[en] In the framework of our research program on the halo nuclei we have performed a complete kinematical study on the ¹⁴Be breakup on different targets. This nucleus can be described as a ¹²Be core, detected by a position sensitive assembly of Si-CsI detectors, and two neutrons, constituents of the halo, detected by DEMON. The neutron detection of the focused neutrons along the beam axis, implies a DEMON configuration of high efficiency and maximal granularity at small angles. To obtain this, the modules must be relatively close to each other, but this enhances the diaphony effect (the scattering of a single neutron from several models). The MENATE and GIANT codes were applied to find the configurations minimizing the diaphony, on one hand, and a filter for identification of false events, on the other hand. Among the 12 studied configurations the following three were the most significant: 1. compact, in which the module centers are separated by 25 cm; 2. columns, in which modules are regrouped in columns, the distance between module centers being 35 cm; 3. zigzag, in which the lines of the columns is in zigzag in order to obtain four walls between 3.5 and 6.5 m with a distance between the modules in the wall of at least 40 cm. Results of the simulations for a neutron pair distribution with a width of 50 MeV/c and a beam energy of 30 MeV/N are presented. To characterize the diaphony, a filter was developed to take into account different kinematical characteristics between the true events (pairs of neutrons) and false events (diaphony). It was found that the compact configuration presents a high efficiency but a diaphony rate still important and in addition the original distribution is highly deformed. Instead, the column configuration preserves the profile of the original distribution with a lower diaphony rate but with a efficiency reduced by about 40%. Finally, the zigzag configuration which combines the advantages of the two configurations, i.e. the high efficiency, a low diaphony and the original profile of the distribution, has been adopted