Measuring system for investigating semiconductor material using SAW - has piezoelectric delay line with gate for coupling adjustable pulsating DC field and interdigitated input=output transducers and two-channel detector for evaluating orthogonal components.

摘要

The system includes a piezoelectric component as a delay line, for the detecting surface wave, a circuit with an HF generator for the prodn. of this wave, a circuit for producing electric fields and a circuit for analysing the detecting surface wave. The delay line (16) has a gate electrode (29) for the connection of an adjustable, pulsable electrical DC field and an input and an output interdigitated transducers (161,163). Superimposed coupling in of a second transfer surface wave and for selective decoupling of the detecting surface wave are provided. The circuit for the analysing of the detecting surface wave is constructed as two channels for the evaluation of orthogonal signal components in real time. ADVANTAGE - Determines nature and manner of properties such as alterations of distribution of moving and fixed charge carriers in semiconductor material. Sudden responses observed as time transients can be read with high sensitivity and resolution. Provides data concerning charge storage and transport and other parameters.