Tungsten nitride
Tungsten nitride (W2N, WN, WN2) is an inorganic compound, a nitride of tungsten. It is a hard, solid, brown-colored ceramic material that is electrically conductive and decomposes in water.
It is used in microelectronics as a contact material, for conductive layers, and barrier layers between silicon and other metals, e.g. tungsten or copper. It is less commonly used than titanium nitride or tungsten films.