Showing papers by "Peter H. Beton published in 1988"
TL;DR: In this paper, graded composition AlGaAs layers are used to generate a non-equilibrium distribution of electrons, in order to spatially control the transfer of electrons from the Γ to L valleys.
Abstract: The use of semiconductor multilayers for hot electron injection and intervalley transfer have recently been demonstrated. In this study graded composition AlGaAs layers are used to generate a non-equilibrium distribution of electrons, in order to spatially control the transfer of electrons from the Γ to L valleys. The consequent growth of charge and field instabilities has been investigated both experimentally and by Monte-Carlo simulation. Particular emphasis has been placed on the exploitation of these hot electrons in transferred electron devices. Gunn diodes consisting of such graded gap layers, and transit regions of 1 μm have been fabricated by molecular beam epitaxy. They have been observed to oscillate at a frequency of 95 GHz. Experimental results on these structures, together with their Monte-Carlo simulations, are discussed.
30 citations
TL;DR: Very thin n/sup +/ layers of semiconductor (spike doping) may be used to control the potential difference between microelectronic components while not significantly modifying any nonequilibrium distributions of electron energy or momentum across their extent as discussed by the authors.
Abstract: Very thin n/sup +/ layers of semiconductor (spike doping) may be used to control the potential difference between microelectronic components while not significantly modifying any nonequilibrium distributions of electron energy or momentum across their extent. The authors demonstrate this general principle with the example of a hot electron injection Gunn diode. >
12 citations
TL;DR: The results of Monte-Carlo simulations of hot electron spectrometers are presented in this paper, where the phonons and plasmons are coupled and treated within the same formalism as electron-electron scattering.
Abstract: The results of Monte-Carlo simulations of hot electron spectrometers are presented. We are able to account for the gross features observed experimentally including the effects of an applied magnetic field. Scattering rates in the highly doped drift region of the spectrometer are calculated from the dielectric function for the dynamically screened polar optic phonon. Using this method the phonons and plasmons are coupled and are treated within the same formalism as electron-electron scattering. It is shown that electrons scattered out of the drift region by the incident hot electrons make a significant contribution to the low energy part of the spectra. The existence of ‘echo peaks’ corresponding to electrons scattered twice or more is not predicted if the dispersion of the plasmon mode is included in the simulation. We calculate an inelastic scattering length of 40 nm and a scattering angle of 0.4 radians. A comparison of the calculated and observed effects of a magnetic field on the ballistic part of the spectrum yields a degree of collimation for the injected electrons.
8 citations
TL;DR: In this paper, a self-consistent Monte Carlo simulation on repeated velocity overshoot structures was performed to assess the potential of such structures to enhance the average drift velocity of electrons.
Abstract: We have performed self-consistent Monte Carlo simulations on repeated velocity overshoot structures. From our calculations, we may assess the potential of such structures to enhance the average drift velocity of electrons. We find that there is no enhancement for uniformly doped structures. For spike-doped structures there is a small enhancement, but this is gained at the expense of a drop in current density. In both structures the velocity enhancement is limited by intervalley scattering.
Patent•
01 Apr 1988
TL;DR: In this paper, the authors present an extension of the FABRICATION D'OSCILLATEURS A SEMI-CONDUCTEURS (FABRICATING DOSCillateURs A EFFET GUNN).
Abstract: L'INVENTION CONCERNE UN OSCILLATEUR A EFFET GUNN. ELLE SE RAPPORTE A UN CORPS D'UN MATERIAU SEMI-CONDUCTEUR DANS LEQUEL DES ELECTRONS SONT INJECTES D'UNE PREMIERE REGION 1 A UNE AUTRE REGION 5 PAR L'INTERMEDIAIRE D'UNE TRES MINCE REGION 3. CETTE DERNIERE A UNE EPAISSEUR INFERIEURE AU LIBRE PARCOURS MOYEN DES ELECTRONS, PAR EXEMPLE DE L'ORDRE DE 10 NM, SI BIEN QUE LES ELECTRONS SONT TRANSFERES DE LA REGION D'INJECTION VERS L'AUTRE REGION DANS LAQUELLE DES PAQUETS D'ELECTRONS SE FORMENT. APPLICATION A LA FABRICATION D'OSCILLATEURS A SEMI-CONDUCTEURS.