This chapter provides an overview of the characteristic of development and evolution of solid-state electronics industry. The shrink and the efforts of the industry to abide by Moore's law are driven by two factors-the improved performance due to increased speed and functions per unit area, and the lower cost per bit. Materials play a crucial role in microelectronics revolution and evolution as the ability to produce devices with high performance, high reliability, and affordable price depends on the materials chosen. The core of a microelectronic device is the semiconducting material. Current microelectronic devices are based on silicon (Si), especially the optoelectronic devices, which utilize mainly III-V semiconductors such as GaAs, InP, and GaN. The first group consists of dielectric films that play an active role in device operation, mainly for the storage of charge. The second group consists of dielectric films that are needed during device processing. The third group of dielectric films utilized in microelectronic devices consists of insulating layers. New materials have recently been introduced in microelectronic devices in the semiconducting and metallic parts of the device.