Tunable Semiconductor Device And Method For Making Tunable Semiconductor Device

A process for forming a semiconductor device, comprising:

• forming a first doped cladding layer on a semiconductor substrate, the first doped cladding layer having a top surface and a bottom surface, the bottom surface in contact with the semiconductor substrate;
• forming a first waveguide layer of essentially undoped piezoelectric material on the top surface of the first doped cladding layer, the first waveguide layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the first doped cladding layer;
• forming an active layer on the top surface of the first waveguide layer, the active layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the first waveguide layer;
• forming a second waveguide layer of essentially undoped piezoelectric material on the top surface of the active layer, the second waveguide layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the active layer;
• forming a second doped cladding layer on the top surface of the second waveguide layer, the second doped cladding layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the second waveguide layer;
• etching a first portion of the second doped cladding layer from the top surface of the second doped cladding layer to form a longitudinal structure and a longitudinal interdigitated transducer (IDT) from a second portion of the second doped cladding layer, the longitudinal structure being in a direction parallel to a longitudinal axis of the semiconductor device, the etching exposing a first surface portion of the second waveguide layer, and the IDT formed on the first surface portion of the second waveguide layer and extending longitudinally in a direction parallel to the longitudinal axis and being arranged to, in response to a signal from a signal generator, generate a surface acoustic wave (SAW) in a direction parallel to the longitudinal axis.

A tunable semiconductor device, comprising:

• a first doped cladding layer on a semiconductor substrate, the first doped cladding layer having a top surface and a bottom surface, the bottom surface in contact with the semiconductor substrate;
• a first waveguide layer of essentially undoped piezoelectric material on the top surface of the first doped cladding layer, the first waveguide layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the first doped cladding layer;
• an active layer on the top surface of the first waveguide layer, the active layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the first waveguide layer;
• a second waveguide layer of essentially undoped piezoelectric material on the top surface of the active layer, the second waveguide layer having a top surface and a bottom surface, the bottom surface in contact with the top surface of the active layer;
• a longitudinal structure parallel to a longitudinal axis of the semiconductor device on the top surface of the second waveguide layer comprising a doped semiconductor material;
• and
• a longitudinal interdigitated transducer (IDT) formed on the top surface of the second waveguide layer or on the bottom surface of the first waveguide layer, the IDT extending longitudinally in a direction parallel to the longitudinal axis and being arranged to, in response to a signal from a signal generator, generate a surface acoustic wave (SAW) in a direction parallel to the longitudinal axis.