New detectors are needed! Prototype Characterization The PERCIVAL soft X-ray detector. J. Correa on behalf of the Percival Collaboration a,b,c,d,e,f Matter and Technologies Detector Development Motivations and Goals Detector Structure Attenuation Length of Photons in Si and SiO2 1m Water Window Other FELs FLASH ADC digital out sampling & gain selection address pixel matrix 12+1 bits 2 bits backthinned (~12um) & -doped epi Si e- handling wafer partially-pinned photodiode nmos -in p-well (avoid parasitic collection) shallow doping Detecting photons in the water window is challenging (sub-µm absorption lengths for Si and SiO2) Entrance window needs to be minimized, or detector response risks being dominated by higher harmonic photons Brilliance of photon sources increases Detectors are required capable (at the same time) of: high dynamic range 1-photon discrimination New detectors are needed! PERCIVAL: a collaboration between DESY, STFC, ELETTRA, DLS and PAL. Primary energy range: <250 eV to 1 keV Single photon sensitivity High dynamic range. 100% fill factor (back-illuminated, back-thinned) Large array ( 2M) of small pixels (27um) High and uniform QE. Prototype Characterization syncrotron beam pinhole Percival diffraction through a circular aperture: Noise for low flux condition ≤ 15 e-. Noise for high flux condition < Poisson limit. Beam-time campaigns at: PETRA (P04) Elettra (Twinmic, CiPo) DLS (I10) BESSY (PTB) prelim optical/Fe55 tests at Phoebe XFEL setup and of course in CFEL Lab Response to low energy photons (92eV) matches expectations response is dominated by 1st harmonic photons negligible entrance window scaling up from prototype to full P2M scaling up from prototype to full P2M Full well: 3.5 Me- ~ 50k photons @ 250 eV Full P2M System, under test Carrier board (re-configurable clocks &control) PowerBoard (bias & monitoring) Mezzanine board (stream-out data //10Gb ports.) DAQ interface (deep switch &multiple DELL R630) VirtualHDF5 dataset data organization (because a detector does not ends at its ethernet port) approx scale to the prototype dimension approx scale to the prototype dimension P2M sensor Monolithic Active Pixel Sensor 2 Megapixels (~ 4x4 cm2 imaging area) 27um pixel pitch, embedded lateral overflow circuitry (auto-adaptive gain to incoming flux, per pixel, real time) 2 side-buttable: cloverleaf arrangement of 4 modules around a central hole possible up to 300 frame/s (prelim. tested up to 100 f/s) on-chip ADCs (13+2 bits): all-digital output 1st image acquired on P2M sensor (visible light, 660nm) Backthinned P2M (soft X-ray detection) expected spring 2018 I know it now looks messy at the moment: what do you expect from a lab 1st setup? a) b) c) d) e) f)