# US 9,039,280 B2 · Highly-reliable micro-electromechanical system temperature sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,039,280 B2 - Document ID: US9039280B2 - Status: Granted - Kind: B2 - Application number: 13/747,433 - Filed: 2013-01-22 - Published: 2013-08-08 - Granted: 2015-05-26 - Earliest claimed: 2012-01-20 - Assignees: Purdue Research Foundation - Applicants: Purdue Research Foundation - Inventors: Dimitrios Peroulis; Andrew S Kovacs; David Joseph Koester; Farshid Sadeghi; Sean M Scott; Douglas Edward Adams - Web page: https://patentgrep.com/patent/US9039280B2 ## CPC - G01K 7/34: using capacitative elements (capacitors per se H01G) - G01K 1/024: for remote indication - G01K 13/08: in rotary movement - H10W 72/536: {the connected ends being ball-shaped} - G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A micro-electromechanical system-type (MEMS) sensor arrangement for wirelessly measuring temperatures is disclosed. The MEMS sensor arrangement includes a multimorph sensor, a sensor coil coupled to the multimorph sensor, and a readout coil configured to be magnetically coupled to the sensor coil to i) energize the sensor coil, and ii) provide a readout of the natural frequency of the multimorph sensor, the sensor coil and the readout coil. ## Claims ### Claim 1 A micro-electromechanical system-type (MEMS) wireless temperature measurement system, comprising: a MEMS sensor arrangement, including: a multimorph sensor, a sensor coil coupled to the multimorph sensor, and a readout coil configured to be magnetically coupled to the sensor coil to i) energize the sensor coil, and ii) provide a readout of a natural frequency of the multimorph sensor, the sensor coil and the readout coil; an energizing circuit configured to energize the readout coil; and a readout circuit configured to measure the natural frequency. ### Claim 2 (depends on 1) The MEMS wireless temperature measurement system of claim 1, wherein the multimorph sensor comprises: an electrically conducting substrate with a well area provided thereon; a plurality of electrically insulating beams disposed over the well area of the electrically conducting substrate and fixed to the electrically conducting substrate at a first end and moveable with respect to the well area of the electrically conducting substrate at a second and opposite end of each of the electrically insulating beams; and a plurality of electrically conducting beams, each electrically conducting beam attached to and positioned over a corresponding electrically insulating beam. ### Claim 3 (depends on 2) The MEMS wireless temperature measurement system of claim 2, wherein each of the plurality of electrically conducting beams having thermal expansion characteristics substantially different than each corresponding electrically insulating beam. ### Claim 4 (depends on 3) The MEMS wireless temperature measurement system of claim 3, wherein the second end of each combination of the electrically conducting beam and the corresponding electrically insulating beam is positioned at a first distance with respect to the electrically conducting substrate. ### Claim 5 (depends on 4) The MEMS wireless temperature measurement system of claim 4, wherein the multimorph sensor further comprises: an electrically insulating pad positioned over and fixed to the electrically conducting substrate, the electrically insulating beams terminate and are anchored at the electrically insulating pad; and an electrically conducting pad positioned over and fixed to the electrically insulating pad, the electrically conducting beams terminate and are anchored at the electrically conducting pad, wherein a combination of the electrically conducting pad, the electrically insulating pad, and the electrically conducting substrate result in a static capacitor, and a combination of the electrically conducting beams, the electrically insulating beams and the electrically conducting substrate result in a temperature-varying capacitor. ### Claim 6 (depends on 5) The MEMS wireless temperature measurement system of claim 5, wherein the first distance corresponds inversely to thermal energy applied to the multimorph sensor. ### Claim 7 (depends on 6) The MEMS wireless temperature measurement system of claim 6, wherein the first distance corresponds inversely to a temperature-varying capacitance of the multimorph sensor. ### Claim 8 (depends on 5) The MEMS wireless temperature measurement system of claim 5, wherein a temperature-varying capacitance of the multimorph sensor corresponds to thermal energy applied to the multimorph sensor. ### Claim 9 (depends on 8) The MEMS wireless temperature measurement system of claim 8, wherein a the relationship between the thermal energy applied to the multimorph sensor and the temperature-varying capacitance of the multimorph sensor is nonlinear. ### Claim 10 (depends on 1) The MEMS wireless temperature measurement system of claim 1, wherein the multimorph sensor and the sensor coil are affixed to a cage of a bearing assembly and the readout coil is affixed to a housing of the bearing assembly. ### Claim 11 A micro-electromechanical system-type (MEMS) sensor arrangement for wirelessly measuring temperatures, comprising: a multimorph sensor; a sensor coil coupled to the multimorph sensor; and a readout coil configured to be magnetically coupled to the sensor coil to i) energize the sensor coil, and ii) provide a readout of a natural frequency of the multimorph sensor, the sensor coil and the readout coil. ### Claim 12 (depends on 11) The MEMS sensor arrangement of claim 11, wherein the multimorph sensor comprises: an electrically conducting substrate with a well area provided thereon; a plurality of electrically insulating beams disposed over the well area of the electrically conducting substrate and fixed to the electrically conducting substrate at a first end and moveable with respect to the well area of the electrically conducting substrate at a second and opposite end of each of the electrically insulating beams; and a plurality of electrically conducting beams, each electrically conducting beam attached to and positioned over a corresponding electrically insulating beam. ### Claim 13 (depends on 12) The MEMS sensor arrangement of claim 12, wherein each of the plurality of electrically conducting beams have thermal expansion characteristics substantially different than each corresponding electrically insulating beam. ### Claim 14 (depends on 13) The MEMS sensor arrangement of claim 13, wherein the second end of each combination of the electrically conducting beam and the corresponding electrically insulating beam is positioned at a first distance with respect to the electrically conducting substrate. ### Claim 15 (depends on 14) The MEMS sensor arrangement of claim 14, further comprising: an electrically insulating pad positioned over and fixed to the electrically conducting substrate, the electrically insulating beams terminate and are anchored at the electrically insulating pad; and an electrically conducting pad positioned over and fixed to the electrically insulating pad, the electrically conducting beams terminate and are anchored at the electrically conducting pad, wherein a combination of the electrically conducting pad, the electrically insulating pad, and the electrically conducting substrate result in a static capacitor, and a combination of the electrically conducting beams, the electrically insulating beams and the electrically conducting substrate result in a temperature-varying capacitor. ### Claim 16 (depends on 15) The MEMS sensor arrangement of claim 15, wherein the first distance corresponds inversely to thermal energy applied to the multimorph sensor. ### Claim 17 (depends on 16) The MEMS sensor arrangement of claim 16, wherein the first distance corresponds inversely to a temperature-varying capacitance of the multimorph sensor. ### Claim 18 (depends on 15) The MEMS sensor arrangement of claim 15, wherein a temperature-varying capacitance of the multimorph sensor corresponds to thermal energy applied to the multimorph sensor. ### Claim 19 (depends on 18) The MEMS sensor arrangement of claim 18, wherein a relationship between the thermal energy applied to the multimorph sensor and the temperature-varying capacitance of the multimorph sensor is nonlinear. ### Claim 20 (depends on 11) The MEMS sensor arrangement of claim 11, wherein the multimorph sensor and the sensor coil are affixed to a cage of a bearing assembly and the readout coil is affixed to a housing of the bearing assembly. ### Claim 21 A method of making a micro-electromechanical system-type (MEMS) sensor arrangement for wirelessly measuring temperatures, comprising: thermally growing an electrically insulating layer over an electrically conducting substrate; depositing an electrically conducting layer over the electrically insulating layer; patterning and etching away to generate a combination of an electrically conducting pad, an electrically insulating pad, a plurality of electrically conducting beams and a plurality of electrically insulating beams, the plurality of the electrically conducting beams terminating and being anchored by the electrically conducting pad, and the plurality of the electrically insulating beams terminating and being anchored by the electrically insulating pad; and etching a well area under the electrically conducting beams and the electrically insulating beams. ### Claim 22 (depends on 21) The method of claim 21, wherein the patterning and etching away step is accomplished by a self-aligning process. ### Claim 23 (depends on 21) The method of claim 21, wherein the patterning and etching away step is accomplished by a lift off process using a sacrificial layer. ### Claim 24 (depends on 21) The method of claim 21, further comprising: patterning and etching the electrically insulating layer; and patterning and etching the electrically conducting layer. ### Claim 25 (depends on 21) The method of claim 21, further comprising: packaging the combination of the electrically conducting pad, the electrically insulating pad, the plurality of electrically insulating beams and the plurality of electrically conducting beams with the electrically conducting substrate to form a package; and annealing the package.