This paper is a revue of our experimental data regarding field emitter array fabrication, various field emission materials and application in pressure sensors domain. Silicon emitter's arrays of different sizes and geometrical shapes were realised using micromachining technologies. Some important aspects as control in etch rate, emitter profile, selectivity and surface morphology were investigated, The emitter surface was modified or was covered by different materials in order to improve the emission properties. The most usual materials investigated for FED applications were: Si, diamond-like carbon layers, silicon carbide, and porous silicon. The main application which is present in our attention is the field emission pressure sensor.