Irradiation Test of the Omegapix2 Digital Tier May 18-22, 2015, CERN Olivier Le Dortz, LPNHE Paris Juin 2015

O. Le Dortz Réunion Omegapix2 06/2015 Omegapix2 3D ASIC 3D Global Foundries 130nm technology Matrix of 96x24 pixels ( 2304 in total ) 1 Analog Tier + 1 Digital Tier Columns of different transistors types (6 kinds tested)

Configuration Shift Registers The parameters and results of each pixel of the analog and digital tiers are accessible via 5 shift registers (Analog Tier)Slow Control (Analog Tier)Analog Tier Probe (Digital Tier)Test input (Digital Tier)Digital Tier Probe (Digital Tier)Digital Data Readout O. Le Dortz Réunion Omegapix2 06/2015

Digital Tier Elementary Cell O. Le Dortz Réunion Omegapix2 06/2015 from pixel n TD InTest SR Test In(n) = SR Test Out(n-1) Test SR CLK SR Test Out (n) => SR Test In(n+1) 1 0 cmd_write (0:59) write_dataread_data cmd_read (0:59) 60 Elementary Cells array Start/Stop Detection CptEn Clk Mem Rst Mem 3-bit Gray Counter cpt(2:0) n Pixel n Data SR CLK Load Data SR SR Data In(n) = SR Data Out(n-1) SR Data Out(n) = SR Data In(n+1) cpt(0)cpt(1)cpt(2)

Trigger Sequence O. Le Dortz Réunion Omegapix2 06/2015

Store Time O. Le Dortz Réunion Omegapix2 06/ Injection of a pulse on each pixel input, at a specific position in the pipeline 2. Wait for a adjustable time 3. Read back each pixel at the specific position and check if the pulse is correctly read back 4. Increase the wait time until the data is not read back correctly 5. Display the maximum wait time with correct read back  Before irradiation, the data remain valid on the cell from 5ms to 25ms, depending on the transistor technology parameter

Irradiation Test O. Le Dortz Réunion Omegapix2 06/2015 Purpose: evaluate: the robustness of the circuit leakage currents, the evolution of storage time (several ms before irradiation) Conditions: Biased + Clocked during irradiation Online monitoring: Configuration Shift Registers Trigger Sequence => ~30 I/O to control, up to 40 MHz Control of the ASIC consumed current Doses Protons 2.5x10 15 p.cm 2 minimum

CERN Irradiation Site O. Le Dortz Réunion Omegapix2 06/2015 CERN-PS East Hall 24 GeV Proton beam, 12mmx12mm FWHM (ASIC= 5x5 mm²) Installation on Monday “Continuous” irradiation until Thursday. Integrated fluence=> 3, protons/cm 2

Acquisition Setup O. Le Dortz Réunion Omegapix2 06/2015 Driver Board FPGA+Interface 2 flat cables => IRRAD 9 220V CH 1 Ethernet Cable ETHERNET ~10 m Monitoring PC with LabVIEW software + Power Supply for IRRAD Board ZONE 2 (IRRAD 9) Beam ASIC Logic & I/O Irradiated Board OMEGAPIX2_IRRAD ZONE 4 ~7m ~30 I/O + Alim COUNTING ROOM Patch Panels 2m Proton Facility, PS East Hall (building 157) FPGA Board 220V Plug accessible Power Supply => Control Room Supervised Area

O. Le Dortz Réunion Omegapix2 06/2015 ETH & 220V  Counting Room FPGA Kit 2x40 pairs flat cables 10 meters long Irrad Board ~7V Power  Counting Room ETH  PC 220V Plug Irrad Power

Zone 2 (Proton Beam) O. Le Dortz Réunion Omegapix2 06/ cables plats 40 points Alim  Zone 4

Irradiated Board O. Le Dortz Réunion Omegapix2 06/2015 Beam center Chip inside package 5x5 mm2 Not mounted Voltage Regs 1.5 and 3.3V 6V+ to PP 2 flat cables to ZONE 4 LVDS Serial Transceivers Level convertors 1.5V  3.3V Not mounted ASIC QFP160 pin package Holes to support frame

Support de carte O. Le Dortz Réunion Omegapix2 3/03/2015 Support multi-carte du site Axe du faisceau Support LPNHE Carte irradiée

FPGA Board on Zone 4 O. Le Dortz Réunion Omegapix2 06/2015 Altera Nios II Stratix II Evaluation Board Ethernet 10/100 (to Counting Room) FPGA Stratix2S60 2 Expansion connectors 41 I/O each RAM DDR 32 MB ROM Flash 16 MB Flat Cables to Zone 2 Power Supply OMEGAPIX2_SANTACRUZ

Irradiation Run Summary From Monday 18 th to Thursday 21 st, total fluence of ~2.1E15 p/cm² During all the irradiation period, good functioning of the Configuration Shift Registers During the first hours of irradiation, continuous increase of the consumed current (until saturation) Strong reduction of the storage time when the beam was on When the board was put in park position or when the beam was off, could partially recover a functional operation of the pixel logic. But storage time reduced by factor > 10 ( less then 1 ms ) FPGA board: sensitive to radiation, even though in a “protected” area. Internet connection unstable. Had to restart the board frequently when the beam was on (not when off). From Thurday evening to Friday morning: additional irradiation up to ~3.0E15 p/cm². But after the beam was off, unable to access the FPGA board O. Le Dortz Réunion Omegapix2 06/2015

Conclusion To do list: Get the effective fluence figures from Irrad group Evolution of storage time wrt total fluence Mean value per pixel Histogram for each cell type... Check back, at CERN, if the FPGA board can be recovered/reprogrammed, in order to perform tests after the full dose (a spare FPGA board can also be used in case of full failure). What could have been improved: Automatic online monitoring of the power consumption No ground planes on the beam position (huge activation of the copper plane after several hours > 1mSv/h) FPGA board protection ? O. Le Dortz Réunion Omegapix2 06/2015