▎ 摘　　要

A planar heterostructure composed of two graphene films between which a narrow-gap semiconductor ribbon is inserted was studied. It was shown that the Klein paradox is absent when conical points of the graphene Brillouin zone are in the band gap of a narrow-gap semiconductor. There is an energy range dependent on the angle of incidence, in which an above-barrier decaying solution can exist. Thereby, such a heterostructure is a filter transmitting particles in a certain range of angles of incidence on the potential barrier. The applicability of such a heterostructure as a gate is discussed.