tailieunhanh - Lesson: Semiconductor detectors

Semiconductor detectors, structures, materials and engineering processes for Semiconductor detectors, Principles of operation and applications of Semiconductor detectors,. invite you to refer | General properties of semiconductor detectors HUVINETT 2012 Solid material higher density higher excitation probability Higher density compared to the gases Semiconductor detectors higher detection efficiency Short response time: ≈ ns!!! Operation under atmospheric and vacuum condition First applications: 1960, Si, Ge, CdTe, HgI2, . Energy required for generating 1 free electron 8th lecture scintillation detectors: Dr. Imre Szalóki 40 - 100 eV Counts Nuclear measuring methods E= keV NaI Xe prop. Si(Li) gaseous ionization detectors: 20 - 40 eV associate professor Head of Department of Nuclear Energetics semiconductor detectors: 1 - 2 eV No sensitivity to magnetic fields Budapest University of Technology and Economics Institute of Nuclear Techniques (BME NTI) Nuclear measuring methods/ 1. lecture Dr. Imre Szalóki., BME NTI Small-sizes of the volume 1 Nuclear measuring methods/ 1. lecture Energy Dr. Imre Szalóki., BME NTI 2 Band structure of solid materials Electrons in solid state: energy-band structure of the states E=0 Conductors Semiconductors Insulators Conduction-band ∆E ≈ – 2 eV Conduction band Valence-bands Gap ∆E > 5 eV ∆E =0 eV Valence band Electron-energy Conductors: Semiconductors: Dr. Imre Szalóki., BME NTI 3 10-3 - 109 Ωcm Insulators: Nuclear measuring methods/ 1. lecture 10-4 - 10-6 Ωcm 1010 - 1022 Ωcm Nuclear measuring methods/ 1. lecture Dr. Imre Szalóki., BME NTI 4 Migration of charges in pure and doped semiconductors Intrinsic: ni ≈ pi n-type: ni > pi donor Effect of the doping atoms to the energy-band structure p-type: ni > np p type Ge ≈ ·1011 e/cm3 nn >> np Nuclear measuring methods/ 1. lecture 5 Dr. Imre Szalóki., BME NTI eV/number of charge carriers pair /number The probability per unit time that an electron-hole pair is thermally Eg generated p (T ) = CT 3 2 e 2 kT band gap energy: Eg Boltzmann constant: k Absolute temperature: T n-type Conduction band Valence .

• Cơ khí - Chế tạo máy
• Semiconductor detectors
• General properties of semiconductor detectors
• Number of charge carrier pairs in semiconductors
• Structure of HPGe detector cooled with LN
• CCD line out read algorithm