XH Germanium Microstrip Detector for EDAS.

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1 XH Germanium Microstrip Detector for EDAS. Janet Groves /Jon Headspith STFC Daresbury Laboratory STFC Technology

2 Slide title Outline Brief History of EDXAS detectors at STFC Photodiode array (PDA) Prototype Si microstrip XCHIP XSTRIP XH Technical details Experimental results Developements 2

3 PDA 512/1024 strips Hamamatsu and Reticon devices 1ms frame rates Efficiency poor Radiation damage

Slide title Prototype Si microstrip Building on the Si microstrip technology and the MX4 readout ASICs implemented in particle phyisics detectors Prove that a system could be developed.

4 Slide title Prototype Si microstrip Building on the Si microstrip technology and the MX4 readout ASICs implemented in particle phyisics detectors Prove that a system could be developed. Comparison of stepped and silicon microstrip EDE data for 5 micron nickel foil Absorbtion (arb units) Io raw Io Kapton Stepped data Ene r gy (e V) 4

High frame rates and high linearity for the XH and XSTRIP detectors are accomplished by using custom designed ASIC frontend the XCHIP Slide title XCHIP/X2CHIP The XCHIP is: 128-channel integration

5 High frame rates and high linearity for the XH and XSTRIP detectors are accomplished by using custom designed ASIC frontend the XCHIP Slide title XCHIP/X2CHIP The XCHIP is: 128-channel integration amplifier array with data storage and multiplexed outputs Data storage allows simultaneous readout and integration Multiplexing allows reduction of 128 channels to 4 (or 1) output node Integration time ~1μs to ~1s Feedback capacitor 2pF or 10pF Maximum charge 15pC positive, 10pC negative (for 10pF feedback) Gain -500mV/pC (2pF) or -100 mv/pc (10pF) Noise at output <50 mv rms Non-linearity <0.1% over +10pC dynamic range Output settling 200ns (to within 0.1mV of final value) 5

6 Slide title XCHIP linearity For EDXAS the linearity is everything 6

7 XSTRIP 500μm thick Si detector1024 strips, 25μm pitch 8 XCHIPs providing the parallel readout 32 channel DAQ system XSTRIP on ID24

8 XH Worlds first 1024 strip 50um pitch Ge detector Designed to address-: Detection Efficiency. Radiation Damage. XH on ID24

9 Ge Sensor Outer guard ring Inner guard ring Al a Ge Ge (p) Bias Al B implant

10 XH detector head Cold plate Thermally isolated readout circuit (230k) 32 channel DAC (offset control) LVDS control signal inputs Ceramic thermal break Ge sensor (105k) X2CHIP readout ASICs (x8) 32 Buffer amplifiers Thermal control via PT100 Power Resistors

12 XH DAQ PC Based What we have now: PC running XP, hosting 32 ADC channels, 14 bit 10MHz (running at 4.16MHz) 2 large Xilinx FPGA carrying out data accumulation 2 DSP processors acting as host interface processors DAQ specific Readout in 10us Frame storage 20us 1700 frames

13 Radiation tolerance: Dark current baseline High leakage strips V_dark1_10us V_dark1_1000us Faulty readout circuit Data taken prior to start of experimental beamtime on ESRF ID24 Average dark current ~ 26.6pA STFC Technology

14 Radiation tolerance: 1 week of beamtime High leakage strips Dark13_10_50.02V Dark13_1000_50.01V Faulty readout circuit Data taken at completion of experimental beamtime on ESRF ID24 Average dark current ~ 29.9pA STFC Technology

15 System Linearity Intensity (arb) dynamic range (scaled to 1) strip number Io-Iod(220us) It-Itd(220us) Io-Iod(200us) Io-Iod(180us) Io-Iod(160us) Io-Iod(140us) Io-Iod(120us) Io-Iod(100us) Io-Iod(80us) Io-Iod(60us) Io-Iod(40us) Io-Iod(20us) Io-Iod(10us) Io-Iod(5us) Io-Iod(1us) Sum(350:850) Io, It data at various integration times %error Linearity Io/It varying Io Io/It 1.0E E E E E E+000 Io/It: It fixed, Io varying Strip number Linearity data taken from measurement of ESRF- ID24 undulator profile integration time (us) % INL STFC Technology

16 Spatial resolution raw counts Increasing bias improves LSF Slit width vs bias voltage strip number At a bias of => 50V spatial resolution ~ 3 strips FWHM LSF At a bias of 50V minimised dark current noise Increasing bias increase the dark current contribution 50V 55V 60V 65V 20V 25V 30V 35V 40V 45V 70V 75V STFC Technology

17 Slide title Spatial resolution - Rh foil Rh Foil comparison Ln Io/It BM29 Stepped scan SRS9.3 ESRFID E (kev) -1 17

18 Rh foil, accumulated readouts at low and high rates More Spatial resolution -Rh foil 2.3 Scan=1, lowrate Scan=1, highrate Scan=10, lowrate Scan=10, highrate 1.8 Scan=100, lowrate Scan=100, highrate Scan=1000, lowrate Ln ((Io-Iod)/(It-Itd)) Scan=1000, highrate Low rate : I0=13μs, It 35μs High rate : I0=0.6μs, It 1.6μs strip number STFC Technology

19 Slide title Single bunch 100 Single bunch Fe foil 6 ~520 ph It-Itd (full dynamic range = 4095) It-Itd Ln((Io-Iod)/(It-Itd)) ~120 ph Ln Io/It strip number 3 ESRF 4 bunch mode, 700ns gaps, capture a single bunch 19

20 Slide title More bunches 4 Fe foil for various numbers of bunches bunch 10 bunches 50 bunches 500 bunches 2.5 Ln(Io/It) + scaling strip number 20

21 Recording bunches around orbit -8.6E+08 sum of detector data vs orbit delay E E E+08 intensity (arb) -9E E E E E+08 delay from orbit Clock (ns) Tint Tinit Tinit100-12

22 Developments Development with DLS I20 New Ge sensor from LBNL New readout system for detector being developed by P Coleman- Smith for the AIDA nuclear physics programme currently awaiting final project approval Support up to 2048 strips via 64 ADC channels FPGA data acquisition system running LINUX with Gbit Ethernet connectivity. Increased sampling rate Support 7.5μs readout and frame storage Support frames Support for integration times <500ns (aiming for 300ns) readout time will remain at 7.5μs incurring dead time

23 Longer term developments New XCHIP is designed for high linearity not high speed - Potentially a new XCHIP design that trades off linearity (and signal to noise) specifically for single bunch experiments 1536 element Ge currently the limit of the wafer diameter 2048 element Si device IO measurement concurrent I0 would greatly improve data quality. This needs to be addressed.

24 LBNL STFC P N Luke, J S Lee, M Annan, W D Goward Acknowledgements in no particular order! G Salvini, M Kogimtzis, S L Thomas, R Farrow, I Harvey, S Fiddy, G Derbyshire, I Lazarus, P Coleman-Smith, Zhi-Jun Xin Southampton University J Evans, M Tromp DLS ESRF A Dent, S Diaz-Moreno, T Rayment O Mathon, C Ponchut, S Pascarelli, Mark Newton

25 Slide title Scan Showing beam movement on Id24 25

26 Slide title End End 26

27 Slide title 27

28 Specification Germanium 1024 strips 50um pitch Silicon 1024 strips 25um pitch 5mm Strip length 1mm Thick 2.5mm Strip length 500um Thick Leakage current <30pA 100v bias Leakage current <10pA 70v bias Energy Range5-40Kev Energy Range5-15Kev

29 Slide title Detection medium Ge Number of strips 1024 Strip pitch 50mm Strip length 5mm Detector thickness 1mm Energy range 5-40keV. 30keV 29

ITk silicon strips detector test beam at DESY

ITk silicon strips detector test beam at DESY Lucrezia Stella Bruni Nikhef Nikhef ATLAS outing 29/05/2015 L. S. Bruni - Nikhef 1 / 11 Qualification task I Participation at the ITk silicon strip test beams