FKA 190, Modelling and Fabrication of Micro/Nanodevices

Project title:

Fabrication and characterization of thin film ferroelectric varactors for applications in microwave microelectronics

Project description:

1. Literature studies of the field.

1.1. Phenomenology of ferroelectrics (materials with spontaneous electric polarization and field dependent dielectric constant).

1.2. Ferroelectric materials for voltage tuneable capacitors (varactors) suitable for applications in the microwave microelectronics.

1.3. Processing techniques for fabrication of micro/nanodevices (thin film deposition methods, lithography, material removing techniques).

1.4. Methods of characterization of the ferroelectrics (dielectric constant, polarization and loss tangent as functions of filed, frequency and temperature).

2. Fabrication of Ba_xSr_1-xTiO₃ thin film varactors on Pt/Au/Ti bottom electrode.

2.1. Deposition of the Pt/Au/Ti bottom electrode stack by electron-beam evaporation.

2.2. Patterning of the bottom electrode using photolithography and ion etching.

2.3. Growth of the Ba_xSr_1-xTiO₃ ferroelectric films by pulsed laser deposition (PLD).

2.4. Deposition and patterning of Pt/Au top electrode using photolithography, electron-beam evaporation and lift-off process.

3. Characterization of dielectric response of the Au/Pt/Ba_xSr_1-xTiO₃/Pt/Au/Ti vatactors.

3.1. Measurements of the varactor capacitance and loss tangent versus dc field at 1 MHz.

3.2. Measurements of the varactor capacitance and loss tangent versus frequency up to 25 GHz at different dc fields.

4. Writing of a scientific report.

Contact:
Andrei Vorobyev
<andrei.vorobyev -et- mc2.chalmers.se>

Microwave Electronics Laboratory

SE-412 96 Gothenburg, SWEDEN

Telephone: +46 (0) 31-772 8931

Fax: +46 (0) 31-164513