Transparent Conducting Oxides

This chapter elaborates on a distinct class of semiconductor materials known as transparent conducting oxides (TCO). These materials have novel characteristics because they exhibit an unusual combination of two contemporary properties: high optical transparency and high electrical conductivity. The unique optoelectronic properties of these materials depend on different parameters, which are discussed in detail in the chapter. For the optical properties, contributing factors, such as optical gap, hybridization of the orbitals, defects, and doping, are discussed in detail. On a similar platform, the effective masses and electron distribution laws were discussed to justify the electrical properties of the TCOs. Furthermore, different types of TCO materials are discussed in this section. The materials are elaborated with their structures, which are responsible for imparting unique properties to a specific material. Transparent conducting oxides form the backbone of modern technology because of their unique combination of transparency and conductivity. The chapter also describes different routes for depositing transparent conducting oxides in the form of nanostructures, such as thin films and nanoparticles. Deposition techniques play a significant role in imparting specific properties to deposited nanostructures. Two types of deposition techniques, i.e., physical deposition techniques and chemical deposition techniques, along with their specific requirements, are explored in this chapter. Among the chemical deposition techniques, this chapter lays special emphasis on the sol–gel-based spin-coating technique because it is inexpensive and easy to handle. Furthermore, the importance of transparent conducting oxides from an application perspective is discussed. Application of transparent conducting oxides in photovoltaics, display devices, sensors and multifunctional coatings are also elaborated in detail.