Back to results
US 11,770,112 B1Granted
MEMS resonator with co-located temperature sensor
AssigneeSiTime Corporation
InventorsCharles I. Grosjean, Ginel C. Hill, Paul M. Hagelin, Renata Melamud Berger, Aaron Partridge, Markus Lutz
Life of this patent
Estimating the term…
Abstract
A microelectromechanical system (MEMS) resonator includes a substrate having a substantially planar surface and a resonant member having sidewalls disposed in a nominally perpendicular orientation with respect to the planar surface. Impurity dopant is introduced via the sidewalls of the resonant member such that a non-uniform dopant concentration profile is established along axis extending between the sidewalls parallel to the substrate surface and exhibits a relative minimum concentration in a middle region of the axis.
Claims19
A semiconductor device comprising:
- a crystal silicon layer having first and second regions, the first region being doped in a manner not shared by the second region;
- a first microelectromechanical systems (MEMS) resonator having a first movable body formed from the first region;
- a second MEMS resonator having a second movable body formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- and
- wherein the first region has a dopant concentration of at least 1E19/cm3 and the second region of the first silicon layer has less than 1E18/cm3 of the dopant concentration.
3 more elements
A semiconductor device comprising:
- a crystal silicon layer having first and second regions, the first region being doped in a manner not shared by the second region;
- a first microelectromechanical systems (MEMS) resonator having a first movable body formed from the first region;
- a second MEMS resonator having a second movable body formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- and
- wherein the first movable body and the second movable body are each doped with the dopant at respective dopant concentrations that differ from each other by a factor of ten or more.
3 more elements
A semiconductor device comprising:
- a crystal silicon layer having first and second regions, the first region being doped in a manner not shared by the second region;
- a first microelectromechanical systems (MEMS) resonator having a first movable body formed from the first region;
- a second MEMS resonator having a second movable body formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- and
- wherein the first movable body has a dopant concentration that is at least 10E21 per cubic centimeter, wherein the second movable body has a dopant concentration that no more than 10E18 per cubic centimeter, and wherein each of the first movable body and the second movable body are doped with one of phosphorus, arsenic or antimony.
3 more elements
A semiconductor device comprising:
- a crystal silicon layer having first and second regions, the first region being doped in a manner not shared by the second region;
- a first microelectromechanical systems (MEMS) resonator having a first movable body formed from the first region;
- a second MEMS resonator having a second movable body formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- and
- wherein the first movable body is characterized by a first surface that is coplanar with the substrate, and a second surface that is not coplanar with the first surface, and wherein the first movable body is formed using a process that drives dopant into the first movable body via each of the first surface and the second surface, so as to establish a dopant profile that provides for declining dopant concentration as a function of distance within the first movable body from each of the first surface and the second surface.
3 more elements
A semiconductor device comprising:
- a crystal silicon layer having first and second regions, the first region having a dopant and the second region having a dopant, wherein the first region and the second region differ in at least one of a dopant type or a dopant concentration;
- a first microelectromechanical systems (MEMS) resonator having a first movable body formed from the first region;
- and
- a second MEMS resonator having a second movable body formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- and
- wherein the first movable body has a dopant, at the dopant concentration that is at least 10E21 per cubic centimeter and wherein the second movable body also has the dopant, at a dopant concentration that no more than 10E18 per cubic centimeter.
4 more elements
A method of fabricating a semiconductor device comprising:
- doping a crystal silicon layer having first and second regions in a manner such that the first region is doped in a manner not shared by the second region;
- forming a first microelectromechanical systems (MEMS) resonator having a first movable body, wherein the first movable body is formed from the first region;
- and
- forming a second MEMS resonator having a second movable body, wherein the second movable body is formed from the second region;
- wherein the first movable body and the second movable body have respective first-order temperature coefficients of frequency that differ from one another due, at least in part, to the doping of the first region relative to the second region;
- wherein forming the first MEMS resonator and forming the second MEMS resonator are performed such that the first region has a dopant concentration of at least 1E19/cm3 and the second region of the first silicon layer has less than 1E18/cm3 of the dopant concentration.
3 more elements
Dependencies are inferred from the claim text.