S ummary of measurements after first irradiation of HPK samples

1. Summary of measurements after first irradiation of HPK samples for CMS Summary of measurements after first irradiation of HPK samples 19th RD50 Workshop 21-23 November 2011 CERN Joachim Erfle University of Hamburg On behalf of the CMS Tracker Collaboration

2. Summary of measurements after first irradiation of HPK samples for CMS Overview • introduction to the HPK-campaign • results of first irradiations • dark current • effective doping concentration • signal collection • conclusions courtesyof A. Dierlamm, KIT

3. Summary of measurements after first irradiation of HPK samples for CMS Goals ofthe HKP-campaign • The mainchallengesofthe HL-LHC will be: • higherradiationdamage • higheroccupancy • thereforewewantto find thebestsuitingmaterial andlayoutforthecomingtrackingsensors. • Toachievethatweinvestigate a large varietyofmaterialsandstructuresthatareirradiatedandmeasured. • The firststepisto check, ifatlowfluenceseverythingiscompatiblewithavailabledata. After thatwe will gotohigherfluences.

4. Summary of measurements after first irradiation of HPK samples for CMS Wafer overview

5. Summary of measurements after first irradiation of HPK samples for CMS Material • ofeach material thereare 3 different types: • n-type (N) • p-type with p-stop (P) • p-type with p-spray (Y)

6. Summary of measurements after first irradiation of HPK samples for CMS Material characteristics of thin FZ: deep diffusion Concentration profile from CV-curve: 320-N µm 120-N µm 120-P µm J. Erfle, UHH Diodes behavelike parallel-platecapacitors → measurecapacitancevsvoltagetodeterminedepletiondepthandchargecarrierconcentration J. Erfle, UHH front Deep diffusion influences effective doping

7. Summary of measurements after first irradiation of HPK samples for CMS Irradations HL-LHC: Lint=3000 fb-1 • neutrons: 1 MeV (TRIGA Reactor Ljubljana) • protons: 25 MeV (Karlsruhe Synchrotron) courtesyofS. Müller, KIT

8. Summary of measurements after first irradiation of HPK samples for CMS Volume current versus fluence: protons neutrons neutrons protons currentsaremeasured after annealingof 10 min@ 60°C at 0°C andscaledto 20°C J. Erfle, UHH currentsmatchexpectedvaluefromM.Moll‘sthesiswithintheuncerntainties. -> dose measurementsare ok.

9. Summary of measurements after first irradiation of HPK samples for CMS Volume current versus fluence:Baby sensors neutronirradiated Baby sensors First Baby sensorsshowhighercurrentsthandiodes -> maybe a surfaceeffect? currentsaremeasured after annealingof 10 min@ 60°C at -20°C andscaledto 20°C courtesyofA. Nürnberg, KIT

10. Summary of measurements after first irradiation of HPK samples for CMS Annealingbehaviourofdarkcurrent p@3E14 resultsforneutronirradiationcomingsoon 80°C J. Erfle, UHH measurementsareperformedat 0°C andscaledto 20°C theannealingofalphamatchestheexpectedcurvefromM.Moll‘sthesis.

11. Summary of measurements after first irradiation of HPK samples for CMS Nefffor different materials / irradiations n-type protons the FZ andtheMCz n-type materialsare type-inverted after neutronorprotonirradiation. J. Erfle, UHH neutrons capacitancesaremeasuredat 0°C, 1KHz after annealingof 10min@60°C J. Erfle, UHH

12. Summary of measurements after first irradiation of HPK samples for CMS Nefffor different materials / irradiations n-type p-type protons J. Erfle, UHH J. Erfle, UHH neutrons J. Erfle, UHH capacitancesaremeasuredat 0°C, 1KHz after annealingof 10min@60°C J. Erfle, UHH MCz: lowestincrease in Neff.

13. Summary of measurements after first irradiation of HPK samples for CMS Time resolvedchargecollectionmeasurementwith Transient CurrentTechnique (TCT)TCT curvesshow type inversion FZ320N - holes - electrons FZ320P courtesyof J. Lange unirradiated p@3E14 Laser: 672 nm, red courtesyof T. Pöhlsen, UHH courtesyof T. Pöhlsen, UHH not type inverted U=600V type inverted U=300V type inversionof FZ andMCz n-type materialsisconfirmedby TCT. capacitancesaremeasuredat 0°C, 1KHz after annealingof 10min@60°C

14. Summary of measurements after first irradiation of HPK samples for CMS Annealingbeaviourof Neff p@3E14 FZ320P unirradiated unirradiated FZ320N 80°C J. Erfle, UHH Neffchangesof FZ320N typicalfor type inverted material. FZ320P behaviourlookssimilar but is not type inverted: not completelyunderstoodyet. measurementsareperformedat 0°C (1KHz)

15. Summary of measurements after first irradiation of HPK samples for CMS Signal of FZ320P babysensor, after p@3E14 signalinducedby a 90Sr source, readoutbyALiBaVa Vdepl CCE of FZ320 p-type isabout 87% at p@3E14, comparedto non-irradiated measurementsareperformedat -20°C courtesyof K. Hoffman, KIT

16. Summary of measurements after first irradiation of HPK samples for CMS CCE ofdiodes, after p@3E14 redlaser, front injection infraredlaser courtesyof J. Lange unirradiated n-type p-type n-type: electron collection p-type: hole collection courtesyof T. Pöhlsen, UHH courtesyof T. Pöhlsen, UHH measurementsareperformedat 0°C and 600V, with 20ns integration time infraredlaser: CCE isabout 90% electronsonly: CCE ~ 85%, holescollectiononly: CCE ~ 67%

17. Summary of measurements after first irradiation of HPK samples for CMS Conclusions and outlook • CMS silicon measurement campaign is gaining speed, analysis tools are up and running • Trying to understand material properties in detail • Comparison shows currents as expected -> dose measurement ok • Neff compared before and after irradiation • CCE with baby sensors and diodes investigated • More irradiations to come • Full annealing studies to be done

18. Summary of measurements after first irradiation of HPK samples for CMS Backup

19. Summary of measurements after first irradiation of HPK samples for CMS CCE of FZ320 after protonirradiation courtesyof T. Pöhlsen measurementsareperformedat 0°C

20. Summary of measurements after first irradiation of HPK samples for CMS TCT pulses – p-type FZ200P FZ320P MCZ200P courtesyof T. Pöhlsen courtesyof T. Pöhlsen courtesyof T. Pöhlsen 300V 600V 250V measurementsareperformedat 0°C, using a redlaser not type inverted

21. Summary of measurements after first irradiation of HPK samples for CMS TCT pulses – n-type FZ200N FZ320N MCZ200N courtesyof T. Pöhlsen courtesyof T. Pöhlsen courtesyof T. Pöhlsen 300V 300V 200V type inverted measurementsareperformedat 0°C, using a redlaser

22. Summary of measurements after first irradiation of HPK samples for CMS Interstrip capacitance on teststructureafter neutronandprotonirradiation low high low Bias TS_CAP_AC courtesyof M. Bernard-Schwarzz, HEPHY courtesyof M. Bernard-Schwarzz, HEPHY measurementsareperformedat -20°C, 1MHz Interstrip capacitance also isstable

23. Summary of measurements after first irradiation of HPK samples for CMS Interstrip resistance on teststructure V unirradiated Bias GOhm TS_CAP_DC courtesyof M. Bernard-Schwarzz, HEPHY courtesyof M. Bernard-Schwarzz, HEPHY interstripresistance in unirradiated material isprettygood. measurementsareperformedat -20°C

24. Summary of measurements after first irradiation of HPK samples for CMS Strip structures: measurementofbasicproperties courtesyof M. Bernard-Schwarz, HEPHY Basic propertiesdon‘tchangeatthesefluences measurementsareperformedat -20°C, (1kHz)

25. Summary of measurements after first irradiation of HPK samples for CMS Interstrip resistance on TS protonirradiated unirradiated MOhm courtesyof M. Bernard-Schwarzz, HEPHY GOhm courtesyof M. Bernard-Schwarzz, HEPHY neutronirradiated MOhm courtesyof M. Bernard-Schwarzz, HEPHY interstripresistanceon teststructuresdropsfrom >200GOhm to <200MOhm after irradiation resistances on babysensors in similarrange measurementsareperformedat -20°C

26. Summary of measurements after first irradiation of HPK samples for CMS oxygencontent

27. Summary of measurements after first irradiation of HPK samples for CMS fluencecomputedfromdatawith a fixedalpha neutrons, 4E14 protons, 2.9E14 protons, 1.1E14 neutrons, 1E14 currentsaremeasuredat 0°C andscaledto 20°C

28. Summary of measurements after first irradiation of HPK samples for CMS interstripresistance on babysensor protonirradiated protonirradiated FZ320P courtesyof M. Bernard-Schwarz FZ320N neutronirradiated courtesyof K. Hoffmann interstripresistancedrops on babysensorsfrom >100GOhm to >100MOhm courtesyof M. Bernard-Schwarz measurementsareperformedat -20°C