A pnCCD detector system for high speed optical applications

Präsentation zum Thema: "A pnCCD detector system for high speed optical applications"—  Präsentation transkript:

1 A pnCCD detector system for high speed optical applications
Semiconductor Detector Workshop 2005 Taormina / June 19 – 24, 2005 A pnCCD detector system for high speed optical applications Robert Hartmann 1 , Hubert Gorke 2 , Norbert Meidinger 3 , Heike Soltau 1 and Lothar Strüder 3 PNSensor GmbH, Römerstraße 28, München, Germany Forschungszentrum Jülich, Leo-Brandt-Straße, Jülich, Germany Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, Garching, Germany

2 Overview • Principles of pnCCD Optical properties • Detector format and geometry • Readout and data acquisition • Measurements and Performance Summary and outlook

3 Principles of the pnCCD
Fully depleted 3-phase CCD Back side illuminated Cooled to -40º C º C (typ.) Small detector capacitance ≈ 25 fF → low noise One integrated FET per channel Channel-Parallel-CCD → fast readout p-implanted registers High radiation hardness

4 Overview • Principles of pnCCD Optical properties • Detector format and geometry • Readout and data acquisition • Measurements and Performance Summary and outlook

5 pnCCD for optical applications
back illuminated detector unstructured entrance window results in a homogeneous responsitivity application of an ultra-thin rectifying implant leads to a high QE in the blue and UV region easy to apply an anti-reflective coating entire detector volume of 450µm is radiation sensitive high quantum efficiency in the red and NIR region fringing effects are negligible small detector capacitance high signal to noise ratio • highest electric field at readiation entrance side narrow PSF back illuminated detector unstructured entrance window results in a homogeneous responsitivity application of an ultra-thin rectifying implant leads to a high QE in the blue and UV region easy to apply an anti-reflective coating entire detector volume of 450µm is radiation sensitive high quantum efficiency in the red and NIR region fringing effects are negligible small detector capacitance high signal to noise ratio • highest electric field at readiation entrance side narrow PSF

6 Measured and modelled reflectivity of CCD entrance window
: Measured data : Model of Si-SiOx-SiO2 : Model of pure Si-SiO2 Interface

7 Internal quantum efficiency

8 Measurement of optical response at room temperature
Optimized for CsI(Ti) scintillator readout (λ = 548nm) Standard entrance window, consisting of a thin SiO2 layer Reflectivity of Silicon resp. Si/SiO2 ≈ 30% Use layer stack of SiO2/Si3N4 as ARC Technology allows to taylor responsitivity over a wide wavelength range Technological compatible ARC: High QE in visible, maximum at 580nm Optimum QE in NIR region Blue and UV optimized 300nm)

9 150 mm Wafer of recent fabrication

10 Fringing effects due to multiple light reflection between detector front and back side

11 Overview • Principles of pnCCD Optical properties • Detector format and geometry • Readout and data acquisition • Measurements and Performance Summary and outlook

12 Schematic layout of 51 mm CCD with double-side readout

13 51mm pnCCD with a double-sided readout, mounted onto a ceramic substrate
image area = 13.0×13.5 mm2 chip area = 16.0×31.0 mm2 51 mm pixel size 256×264 pixel plus 2×4 “light insensitive” columns readout transfer to both sides

14 Performance overview Fast transfer time
25 μs/image (split to both detector sides) CTI ≈ 1 · → total charge loss < 0.15 % Charge handling capacity > 105 e¯ / pixel Fill factor 100 % Readout time Normal mode: 15 μs/row, i.e. 500fps Fast mode: μs/row, i.e. 1000fps Pixel rate 70 Mpixel/s , split on 8 readout nodes Readout noise Normal mode → < 500fps : 1.8 e¯ (rms) Fast mode → 1000fps : 2.3 e¯ (rms) Transfer binning (×2, ×3, ×4) 2000, 3000, 4000fps : 2.3 e¯ (rms) Operating temperature - 55º C for all measurements above Dynamic output range 70 dB

15 Brief overview • Principles of pnCCD Optical properties • Detector format and geometry • Readout and data acquisition • Measurements and Performance Summary and outlook

16 CAMEX Amplification- and Readout-Chip
Multi-correlated double-sampling filtering (MCDS) Signal processing of all channels in parallel (132) Serialized readout parallel to analogues signalprocessing Selectable gains and operating modes Electronic noise contribution less than 1 e- Readout-speed per node up to 10MHz (i.e. 6.6µs per line on two readout nodes)

17 Data acquisition and real-time correction
1000 frames / sec. 264 lines / frame 264 pixel / line 70 Mpixel / sec. !!! 140 MB/sec. Split on 4 DAQ boards á 17.5 Mpixel / sec. 2×14 bit flash-ADC Pipelined data processing in fast FPGA processor for real-time data correction and reduction Output of 1st CCD line is available with a latency time < 40 ms constructing frame MIP and cluster analysis latency ~ 1.2 msec Example for a SH detector:

18 30 in total, free-to-ground, PC controlable, incl. monitor
Overview Camera Controller cPCI-Bus 19’’ crate double height Power-Supplies 30 in total, free-to-ground, PC controlable, incl. monitor Fiber Interface ADC-Modul 1 ADC-Modul 2 ADC-Modul 3 ADC-Modul 4 Sequencer PS-Control 32 2 2 2 2 80 MB/s 300m Front-End-Boards (incl. clock-drivers) CAMEX pnCCD-Chip Linux PC

19 Data acquisition electronic system
Sequenzer 1 … 4 ADC-Boards á 2 ADCs Spare for Voltage Controller Optical Interface

20 Overview • Principles of pnCCD Optical properties • Detector format and geometry • Readout and data acquisition • Measurements and Performance Summary and outlook

21 Spectroscopic soft X-ray performance of pnCCD
Operating Temperature = -55° C Overall noise contribution : 2.3 e- All events reconstructed FWHM for singles: 45eV

22 Low and uniform noise performance
66×264 pixel, ⅛ of 51mm CCD (“worst” section) 1 of 4 output nodes on one readout side image plus storage area operating temperature = -55°C “1000fps” - timing scheme Mean noise = 2.3 electrons (rms) 98.8% of all pixel exhibit less than 2.7 e- noise 100% are below 3.1 e-

23 Increase readout speed for dedicated applications
Repetively readout of n lines with signal merely transfer with no readout lines w/o signal readout of next n lines and so on … 40×40 SH with 5×5 Pixel: 1kHz → 1.3kHz frame rate .

24 Conclusion pnCCDs exhibit a high quantum efficiency from the optical to NIR region device with 256×264 (13.0x13.5mm2) image size and a double side readout was successfully tested for a frame rate of 1000 fps total readout noise of 2.3e- (RMS) was achieved in this mode at an operating temperature of -55ºC binning in transfer direction allows 2kHz, 3kHz, ... frame rates with same noise figures due to very low leakage current low and homogeneous noise performance over entire area (no bright or hot pixel, even at higher temperatures) optical photon counting possible down to ≈ 8 γ/pixel

25 Back to the beginning Long term stability of pnCCD detector aboard XMM-Newton (1999): Total area = 36cm2 all 12 Sub-CCDs are still operating same operating parameters (T = -90°C) quantum efficiency unchanged noise performance unchanged slight radiation damage as expected: CTI ← 6 cm → FWHM after 5 years in orbit: Al-K (1.5 keV): 110 eV → 111 eV Mn-Kα (5.9 keV): 155 eV → 160 eV

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