Monolithic multi-functional integrated sensor and method for fabricating the same
A monolithic multi-functional integrated sensor and method for making the monolithic multi-functional integrated sensor. The monolithic multi-functional integrated sensor includes: a pressure sensor including a plurality of piezoresistors having resistance values which vary with a change in external pressure, the piezoresistors being disposed in a direction so as to be subject to a piezoresistive effect produced by the external pressure at or beyond a predetermined first level; and a temperature sensor including a resistor having a resistance value which varies with a change in temperature, the resistor being disposed in a direction so as to be subject to a piezoresistive effect produced by the external pressure below a predetermined second level.
1. A monolithic multi-functional integrated sensor comprising:
a pressure sensor comprising a plurality of piezoresistors having resistance values which vary with a change in external pressure, the piezoresistors being disposed in a direction so as to be subject to a piezoresistive effect produced by the external pressure at or beyond a predetermined first level; and
a temperature sensor comprising a resistor having a resistance value which varies with a change in temperature, the resistor being disposed in a direction so as to be subject to a piezoresistive effect produced by the external pressure below a predetermined second level.
2. The monolithic multi-functional integrated sensor of claim 1 , wherein when external pressure is applied in a z-axis direction 001 , the plurality of piezoresistors of the pressure sensor are disposed within ±5° in an x-axis direction 100 or within ±5° in a y-axis direction 010 .
3. The monolithic multi-functional integrated sensor of claim 1 , wherein the piezoresistors are disposed in a direction which maximizes a piezoresistive effect produced by the external pressure, and the resistor is disposed in a direction which minimizes the piezoresistive effect produced by the external pressure.
4. The monolithic multi-functional integrated sensor of claim 3 , wherein when the external pressure is applied in a z-axis direction 001 , the plurality of piezoresistors of the pressure sensor are disposed in one of an x-axis direction 100 and a y-axis direction 010 .
5. The monolithic multi-functional integrated sensor of claim 4 , wherein the plurality of piezoresistors are patterns which zigzag alternately a predetermined number of times in the x-axis direction 100 and the y-axis direction 010 .
6. The monolithic multi-functional integrated sensor of claim 1 , wherein when external pressure is applied in the z-axis direction 001 , the resistor of the temperature sensor is disposed from about 40° to about 50° or from about −50° to about −40° with respect to the y-axis direction 010 on an x-y plane.
7. The monolithic multi-functional integrated sensor of claim 6 , wherein when the external pressure is applied in a z-axis direction 001 , the resistor of the temperature sensor is disposed in one of a direction 110 of about 45° and a direction − 110 of about −45° with respect to a y-axis direction 010 on an x-y plane.
8. The monolithic multi-functional integrated sensor of claim 7 , wherein the resistor is a pattern which zigzags alternately a predetermined number of times in the 110 and − 110 directions.
9. The monolithic multi-functional integrated sensor of claim 1 , wherein an angle between the disposed direction of the plurality of piezoresistors and the disposed direction of the resistor ranges from about 40° to about 50°.
10. The monolithic multi-functional integrated sensor of claim 9 , wherein an angle between the disposed direction of the plurality of piezoresistors and the disposed direction of the resistor is about 45°.
11. A method for fabricating a monolithic multi-functional integrated sensor for sensing external pressure and temperature, comprising:
forming a plurality of piezoresistors having resistance values which vary with a change in external pressure in a direction so as to be subject to a piezoresistive effect produced by the external pressure beyond a predetermined first level; and
forming a resistor having a resistance value which varies with a change in temperature in a direction so as to be subject to a piezoresistive effect produced by the external pressure below a predetermined second level.
12. The method of claim 11 , wherein when external pressure is applied in a z-axis direction 001 , the plurality of piezoresistors of the pressure sensor are disposed within ±5° in an x-axis direction 100 or within ±5° in a y-axis direction 010 .
13. The method of claim 11 , wherein the piezoresistors are disposed in a direction which maximizes a piezoresistive effect produced by the external pressure, and the resistor is disposed in a direction which minimizes the piezoresistive effect produced by the external pressure.
14. The method of claim 13 , wherein when the external pressure is applied in a z-axis direction 001 , the plurality of piezoresistors are formed in one of an x-axis direction 100 and a y-axis direction 010 .
15. The method of claim 14 , wherein the plurality of piezoresistors are each formed in a pattern which zigzags alternately a predetermined number of times in the x-axis direction 100 and the y-axis direction 010 .
16. The method of claim 11 , wherein when external pressure is applied in the z-axis direction 001 , the resistor of the temperature sensor may be disposed from about 40° to about 50° or from about −50° to about −40° with respect to the y-axis direction 010 on an x-y plane.
17. The method of claim 16 , wherein when the external pressure is applied in a z-axis direction 001 , the resistor is formed in one of a direction 110 of about 45° and a direction − 110 of about −45° with respect to the y-axis direction 010 on an x-y plane.
18. The method of claim 17 , wherein the resistor is formed in a pattern which zigzags alternately a predetermined number of times in the 110 and − 110 directions.
19. The method of claim 11 , wherein an angle between the disposed direction of the plurality of piezoresistors and the disposed direction of the resistor ranges from about 40° to about 50°.
20. The method of claim 19 , wherein an angle between the disposed direction of the plurality of piezoresistors and the disposed direction of the resistor is about 45°.