Camera CCD in sviluppo allXUVLab per un esperimento su razzo, precursore dellesperimento UVC del Solar Orbiter Compact (72mm x 72mm x 50mm) Lightweight.

Presentazione sul tema: "Camera CCD in sviluppo allXUVLab per un esperimento su razzo, precursore dellesperimento UVC del Solar Orbiter Compact (72mm x 72mm x 50mm) Lightweight."— Transcript della presentazione:

1 Camera CCD in sviluppo allXUVLab per un esperimento su razzo, precursore dellesperimento UVC del Solar Orbiter Compact (72mm x 72mm x 50mm) Lightweight Fully vacuum compatible 4096 x 4096 maximum CCD format Three-stage Peltier cooler Two available thermal links between the CCD and the TEC (ΔT=-85°C/-60°C) Very low noise preamplifier stage (1.8 nV/ Hz r.m.s.)

2 Forme donda del CCD (fasi orizzontali in alto e verticali in basso) come appaiono ad uno strumento chiamato analizzatore di stati logici

3 Problemi dei rivelatori UV low UV sensitivity, unstable, not radiation hard, highly visible sensitive Photomultipliers CCD Photodiodes (a-Si, treated Si, Al) Photodiodes (a-Si, treated Si, Al) Micro-Channel Plates high voltage, hygroscopic photocathodes, unstable gain, operated in UHV low UV sensitivity, unstable, not radiation hard, highly visible sensitive high voltage, 110 nm, low fluxes, dark current

4 Ideal UV detector for space visible blindness very low noise high sensitivity to XUV photons chemical stability radiation hardness Requests

5 Specifiche per i rivelatori del Solar Orbiter Solar blindness < 10 -7 Operating temperature ± 50°C Frame rate 1000 s - 1 Frame format 2K 2K Pixel size < 20 m Radiation hardness 50 Krad Weight 1 kg Common specification requirements for the imaging and spectroscopic instruments for remote sensing are Photon fluxes ( counts/s/px) Imaging 10 3 Spectroscopy 10 2 -10 3 3-D spectroscopy 10 5 Photon fluxes ( counts/s/px) Imaging 10 3 Spectroscopy 10 2 -10 3 3-D spectroscopy 10 5

6 Rivelatori UV disponibili Photon Counting MCP + XDL MCP + APS MCP + CID Advantages Photon counting Solar blindness Radiation hardness Spatialised Operating @ T amb Disadvantages Efficiency < 30% High voltage biases Weight Spatial resolution (centroid required) External electronics (to be shielded!) Charge integration None! CCD is not rad-hard

7 Alternativa: nuovi materiali fotosensibili E g = 5.5 eV dark current < 1 pA visible rejection (ratio 10 -7 ) high EUV sensitivity Highly radiation hard Chemical inertness Mechanically robust (high Young modulus) High electric charge mobility = fast response time Low dielectric constant = low capacitance Diamond & nitrides are appealing materials for the EUV photon detection. Their main properties are hereafter sumarized :

8 Rivelatori a diamante Device area: 6 6 mm 2 Thickness: 40 µm Grain size: 20 µm Sensitive area 4 mm 2 Interdigitated contacts spacing 20 m thickness 0.1 m electrode width 15 m No thermal annealing back contact 25 mm 2

9 Dark current

10 Stabilità e risposta temporale T off = 30 %

11 Quantum Efficiency [1] Naletto, Pace et al, 1994 [2] Wilhelm et al.,1995 [2] [1] Diamond efficiency Comparison with other detectors E. Pace et al., Diam. Rel. Mater. 9 (2000) 987-993.

12 Diamond – Responsivity Dark current @ room temperature V bias = 30 V

13 Our proposal: flip-chip CMOS imager Select the most appropriate sensitive material Exploit the advantages offered by the CMOS technology to fabricate system- on-a-chip detectors Join the best material and on-chip CMOS electronics by means of the consolidated flip-chip technology (applied to IR photon and particle detection) The idea

14 Diamond bump-bonded detector Incident radiation Open electrode CMOS imager Sensitive layer Pixel array 12.5 m

15 Applicazioni attuali alla fisica delle particelle

16 Advantages of flip-chip technology High responsivity Visible rejection Available technologies Frame format and pixel size in the spec On-chip read-out electronics Radiation hardness Compact detector (reduced weight) Low power consumption High frame rate Windowing EUV sensitive layers bump-bonded on CMOS imagers could have many appealing features, such as: