MEMS resonator including main and sub movable beams, and exciting electrodes excited by alternating-current signal

A Micro-Electro-Mechanical System (MEMS) resonator, comprising:

• a main movable beam having first and second ends, the main movable beam being electrically insulated from a substrate and fixed to at least one end of the first and second ends;
• a plurality of sub movable beams including first, second, third, fourth, fifth and sixth sub movable beams, the sub movable beams being formed at respective predetermined intervals in a direction substantially perpendicular to a longitudinal direction of the main movable beam, to extend from the main movable beam and to project from both of first and second side surfaces of the main movable beam;
• a first exciting electrode provided at a position of the first side surface of the main movable beam to be close to the first and second sub movable beams which are located at a center of the longitudinal direction of the main movable beam;
• a fourth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the third sub movable beam which is located to be adjacent at a side of the first end to the second sub movable beam, and to be close to the fifth sub movable beam which is located to be adjacent at the side of the first end to the third sub movable beam;
• and
• a fifth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the fourth sub movable mean which is located to be adjacent at a side of the second end to the first sub movable beam, and to be close to the sixth sub movable beam which is located to be adjacent at the side of the second end to the fourth sub movable beam,
• wherein the first and second sub movable beams are excited by an electrostatic force to oscillate in an oscillation direction substantially perpendicular to the longitudinal direction of the main movable beam and parallel to a surface of the substrate by exciting the first exciting electrode using an alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a first-order mode thereof, and
• the third to sixth sub movable beams are excited by an electrostatic force to oscillate in the oscillation direction by exciting the fourth and fifth exciting electrodes using the alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a third-order mode thereof.

A Micro-Electro-Mechanical System (MEMS) oscillation circuit including a MEMS resonator,

• wherein the MEMS resonator comprises:
• a main movable beam having first and second ends, the main movable beam electrically insulated from a substrate and fixed to at least one end of the first and second ends;
• a plurality of sub movable beams including first, second, third and fourth sub movable beams, the sub movable beams formed at respective predetermined intervals in a direction substantially perpendicular to a longitudinal direction of the main movable beam, to extend from the main movable beam and to project from both of first and second side surfaces of the main movable beam;
• a first exciting electrode provided at a position of the first side surface of the main movable beam to be close to the first and second sub movable beams which are located at a center of the longitudinal direction of the main movable beam;
• a second exciting electrode provided at a position of the first side surface of the main movable beam to be close to the second sub movable beam and the third sub movable beam which is located to be adjacent at a side of the first end to the second sub movable beam;
• and
• a third exciting electrode provided at a position of the second side surface of the main movable beam to be close to the first sub movable beam and the fourth sub movable beam which is located to be adjacent at a side of the second end to the first sub movable beam,
• wherein the first and second sub movable beams are excited by an electrostatic force to oscillate in an oscillation direction substantially perpendicular to the longitudinal direction of the main movable beam and parallel to a surface of the substrate by exciting the first exciting electrode using an alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a second-order mode thereof,
• the first to fourth sub movable beams are excited by an electrostatic force to oscillate in the oscillation direction by exciting the second and third exciting electrodes using the alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a second-order mode thereof, and
• the MEMS oscillation circuit oscillates with an identical frequency to the resonant frequency of the MEMS resonator.

A Micro-Electro-Mechanical System (MEMS) oscillation circuit including a MEMS resonator,

• wherein the MEMS resonator comprises:
• a main movable beam having first and second ends, the main movable beam being electrically insulated from a substrate and fixed to at least one end of the first and second ends;
• a plurality of sub movable beams including first, second, third, fourth, fifth and sixth sub movable beams, the sub movable beams being formed at respective predetermined intervals in a direction substantially perpendicular to a longitudinal direction of the main movable beam, to extend from the main movable beam and to project from both first and second side surfaces of the main movable beam;
• a first exciting electrode provided at a position of the first side surface of the main movable beam to be close to the first and second sub movable beams which are located at a center of the longitudinal direction of the main movable beams;
• a fourth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the third sub movable beam which is located to be adjacent at a side of the first end to the second sub movable beam, and to be close to the fifth sub movable beam which is located to be adjacent at the side of the first end to the third sub movable beam;
• and
• a fifth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the fourth sub movable beam which is located to be adjacent at a side of the second end to the first sub movable beam, and to be close to the sixth sub movable beam which is located to be adjacent at the side of the second end to the fourth sub movable beam,
• wherein the first and second sub movable beams are excited by an electrostatic force to oscillate in an oscillation direction substantially perpendicular to the longitudinal direction of the main movable beam and parallel to a surface of the substrate by exciting the first exciting electrode using an alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a first-order mode thereof,
• the third to sixth sub movable beams are excited by an electrostatic force to oscillate in the oscillation direction by exciting the fourth and fifth exciting electrodes using the alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a third-order mode thereof, and
• the MEMS oscillation circuit oscillates with an identical frequency to the resonant frequency of the MEMS resonator.

A Micro-Electro-Mechanical System (MEMS) device including a MEMS resonator,

• wherein the MEMS resonator comprises:
• a main movable beam having first and second ends, the main movable being beam electrically insulated from a substrate and fixed to at least one end of the first and second ends;
• a plurality of sub movable beams including first, second, third and fourth sub movable beams, the sub movable beams being formed at respective predetermined intervals in a direction substantially perpendicular to a longitudinal direction of the main movable beam, to extend from the main movable beam and to project from both first and second side surfaces of the main movable beam;
• a first exciting electrode provided at a position of the first side surface of the main movable beam to be close to the first and second sub movable beams which are located at a center of the longitudinal direction of the main movable beams;
• a second exciting electrode provided at a position of the first side surface of the main movable beam to be close to the second sub movable beam and the third sub movable beam which is located to be adjacent at a side of the first end to the second sub movable beam;
• and
• a third exciting electrode provided at a position of the second side surface of the main movable beam to be close to the first sub movable beam and the fourth sub movable beam which is located to be adjacent at a side of the second end to the first sub movable beam,
• wherein the first and second sub movable beams are excited by an electrostatic force to oscillate in an oscillation direction substantially perpendicular to the longitudinal direction of the main movable beam and parallel to the surface of the substrate by exciting the first exciting electrode using an alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a first-order mode thereof,
• the first to fourth sub movable beams are excited by an electrostatic force to oscillate in the oscillation direction by exciting the second and third exciting electrodes using the alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a second-order mode thereof, and
• the MEMS oscillation circuit oscillates with an identical frequency to the resonant frequency of the MEMS resonator.

A Micro-Electro-Mechanical System (MEMS) device including a MEMS resonator,

• wherein the MEMS resonator comprises:
• a main movable beam having first and second ends, the main movable beam being electrically insulated from a substrate and fixed to at least one end of the first and second ends;
• a plurality of sub movable beams including first, second, third, fourth, fifth and sixth sub movable beams, the sub movable beams being formed at respective predetermined intervals in a direction substantially perpendicular to a longitudinal direction of the main movable beam, to extend from the main movable beam and to project from both first and second side surfaces of the main movable beam;
• a first exciting electrode provided at a position of the first side surface of the main movable beam to be close to the first and second sub movable beams which are located at a center of the longitudinal direction of the main movable beams;
• a fourth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the third sub movable beam which is located to be adjacent at a side of the first end to the second sub movable beam, and to be close to the fifth sub movable beam which is located to be adjacent at the side of the first end to the third sub movable beam;
• and
• a fifth exciting electrode provided at a position of the second side surface of the main movable beam to be close to the fourth sub movable beam which is located to be adjacent at a side of the second end to the first sub movable beam, and to be close to the sixth sub movable beam which is located to be adjacent at the side of the second end to the fourth sub moveable beam,
• wherein the first and second sub movable beams are excited by an electrostatic force to oscillate in an oscillation direction substantially perpendicular to the longitudinal direction of the main movable beam and parallel to the surface of the substrate by exciting the first exciting electrode using an alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a first-order mode thereof,
• the third to sixth sub movable beams are excited by an electrostatic force to oscillate in the oscillation direction by exciting the fourth and fifth exiting electrodes using the alternating-current signal, such that the MEMS resonator resonates with a resonant frequency of a third-order mode thereof, and
• the MEMS device utilizes a resonant state of the MEMS resonator.