO 6 x Opto Voltages Keithley 7011S 4 x 1 x 10 Channels NTC/Opto Test Box Keithley 7001 Switching Matrix 2 x VISET 2 x VPIN 2 x OPTO_RST NTC/ Opto Scanning DMM AWG26 (LEMO cable) CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Actual Use of the Test System CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Conclusions Outcomes for CERN: Outcomes for me: Pixel Services Test System designed Will be implemented in near future;  At least the Pixel Detector will work Outcomes for me: Not massively physics-based… But learnt a lot about everything else. Appreciation of the scale of CERN Engineering effort, collaborations, etc. CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge

Thanks for listening! Acknowledgements: CERN The Summer Student team – thanks for a great programme! ATLAS Pixel Detector Group Kevin Einsweiler (LBNL), Project Leader Sidney Sussex College, University of Cambridge And last, but not least… Markus Keil (CFTP Lisbon), Summer Project Supervisor So, how do you get around this problem? CERN Summer School 15th August 2006 Tom Whyntie University of Cambridge