Patent ID: 11897757
Assignee: SITIME CORPORATION
Field: Basic communication processes (Electrical engineering)
Classification: CPC B  H | IPC B  H

Claim 19:
20. 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.