The Correlation Between Dislocations and Vacancy Defects Using Positron Annihilation Spectroscopy

An analysis program for positron annihilation lifetime spectra is only applicable to isolated defects,but is of no use in the presence of defective correlations.Such limitations have long caused problems for positron researchers in their studies of complicated defective systems.In order to solve this problem,we aim to take a semiconductor material,for example,to achieve a credible average lifetime of single crystal silicon under plastic deformation at different temperatures using positron life time spectroscopy.By establishing reasonable positron trapping models with defective correlations and sorting out four lifetime components with multiple parameters,as well as their respective intensities,information is obtained on the positron trapping centers,such as the positron trapping rates of defects,the density of the dislocation lines and correlation between the dislocation lines,and the vacancy defects,by fitting with the average lifetime with the aid of Matlab software.These results give strong grounds for the existence of dislocation-vacancy correlation in plastically deformed silicon,and lay a theoretical foundation for the analysis of positron lifetime spectra when the positron trapping model involves dislocation-related defects.