Modeling structural defect formation in cadmium telluride during electron irradiation

Yu Yu Loginov,A.V Mozzherin,N.N Paklin

doi:10.1088/1757-899x/467/1/012007

Abstract

We have conducted the formation of interstitial atoms and vacancies and made their clusters in the form of dislocation loops and voids in cadmium telluride under irradiation by electrons. We have calculated dependences of the radii of dislocation loops and voids depending on the irradiation time. We have compared the results of the simulation with the experimental data on the irradiation of CdTe in a transmission electron microscope as well.

Highlights

Modern technologies make it possible to produce semiconductor materials of very high quality with a low content of structural defects, but the structural defects that remain in them can make serious changes in the physico-chemical properties, and subsequently affect the operation of devices based on them
The results presented in fig. 1 show that in the center of the sample (z = 100 nm) interstitial atoms have greater mobility than vacancies
In the time interval 0.1-0.01 seconds the concentration of vacancies reaches a maximum which practically coincides with the minimum of the concentration of interstitial atoms, which is explained by the dynamics of the processes of generation and recombination of Frenkel pairs, as well as agglomeration of Frenkel pairs in the di-interstitials and divacancies, which are assumed to be the nuclei for the formation of the dislocation loops and vacancy voids

Summary

Introduction

Modern technologies make it possible to produce semiconductor materials of very high quality with a low content of structural defects, but the structural defects that remain in them can make serious changes in the physico-chemical properties, and subsequently affect the operation of devices based on them. Devices have to work in unfavorable conditions, for example, under the influence of radiation with different energies. Such an impact on semiconductor materials causes the transformation and development of a defective network. Influence of electrons with sub-threshold energies on the processes of structural transformations in semiconductors has been studied in [3,4,5,6,7] where it was reported about possibility of formation of point defects (vacancies and interstitials) in these materials under such irradiation. We conducted a simulation of the processes of defect formation in CdTe under electron irradiation. Based on the experimental studies reported in [7], it is known that in addition to the formation of interstitial clusters, vacancy clusters are observed in CdTe, so the model is modified taking into account the formation of vacancy clusters and the results of the simulation are compared with the previously obtained experimental data

Results and Discussion

K 1V cV2 K 1V

D V u 2 G

Conclusion