The transmitted phonon drag effect (TPDE) predicted by Shockley (1) has been studied on n-p-n-junctions of germanium and silicon. In this paper, the TPDE is considered a s applied to epitaxial n-i-n-structures (n being a semiconductor film of electron type and i being a semi-insulating layer).If an electric field E is applied to a film of n-type (emitter), a phonon drag caused by electrons appears in this film. These phonons (we call them relevant) penetrate the i-layer (propagating layer) scattering on phonons, impurities, a t the film-substrate boundary, e t c . , and having reached the bottom film (receiver) they transmit their momentum to the electrons. A s a result of this, a direct movement of the electrons (electron drag caused by phonons) and, therefore, the electric field E of polarity opposite to E occurs.

In honour of Prof. Dr. Dr. h. c. P. GB~JCH'S 70th birthday A thcory of transmitted phonon drag effect (TPDE) in a sandwich n-i-n-structure (n is an electron layer and i a semiinsulating one of the semiconductor) is considered. The solution is performed on the basis of a kinetic equation system for electrons and phonons. The calculated results enable a good qualitative description of the main dependences of TPDE in GaAs. An analysis of expcriniental results shows that the transmitted phonons are dragged by elect.rons mainly through the deformation potential. The transmitted pholions are represented by long-wavelength acoustic ones the relaxat.ion of which is described by Herring's theory, the constant of the phonon-phonon interaction B is equal to 2 X