Digital SiliconPhotomultiplierBreakthrough in fully digital photon counting

The key to this breakthrough lies in Philips’ ability

to combine high performance single-photon

avalanche photodiodes and low-voltage CMOS logic

on the same silicon substrate using a conventional

CMOS process technology. This integration enables

true digital photon counting without the need for

noise-sensitive off-chip A/D conversion.

Potential application areas• Medical imaging

• High-energy physics

• Analytical instrumentation

• Safety and security applications

Philips’ highly innovative digital silicon

photomultiplier technology has the

potential to create a new class of light

detectors for ultra-low light levels down

to single photons. By integrating both

the sensor and the data processing into

a single silicon chip, it will enable faster

and more accurate photon counting in a

wide range of applications where ultra-

low light levels need to be measured.

Application benefits• Sensitivity - Low dark count level• Speed - Excellent timing resolution• Robustness - Against electromagnetic interference - Low sensitivity to temperature variations• Dark count reduction due to the possibility of disabling individual cells

For system manufacturers• Integrated electronics simplifies system integration (fully digital interface)• Lower system cost• Low power consumption• Scalability of the detector area• Customized detector and modular design

Digital Silicon Photomultiplier

How it worksWorking principle of a digital silicon photomultiplier

PartnershipAs one of the underlying principles behindits policy of open innovation, Philipswelcomes development partners withapplication expertise to fully exploit themarket potential of its new digital siliconphotomultiplier technology.

Figure 1a: One array comprises 16 dies (8x8 pixels)

Figure 2: First photon hits the sensor, integrated photon counter increases to 001 and integrated timer measures arrival time of first photon per die.

Figure 4: The chip has measured the 3 photons that have hit the sensor during the desired length of the detection process.

Figure 1b: One die comprises 4 pixels

Figure 3: Second photon hits the sensor, the integrated photoncounter increases to 002.

Figure 5: At the end of the detection process, the values of the integrated photon counter and timer can be read out via a digital interface.

Figure 1c: One pixel Figure 1d: Photo of a die

SpecificationsPhysical characteristics DPc6400-22-44 DPc3200-22-44OuteR DImenSIOnS 32.6 x 32.6 mm2 32.6 x 32.6 mm2

PIxeL PItCh (h x V) 4.0 mm x 4.0 mm 4.0 mm x 4.0 mm

PIxeL ACtIVe AReA 3.9 x 3.2 mm2 3.9 x 3.2 mm2

numbeR Of CeLLS PeR PIxeL

CeLL SIze

639659.4 x 32 μm2

320059.4 x 64 μm2

SPeCtRAL ReSPOnSe RAnge 380 nm – 700 nm 380 nm – 700 nm

PeAk SenSItIVIty WAVeLength (λP) 420 nm 420 nm

PhOtOn DeteCtIOn effICIenCy (PDe) @ λP (PIxeL LeVeL) 30 % 40 %

PIxeL fILL fACtOR (ALReADy InCLuDeD In PDe) 54 % 74 %

tILe fILL fACtOR 75% 75%

DARk COunt RAte (95% CeLLS ACtIVe) < 5 mhz / pixel at room temperature

< 7 mhz / pixel at room temperature

OPeRAtIOnAL bIAS VOLtAge 27 +/- 0.5 V 27 +/- 0.5 V

temPeRAtuRe DePenDenCe Of PDe -0.33%/°C in the range of 15°C - 25°C

-0.33%/°C in the range of 15°C - 25°C

IntRInSIC tImIng ReSOLutIOn* 44 ps 44 ps

Environmental ParametersParameter DPc6400-22-44 DPc3200-22-44StORAge temPeRAtuRe 0°C to +70°C 0°C to +70°C

OPeRAtIng temPeRAtuRe 0°C to +20°C 0°C to +20°C

Key Features• 8 x 8 pixel array

• Single photon counting capability

• Integrated time-to-Digital converters

• first photon trigger (configurable;

up to 4th photon trigger)

• excellent timing resolution

• fully digital interface

• four side tileable

• Configurable validation network for

effective dark-count suppression

• Low disturbance by external

magnetic fields

DPC6400-22-44 / DPC3200-22-44

Preliminary Short Data Sheet

*measured with pico second laser pulse with approx. 1000 photons.Please note: All data is preliminary and subject to change without prior notice!

Digital Silicon Photomultiplier

Dark count rate map: Option to physically disable arbitrary, user-selectable cells on the sensor.

DPC Array

typical photon detection efficiency of DPC6400-22-44 typical photon detection efficiency of DPC3200-22-44

may

201

2

Description of Operationthe DPC6400-22-44 and the DPC3200-22-44 (tile) consist of 8 x 8 pixels arranged on 4 x 4 chips (dies). Each chip contains 2 x 2 pixels. Each pixel has access to two logic blocks to record the energy and the timestamp of a hit. The determination of the hit energy is done by recording the number of detected photons, i.e. broken-down cells, by means of an accumulator. The timestamp is generated by a combination of a ‘fine’ counter (time-to-digital converter, tDC) and a coarse counter (synchronous to the system clock). the SPI flash memory contains all die related information needed for calibration/correction of the photon count and timestamp. the tile fPgA controls/programs all individual dies, collects all the events for each die and performs post- processing to generate a full timestamp and photon count value for each event.

Performance Characteristics

Dimensions

Preliminary Short Data Sheet

ContactFor further information, please contact:Philips Digital Photon CountingPauwelsstraße 1752074 Aachen, germanyPhone: +49 241 969 79130Fax +49 241 969 79191e-mail: digitalphotoncounting@philips.comwww.philips.com/digitalphotoncountingPlease note: All data is preliminary and subject to change without prior notice!

Backside of sensor Frontside of sensor Dies on tile (front) Pixel (front)

Single pixel block diagram

Digital Silicon Photomultiplier