Reverse Biased Electroluminescence in Alloyed ZnTe Diodes

Abstract

Reverse biased electroluminescence is observed in In-alloyed ZnTe (P-doped, ∼1018/cm3) diode at liq. N2 temperature. There are two characteristic emission bands in the luminescence spectrum. One is a green band, about 60 Å in width, centred at 5400 Å. The other is a red band and extends from about 5800 Å to 7000 Å. The former is attributed to P-centre emission, while the latter to In-centre emission. The weight of the two emission bands change with the alloying temperature, higher temperature favouring the latter. The emission mechanism is explained as a breakdown in the metal-semi=insulator-semiconductor (p-type) structure.

Electroluminescence and Other Optical and Electrical Characteristics of p-n Junctions in Zinc Sulfide

“…The luminescence of Si diodes under breakdown conditions was first reported by Newman in 1955 [29]. Similar breakdown luminescence was later reported for Ge [30], GaP [31], GaAs [32], SiC [33], ZnTe [23], and ZnSe [20].…”

“…The relative intensities of these two bands vary with temperature: at higher temperatures, the red band predominates; at lower temperatures, the green band is stronger. A comparison with the photoluminescence spectrum [23] demonstrates that the green band is due to the recombination of free electrons or of electrons captured by shallow traps with holes located at the acceptor levels of phosphorus. The red band may be associated with indium impurities and may be attributed to the recombination of electrons localized at deep donor levels with holes from the valence band or holes trapped at shallow acceptor levels.…”