Accession Number : AD0701694

Title :   FINAL REPORT ON CONTRACT NONR-562(27),

Corporate Author : BROWN UNIV PROVIDENCE R I METALS RESEARCH LAB

Personal Author(s) : Elbaum,C.

Report Date : JAN 1970

Pagination or Media Count : 9

Abstract : A number of experimental and theoretical projects were carried out; for example, it was demonstrated that condensation of vacancies constitutes an important mechanism for forming dislocations following crystal growth. The electric charge associated with dislocations in ionic crystals was determined directly for the first time; It was shown theoretically that electronic energy bands are associated with dislocations in wide-band-gap compound semiconductors and certain characteristics of these bands were predicted; In a study of the drag on moving dislocations in metals it was demonstrated that the interaction due to conduction electrons is temperature independent and is dominant only at very low temperatures. Further investigations of these problems are in progress.

Descriptors :   (*DISLOCATIONS, SOURCES), CRYSTAL GROWTH, GRAIN BOUNDARIES, SINGLE CRYSTALS, BAND THEORY OF SOLIDS, SEMICONDUCTORS, CADMIUM SULFIDES, GALLIUM

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE