1. 6 July 2010 Thomas Bergauer (HEPHY Vienna) Status of Double Sided Silicon Sensors B2GM

2. DSSD news Overview Introduction Micron Status HPK Status Beam test and Irradiation 2Thomas Bergauer (HEPHY Vienna)6. July 2010

3. DSSD news INTRODUCTION 3Thomas Bergauer (HEPHY Vienna)6. July 2010

4. DSSD news 10 June 2010 Vendors for 6” DSSD Aim is to use double sided silicon detectors with AC-coupled readout and poly-silicon resistor biasing from 6 inch wafer 4T. Bergauer Hamamatsu decided in the past to abandon the production of double sided sensors Thus, negotiations with Canberra, SINTEF and Micron started Finally HPK could be convinced to restart DSSD production on 6” wafers 6” prototypes ordered from –Hamamatsu (rectangular): First batch delivered in April –Micron (trapezoidal): First batch in July

5. DSSD news 5Thomas Bergauer (HEPHY Vienna)19. Nov. 2009 SVD Layout Layer# Ladders Rect. Sensors [50μm] Rect. Sensors [75μm] Wedge Sensors APVs 61706817850 51404214560 41002010300 381600192 Sum:4916130411902

6. DSSD news MICRON STATUS 6Thomas Bergauer (HEPHY Vienna)6. July 2010

7. DSSD news Trapezoidal Sensors (Micron) Full wafer designed using self-developed framework Including test structures and mini sensors to test different p-stop designs Delivery due July 2010 Trapezoidal sensor with test structures Sensor “programming language” 7Thomas Bergauer (HEPHY Vienna)5 July 2010

8. DSSD news Trapezoidal sensor – p-side 768 readout strips 75-50 µm pitch (fan shaped) 767 intermediate strips (not read out) Multi-guard-ring structure –10 guard rings to control voltage drop 8Thomas Bergauer (HEPHY Vienna)5 July 2010

9. DSSD news Trapezoidal sensor – n-side 512 readout strips 240 µm pitch 511 intermediate strips (not read out) Similar multi-guard-ring structure Strips and rings separated by p-stop implants 9Thomas Bergauer (HEPHY Vienna)5 July 2010

10. DSSD news Micron Wafer Layout Teststructures for p-side Teststructures for n-side (no GCD) Baby sensor 1 p-side: 512 strips 50 µm pitch 1 interm. strip n-side: 512 strips 100 µm pitch 1 interm. strip atoll p-stop 3 different GCDs for the n-side Main sensor p-side: 768 strips 75-50 µm pitch 1 interm. strip n-side: 512 strips 240 µm pitch 1 interm. strip combined p-stop Quadratic baby sensors 2,3,4 p-side: 512 strips 50 µm pitch 1 interm. strip n-side: 256 strips 100 µm pitch 0 interm. strip different p-stop patterns 1) atoll p-stop varying distance from strip 2) conventional p-stop varying width 3) combined p-stop varying distance from strip 1) 2) 3) 10Thomas Bergauer (HEPHY Vienna)5 July 2010

11. DSSD news 11Thomas Bergauer (HEPHY Vienna)5 July 2010 News from Micron Processing of first sensor is finished –is supposed to be tested this week –Last update (29. June): they are currently writing a test software If OK, final processing of six more sensors this month Shipping of the first batch end of this month or early next month

12. DSSD news HPK STATUS 12Thomas Bergauer (HEPHY Vienna)6. July 2010

13. DSSD news First batch from HPK First 20 pieces of 6’’ sensors have been delivered in April 2010 Technical details: Dimensions: 59.6 x 124.88 mm p-side: Readout pitch: 75 µm 768 strips n-side: Readout pitch: 240 µm 512 readout strips n-side P-stop scheme 10 June 201013T. Bergauer

14. DSSD news HPK Polysilicon Resistors Specifications of Polysilicon Resistors 18 March 2010 by HPK Process parameters Poly resistor Measurment results (Mega Ohm) Serial No.PsideNside MAXMINAVE 1P1N1P117.615.116.3 2P1N1P246.335.641.1 3P1N1P37.16.46.8 4P1N2 5P1N2N120.515.317.4 6P1N2 7.26.26.5 7P1N2N33.32.72.9 8P1N3 9P1N3 10P1N3 11P1N3 12P2N2 13P2N2 14P2N2 15P2N2 16P1N2 17P1N2 18P1N2 19P3N2 14T. Bergauer10 June 2010

15. DSSD news Characterization HPK Sensors 15T. Bergauer10 June 2010 Electrical Characterization done in Vienna and KEK –IV, CV –Stripscan (p- and n-side) –Longterm stability vs. temperature and humidity –Inter-strip resistance Pull-tests to show bondability

16. DSSD news 16 How to bias the DSSD for testing? 2 strategies: –contacting bias on both p- and n-side (uncomfortable) –contacting bias and n-sub on p-side (easy, bulk tests and strip tests of p-side) Measurement shows hardly any difference -> we save a lot of trouble!

17. DSSD news IV Measurements Consistent between Vienna and HPK measurement (except #2) 17Manfred Valentan (HEPHY Vienna)16 June 2010 HPK data Vienna data

18. DSSD news CV Measurements Shows full depletion voltage between 50 and 60V 18Manfred Valentan (HEPHY Vienna)16 June 2010 Vienna data KEK data

19. DSSD news Long-term IV measurement Apply bias voltage (100 volts) for 1 week Measure currents continuously while varying r.H. => sensors stable with time 19Thomas Bergauer (HEPHY Vienna)6. July 2010 I [uA] Time [10 min]

20. DSSD news Stripscan (Sensor #4) n-side p-side 20Thomas Bergauer (HEPHY Vienna)6. July 2010

21. DSSD news Strip failures in the HPK data HPK inspects all strips in the DSSD. HPK categorizes strip failures as below: - Coupling short - AC AL short - AC AL open - Implant short - Implant open Almost all of failures are implant short and open in P-side. No or only few coupling shorts, AC AL shorts and AC AL opens exist. Onuki-san Id(0V)4.776 Coupling short Id(40V)3343 AC AL short Id(80V)4157PAC AL open 8Id(120V)4224 Implant short5678910117172271317437530541581582583620 Id(160V)4276 668688689 Id(200V)4330 Implant open5196113114237366460461638 Temp. 26 ℃ Coupling short NAC AL short275276 Vfd[V]60 AC AL open

22. DSSD news Correlation HPK Vienna Data (p-side) 22Thomas Bergauer (HEPHY Vienna)6. July 2010 Onuki-san

23. DSSD news Correlation HPK Vienna Data (n-side) 23Thomas Bergauer (HEPHY Vienna)6. July 2010 Onuki-san

24. DSSD news HPK Data for some Sensors Id(0V)4.769 Coupling short Id(40V)3352 AC AL short Id(80V)4309PAC AL open 4Id(120V)4392 Implant short3972117165168212275377378541587633634635677678716727 Id(160V)8097 Implant open8485123247272351352380548672693 Id(200V)24280 Coupling short Temp. 26 ℃ NAC AL short242243253254277278301302 Vfd[V]65 AC AL open 24Thomas Bergauer (HEPHY Vienna)6. July 2010 Id(0V)4.776 Coupling short Id(40V)3343 AC AL short Id(80V)4157PAC AL open 8Id(120V)4224 Implant short5678910117172271317437530541581582583620 Id(160V)4276 668688689 Id(200V)4330 Implant open5196113114237366460461638 Temp. 26 ℃ Coupling short NAC AL short275276 Vfd[V]60 AC AL open

25. DSSD news Measurement of the interstrip resistance A -100V GND Electrometer SMU 1 GND 0...3V (5V) GND A SMU 2 applies bias voltage ramps potential on neighbouring DC pad -> Bias resistor value from slope of current Current at 0V is strip leakage current, interstrip resistor value from slope of current when ramping Method seen in Karlsruhe 25Thomas Bergauer (HEPHY Vienna)6. July 2010

26. DSSD news Measurement of the interstrip resistance I_strip = -5.14 nA R_int = 92.6 GΩ R_poly = 2.8 MΩ HPK sensor 8, n-side, strip 1-2HPK sensor 8, p-side, strip 6-7 I_strip = 1.498 nA R_int = 158.4 GΩ R_poly = 17.9 MΩ PRELIMINARY! These results are from first tests of the method! First stripscan using this method currently ongoing 26Thomas Bergauer (HEPHY Vienna)6. July 2010

27. DSSD news Bonding test Bonding pad metal feels very soft –> we performed a bond test p-side : –Corner: 8.73g, σ = 2.2g (non- optimized bonding parameters) –Center: 11.5g, σ = 0.6g (optimized parameters) n-side : –Corner: 12.2g, σ = 0.6g (optimized parameters) –Center: 12.1g, σ = 0.7g (optimized parameters) Conclusion: although the metal feels soft when contacting by hand, the bond wires hold tight 27Thomas Bergauer (HEPHY Vienna)6. July 201027

28. DSSD news Soft metal issue 28Thomas Bergauer (HEPHY Vienna)6. July 2010 n-side p-side CMS SSSD for comparison

29. DSSD news 29 Scratches & Marks: p-side Triangular stains –visible by eye –visible under the microscope –occurs on every sensor 29Thomas Bergauer (HEPHY Vienna)6. July 2010

30. DSSD news 30 Scratches & Marks: n-side Round scratches –occur on every sensor –maybe due to automatic sensor handling? 30Thomas Bergauer (HEPHY Vienna)6. July 2010

31. DSSD news Residues and other optical issues 31Thomas Bergauer (HEPHY Vienna)6. July 2010

32. DSSD news BEAM TEST AND GAMMA IRRADIATION Last point: 32Thomas Bergauer (HEPHY Vienna)6. July 2010

33. DSSD news Thomas Bergauer (HEPHY Vienna)22 March 201033

34. DSSD news Gamma Irradiation I was in contact with a person of SCK-CEN in Mol, Belgium They have a very strong gamma source (Co-60) with 30kGy/h 20 Mrad will be accumulated in 8h Costs are 2195 Euro (=242k¥) 34Thomas Bergauer (HEPHY Vienna)10 March 2010

35. DSSD news What to test? DSSDs from both HPK and Micron –While powered with HV and read out with origami (=test of APVs, hybrid,…) Micron p-stop test structures 35Markus Friedl (HEPHY Vienna)20 October 2009 1) 2) 3) Other stuff? –Space available: Cylinder with approx 40cm diameter and 60 cm height

36. DSSD news 36Thomas Bergauer (HEPHY Vienna)10 March 2010 Schedule Test beam at SPS (CERN): –27. September until 11. October 2010 Idea is to have gamma irradiation in between, which means: –Test Origami ladder and trapezoidal module at CERN (S/N,…) 4 days –Irradiate (3 days with travel) –Re-Test modules at CERN (2 days) Fits perfectly within two weeks in autumn

37. DSSD news Summary Still waiting for delivery of 1 st batch of trapezoidal sensors from Micron HPK delivered first batch in April –IV behavior reasonable –CV measurements: full depletion voltage ~60V –We are not fully sensitive to their list of single strip failures –Some scratches, residues and soft metal This is the first try for HPK to produce DSSD on 6” –In summary, sensors are of reasonable quality –HPK is not satisfied itself and delayed delivery of second batch We are eagerly waiting to see their improvements Beam test at CERN and Irradiation in Belgium in September/October 2010 under preparation 37Thomas Bergauer (HEPHY Vienna)6. July 2010

38. DSSD news Stripscan Sensor #8 (n-side) I_strip = -3.31 nA R_poly =2.76 Mohm C_ac=186.83 pF No pinhole HPK: AC AL short at strips 275/276 - could be verified by C_ac measurement! 38Thomas Bergauer (HEPHY Vienna)6. July 2010