Composite Sensor and Method for Manufacturing The Same

• US 20140260612A1
• Filed: 11/28/2011
• Published: 09/18/2014
• Est. Priority Date: 11/28/2011
• Status: Abandoned Application

• Current Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Suzuki, Kengo, Hayashi, Masahide, Jeong, Heewon, Aono, Takanori
• Application Number:
  US14/353,635
• Publication Number:
  US 20140260612A1
• Time in Patent Office: Days
• US Class Current: 73/504.12
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/0242 Gyroscopes
• CPC Class Codes: B81C 1/00285 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters
• CPC Class Codes: G01C 19/5705 using masses driven in reciprocating rotary motion about an axis
• CPC Class Codes: G01C 19/5783 Mountings or housings not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 2015/088 for providing wafer-level encapsulation

Abstract

The disclosure provides a composite sensor with high reliability and a method for manufacturing the same. A moving body of an acceleration sensor and an oscillator of an angular velocity sensor are provided on the same sensor wafer, while being partitioned by a wall, and a cap wafer is formed to have a gap that corresponds to each of the sensors. A through hole and a bump are formed in a sensor sealing portion, the acceleration sensor is sealed in an air atmosphere in a first sealing process, and in a second sealing process, the angular velocity sensor is sealed by bringing the sensors and the cap into contact with each other and joining the sensors and the cap in a vacuum atmosphere. Thereafter, a composite sensor wafer is cut, a circuit board and a wiring board are mounted thereon, and a composite sensor is formed.

Claims

1. A composite sensor that is configured to have a sensor wafer which has an angular velocity detection unit that detects an angular velocity by using an oscillator, and an acceleration detection unit that detects acceleration by using a moving body, which are respectively provided in spaces partitioned by a wall, and which has a through hole formed in either an area of the angular velocity detection unit or a joint portion;

and a cap wafer in which a gap is formed at each of locations that correspond to the sensors, and a bump is formed in the vicinity of the through hole formed in the angular velocity detection unit,

wherein the sensor is manufactured by;

a process of sealing the acceleration detection unit in an air atmosphere, which is a first sealing process;

a process of sealing the angular velocity detection unit at a high temperature and a high load in a vacuum atmosphere, which is a second sealing process;

a process of dicing a composite sensor wafer into a composite sensor chip by a cutting;

a process of providing a circuit board that compensates for a detection on a wiring board that has an external input and output terminal;

a process of providing the composite sensor chip on the circuit board;

a process of connecting the composite sensor chip, the circuit board, and the wiring board to each other via a wire; and

a process of sealing the composite sensor chip and the circuit board except for a part of the wiring board with a resin.

3. The composite sensor according to claim 1,

wherein the sensor wafer is made of a silicon substrate or a substrate configured to have a silicon oxide layer formed between silicon and silicon, and

wherein the cap wafer is made of a glass substrate or a silicon substrate.

4. The composite sensor according to claim 1,

wherein the bump has a diameter of 10 μ

m or larger and a height of 0.5 μ

m or larger.

5. The composite sensor according to claim 4,

wherein the bump is made of glass or a metal.

6. The composite sensor according to claim 1,

wherein a first-axis angular velocity detection unit and a second-axis acceleration detection unit are provided on the same plane, and detection axes of the angular velocity detection unit and the acceleration detection unit are orthogonal to each other.

2. A composite sensor that is configured to have a sensor wafer which has an angular velocity detection unit that detects an angular velocity by using an oscillator, and an acceleration detection unit that detects acceleration by using a moving body which are provided, respectively, in spaces partitioned by a wall, and which has a through hole formed in either an area of the acceleration detection unit or a joint portion;

and a cap wafer in which a gap is formed at each of locations that correspond to the sensors, and a bump is formed in the vicinity of the through hole formed in the acceleration detection unit,

wherein the sensor is manufactured by;

a process of sealing the angular velocity detection unit in a low vacuum atmosphere, which is a first sealing process;

a process of sealing the acceleration detection unit at a high temperature and a high load in an air atmosphere, which is a second sealing process;

a process of dicing a composite sensor wafer into a composite sensor chip by a cutting;

a process of providing a circuit board that compensates for a detection on a wiring board that has an external input and output terminal;

a process of providing the composite sensor chip on the circuit board;

a process of connecting the composite sensor chip, the circuit board, and the wiring board to each other via a wire; and

a process of sealing the composite sensor chip and the circuit board except for a part of the wiring board with a resin.

7. The composite sensor according to claim 2,

wherein the sensor wafer is made of a silicon substrate or a substrate configured to have a silicon oxide layer formed between silicon and silicon, and

wherein the cap wafer is made of a glass substrate or a silicon substrate.

8. The composite sensor according to claim 2,

wherein the bump has a diameter of 10 μ

m or larger and a height of 0.5 μ

m or larger.

9. The composite sensor according to claim 2,

wherein a first-axis angular velocity detection unit and a second-axis acceleration detection unit are provided on the same plane, and detection axes of the angular velocity detection unit and the acceleration detection unit are orthogonal to each other.