Charge Collection in CVD Diamond

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Charge Collection in CVD Diamond R. Kass Paris – Nov. 22, 2012 35

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Charge Collection in CVD Diamond. Paris – Nov. 22, 2012. R. Kass. 35. Radiation Damage - Basics. Charge trapping the only relevant radiation damage effect NIEL scaling questionable a priori E gap in diamond 5 times larger than in Si Many processes freeze out - PowerPoint PPT Presentation

Transcript of Charge Collection in CVD Diamond

Page 1: Charge Collection in CVD Diamond

Charge Collection in CVD Diamond

R. KassParis – Nov. 22, 2012 35

Page 2: Charge Collection in CVD Diamond

R. KassParis – Nov. 22, 2012 40

Radiation Damage - Basics

Charge trapping the only relevant radiation damage effect NIEL scaling questionable a prioriEgap in diamond 5 times larger than in Si Many processes freeze out Typical emission times order of months Like Si at 300/5 = 60 K – Boltzmann factor A rich source of effects and (experimental) surprises !

Radiation induced effect Diamond Operational

consequence Silicon Operational consequence

Leakage current

small &decreases none I/V = αΦ

α ~ 4x10-17 A/cm

HeatingThermal runaway

Space charge ~ none noneΔNeff ≈ -βΦ

β ~ 0.015 cm-1

Increase of full depletion

voltage

Charge trapping Yes Charge loss

Polarization

1/τeff = βΦβ ~ 5-7x10-16

cm2/ns

Charge lossPolarization

t

thttteff

vPN

)1(1

Page 3: Charge Collection in CVD Diamond

Summary of RD42 Test Beam Resultsfor CVD Diamond

R. KassParis – Nov. 22, 2012 41

Particle Energy Relative k

p 24GeV 1.0

800MeV 1.6-1.8

70MeV 2.5-2.8

25MeV 4.0-5.0

π 200MeV 2.5-3.0

k is relative damage constant