SOIPD Status e prospective for 2012. The SOImager2 is a monolithic pixel sensor produced by OKI in the 0.20 µm Fully Depleted-Silicon On Insulator (FD-SOI) process ; 5 5 mm 2 , 256 256 analog 3T pixels, 13.75 µm pitch , 1.8 V operational voltage; 8 different layouts; - PowerPoint PPT Presentation
SOIPD Status e prospective for 2012 The SOImager2 is a monolithic pixel sensor produced by OKI in the 0.20 µm Fully Depleted-Silicon On Insulator (FD-SOI) process; 55 mm 2 , 256256 analog 3T pixels, 13.75 µm pitch, 1.8 V operational voltage; 8 different layouts; Buried P-Well process implemented: the top electronics is effectively protected from the back-gate effect (shift of top transistor threshold when a biasing voltage is applied on the backside)
Transcript
SOIPDStatus e prospective for 2012
The SOImager2 is a monolithic pixel sensor produced by OKI in the 0.20 µm Fully Depleted-Silicon On Insulator (FD-SOI) process;
55 mm2, 256256 analog 3T pixels, 13.75 µm pitch, 1.8 V operational voltage; 8 different layouts;
Buried P-Well process implemented: the top electronics is effectively protected from the back-gate effect (shift of top transistor threshold when a biasing voltage is applied on the backside)
SOIPD - Consiglio di Sezione - Gruppo V – 11 luglio 2011
Test beam with 200 GeV - at CERN SPS •Three detectors arranged in one
cemented “doublet” (9 mm spaced) and one rotating plane (33 mm spaced). Single plane can be rotated up to 20° for slanted tracks and cluster studies.•The doublet is optically aligned with a better than 50 µm precision → easy and precise coincidence cuts in cluster recognition.
2
Beam
Cooling
Rotatingstage
Plane 2Plane 1
Plane 0
Tracks are reconstructed in two layers (doublet) and extrapolated in the third layer (singlet).
Excellent Spatial resolution and detection efficiency!
Single point resolution: (1.12±0.04) μm, for Vd ≥
50 V
Detection efficiency: >99% for Vd ≥ 50 V
SOIPD - Consiglio di Sezione - Gruppo V – 11 luglio 2011 3
Back-side soft X-ray irradiation• A set of sensor chips have been back-thinned to 70 μm using a grinding technique and post-processed
(P implantation followed by annealing) to create a thin entrance window (400-600nm) on the back-plane and anneal the crystal damage from the thinning;
• This process ensures good sensitivity to X-rays down to ∼1.5 keV and to electrons down to ∼9 keV. • The quantum efficiency for X-rays is studied on data collected at the beam-line 5.3.1 of the Advanced
Light Source (ALS) at LBNL. The thin, post-processed SOI sensor has been exposed from the backside to fluorescence radiation excited in various metal foils, in the energy range 2< E <9 keV and for 30V < Vd < 70V (Full depletion!)
X-ray quantum efficiency as a function of energy for three different values of Vd.
Cluster pulse height as a function of the energy of fluorescence X-rays obtained at Vd = 70 V.
Possible applications for pixellated sensors with large quantum efficiency for soft X-rays and low-energy particles, small pixels, fast readout and moderate energy resolution are:
• precision beam monitoring in linacs and storage rings with X-rays and soft electrons.
• electron microscopy• X-ray astronomy• …
Cu spectrum 8.04keV
Fe spectrum 6.4keV
SOIPD - Consiglio di Sezione - Gruppo V – 11 luglio 2011 4
Single Event Upset tests
256 shift register
(SR) cells, 13.75 µm
pitch
• Single Event Upset (SEU) micrometric sensitivity studies on the digital circuitry of the chip were performed at the Ion Electron Emission Microscope (IEEM) facility, located at the 15MV Tandem XTU-Accelerator of the INFN Legnaro National Laboratory
• A known logical pattern is written in and read back from the row selection shift register through dedicated pads during irradiation. Differences between the loaded and read-back pattern highlight a SEU occurred in the cells
250 MeV 79Br
Shift register layoutlatch latch
22.4m
• Four pairs of hot spots: each pair corresponds to a single SR cell and the two spots highlight the two Flip-Flop D structure of the cell.
• The different number of upset in the two columns of spots accounts for the dependence of the sensitivity from the logic state of the Flip-Flop
SOIPD - Consiglio di Sezione - Gruppo V – 11 luglio 2011 5
Activity for 2012
• Test of the new, larger chip built on Float Zone (FZ) SOI wafers with resistivity of several 1000 ·cm, recently made available from OKI; this chip can achieve full depletion on a thickness up to 500 m.
• Test beam at CERN SPS with - on a chip back-thinned and back-processed
• Test of a back-thinned and back-processed chip with low energy electrons (10-20 keV)
SOIPD - Consiglio di Sezione - Gruppo V – 11 luglio 2011 6
Personnel and budget request for 2012Personnel:D. Bisello 30%S. Mattiazzo 70%R. Rando 30%L. Silvestrin 30%M. Bagatin (DEI) 30%
