Topic:New highly-sensitive semiconductor materials for IR region: CdTe and CdHgTe crystals doped with 3d elements
Speaker: Professor Yuriy P. Gnatenko, Institute of Physics of National Academy of Sciences Kiev, Ukraine
Date & Time: Thursday, September 6, 2001, 1:00 P.M
Place: Room 140 VMC
The nature and energy structure of impurity and intrinsic defects including the formation of an isotropic impurity centers are determined in bulk n-type Cd1-xHgxTe (x <= 0.05) crystals doped with V atoms (N=1019 cm-3). The Combined energy-level diagram showing d - d* internal transitions and ionization levels of V impurity centers and intrinsic defects in CdTe:V and Cd1-xHgxTe:V crystal is presented. For the first time the photorefractive properties are studied for CdTe:Ti as well as Cd1-xHgxTe doped with Ti and V atoms using pulsed radiation of a 1.06 µm Nd:YAG laser. Carrier transport and trapping process in high-resistivity CdTe:V crystals have been investigated using a time-of-flight method under a constant monochromatic illumination. Since above-mentioned doped crystals are semi-insulating ( rho=108-109 Omega-cm) they can also be considered as new promising X-ray and gamma-radiation detector material
Prof Yu. Gnatenko is the head of the Department of Optic and Spectroscopy of Crystals of Institute of Physics, National Academy of Science. He received his MS and Ph.D. from Lviv State University Lviv, Ukraine in 1965, and 1970 respectively. Prof. Gnatenko is the project manager of International supported program (USA, Canada, Europe, Japan) on semiconductor materials for IR sensors. He has more than 75 publications in referee journals. Prof. Gnatenko is a member of American Physical Society.
Refreshments will be served at 12:45 P.M.