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Related Experiment Video

Updated: Jul 16, 2026

A Fabrication and Measurement Method for a Flexible Ferroelectric Element Based on Van Der Waals Heteroepitaxy

A Fabrication and Measurement Method for a Flexible Ferroelectric Element Based on Van Der Waals Heteroepitaxy

Published on: April 8, 2018

Tunable ferroelectric capacitor-based voltage-controlled oscillator.

Asad Jamil¹, Thottam S Kalkur, Nicholas Cramer

¹University of Colorado, Colorado Springs 80918, USA. ee.jamil@gmail.com

IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control

|March 3, 2007

Summary

This study presents a tunable ferroelectric capacitor using Barium Strontium Titanate (BST) for high-frequency circuits. The developed voltage-controlled oscillator (VCO) demonstrates a wide tuning range and low power consumption.

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Area of Science:

Materials Science
Electrical Engineering
Solid State Physics

Background:

Ferroelectric capacitors based on Ba(1-0.5)Sr0.5TiO3 (BST) are crucial for tunable, high-frequency applications.
Varactors are key components in voltage-controlled oscillators (VCOs) for frequency tuning.

Purpose of the Study:

To design and implement a VCO utilizing a tunable ferroelectric BST capacitor.
To evaluate the performance characteristics of the BST-based VCO for high-frequency circuit applications.

Main Methods:

Integration of discrete Radio Frequency (RF) bipolar junction transistors (BJTs) with a tunable ferroelectric capacitor.
Fabrication and testing of the complete VCO circuit.

Main Results:

The designed VCO achieved a tuning range from 205 MHz to 216.3 MHz.
The device exhibited a low power dissipation of 5.1 mW.
Measured phase noise levels were -90 dBc/Hz at 100 kHz and -140 dBc/Hz at 1 MHz offset.

Conclusions:

The BST ferroelectric capacitor is a viable component for tunable VCOs in high-frequency applications.
The implemented VCO demonstrates promising performance in terms of tuning range, power efficiency, and phase noise.