3 - Zinc selenide semiconductor: synthesis, properties and applications

Abstract

Zinc selenide (ZnSe) is an important II-VI group chalcogenide compound semiconductor. It is referred to as an II–VI semiconductor material because zinc (Zn) and selenium (Se) belong, respectively to II and VI groups of the periodic table. Like many other II–VI groups’ semiconductors, research on ZnSe synthesis and growth is gaining considerable attention due to the enhancement of some of its salient properties and applications. Generally, group II–VI semiconductors have a wide band gap of which the value of ZnSe is about 2.7eV at room temperature. Apart from the wide band gap, ZnSe has a large exciton binding energy (21meV), excellent electronic transport properties, high linear and nonlinear refractive indices, and good optical transparency over a wide range in the visible spectrum. These properties give the chalcogenide semiconductors unlimited applications in chemical analysis, biological bodies and diseases treatment, as well as physical, electrical, and mechanical devices. ZnSe band gap can be manipulated by controlling the particle sizes of the semiconductor material. It has been established that when the size of a nanoparticle is less than its exciton Bohr radius, it exhibits properties that are different from those of its bulk group material due to quantum confinement. This property is effectively utilized in electrical and optoelectronic technology and is replacing bulky devices with more effective nano-device materials. Reducing the size of nanoparticles leads to an increase in the energy band gap, and this can be achieved using different synthesis techniques and by doping with various foreign atoms. This chapter provides a comprehensive study of the state-of-the-art research activities that focus on the rational synthesis and growth techniques, novel properties, and unique applications of ZnSe nanostructures semiconductor.