11/05/2011Sensor Meeting, Doris Eckstein Status of Diode Measurements Measurements by:

11/05/2011Sensor Meeting, Doris Eckstein2 Continuation of characterization of received diodes of all available materials (IV/CV) FZ all thicknesses, MCz 200 Epi to come Characterization of irradiated structures: Material: FZ320N/Y, FZ200N/Y, FZ120N/Y Structures: 1xDiodeL and 1xDiodeS per material Total 12 per set Irradiation sets: –1e14n eq /cm² p only –1e14n eq /cm² n only –1e14n eq /cm² p plus 1e14n eq /cm² n TCT measurements, comparisons and evaluation of setups, systematics etc. TCT measurements as part of preparation for the next irradiation steps Organizational: EVO-meetings every 2-4 weeks to have some information exchange  agenda on same Indico page as this meeting Overview

11/05/2011Sensor Meeting, Doris Eckstein3 p+n p p p p p IV of p-irradiated and p+n-irradiated FZ Here the guard ring is not connected  To compare the volume current is not easily possible

CV of n-irradiated FZ- n-type V dep reduced Bulk seems inverted

CV and TCT (IR) of n-irradiated FZ- p-type p-spray FZ320Y IR laser

IV of n-irradiated FZ- p-type p-spray

11/05/2011Sensor Meeting, Doris Eckstein7 IV for MCz Current does not saturate Higher than in FZ Some variation seen

All but one Diodes have similar end- capacitance Pretty clean bulk compared to FZ CV for MCz

P-Spray has again dip in the Front CV for MCz n-type and p-spray

P-Stop looks pretty clean, except for that missing P-Stop CV for MCz p-stop

11/05/2011Sensor Meeting, Doris Eckstein11 TCT stability studies – uniformity vs. laser position (IR) Deviations in the collected charge for front window illumination (IR 1052 nm) up to 1.5 % around the mean No effect by rear side windows seen

11/05/2011Sensor Meeting, Doris Eckstein12 TCT stability studies – charge vs. sensor thickness (IR) Stability study for FZ320N diodes at different temperatures: 3% overall, 2% same wafer if corrected for thickness variations (from CV)

11/05/2011Sensor Meeting, Doris Eckstein13 TCT backside illumination (red) Reminder: for FZ material red laser was absorbed/reflected on rear side Now: MCz material FZ holes – reflection of red laser light seen MCz holes – no reflection of red Laser light  Red laser works for MCz Red laser signal 80% of charge on back side

11/05/2011Sensor Meeting, Doris Eckstein14 TCT on irradiated diodes FZ302 p-stop and p-spray compared Same irradiation type (protons) Same fluence but at different times  Very good agreement!  (as it should be!)

11/05/2011Sensor Meeting, Doris Eckstein15 CV comparison / default settings Measurements agree between KA and HH! Guard ring connected: end capacitance smaller, curve looks (nearly) as it should Guard ring not connected: Larger end capacitance, under- depleted region not linear in 1/C 2, the kink is slightly washed out Guard connected: thickness ok, N eff constant in bulk Guard not connected: N eff rising, thickness << 300μm  Default now is Guard Connected

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11/05/2011Sensor Meeting, Doris Eckstein17 Some statistics KIT: 94 diodes measured (small, large, some TCT) + 89new small diodes received CERN: 37 FZ diodes received (small, large) 29 measured with CV, some with TCT One baby sensor measured with edge-tct Hamburg University: 164 (+85 recently) received, 97 measured, some TCT

11/05/2011Sensor Meeting, Doris Eckstein18 Summary and Outlook Good progress in characterization of diodes with CV and IV TCT setups characterized and understood  Routine TCT measurements under way Preparation of next irradiation under way (complete CV, IV, TCT) In near future: -Finish preparation for irradiation (this + next week) -Analyze the results for irradiated diodes (put together data of different sites) -Try to see what happens to the defects found in the FZ sensors after irradiation -Discuss and define the procedure to measure trapping times -Continue with the characterization of Mcz, Epi,… -See, what the SIMS measurements on O-, C-content give -Have an Edge-TCT done for irradiated sensors (to be discussed) Thanks to all involved and have a look at the Indico page for more results

11/05/2011Sensor Meeting, Doris Eckstein19 94 meas+89new small ldiodes

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