RD 50 CERN RD 50 Collaboration CERN RD
RD 50 CERN RD 50 Collaboration CERN RD 50 project: Main objective: Develop radiation hard semiconductor detectors that can operate beyond the limits of present devices for the luminosity upgrade of the LHC (Super. LHC) which will bring 10 times higher radiation levels. Three R&D strategies: · Material engineering - Defect engineering of silicon (oxygenation, dimers, …) - New detector materials (Si. C, …) · Device engineering - Improvement of present planar detector structures (3 D detectors, thin detectors, cost effective detectors, …) RD 50 Center of gravity · Variation of detector operational conditions - Low temperature operation - Forward bias operation Further key tasks: · Basic studies · Defect modeling and device simulation Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -1 -
RD 50 CERN RD 50 Collaboration Involvement of PH-TA 1 -SD in 2003: Alison (Doctoral Student since September), Christian, Maurice, Michael, Veronique • Direct involvement in the following research projects: • Oxygen dimer enriched silicon (Veronique, Michael) • Czochralski and epitaxial silicon as detector material (Alison, Michael) • Detector design development (Michael + outside collaborators) • Irradiations for RD 50, inclucing dedicated high flux run to reach 1016 p/cm 2 (Maurice, Michael) • Management of Collaboration: - Michael (CERN contact person and since July Deputy Spokesperson) - Christian (Budget holder and advice in many aspects) • Administration of members (270 Members from 51 Institutes), link to users office, web-pages, computer accounts, etc. • Organization of Workshops in May and November (~80 participants, ~ 35 talks) Since October help from Secretary Dawn Hudson … will continue for workshops in 2004. Changes in 2004: Alison (6 months), Christian, Maurice, Michael, Veronique (until end of April) • Conclude the dimer program, step out of the detector design development • Test of p-type silicon (also Czochralski) as detector material Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -2 -
RD 50 Czochralski silicon (CZ) • Very high Oxygen content 1017 -1018 cm-3 (Grown in quartz (Si. O 2)crucible) • High resistivity (>1 KWcm) available only recently (Magnetic CZ technology) • CZ wafers cheaper than FZ (RF-IC industry got interested) Irradiation of test-structures: • Only small change in Vdep • 1 • 1015 (190 Me. Vp)/cm 2 • 1015 (24 Ge. V/c p)/cm 2 • 5 • 1014 24 Ge. V/c p (10 Me. V p)/cm 2 • No type inversion (Sumitomo CZ) (However, type inversion observed for Okmetic MCZ after 5 • 1014 (10 Me. V p)/cm 2 ) • Leakage current and charge trapping as for FZ silicon • Very high oxygen content: Beware of thermal donors ! Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -3 -
RD 50 Defect Engineering: Oxygen Dimers in Silicon · Idea: Transform Oxygen into Oxygen dimers (O 2) Standard Si : V+O VO; Dimered Si : V+O 2 VO 2; deep acceptor (neg. charged) V+VO V 2 O V+VO 2 V 2 O 2 · How to produce silicon containing dimers ? · Co 60 -g or electron irradiation at 350ºC V+O VO; VO+O VO 2; I+VO 2 · Does it work ? Simulations: deep acceptor (but shallower than V 2 O) neutral in SCR ? • 11/2003 – First results … not as promising as thought. . Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -4 -
PH-TA 1 -SD Laboratory in Building 28 CV-IV Measurements Details: §Alessi probe station § Voltage source/current meter: Keithley 237, Keithley 2410 § LCR meter: Agilent 4263 B § Lab View program Planned improvements: § Automated temperature measurement § …improve flexibility of software TCT - Measurements Details (set-up still under development): §Pelletier cooled sample holder; nitrogen gas flow §Lasers 1060, 660 nm (produced by Maurice) §Voltage source: Keithley 2410 §Scope: Agilent Infinium §Pulse: Agilient 81104 A §Lab View program § … b source Summer Student 2003 Visitor Akhil Jhingan Michael Moll – Zürich, January 28, 2004 Alzbeta Helienek 2004 Alison Gouldwell-Bates
PH-TA 1 -SD … stop … no more than 5 slides !! Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -6 -
PH-TA 1 -SD Laboratories in 28 -2 Meeting room + RD 50 visitors Michael and Veronique Christian Lab borrowed to RD 39 Solid State Detector Laboratory Lab now used by Enrico Chesi (should be given back to us in very near future) § air condition (2 -019/2 -026) § electricity system renovated (2 -019/2 -026) § water (2 -019/2 -026) § compressed air (2 -019) Alison + visitors Michael Moll – PH-TA 1 -SDMeeting February 25, 2004 -7 -
PH-TA 1 -SD Laboratory in Building 28 Laminar Flow Bench Clean room class 10 in the lab? • less than 6 particles of size > 0. 3 mm per cubic feet measured • no particles of size > 0. 5 mm per cubic feet measured Deep Freezer Transportable deep freezer Michael Moll – Zürich, January 28, 2004
- Slides: 8