Characterized by a very fast growth of the electron population in vacuum of Radio-Frequency (RF) devices, the multipactor effect has been widely studied during the past decades. As it limits the transmitted RF power and may degrade RF devices, its understanding is primordial. Multipactor simulation tools give accurate results in the simplest cases, but are less accurate for advanced configurations: complex geometries, dielectric materials, presence of magnetic fields, etc. In such cases, an accurate modelling of the electron emission phenomena becomes essential. We extended a one-dimension electron emission (EE) model to three dimensions. The obtained model is compared to measured electron emission yields. The impact of this new model on the simulated multipactor threshold of parallel plane wave-guide is also investigated.