illustrated in fig8 where three frames 14 16 30 are nested the vent of a frame being positioned opposite to the vent of the closest external frame thus the more frames there are the longer the bypass duct and the more time is available between the time when the filling material is deposited and the time when the cap is installed which is advantageous when more than some hundred circuits are hybridized indeed when a number of circuits has to be hybridized a time u201c tpd u201d elapses between the deposition of glue on the first chip and the deposition of glue on the last chip it should thus be ensured that the glue remains in the bypass duct and does not reach the cavity for the last chip as well as for the first one the latter u201c seeing u201d the glue advance for a longer time tpd similarly as illustrated in fig9 a single spiral wound wall 34 may be used to form the external frame and the bypass duct which enables to form a long bypass duct on a minimum surface area an application of a method according to the present invention to the collective manufacturing of mems circuits has been described of course the present invention applies to other types of circuits requiring to be enclosed in tight cavities for.