MEMS resonator with beam segments having predefined angular offset to each other and to resonator silicon crystal orientation

An integrated circuit package comprising:

• a die;
• a micromachined resonator on the die, the micromachined resonator having
• a first structure formed from a silicon wafer having a crystallographic orientation, the first structure having a length extending along a first axis, the first axis having a predetermined angular offset from the crystallographic orientation, the first structure to move in resonant motion,
• a second structure also formed from the silicon wafer, the second structure having a length extending along a second axis, the second axis having a predetermined angular offset from each of the first axis and the crystallographic orientation, the second structure to move in resonant motion,
• wherein the predetermined angular offset of the second axis from the crystallographic orientation is less than forty-five degrees and is the negative of the predetermined angular offset of the first axis from the crystallographic orientation, and
• wherein the first structure and the second structures are structurally coupled, wherein a resonant frequency of the micromachined resonator is dependent on the first structure and the second structure, and wherein the first structure and the second structure each include an impurity dopant having concentration which is greater than 1019 cm−3;
• and
• at least one electrode to sense the resonant frequency of the micromachined resonator;
• wherein the die has at least one electrical contact to provide an output signal dependent on the sensed resonant frequency of the micromachined resonator.

An integrated circuit package comprising:

• a die;
• a micromachined resonator on the die, the micromachined resonator having
• first, second, third and fourth structures formed from a silicon wafer having a crystallographic orientation, the first structure having a length extending along a first axis, the first axis having a predetermined angular offset from the crystallographic orientation, the second structure having a length extending along a second axis, the second axis having a predetermined angular offset from each of the first axis and the crystallographic orientation, each of the first, second, third and fourth structures to move in resonant motion,
• wherein the predetermined angular offset of the second axis from the crystallographic orientation is less than forty-five degrees and is the negative of the predetermined angular offset of the first axis from the crystallographic orientation,
• wherein the third structure has a length extending in a direction parallel to the first axis,
• wherein the fourth structure has a length extending in a direction parallel to the second axis;
• wherein the first, second, third and fourth structures are structurally coupled, wherein a resonant frequency of the micromachined resonator is dependent on the first second, third and fourth structures, and wherein the first, second, third and fourth structures each include an impurity dopant having concentration which is greater than 1019 cm−3;
• and
• at least one electrode to sense the resonant frequency of the micromachined resonator;
• wherein the die has at least one electrical contact to provide an output signal dependent on the sensed resonant frequency of the micromachined resonator.