Apr.2015 MPPC and MPPC module for precision measurement ® ® Low-noise MPPC for precision measurement MPPCs and MPPC modules for precision measurement inherit the high photon detection efficiency of their predecessors and at the same time provide lower crosstalk, lower afterpulse, and lower dark count. What is MPPC? The MPPC (multi-pixel photon counter) is one of the devices called Si-PM (silicon photomultiplier). It is a photon-counting device using multiple APD (avalanche photodiode) pixels operR ating in Geiger mode. Although the MPPC is essentially an opto-semiconductor device, it has excellent photon-counting capability and can be used in various applications for detecting extremely weak light at the photon counting level. The MPPC operates on low voltage and features high gain, high photon detection efficiency, high-speed response, excellent time resolution, and wide spectral response range. It achieves the performance that is required in photon-counting at a high level. The MPPC is also immune to magnetic fields, highly resistant to mechanical shocks and the like, which are advantages unique to solid-state devices. NEW Features of MPPC for precision measurement When an MPPC detects photons, the output may contain false signals, namely afterpulse and crosstalk, that are separate from the output pulses of the incident photons. The MPPC for precision measurement maintains the high photon detection efficiency while providing low afterpulse, low crosstalk, and low dark count. Feature 1 Low crosstalk The pixel that detects photons may affect other pixels, making them produce pulses separate from output pulses. This phenomenon is called crosstalk. The MPPC for precision measurement employs a structure that suppresses the occurrence of crosstalk. This has drastically reduced crosstalk in comparison with previous products (rate of occurrence reduced from 44% to 3%). Crosstalk pulses S13360-3050CS (3 × 3 mm, 50 μm pitch) 50 mV 50 mV Previous product (3 × 3 mm, 50 μm pitch) 10 ns Feature 2 Low afterpulses While an MPPC detects photons, delayed signals may be output separately from the output pulses. These signals are called afterpulses. The MPPC for precision measurement provides low afterpulses. S13360-3050CS (3 × 3 mm, 50 μm pitch) Afterpulses 50 mV 50 mV Previous product (3 × 3 mm, 50 μm pitch) 10 ns Feature 3 Low dark count Improvement in material and wafer process technology has reduced the dark count down to approximately half that of previous products. See P.3 [ Dark count vs. overvoltage]. (Typ. Ta=25 °C, 3 × 3mm, Vov=3 V) Previous product 1 Mcps 2 S13360-3050CS 0.5 Mcps MPPC and MPPC module for precision measurement ® ® Feature 4 Widened operating voltage range The MPPC operation voltage Vop can be expressed as breakdown voltage (Vbr) + overvoltage (Vov). As the operating voltage is increased, the gain and photon detection efficiency improve, but at the same time, crosstalk and dark count, which are noise components, also increase. With previous products, the voltage dependency of noise components was high, and increasing the operating voltage caused a significant increase in noise components. On the other hand, with the MPPC for precision measurement, increase in noise components is suppressed even when the operating voltage is increased. Therefore, it can be used with high operating voltage (high gain and high photon detection efficiency). Gain vs. overvoltage Photon detection efficiency vs. overvoltage (Typ. Ta=25 °C) 3.5 × 106 Photon detection efficiency (%) NEW S13360-3050CS 3.0 × 106 Gain 2.5 × 106 2.0 × 106 1.5 × 106 Previous product 1.0 × 106 (Typ. Ta=25 °C) 60 5.0 × 105 0 50 Previous product 40 NEW S13360-3050CS 30 20 10 0 0 1 2 3 4 5 6 7 8 0 1 2 3 Overvoltage (V) 4 5 6 7 8 Overvoltage (V) KAPDB0307EA Crosstalk probability vs. overvoltage Dark count vs. overvoltage (Typ. Ta=25 °C) 50 (Typ. Ta=25 °C) 10000 Previous product 40 Previous product Dark count (kcps) Crosstalk probability (%) KAPDB0308EA 30 20 1000 NEW S13360-3050CS 100 10 NEW S13360-3050CS 0 0 0 1 2 3 4 5 6 7 8 0 Overvoltage (V) 1 2 3 4 5 6 7 8 Overvoltage (V) KAPDB0309EA KAPDB0310EA 3 Lineup MPPC modules Analog output type Built-in MPPC Photosensitive area C13365-1350SA S13360-1350CS □1.3 mm C13365-3050SA S13360-3050CS □3.0 mm TE-cooled type (MPPC for precision measurement) □1.3 mm Type no. Photo C13366-1350GA C13366-3050GA □3.0 mm Noise equivalent power Pixel pitch 50 μm 0.7 fW/Hz1/2 1.6 fW/Hz1/2 High-band Temperature Supply cutoff control voltage frequency See page 7 MHz Temperature compensation (non-cooled) ±5 V 8 7 MHz TE-cooled (-20 °C) ±5 V 9 0.15 fW/Hz1/2 50 μm 0.3 fW/Hz1/2 Digital output type Type no. Photo Built-in MPPC TE-cooled type (MPPC for precision measurement) C13366-1350GD C13366-3050GD Photosensitive area □1.3 mm □3.0 mm Pixel pitch Dark count Maximum Temperature Supply count rate control voltage See page TE-cooled (-20 °C) 10 2.5 kcps 50 μm 15 kcps 10 Mcps ±5 V Starter kit Type no. C12332 Photo Temperature control Supply voltage Temperature compensation (non-cooled) ±5 V See page Features · Evaluates any non-cooled MPPC (sold separately) · Includes C11204-01 power supply for MPPC · Measurable just by setting MPPC operating voltage from PC 18 MPPC Type no. Effective photosensitive area Pixel pitch S13360-1325CS 25 μm S13360-1350CS 50 μm S13360-1325PE □1.3 mm 25 μm S13360-1350PE 50 μm S13360-3025CS 25 μm S13360-3050CS 50 μm S13360-3025PE □3.0 mm 25 μm S13360-3050PE 50 μm S13360-6025CS 25 μm S13360-6050CS 50 μm S13360-6025PE S13360-6050PE 4 Photo □6.0 mm 25 μm 50 μm Package See page Ceramic Surface mount type Ceramic 12 Surface mount type Ceramic Surface mount type MPPC and MPPC module for precision measurement ® ® MPPC module ® Hamamatsu provides a full lineup of MPPC modules capable of measuring light over a wide range (10 orders of magnitude) from the photon counting region to nW (nanowatt) region. The modules contain an amplifier, a temperature-compensation circuit, a high-voltage power supply circuit, and other components needed for MPPC operation. You can use them simply by connecting them to a power supply (e.g., ±5 V). Hamamatsu offers a wide lineup of MPPC modules including cooled modules that give a low dark count and non-cooled modules with a temperature compensation function for stable measurement. We can also provide custom products that meet customers’ specifications. 5 Measurable light level range MPPC modules include two output types according to the incident light level (number of photons): analog output type and digital output type. (λ=450 nm) C11209-110 Non-cooled type/10 μm pitch Analog output C13365 series Non-cooled type/50 μm pitch type C13366-GA series TE-cooled type/50 μm pitch C13366-GD series TE-cooled type/50 μm pitch Digital output type Number of incident photons (cps) Incident light level (W) C13001-01 TE-cooled type/single pixel (fiber coupling type) 100 10-18 102 104 10-15 106 10-12 108 1010 10-9 1012 10-6 KACCC0678EE Selecting the digital output type or analog output type The output type (digital or analog) should be selected according to the light level incident on the MPPC module. The following output waveforms (a) (b) and (c) show MPPC output waveforms measured at different incident light levels and observed on an oscilloscope. The incident light level was increased in the order of (a), (b), and (c), starting from (a) at very low light levels. The output signal of (a) consists of discrete pulses. In this state, selecting the digital output type allows measuring at a higher S/N, where the signals are binarized and the number of pulses is digitally counted. Since the digital output type can easily subtract the dark count from the signal, the detection limit is determined by dark count fluctuations. As the light level increases, the output waveform consists of pulses overlapping each other [Figures (b) and (c)]. In this state, the number of pulses cannot be counted and the analog output type should be selected to measure the analog output and find the average value. The detection limit in the analog output type is determined by the dark current shot noise and the cutoff frequency of the readout circuit. Pulse waveform comparison (typical example) (a) Very low light level 6 (b) Low light level (c) High light level MPPC and MPPC module for precision measurement ® ® Block diagram Analog output type (C13365-1350SA) Amplifier Analog output MPPC Power supply for MPPC C11204-01 Temperature sensor ±5 V KACCC0675EA Digital output type (C13366-1350GD) TE-cooled type MPPC High-voltage controller High-voltage power supply circuit Temperature controller Microcontroller Amplifier Comparator circuit ±5 V Digital output KACCC0674EA Connection example (C13366-1350GA) Oscilloscope Analog signal cable Power cable (accessory) Light source Photons MPPC module Power supply (±5 V) Subject KACCC0770EA 7 MPPC module Analog output C13365 series Features Applications · Flow cytometry · Low-level light measurement Built-in MPPC for precision measurement · · High sensitivity in the short wavelength range · Low noise equivalent power · Fluorescence measurement · Built-in temperature compensation function · Compact and lightweight Absolute maximum ratings Parameter Supply voltage Operating temperature Storage temperature Symbol Vs Topr Tstg Condition Value ±6 -10 to +40 -20 to +70 No condensation No condensation Unit V °C °C Specifications (Typ. Ta=25 °C, λ=λp, Vs=±5 V, unless otherwise noted) Parameter Symbol Spectral response range Peak sensitivity wavelength Effective photosensitive area Pixel pitch Number of pixels Output voltage stability depending on temperature Photoelectric conversion sensitivity High band Cutoff frequency Low band Noise equivalent power Minimum detection limit Maximum output voltage Dimensions (W × D × H) λ λp - Condition Ta=25 ± 10 °C fc NEP - -3 dB Dark state Dark state C13365-1350SA Min. Typ. Max. 320 to 900 500 1.3 × 1.3 50 667 ±5 - - ±5 % 0.7 5 1.0 7 DC 0.7 2 4.9 1.3 - 0.7 5 1.3 - 1.4 4 - 1.0 7 DC 1.6 4.5 4.9 ×109 V/W MHz fW/Hz1/2 pW.r.m.s. V mm - Analog output MPPC Power supply for MPPC C11204-01 GND 100 mV +5 V KACCC0710EA 1 μs 8 nm nm mm μm - - Analog output waveforms High-speed amplifier Unit - 36 × 22 × 12.9 Block diagram Temperature sensor C13365-3050SA Min. Typ. Max. 320 to 900 500 3.0 × 3.0 50 3600 3.2 9 MPPC and MPPC module for precision measurement ® ® MPPC module Analog output C13366-GA series Features Applications · Built-in TE-cooled MPPC MPPC for precision measurement) (built-in · Low-level light measurement · Laser microscope · High sensitivity in the short wavelength range · Low noise equivalent power · Flow cytometry · Fluorescence measurement · Built-in temperature control function Absolute maximum ratings Parameter Supply voltage Operating temperature Storage temperature Symbol Vs Topr Tstg Condition Value ±6 -10 to +40 -20 to +70 No condensation No condensation Unit V °C °C Specifications (Typ. Ta=25 °C, λ=λp, Vs=±5 V, unless otherwise noted) λ λp - C13366-1350GA Min. Typ. Max. 320 to 900 500 1.3 × 1.3 50 667 C13366-3050GA Min. Typ. Max. 320 to 900 500 3.0 × 3.0 50 3600 Td -20 -20 Parameter Symbol Spectral response range Peak sensitivity wavelength Effective photosensitive area Pixel pitch Number of pixels Element temperature (setting temperature) Photoelectric conversion sensitivity High band Cutoff frequency Low band Noise equivalent power Minimum detection limit Maximum output voltage Dimensions (W × D × H) Condition fc NEP - 0.7 5 -3 dB Dark state Dark state - 1.3 - 0.7 5 0.3 0.8 - 1.0 7 DC 0.3 0.8 4.9 98 × 60 × 35 Block diagram nm nm mm μm °C 1.3 0.6 1.6 ×109 V/W MHz fW/Hz1/2 pW.r.m.s. V mm Analog output waveforms Temperature controller Amplifier High-voltage power supply circuit Microcontroller ±5 V Analog output KACCC0680EA GND 100 mV High-voltage controller TE-cooled type MPPC 1.0 7 DC 0.15 0.4 4.9 Unit 1 μs 9 MPPC module Digital output C13366-GD series Features Applications · Built-in TE-cooled MPPC built-in MPPC for precision measurement) ( · Low-level light measurement · Flow cytometry · High sensitivity in the short wavelength range · Low crosstalk · Fluorescence measurement · Low dark count · Low afterpulses Absolute maximum ratings Parameter Supply voltage Operating temperature Storage temperature Symbol Vs Topr Tstg Condition Value ±6 -10 to +40 -20 to +70 No condensation No condensation Unit V °C °C Specifications (Typ. Ta=25 °C, λ=λp, Vs=±5 V, unless otherwise noted) Parameter λ λp - C13366-1350GD Min. Typ. Max. 320 to 900 450 1.3 × 1.3 50 667 C13366-3050GD Min. Typ. Max. 320 to 900 450 3.0 × 3.0 50 3600 Td -20 -20 Symbol Spectral response range Peak sensitivity wavelength Effective photosensitive area Pixel pitch Number of pixels Element temperature (setting temperature) Photon detection efficiency Dark count Comparator output Afterpulse probability Crosstalk probability Comparator threshold level Dimensions (W × D × H) PDE - Condition Threshold level: 0.5 p.e. Threshold level: 0.5 p.e. 100 ns to 500 ns Block diagram 40 10 15 TTL compatible 0.1 0.1 1 3 0.5 to 8.5 (9 levels, adjustable) 98 × 60 × 35 - Digital output waveform High-voltage controller High-voltage power supply circuit Temperature controller Microcontroller Amplifier Comparator circuit ±5 V Digital output KACCC0674EA 1V TE-cooled type MPPC 40 2.5 - GND 10 ns 10 Unit nm nm mm μm °C 50 - % kcps % % p.e. mm MPPC and MPPC module for precision measurement ® ® Application examples of MPPC module Flow cytometry Fluorescence measurement Semiconductor laser Reagent MPPC module MPPC module Fluorescence Fluorescence Photodiode Sample Scattered light KACCC0664EA KACCC0668EB Major characteristics High photon detection efficiency, low afterpulse Major characteristics Wide dynamic range, High photon detection efficiency Suitable MPPC modules C13366-1350GA, C13366-3050GA C13366-1350GD, C13366-3050GD Suitable MPPC modules C13365-1350SA, C13365-3050SA C13366-1350GA, C13366-3050GA Particle diameter measurement Scintillation measurement Cancer position information Pair annihilation gamma-rays Light source MPPC module Subject MPPC module (array type) KACCC0598EA KACCC0764EA Major characteristics Wide dynamic range Major characteristics Low dark count, low afterpulse Suitable MPPC modules C13365-1350SA, C13365-3050SA Suitable MPPC modules C13001-01 Wafer surface inspection Semiconductor laser Distance measurement MPPC module MPPC module Semiconductor laser Wafer KACCC0665EA KACCC0666EA Major characteristics High-speed response, wide dynamic range Major characteristics High-speed response, wide dynamic range Suitable MPPC modules C11209-110 Suitable MPPC modules C11209-110 11 MPPC ® MPPC for precision measurement 12 MPPC and MPPC module for precision measurement ® ® MPPC for precision measurement S13360 series The S13360 series are MPPCs for precision measurement that inherit the high photon detection efficiency of their predecessors and at the same time provide lower crosstalk, lower afterpulse, and lower dark count. They are suitable for precision measurement, such as flow cytometry, DNA sequencer, laser microscope, and fluorescence measurement, that requires low noise characteristics. They are available in two types: ceramic package and surface mount. Pixel pitch: 25 μm S13360-1325CS, S13360-3025CS, S13360-6025CS S13360-1325PE, S13360-3025PE, S13360-6025PE Structure Parameter -1325CS 1.3 × 1.3 2668 Effective photosensitive area Number of pixels Package Window material Window refractive index Fill factor -3025CS 3.0 × 3.0 14400 Ceramic Silicone resin 1.41 S13360 -6025CS -1325PE 6.0 × 6.0 1.3 × 1.3 57600 2668 -3025PE 3.0 × 3.0 14400 Surface mount Epoxy resin 1.55 -6025PE 6.0 × 6.0 57600 -3025PE -0 to +40 -6025PE 47 Unit mm % Absolute maximum ratings Parameter Operating temperature*1 Storage temperature*1 Symbol Topr Tstg -1325CS -3025CS -20 to +40 S13360 -6025CS -1325PE -20 to +60 Unit °C °C Electrical and optical characteristics (Typ. Ta=25 °C, V=Vop, unless otherwise noted) Parameter Symbol Spectral response range Peak sensitivity wavelength Photon detection efficiency (λ=λp)*2 Typ. Dark count*3 Max. Crosstalk probability Terminal capacitance Gain Breakdown voltage Recommended operating voltage Temperature coefficient at recommended operating voltage λ λp PDE Ct M VBR Vop - -1325CS -1325PE 70 210 2 60 S13360 -3025CS -3025PE 320 to 900 450 25 400 1200 5 320 7.0 × 105 53 ± 5 VBR + 5 -6025CS -6025PE Unit nm nm % 1600 5000 1280 54 kcps % pF V V mV/°C *1: No condensation *2: Detection coefficient does not include crosstalk or afterpulses. *3: Threshold=0.5 p.e. 13 Pixel pitch: 50 μm S13360-1350CS, S13360-3050CS, S13360-6050CS S13360-1350PE, S13360-3050PE, S13360-6050PE Structure Parameter -1350CS 1.3 × 1.3 667 Effective photosensitive area Number of pixels Package Window material Window refractive index Fill factor -3050CS 3.0 × 3.0 3600 Ceramic Silicone resin 1.41 S13360 -6050CS -1350PE 6.0 × 6.0 1.3 × 1.3 14400 667 -3050PE 3.0 × 3.0 3600 Surface mount Epoxy resin 1.55 -6050PE 6.0 × 6.0 14400 -3050PE -0 to +40 -6050PE 74 Unit mm % Absolute maximum ratings Parameter Operating temperature*1 Storage temperature*1 Symbol Topr Tstg -1350CS -3050CS -20 to +40 S13360 -6050CS -1350PE -20 to +60 Unit °C °C Electrical and optical characteristics (Typ. Ta=25 °C, V=Vop, unless otherwise noted) Parameter Symbol Spectral response range Peak sensitivity wavelength Photon detection efficiency (λ=λp)*2 Typ. Dark count*3 Max. Crosstalk probability Terminal capacitance Gain Breakdown voltage Recommended operating voltage Temperature coefficient at recommended operating voltage λ λp PDE Ct M VBR Vop - -1350CS -1350PE 90 270 1 60 S13360 -3050CS -3050PE 320 to 900 450 40 500 1500 3 320 1.7 × 106 53 ± 5 VBR + 3 -6050CS -6050PE nm nm % 2000 6000 1280 54 *1: No condensation *2: Detection coefficient does not include crosstalk or afterpulses. *3: Threshold=0.5 p.e. 14 Unit kcps % pF V V mV/°C MPPC and MPPC module for precision measurement ® ® Dimensional outline (unit: mm) S13360-1325CS/-1350CS S13360-1325PE/-1350PE +0 0.4 ± 0.15 1.3 Photosensitive area 1.3 × 1.3 0.26 ± 0.15 1.3 2.1 1.3 5.0 ± 0.2 Photosensitive area 1.3 × 1.3 0.4 ± 0.15 Cathode indicator hole Silicone resin Photosensitive surface Epoxy resin 0.3 12 ± 1.0 0.85 ± 0.15 1.5 1.3 1.0 0.4 ± 0.15 2.625 6.0 -0.25 ϕ0.45 ± 0.05 Lead Photosensitive surface 3.0 ± 0.2 S13360-3025CS/-3050CS NC Cathode Anode NC 0.6 0.5 0.6 Lead material: Fe-Ni-Co alloy Lead processing: Au plating Tolerance unless otherwise noted: Chip position accuracy with respect to the package center: X, Y ≤ ±0.25 The resin coating may extend a m of 0.1 mm above the upper surfac KACCA0155EA Tolerance unless otherwise note Index mark 0.6 1.425 0.6 *Distance from chip center to pa KACCA0158EA S13360-3025PE/-3050PE 4.35 6.55 ± 0.15 0.925 ± 0.15 3.0 6.0 ± 0.5 0.3 Epoxy resin Photosensitive surface ɸ0.46 ± 0.05 ōŦŢť 1.45 ± 0.15 Silicone resin 3.0 3.85 0.33 0.25 ± 0.15 2.0 0.45 Photosensitive area 3.0 × 3.0 0.425 ± 0.15 3.0 5.9 ± 0.15 3.0 Photosensitive area 3.0 × 3.0 Photosensitive surface 1.0 2.2 KAPDA0156EA 1.0 KACCA0159EA S13360-6025PE/-6050PE 10.1 ± 0.1 7.35 6.0 0.25 ± 0.15 6.0 8.9 ± 0.1 Photosensitive area 6.0 × 6.0 6.0 Tolerance unless otherwi *Distance from chip cente 0.425 ± 0.15 S13360-6025CS/-6050CS Photosensitive area 6.0 × 6.0 Index mark 6.85 2.0 2.54 ± 0.15 4.25 0.3 1.45 ± 0.2 4.2 Photosensitive surface (10.5) Epoxy resin 6.85 0.8 0.425 ± 0.15 0.3 Photosensitive surface 2.0 ± 0.1 6.0 Silicone resin ɸ0.5 Lead 7.35 7.4 ± 0.2 4.6 Index mark: Cathode Lead material: Fe-Ni-Co all Lead processing: Au platin Tolerance unless otherwise Chip position accuracy with package center: X, Y ≤ ±0 The resin coating may exte 0.1 mm above the upper s KAPDA0157EA NC Anode Cathode NC Index mark Tolerance unless otherwise noted: ±0 *Distance from chip center to package KAPDA0153EA 15 Other MPPC product Other MPPC and MPPC module The product lineup containing MPPCs for general measurement (low afterpulse) is provided below. MPPC modules Type no. Photo C11209-110 Effective photosensitive area Pixel pitch Temperature control Output □1.0 mm 10 μm Temperature compensation (non-cooled) Analog TE-cooled (-20 °C) Digital C13001-01 Single pixel ɸ50 μm (fiber coupling type) MPPC array modules Array modules are available in various types. Contact us for detailed information. C12677 series: Analog type C12678 series: Photon counting type C12679 series: MCA (multi-channel analyzer) type 16 MPPC and MPPC module for precision measurement ® ® MPPC for general measurement Type no. Photo Photosensitive area Pixel pitch S12571-010C 10 μm S12571-015C 15 μm Package Ceramic □1.0 mm S12571-010P 10 μm S12571-015P 15 μm S12572-010C 10 μm S12572-015C 15 μm Surface mount type Ceramic □3.0 mm S12572-010P 10 μm Surface mount type S12572-015P 15 μm MPPC arrays (monolithic) Type no. Photo Photosensitive area per channel S12573-025C □3.0 mm Number of channels Pixel pitch Package 25 μm 2 × 2 ch S12573-050C Ceramic 50 μm CSP (chip size package) type Type no. Photo Photosensitive area per channel S12892PA-50 □2.0 mm S12641PA-50 □3.0 mm S12894PA-50 □6.0 mm S12642-0404PA-50 □3.0 mm Number of channels S12642-0808PB-50 Package 1 ch Connector - 50 μm Surface mount type 4 × 4 ch S12642-0404PB-50 S12642-0808PA-50 Pixel pitch Yes □3.0 mm 8 × 8 ch Yes 17 Related product Starter kit for MPPC C12332 series C11204-01 power supply for MPPC This is a starter kit for evaluating the MPPC. It consists of a power supply circuit board and a sensor circuit board. The power supply circuit board is equipped with a C11204-01 power supply for MPPC. The sensor circuit board has an MPPC socket with leads, which allows various non-cooled MPPCs to be implemented. This is a high voltage power supply that is optimized for driving MPPCs. Since it has a temperature compensation function, MPPCs can be driven stably even in environments subject to temperature changes. Features · · · · · · · Features Enables the evaluation of non-cooled MPPCs (sold separately) Comes with a socket for an MPPC Equipped with a high-accuracy, high-voltage C11204-01 power supply Adjustable operating voltage and temperature compensation coefficient Selectable amplifier usage Load resistance 50 Ω or 1 kΩ selectable Analog output · · · · · Wide output voltage range: 50 V to 90 V Low ripple noise: 0.1 mVp-p typ. Superb temperature stability: ±10 ppm/°C typ. High resolution settings (1.8 mV resolution) Serial interface Customized MPPC module Hamamatsu Photonics can provide the most suitable module product by combining its vast MPPC lineup with optical technologies, circuit technologies, and software technologies. Contact us for detailed information. 18 MPPC and MPPC module for precision measurement ® ® Principle of operation Image of MPPC’s photon counting Photon counting Light has the properties of both a particle and a wave. When the light level becomes extremely low, light behaves as discrete particles (photons) allowing us to count the number of photons. Photon counting is a technique for measuring the number of individual photons. The MPPC is suitable for photon counting since it offers an excellent time resolution and a multiplication function having a high gain and low noise. Compared to ordinary light measurement techniques that measure the output current as analog signals, photon counting delivers a higher S/N and higher stability even in measurements at very low light levels. Geiger mode and quenching resistor When an APD is operated at a reverse voltage higher than the breakdown voltage, a saturated output inherent to the APD device occurs (Geiger discharge) by input of light regardless of whether the light level is high or low. The condition where an APD operates at this voltage level is called Geiger mode. Geiger mode allows obtaining a large output by way of discharge even when detecting a single photon. Once Geiger discharge begins, it continues for as long as the electric field in the APD is maintained. To halt a Geiger discharge and detect the next photon, an external circuit outside the APD must lower the operating voltage. One specific example for halting the Geiger discharge is a technique using a so-called quenching resistor connected in series with the APD. This quickly stops avalanche multiplication in the APD because a drop in the operating voltage occurs when the output current caused by the Geiger discharge flows in the quenching resistor. The output current caused by Geiger discharge is a pulse waveform with a sharp rise time, while the output current when Geiger discharge is halted by the quenching resistor is a pulse waveform with a relatively slow fall time [Figure 5]. KAPDC0049EA Basic operation Each pixel in the MPPC outputs a pulse at the same amplitude when it detects a photon. Pulses generated by multiple pixels are output while superimposed onto each other. For example, if four photons are incident on different pixels and detected at the same time, then the MPPC outputs a signal whose amplitude equals the height of the four superimposed pulses. Each pixel outputs only one pulse and this does not vary with the number of incident photons. So the number of output pulses is always one regardless of whether one photon or two or more photons enter a pixel at the same time. This means that MPPC output linearity gets worse as more photons are incident on the MPPC such as when two or more photons enter one pixel. This makes it essential to select an MPPC having enough pixels to match the number of incident photons. Basic connection diagram +V 1 kΩ 0.1 μF Structure The MPPC structure is shown in the following figure. The basic element (pixel) of an MPPC is a combination of the Geiger mode APD and quenching resistor, and a large number of these pixels are electrically connected and arranged in two dimensions. MPPC Signal Amplifier KAPDC0024EB For the MPPC readout circuit, a current-to-voltage amplifier can be used as with previous semiconductor devices. The MPPC outputs high-speed pulse signals, but because the gain of the MPPC itself is high, there is no need to greatly increase the gain on the circuit side. This has an advantage that there is more freedom in circuit design. Geiger-mode APD pixel Quenching resistor KAPDC0029EA 19 MPPC and MPPC module for precision measurement ® ® MPPC is registered trademark of Hamamatsu Photonics K.K. (Japan, U.S.A, EU, Switzerland) Information described in this material is current as of March, 2015. Product specifications are subject to change without prior notice due to improvements or other reasons. This document has been carefully prepared and the information contained is believed to be accurate. In rare cases, however, there may be inaccuracies such as text errors. Before using these products, always contact us for the delivery specification sheet to check the latest specifications. The product warranty is valid for one year after delivery and is limited to product repair or replacement for defects discovered and reported to us within that one year period. However, even if within the warranty period we accept absolutely no liability for any loss caused by natural disasters or improper product use. Copying or reprinting the contents described in this material in whole or in part is prohibited without our prior permission. www.hamamatsu.com HAMAMATSU PHOTONICS K.K., Solid State Division 1126-1 Ichino-cho, Higashi-ku, Hamamatsu City, 435-8558 Japan, Telephone: (81) 53-434-3311, Fax: (81) 53-434-5184 U.S.A.: Hamamatsu Corporation: 360 Foothill Road, P.O.Box 6910, Bridgewater, N.J. 08807-0910, U.S.A., Telephone: (1) 908-231-0960, Fax: (1) 908-231-1218 Germany: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49) 8152-375-0, Fax: (49) 8152-265-8 France: Hamamatsu Photonics France S.A.R.L.: 19, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: 33-(1) 69 53 71 00, Fax: 33-(1) 69 53 71 10 United Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road, Welwyn Garden City, Hertfordshire AL7 1BW, United Kingdom, Telephone: (44) 1707-294888, Fax: (44) 1707-325777 North Europe: Hamamatsu Photonics Norden AB: Thorshamnsgatan 35 16440 Kista, Sweden, Telephone: (46) 8-509-031-00, Fax: (46) 8-509-031-01 Italy: Hamamatsu Photonics Italia S.R.L.: Strada della Moia, 1 int. 6, 20020 Arese, (Milano), Italy, Telephone: (39) 02-935-81-733, Fax: (39) 02-935-81-741 China: Hamamatsu Photonics (China) Co., Ltd.: 1201 Tower B, Jiaming Center, No.27 Dongsanhuan Beilu, Chaoyang District, Beijing 100020, China, Telephone: (86) 10-6586-6006, Fax: (86) 10-6586-2866 20