Accession Number : AD0709707

Title :   SOME SWITCHING CHARACTERISTICS OF CALCIUM BORATE GLASSES CONTAINING IRON.

Descriptive Note : Progress rept. no. 13, 1 Feb-30 Apr 70,

Corporate Author : AMERICAN UNIV CAIRO (EGYPT) DEPT OF MATERIALS ENGINEERING AND PHYSICAL SCIENCES

Personal Author(s) : Bishay,Adli ; Omar,M. H. ; El Hamamsy,M.

Report Date : 08 JUN 1970

Pagination or Media Count : 82

Abstract : A series of calcium borate glasses containing from about 10 to 30 mole% Fe203 was investigated. Electrical switching phenomena were observed in all the samples. The threshold voltage decreased by a factor of about one hundred as the concentration of iron increased beyond 20 mole% Fe203. On the other hand, the threshold voltage increased with sample thickness and decreasing temperature for the same iron content. Negative resistance was sometimes observed before the samples were converted from the OFF to the ON state. A memory effect was also observed upon exceeding a certain threshold current. The switching phenomena (whether negative resistance or switching with memory effects) in the calcium borate glasses containing iron can be tentatively explained on the basis of a simple theory of Joule microheating. (Author)

Descriptors :   (*SOLID SOLUTIONS, ELECTRICAL CONDUCTIVITY), (*SEMICONDUCTOR DEVICES, SWITCHING CIRCUITS), NEGATIVE RESISTANCE CIRCUITS, BAND THEORY OF SOLIDS, GLASS, IRON OXIDES, CALCIUM COMPOUNDS, BORATES, EGYPT

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE