PROJECT DETAILS
| Name: |
|
The use of rare earth elements to improve the preparation of InP- and PbI2- based semiconductor materials for detection of ionizing radiation |
| Co-principal investigator: |
|
Jaroslav Maixner, Ph.D. |
| From: |
|
2003-01-01 |
|
| To: |
|
2005-12-31 |
Detectors of ionizing radiation offer a broad spectrum of applications in
devices used in digital radio-logy, space research, X-ray and gamma spectroscopy.
The major theme of this project, which in some respects is a continuation of
previous work, is the employment of the specific properties of selected rare
earth (RE) elements in the preparation of high purity epitaxial layers of InP
(with undesired impurities concentration below 1015 cm-3 and mobilities on the
order of 1000 cm2/Vs) and structurally perfect bulk crystals of PbI2, both
destined for detection of ionizing radiation. The aim is to establish optimal
conditions for preparation of the detector structures with blocking electrodes.
Liquid phase epitaxy will be used for preparation of the InP layers, direct
synthesis and zonal purification for the PbI2 crystals. The blocking Schottky
electrodes will be formed by vacuum evaporation of suitable metals with possible
admixture of REs. Following diagnostics will be used: optical microscopy for
evaluating layer thickness and dislocation density, X-ray structural and
fluorescence analysis for identifying of lattice parameters and compositions,
low-temperature photoluminescence spectroscopy for studying optical properties.
The results of these methods will be correlated with those of the temperature
dependent Hall effect (measured by the van der Pauw procedure) and the C-V
measurements. Detector structures will be evaluated with respect to their
quantum efficiency for the alfa and gamma radiation, the carrier lifetimes and
temperature dependence of the spectral resolution.
