1. A Large Surface Photomultiplier based on SiPM Carlos Maximiliano Mollo, INFN Naples, Italy Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany

2. Vacuum Photo-Multiplier Tube vs. Silicon Photo-Multiplier VPMT SiPM Single photon counting capable linearity-to-gain ralationshiprobustness Low operating voltages spread in transit time difficulty in single photon counting Hamamatsu R7600 Active area 18 x 18 mm 2 gain >10 6 Dark counts few kcps B-field immunity no Hamamatsu S10931-025P Active area 3 x 3 mm 2 gain2.75 x 10 5 Dark counts few Mcps B-field immunityyes Small sensitive surface!

3. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany To increase sensitive surface Light concentrators Compound Parabolic Concentrators (CPC) Pyramidal concentrators

4. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Compound Parabolic Concentrators (CPC)

5. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Compound Parabolic Concentrators (CPC) Monte Carlo Simulations A detailed simulation of a CPC with 25°acceptance angle (CPC 25° ) has been performed. The simulated CPC 25° is an optical B270 glass cone with 9.01 mm entrance diameter, 2.50 mm exit diameter and 19.25 mm length, which is commercially available by Edmund Optics.

6. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Pyramidal Concentrator Monte Carlo Simulations The pyramidal light concentrator simulated in this work is an optical glass N-BK7 device with 7.5 x 7.5 mm2 entrance surface, 2.5 x 2.5 mm2 exit surface and 50 mm length, commercially available by Edmund Optics. From simulation, a good (and almost uniform up to 20°) transmission efficiency is obtained for this geometry.

7. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Surface sensitivity measurements Pyramidal concentrators Presents an uniform transmission Efficiency over their entrance Surface! CPC Pyramidal Concentrator Steps by 0.100 mm Laser spot diameter: 0.9 mm

8. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany MPPC + Light Concentrator measurements

9. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany For single photon counting applications pyramidal concentrators are better than CPCs Uniform efficiency over entrance surface Better fill factor using matrices of several MPPC + light concentrator Greater acceptance angles than CPC without compromise surface efficiency uniformity Light Concentrator choice

10. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Sensitive surface of Single MPPC + Light concentrator is still too small ( 6 x 6 mm 2 ) MPPCs + Light concentrators matrix Digital OR Circuit based on FPGA

11. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany FPGA (Field Programmable Gate Array) For example a 2x2 Matrix Single MPPC data available Possible control on a MPPC malfunction

12. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany FPGA (Field Programmable Gate Array) Digital circuit developed using Xilinx ISE 10.1 Simulated using ModelSim by Mentor Graphics

13. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany FPGA simulations

14. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany FPGA simulations Processing time: 5 clock cycles Clock @ 200 MHz Processing time: 25 ns

15. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Evaluation Board Analog inputs DATA12 bit LVDS clock DATA 16 bit TTL Ctrl. Add. 4 bit TTL USB connection PC 250 MSps 12 bit LVDS pipelined successive approximation architecture ADC

16. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Evaluation Board Analog inputs DATA12 bit LVDS clock DATA 16 bit TTL Ctrl. Add. 4 bit TTL USB connection PC ADC 12 bits: 4096 levels Reference voltage: 2.5 V Single photo-electron signal: 5 mV 8 quantization levels for each single photo-electron detected Maximum photo-electrons detectable: 500

17. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Timing Analysis ADC Latency L 7.5 Clock Cycles FPGA Latency 5 Clock Cycles Total Latency 13 Clock Cycles 65 ns @ 200 MHz

18. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany FPGA Place and route

19. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Evaluation Board test we have seen a drastic dark counts reduction Using a threshold corresponding to 3 photo-electrons Power consumption: 350 mA @ 5.5V

20. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Our goal To build a 9x9 elements matrix with a total surface of 22.5 x 22.5 mm 2

21. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Modular System We can make a matrix of matrices with the same paradigm used for MPPCs

22. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany Thank you!

23. Dr. Carlos M. Mollo - A Large Surface Photomultiplier based on SiPM - VLVνT Workshop 2011 - Erlangen, Germany References [1] A.A. Radu et al., Nuclear Instruments and Methods in Physics Research A 446 (2000) 497-505. [2] F. Lucarelli et al., Nuclear Instruments and Methods in Physics Research A 589 (2008) 415–424. [3] K. Bernlöhr et al., Astroparticle Physics 20 (2003) 111–128. [4] R. Winston, W.T. Welford, High Collection Nonimaging Optics, Academic Press, New York, 1989. [5] www.edmundoptics.comwww.edmundoptics.com [6] J. Ninkovic et al., Nuclear Instruments and Methods in Physics Research A 617 (2010) 407–410. [7] W.G.Oldham IEEE ‘TRANSACTIONS ON ELECTRON DEVICES, VOL. ED-19, NO. 9, SEPTEMBER 1972. [8] G. Barbarino, R. de Asmundis, G. De Rosa, C. M. Mollo, S. Russo and D. Vivolo (2011). Silicon Photo Multipliers Detectors Operating in Geiger Regime: an Unlimited Device for Future Applications, Photodiodes - World Activities in 2011, Jeong-Woo Park (Ed.) ISBN: 978-953-307-530-3, InTech. [9] KENNET KAD5612P data sheet. [10] XILINX Spartan 3E data sheet.