Measurements on bare ASIC and full detector. M.Borri STFC Tests - PowerPoint PPT Presentation

Measurements on bare ASIC and full detector. M.Borri STFC ◮ Tests on bare asics v2. ◮ Tests on full detector.

Characterization overview. Test on bare asic: Testing ◮ Sensor electrical test I-V measurement Standard tests are completed on second board using asic v2: e-mode and h-mode. Front-end tuning Threshold ◮ e-mode tests presented on 21 July 2014. Shaper ◮ h-mode tests present today, see my other set of Calibration slides. ◮ Front-end electrical test: Noise and noisy channels Board 2 did not show any particular signal of fault. ◮ It also never locked up (improvement w.r.t. Cross-talk board1). Timewalk and jitter Tests on full detector: Detector performance Charge collection efficiency ◮ Detector received at DL on Thursday. Signal-over-noise ◮ Detector is connected and sits in air (lab.T9). ASIC ◮ Electrical tests are ongoing: IV and noise vs CMOS process AMS 0.35 µ m channel. Power consumption < 1.5 W/ASIC ◮ Memory of DAQ allows for test of 1 side only: n Channels per chip 128 side (or even-side). Data rate < 5 kHz/channel Energy range 0-50 MeV ◮ Detector is working with E-th at 0xe0. Time stamp 100 MHz Other: Sensor ◮ Type double sided New test has been implemented. Bulk doping n-type ◮ Measures time-stamp (TS) jitter as a function of Bulk thickness 300 µ m the threshold of TS discriminator. Strip pitch 50 µ m ◮ Need practice to possible optimization. Strip width 38 µ m Strip stereo angle 16.2 o Leakage current per strip 3.25 nA/cm ( < 100 nA) Strip capacitance 2.3 pF/cm ( < 80 pF)

Full-detector tests: IV A] A] µ IV characteristic IV characteristic Ileak vs time Ileak vs time µ 41 [ 45 [ 40.9 40 35 40.8 30 40.7 25 40.6 20 40.5 15 40.4 CHs OFF 10 40.3 5 CHs ON 40.2 0 0 10 20 30 40 50 60 70 80 90 10 20 30 40 50 60 70 80 90 [V] [min] ◮ IV different from that measured at Liverpool. ◮ It shows an increased ohmic behavior. ◮ Temperature effect: 30deg (from pt100), 43deg (from Ileak). ◮ If temperature effect then pt100 is not measuring the right temperature. ◮ Other possibility would be mechanical damaging of sensor. ◮ No thermal run away.

Full-detector tests: noise vs strip length. Noise Vs StripLenght (Side0, PeakTime1.0us) Noise Vs StripLenght (Side0, PeakTime4.0us) Std.Dev.[ADC] 10 Std.Dev.[ADC] 10 9 9 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 0 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 Channel[a.u.] Channel[a.u.] Noise Vs StripLenght (Side0, PeakTime7.5us) 10 Std.Dev.[ADC] ◮ Input capacitance ∝ strip length. 9 ◮ I leak ∝ strip length. 8 ◮ 7 Noise increase for longer strips. 6 ◮ Increasing shaping time makes the noise lower and 5 homogenus across the channels. 4 N.B. chain 1 (n side) is not working. 3 2 1 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 Channel[a.u.]

New test: time-stamp jitter. Mean Mean Std.Dev. Std.Dev. 1200 Mean [10ns] Std.Dev. [10ns] 500 1150 1100 400 1050 300 1000 950 200 900 100 850 800 0 130 135 140 145 150 130 135 140 145 150 TS-th [DN] TS-th [DN] ◮ GOAL: measure the time-stamp jitter. ◮ MEASUREMENTS: Loops over all the channels. Only one channel is powered up at each time. For this channel, loop over the time-stamp threshold. Inject N pulses for each time-stamp threshold. Each time calculates pulse period: time stamp new - time stamp old . N.B. At the moment, the mean is not the value of the real period. It requires to add an offset. TEST OUTCOME: Std.Dev. decreses by increasing the threshold: expected. As a default value we use 144dec (0x90).