The multipactor phenomenon is characterized by a very fast growth of the electronic population in Radio-Frequency (RF) devices under vacuum. As this effect limits the transmissible RF power and can harm RF systems, it has been widely studied during the last decades. Due to the high cost of experimental tests, simulation tools are heavily used to predict the threshold of multipactor growth. However, their reliability is limited for complex configurations, e.g. when dielectrics or magnetic fields are present. A crucial element of these multipactor simulations is the secondary-emission model. Dionne model is able to model both metals and dielectrics secondary emission but is one-dimension only. As the three-dimensional aspect is essential for complex configurations, the Dionne model is extended do three-dimensions. Measurements of the total electron emission yield have been carried out at the ONERA and shows a good agreement for low-impact energy and low-impact angle electrons, which is relevant in multipactor simulations.