Performance of the latest prototypes of NUV-HD Silicon Photomultipliers G. Zappalà, F. Acerbi, A. Ferri, A. Gola, G. Paternoster, V. Regazzoni, N. Zorzi, C. Piemonte

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Near-UV FBK SiPM roadmap NUV Cell pitch 40 µm 60 % Fill Factor New Substrate NUV Low-AP (F. Acerbi et. al., NUV Silicon Photomultipliers With High Detection Efficiency and Reduced Delayed Correlated-Noise, IEEE T. Nucl. Sci., Vol. 62, n.3, 2015) NUV-HD New cell border (trenches) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

High-Density technology in NUV NUV-HD SiPM Trench < 2 µm High-field region Poly strip resistor Metal Cell 2 Cell 1 ~ 4.5 µm NUV-SiPM Cell 3 NUV High-Density (HD) technology: Lower dead border region → Higher Fill Factor Trenches between cells → Lower Cross-Talk (C. Piemonte et. al., (2016) IEEE T. Electr. Dev., 10.1109/TED.2016.2516641) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Fill Factor in HD technology Cell Pitch L The HD 15 µm pitch is equivalent to the standard 40 µm 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

NUV-HD SiPM layout features High PDE Cell Pitch 15 µm 20 µm Fill Factor (%) 55 66 #cells/mm2 ~ 4444 2500 25 µm 30 µm 35 µm 40 µm 73 77 81 83 1600 ~ 1111 ~ 816 625 High Dynamic Range 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 PDE Setup SiPM Amplifier board Reference Photod. LED Waveform generator Integrating sphere Pulsed LEDs (UV – NIR) used as light sources Reference Photodiode to monitor the stability of light at SiPM location Amplified signal is acquired by the oscilloscope, synchronised with waveform generator Developed LabVIEW Software used to analyse the signals 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 PDE Analysis Pulses integration Analysis of the charge histogram to know the probability of “No detection” P0 𝑷𝑫𝑬= − 𝒍𝒏 𝑷 𝟎 𝑰𝒎𝒑𝒊𝒏𝒈𝒊𝒏𝒈 𝑷𝒉𝒐𝒕𝒐𝒏𝒔 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Dark Measurements SiPM Thermostatic Chamber Amplifier board Output signal acquired by oscilloscope Pulses identification Scatter plot of Amplitude vs. inter-times 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Dark Analysis Direct CT Primary AP Delayed CT (C. Piemonte et. al., (2012) IEEE NSS/MIC Conf. Rec., N1-206) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

NUV-HD electrical parameters Gain > 1e6 25µm 30µm 35µm 40µm Rq ~ 1.5 MΩ to allow extended operational range 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 PDE at peak PDE at 400nm, T ~ 25°C , 1x1mm2 SiPM 25µm 30µm 35µm 40µm 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

T ~25°C, 1x1mm2 SiPM, 30µm Cell Pitch, 10V overvoltage PDE Spectrum T ~25°C, 1x1mm2 SiPM, 30µm Cell Pitch, 10V overvoltage PDE > 40% from 300 to 480nm 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Dark Noise Dark count rate vs PDE at 400 nm 25µm 30µm 35µm 40µm DCR fluctuates around these typical values DCR < 100 kHz up to the higher PDE in all cases 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Correlated Noise PDE at 400 nm CT = 10%, PDE > 40% 25µm 30µm 35µm 40µm 25µm 30µm 35µm 40µm Delayed Noise < 2% 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

4x4mm2 SiPM, LYSO Crystal 3x3x5mm3, T = 20°C NUV-HD in PET 4x4mm2 SiPM, LYSO Crystal 3x3x5mm3, T = 20°C 25µm 30µm 35µm 40µm (See S. Gundacker’s talk on 18/02/2016, medical applications session) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

NUV-HD for Cherenkov detection NUV-HD 30µm Cell Pitch PDE, 10V OV Cherenkov light spectrum in Earth’s atmosphere (See D. Simone’s poster, Poster Session B, #Board 99) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

NUV-HD at Cryogenic temperature A low-electric field NUV-HD version has been developed to reduce the tunnelling component of the DCR. > 7 orders of magnitude ! Standard field Low-field A 10x10 cm2 SiPM array would have a total DCR < 100 Hz! (See C. Savarese’s poster, Poster Session A, #Board 96) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Outline FBK Technology roadmap to HD Characterisation methods Characterisation results of NUV-HD Results in relevant applications Preliminary on NUV-HD low cross-talk Conclusions 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Low Cross-Talk technology Presented at NSS-MIC (2014) first development in RGB-HD technology 25µm 20µm HD LowCT Trenches filled with light absorbing material 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

The new trenches allow a reduction of about 25% at the same PDE NUV-HD LowCT 40µm Cell Pitch, PDE at 400nm Preliminary – 25% CrossTalk NUV-HD NUV-HD LowCT The new trenches allow a reduction of about 25% at the same PDE 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Conclusions High-Density technology was successfully applied to NUV-SiPMs investigating many cell pitches. Most important results: PDE > 60% at 400nm for 40µm Average DCR < 100 kHz/mm2 Cross-Talk at 10% with PDE > 40% at 400nm NUV-HD are suitable for many applications Promising results from LowCT technology were shown, further studies are still on going 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Performance of the latest prototypes of NUV-HD Silicon Photomultipliers G. Zappalà, F. Acerbi, A. Ferri, A. Gola, G. Paternoster, C. Piemonte, V. Regazzoni, N. Zorzi

Backup Slides

FBK SiPM in VCI 2013 Two technologies were presented: RGB and NUV SiPMs NUV-SiPM designed to detect Near-UltraViolet light SiPM NUV Cell pitch 50µm with 42% Fill Factor Primary Noise ~ 100 kHz/mm2 ECF (Excess Charge Factor) mainly determined by Delayed Correlated Noise 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 New substrate To reduce the delayed correlated noise (DeCT & APdiff)  different kind of substrate, with reduced carrier lifetime UV Photon Secondary Photons (Old) Substrate Diffusion length ~ 6µm (New) Substrate Diffusion length ~ 400nm We fabricated devices with the same layout and epitaxial layer (Old) Substrate DeCT & AP DiCT (New) Substrate (F. Acerbi et. al., IEEE T. Nucl. Sci., Vol. 62, n.3, 2015) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Performance with new substrate (Old) (New) (Old) New @6V OV Old @3V OV Greater maximum operating bias voltage Higher PDE 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Performance with new substrate The new Substrate has always a lower correlated noise probability Breakpoint Old-New Substrate 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

G. Zappala’ – Vienna Conference on Instrumentation 2016 Excess Noise Factor PDE > 45 % 25µm 30µm 35µm 40µm 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

NUV-HD in gamma-ray spectroscopy 𝒅𝑬 𝑬 𝟐 ∝ 𝟏 𝑷𝑫𝑬 𝑬𝑵𝑭 +… LYSO LaBr3 BGO 25µm 30µm 35µm 40µm ENF measured on SiPM without scintillator 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016

Energy Resolution of CeBr3 SiPM NUV-HD 4x4mm2, cell pitch 25µm CeBr3 4x4x11mm3 (crystal provided by J. Schmall and J. Karp) ~1% Energy resolution in range 5.5% – 7.0% Statistical error + crystal coupling ~ 1% (F. G. A. Quarati et. al., Nucl. Instr. Meth. A 735 (2013)) 16 Feb. 2016 G. Zappala’ – Vienna Conference on Instrumentation 2016