Andrei Nomerotski, University of Oxford 23 July 2008

1. Andrei Nomerotski, University of Oxford23 July 2008 ISIS3 specs

2. ISIS3 Goals • Choose process based on ISIS2 • Optimized pixel geometry • Readout architecture • Smaller pixel; goal: 20um x 20 um • Larger sensors : 1x1 cm2

3. Current load 10 μm 80 μm Source follower Pad Optimized Pixel Geometry • Imaging pixel dimensions do not coincide with pixel dimensions • ISIS2: two fold repeat • pixel 10x80 mm2; imaging pixel 20x40 mm2 • Square pixels • Three fold repeat in ISIS2 would give 27x27 mm2 imaging pixel

4. Current load 10 μm 80 μm Source follower Pad Readout Architecture • Column-wise with pixel addressing by Row Select • Need to move charge between memory cells as well • Same as Jessica • Each column has preamp & CDS • 16 columns are multiplexed to one ADC • 320 mm per ADC = good 8-bit ADC • Output of all ADCs serialized into LVDS outputs • Small total number of pads • Total data rate for ILC parameters 0.5 GB/sec Columns Serializer Multiplexer ADC

5. Pixel Size • ISIS2 : 10 x 80 mm2 • Buried channel width : 5 mm • Remaining 5 mm for connections/overheads • 3-phase CCD, gate width: 0.75 mm + 0.25 mm gap • ISIS2 design did not push limits • But big savings are not possible in 0.18 mm • Need to consider well capacity, now ~ 8ke • ISIS3: if pixel 8x65 mm2 then 22x22 mm2 imaging pixel

6. Sensor Dimensions • ISIS2 • Multi-project run 1cm x 1cm • four 5mm x 5mm ‘seeds’ •  1cm x 1cm possible in MP run • 2 cm x 2 cm is not a MP run, need to pay for the whole mask • Stitching at Jazz is expensive because nobody yet paid NRE for stitching at Jazz • NRE 100s k • No NRE ~20k

7. Comparison to Other Sensors • Jessica’s Rolling Shutter is similar to ISIS readout architecture • Column-wise with Row Select addressing