6 - Functional Thin Films

Abstract

In this chapter, a sputtering deposition and applications of typical functional thin films are described. Variety of functional materials is developed in a form of bulk ceramics and/or bulk single crystals. Thin films of these functional materials are essential for present and future electronic components and/or MEMS. However, a reliable fabrication process of the functional thin films in production has not been fully established yet. Examples of deposition process for functional materials are described in this chapter in relation to their applications based on author’s academic and/or industrial research since 1960s. These experimental data include a key process condition that will be helpful for the development of new functional thin films for present and future electronic devices. Several examples of functional thin films including ZnO, perovskite ferroelectric materials, carbide, nitride, silicide, and organic materials are described in relation to their applications. Among these materials ZnO crystals are known as piezoelectric materials with a large electromechanical coupling factor and are used for making ultrasonic transducers in high-frequency regions, blue laser, and/or transparent conducting thin films for solar cells. In this chapter, ZnO transparent thin films are discussed by an expert in this field. In this chapter, several unique sputtered thin film materials and/or processing are described including room temperature diamond crystals, room temperature doping of foreign atoms in low pressure magnetron, and/or direct sputtering of organic thin films.