Thin film voltage-tuned semiconductor bulk acoustic resonator (SBAR)

A thin film voltage-tuned semiconductor bulk acoustic resonator (SBAR) comprising:

• a semiconductor substrate having a via hole formed therein;
• a first electrode positioned over the via hole adjacent to the semiconductor substrate;
• at least one piezoelectric film positioned over the via hole adjacent to the first electrode;
• a second electrode adjacent the piezoelectric film;
• and
• variable voltage source means for applying a DC bias voltage to the first electrode and the second electrode to create an electric field between the first electrode and the second electrode within the piezoelectric film, said electric field operable to cause the piezoelectric film to resonate at a frequency other than the piezoelectric film resonant frequency when unbiased, wherein the DC bias voltage is adjustable between -30 volts to +30 volts to substantially vary the electric field to adjust the piezoelectric film to resonate at a plurality of frequencies having a tuning range of at least 1,000 parts per million (ppm) and highly linear characteristics.

A method of creating a plurality of voltage-tuned resonant frequencies, said method comprising the steps of:

• providing a semiconductor substrate having a via hole formed in the semiconductor substrate;
• positioning a first electrode over the via hole adjacent to the semiconductor substrate;
• positioning a piezoelectric film over the via hole adjacent to the first electrode;
• positioning a second electrode adjacent the piezoelectric film;
• applying a DC bias voltage to the first electrode and the second electrode to generate an electric field between the first electrode and the second electrode within the piezoelectric film, wherein said electric field is operable to cause the piezoelectric film to resonate at a frequency other than the piezoelectric film unbiased resonate frequency;
• and
• varying the DC bias voltage to substantially vary the electric field thereby adjusting the piezoelectric film to resonate at a plurality of frequencies with highly linear characteristics.