A Schottky barrier is a metal-semiconductor junction that forms when a metal contacts a semiconductor, creating a potential energy barrier. This barrier is crucial for controlling the flow of electrons, allowing current to pass in one direction while blocking it in the opposite direction. The height of the barrier depends on the work function of the metal and the electron affinity of the semiconductor. In electronic devices, Schottky barriers are used in components like Schottky diodes, which are known for their fast switching speeds and low forward voltage drop. These properties make them ideal for applications in power electronics and radio frequency systems, enhancing efficiency and performance.