ZnS-Based ZnSTe:N/n-ZnS Light-Emitting Diodes

Abstract

ZnS1-xTex:N/n-ZnS diodes have been fabricated in an attempt to convert ZnS into p-type by Te incorporation and the resulting upward shift of the valence band maximum. The diodes exhibit clear rectification in the current–voltage characteristic and a peak of the electron-beam-induced current at the ZnS1-xTex:N/n-ZnS interface. Furthermore, a ZnS0.85Te0.15:N/n-ZnS diode exhibits blue-green electroluminescence due to self-activated emission in n-ZnS at 290 K under a forward current. These results suggest p-type conduction in ZnS1-xTex:N, and thus the LED operation of a ZnS-based pn-junction.

Molecular Beam Epitaxy and p-type Doping of ZnMgSTe Quaternary Alloys

“…ZnMgSTe layers were grown by a MBE system designed for sulfide growth [4,5] using metal Zn, Te (Osaka Asahi Metal), and Mg (Furuuchi Chemical), and elemental S (Furukawa Denshi) as source materials. In this system, ZnS is usually grown at a substrate temperature of 275 These growth conditions had been obtained in our previous study on ZnSTe ternary alloy growth [1,2], and were also used in this study. Composition of the grown films was evaluated by electron probe micro-analysis (EPMA).…”

“…Thus substituting a part of S in ZnS with Te causes VBM to move upward and seems to make p-type conversion easier. Actually, we have previously reported p-type conduction in ZnS 1−x Te x :N layers in the range of 0.1 < x < 0.3, and the operation of pn-junction light-emitting diodes [1,2]. With the addition of Te into ZnS, however, the bandgap decreases.…”

Surface topography, structural, optical and dc electrical behaviors of pristine and Co-doped ZnS thin films

“…[ 1 , 2 ]. Zinc sulfide (ZnS) is a compound semiconductor of ӀӀ-VӀ group which has drawn the attention of many researchers due to its excellent properties and numerous potential optoelectronic and spintronic applications for example flat panel displays [ 3 ], injection lasers [ 4 ], light emitting diodes [ 5 ], cathode ray tubes [ 6 ], thin film luminescence [ 7 ], buffer layer in the solar cell [ 8 ], etc. Nevertheless, to exploit some additional properties as well as enhance its physico-chemical properties, pure ZnS (PZS) thin film has been tailored by doping it with transition metals like Fe [ 9 ], Ni [ 10 ], Mn [ 11 ], Cu [ 12 ] and Co [ 13 ].…”

ZnSTe coherently grown onto GaP substrates by molecular beam epitaxy using ZnS buffer layers

“…It has also been known, however, that achieving p‐type conduction in ZnS is very difficult. We have previously reported p‐type conduction in ZnSTe:N layers in the range of , and the operation of pn‐junction light‐emitting diodes . The properties of the p‐type layers, however, were not satisfactory for practical applications, e.g., the typical resistivity of cm was not low enough and the photoluminescence intensity was very weak.…”