Oue of the most important challenges to the electronks índustry i5 the production of a fiat panel display which fulfills the requirements of high quaiíty irnage 1 large area t low power and low cost. Field Emission Display (FED) is the technoJogy in best oonditions to face these l'cquirements, However, the short lifetime and low reiiability of FED prototypes based ou metaUíc ernitters are hindering this technology to get iuto the market. In this work we investigate two different approaches that could represent a solution for these problems: improvement of the vacuum cha racterístics inside the emission cbamber and use of carbon nanotubes as emitters. With respect to the improvement af vacumn ín a FED, this work proposes a new type of emitter based on a porous díamond membrane. Theoretical calcu)ations referent to the vacuum properties and referent to ele<::trostatic field enhancement fador are presented. A new mode! is proposed to determine the superior limit for the eletrostatic field enhancement fador in a porous emitter. With respect to tbe experimental part of this work, we show that diamond porous membranes indeed emit eledrons, according to the original proposition. The emission performance of these membranes is oompared to the performance of flat metalic emitters: coated or not with diamond-like carbon. Images of emissiôn spôts in pores and a study of the long term membrane emission stabiHty are presented. \Vith respect to carbon nanotubes, thls work presents a new treatment process! under plasma are) that re sulted in emission improvement. A study 011 emission stability of nanotubes ia a150 presented) and systematical emission decay is reporte