There have been researched how the consistently connected potential barriers influence on physical processes running in p–n-heterojunction on an example of one- and multibarrier structures. It is shown, that updating of the heterojunction by creation of the consistently connected barrier to a substrate and to heterolayer result in convertion of a passive parasitic part of a substrate to the active category and its modulation from the two-parties. The third barrier generated to heterolayer excludes the injection of carriers to the base area and essentially reduces capacity of structure