Surface-acoustic-wave device

A surface-acoustic-wave device which comprises:

• a laminate of a semiconducting material and a piezoelectric material;
• means for propagating a surface-acoustic-wave through said piezoelectric material;
• depletion layer control means provided locally at an interface of said semiconducting material and said piezoelectric material;
• a pumping electrode provided on a surface of said piezoelectric material;
• means for applying a DC bias voltage between said depletion layer control means and a location on said semiconductor material spaced from said depletion layer control means;
• and
• means for applying an AC pumping voltage between said pumping electrode and a location on said semiconductor material;
• whereby to cause a parametric interaction, between said surface-acoustic-wave propagated through said piezoelectric material and said pumping voltage, at a region or regions other than a region where said depletion layer control means is provided.

A surface-acoustic-wave device which comprises:

• a laminate of a semiconducting material and a piezoelectric material;
• means for propagating a surface-acoustic-wave through said piezoelectric material;
• depletion layer control means provided locally at an interface of said semiconducting material and said piezoelectric material;
• an insulating layer provided at said interface for surface passivation of said semiconducting material;
• and
• means for applying a DC bias voltage and an AC pumping voltage between said depletion layer control means and a location on said semiconducting material spaced from said depletion layer control means, to cause a parametric interaction, between said surface-acoustic-wave propagated through said piezoelectric material and said pumping voltage, at a region or regions other than a region where said depletion layer control means is provided.