Provided is a semiconductor device that comprises a metal gate having a low sheet resistance characteristic and a high diffusion barrier characteristic and a method of fabricating the metal gate of the semiconductor device. The fiber optic plate may comprise a plurality of parallel optical fibers, the terminal ends of the optical fibers combining to define a light input surface and an at least partially concave light output surface. The closed end of the slot includes a target area where the shrinking of the sleeve occurs. The post has a plurality of grooves formed thereon that help hold the post in the composite material of the shipping container. For example, a change in an intensity of an absorption maximum is measured and the ion concentration is determined accordingly.