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 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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.