Photoluminescence study of zinc(1-x)manganese(x)sulfur
[Thesis]
M. A. Moreno
F. D. Medina
Florida Atlantic University
1989
132
M.S.
Florida Atlantic University
1989
Zn1-xMnxS is a ternary semiconductor compound which belongs to the family of diluted magnetic semiconductors (DMS). It has two crystalline phases: cubic for x usd\lequsd 0.10, and hexagonal for 0.10 usd\lequsd x usd\lequsd 0.50. Its energy gap is temperature and x dependent. The gap, ranging from 3.7 to 3.8 eV, is the largest of the DMS. These properties allow studies of the energy levels of the Mn ions in ZnS and their internal or ion-to-band transitions, by using photoluminescence. Samples with x = 0.01-0.50 were excited with the 5145A line of an Ar laser. The spectra, taken at temperatures between 10 and 300K, showed three bands: a band peaking at 2.12 eV was related to the T1\ \to\ \sp6A internal transition; a band peaking at 1.95-2.10 eV (depending on T) was related to the T1\ \to\ \Gamma\sb ion-to-band transition; the origin of the third band, peaking at 1.65 eV, was discussed. A partial fourth band in the IR region was detected. The position of the A state with respect to the valence band was established.