The fast growth of semiconductor and electronics industry within the last couple of decades have revolutionized our daily life. Nowadays, opto-electronic devices such as smart phones, tablets and touch screens are the necessary ingredients of modern life. One of the major components of smart phones, touch screen and tablets are transparent conductors (TC), materials possessing great electrical conductivity and high optical transparency. TCs are also widely used in solar cells and OLED as electrode.
Indium Tin Oxide (ITO) is the primarily choice of manufacturer as TC compound in various devices because of its good electrical conductivity and high optical transparency. However, ITO price is growing because the limited resources and high cost of Indium (as a rare Earth element) as well as large market demand. Therefore, variety of methods and strategies have been developed in order to propose an alternative TC for ITO. Carbon nanotubes, graphene, metals nanowires, structured thin films, metal-dielectric nanocomposite as well as other transparent conductive oxides (TCO) are the major developed TCs so far. Among the variety of systems, TCOs are the most promising and they have been even successfully implemented in some devices. In particular, aluminum-doped zinc-oxide (AZO) is a rather mature system which have been integrated in thin film solar cells. AZOs are generally fabricated with chemical methods which makes the production price very low. In addition, all the elements of AZO are abundant in nature and therefore do not have the problem of limited resources like Indium. The trends to develop new TCs are in progress to find even cheaper alternative than that of AZO while being high efficient.