The traveling wave potential wells, associated with a surface acoustic wave (SAW) generated in a multilayer epitaxial GaAs structure, are used to transport electrons at the velocity of sound in the buried channel formed by a Schottky-N-P layer configuration. A monolithic delay line based on the SAW transport concept is constructed and the time domain response of the delay line is presented. The SAW charge transport concept in GaAs is expected to be useful for the implementation of high-speed monolithic signal processors.

A simple noniterative method using an orthonormal basis for expressing field distributions has been developed for obtaining surface-wave solutions in piezoelectric crystals. Velocity and field distributions are obtained for YZ LiNbO3 that agree with earlier works. The boundary conditions are incorporated in a manner that is easily adapted to layered structures. Dispersion curves are obtained for surface waves in LiTaO3 with a SiO2 layer at the surface; the results are in good agreement with those published earlier.

The problem of surface-wave reflection at thin-strip overlays occurs frequently in signalprocessing devices. Grooved array reflectors employ strip overlays of the same material as the substrate, while metallic transducers incorporate strips of a material different from the substrate. A simple model for calculating the reflection coefficient of thin overlays is described, based on the normal-mode analysis developed by Auld. Calculated values are in close agreement with reported experimental values for grooves in ST-X quartz and Y -Z lithium niobate, and for aluminum on ST-X quartz.

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A theory is developed which describes the fundamental charge transfer characteristics of basic buried channel GaAs structures which are illuminated by large amplitude surface acoustic waves. Several approximations which simplify the analysis are shown to be valid in this channel structure. The theoretical approach treats carrier diffusion as a perturbation on the diffusionless two-dimensional electrostatic problem. Simple closed form expressions are obtained for packet charge density and boundary shape in terms of the channel parameters. It is shown that four sets of numerically generated and normalized curves are sufficient for the determination of the transport characteristics of a wide range of channel potential geometries. The dependence of diffusion induced transfer inefficiency on charge load and wave potential is investigated. The results indicate that high speed acoustic charge transport is capable of supporting typical buried channel charge loads at very high transfer efficiency.