Integrated inertial sensor and pressure sensor, and forming method therefor

• US 9,448,251 B2
• Filed: 02/23/2012
• Issued: 09/20/2016
• Est. Priority Date: 03/15/2011
• Status: Active Grant

• Current Assignee: Memsen Electronics, Inc.
• Original Assignee: Memsen Electronics, Inc.
• Inventors: Liu, Lianjun
• Primary Examiner(s): Chapman, Jr., John
• Application Number:
  US14/004,595
• Publication Number:
  US 20130340525A1
• Time in Patent Office: 1,671 Days
• Field of Search: 735/143.2, 737/14
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/025 Inertial sensors not provided for in B81B2201/0235 - B81B2201/0242
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 7/02 containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] B81B7/04 takes precedence
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: G01C 19/5769 Manufacturing; Mounting; Housings
• CPC Class Codes: G01P 15/02 by making use of inertia forces using solid seismic massesG01P15/14 takes precedence
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: H01L 29/84 controllable by variation of applied mechanical force, e.g. of pressure

Abstract

An integrated inertial sensor and pressure sensor may include a first substrate including a first surface and a second surface; at least one or more conductive layers, formed on the first surface of the first substrate; a movable sensitive element, formed by using a first region of the first substrate; a second substrate and a third substrate, the second substrate being coupled to a surface of the conductive layer, the third substrate being coupled to the second surface of the first substrate in which the movable sensitive element of the inertial sensor is formed, and the third substrate and the second substrate are respectively arranged on opposite sides of the movable sensitive element; and a sensitive film of the pressure sensor, including at least a second region of the first substrate, or including at least one of the conductive layers on the second region of the first substrate.

Claims

1. An integrated inertial sensor and pressure sensor, comprising:

a first substrate comprising a first surface and a second surface opposite to the first surface, and the first substrate comprising a first region and a second region;

at least one or more conductive layers, deposited on the first surface of the first substrate, wherein the at least one or more conductive layers comprises a first electrical shielding layer for the inertial sensor, and wherein the first electrical shielding layer is electrically connected to the first substrate through one or more vias with the one or more vias only between the first electrical shielding and the first substrate;

a movable sensitive element of the inertial sensor, formed by using the first region of the first substrate;

a second substrate and a third substrate, the second substrate being coupled to a surface of the conductive layer on the first surface of the first substrate, the third substrate being coupled to the second surface of the first substrate in which the movable sensitive element of the inertial sensor is formed, and the third substrate and the second substrate are respectively arranged on two opposite sides of the movable sensitive element of the inertial sensor; and

a sensitive film of the pressure sensor, comprising at least the second region of the first substrate, or comprising at least one of the conductive layers on the second region of the first substrate.

2. The integrated inertial sensor and pressure sensor according to claim 1, wherein the first substrate is formed of monocrystalline semiconductor material.

3. The integrated inertial sensor and pressure sensor according to claim 1, wherein the at least one or more conductive layers further comprise an electrical interconnecting layer for the inertial sensor.

4. The integrated inertial sensor and pressure sensor according to claim 3, wherein in a case that the sensitive film of the pressure sensor comprises one of the conductive layers on the second region of the first substrate, the sensitive film comprises a material layer which is the same layer as that for forming the first electrical shielding layer for the inertial sensor, or comprises a material layer which is the same layer as that for forming the electrical interconnecting layer for the inertial sensor.

5. The integrated inertial sensor and pressure sensor according to claim 4, wherein in a case that the sensitive film of the pressure sensor comprises one of the conductive layers on the second region of the first substrate, a fixed electrode of the pressure sensor is formed by using the second region of the first substrate, and a through hole is formed in the fixed electrode of the pressure sensor.

6. The integrated inertial sensor and pressure sensor according to claim 1, wherein the at least one or more conductive layers further comprises an electrical interconnecting layer for the inertial sensor, and the electrical interconnecting layer is closer to the first surface of the first substrate than the first electrical shielding layer.

7. The integrated inertial sensor and pressure sensor according to claim 1, wherein in a case that the sensitive film of the pressure sensor comprises one of the conductive layers on the second region of the first substrate, a fixed electrode of the pressure sensor is formed by using another layer of the conductive layers on the second region of the first substrate, or formed by using the second region of the first substrate, or formed by using a conductive material layer on the third substrate.

8. The integrated inertial sensor and pressure sensor according to claim 1, wherein in a case that the sensitive film of the pressure sensor comprises at least one of the conductive layers on the second region of the first substrate, the integrated inertial sensor and pressure sensor further comprises a fixed electrode of the pressure sensor opposite to the sensitive film of the pressure sensor, and a movable sensitive element of the pressure sensor formed between the sensitive film of the pressure sensor and the fixed electrode of the pressure sensor, wherein the movable sensitive element of the pressure sensor is connected with the sensitive film by a connecting arm, and a through hole is formed in the movable sensitive element of the pressure sensor.

9. The integrated inertial sensor and pressure sensor according to claim 1, wherein the sensitive film of the pressure sensor comprises a plurality of layers;

the plurality of layers comprises at least one of the conductive layers.

10. The integrated inertial sensor and pressure sensor according to claim 1, further comprising:

a pressure port opening, through which the sensitive film of the pressure sensor is exposed.

11. The integrated inertial sensor and pressure sensor according to claim 1, wherein in a case that the sensitive film of the pressure sensor comprises the second region of the first substrate, a fixed electrode of the pressure sensor is formed by using a layer of the conductive layers on the second region of the first substrate, or formed by using a conductive material layer on the third substrate.

12. A method for forming an integrated inertial sensor and pressure sensor, comprising:

providing a first substrate, wherein the first substrate comprises a first surface and a second surface opposite to the first surface, and the first substrate comprises a first region and a second region;

depositing one or more conductive layers on the first surface of the first substrate, wherein depositing the one or more conductive layers comprises;

depositing a first electrical shielding layer for the inertial sensor and forming one or more vias, wherein the one or more vias electrically connect the first electrical shielding layer to the first substrate and are only between the first electrical shielding layer and the first substrate;

providing a second substrate and a third substrate;

coupling the second substrate to a surface of the conductive layer on the first surface of the first substrate after the one or more conductive layers are deposited;

forming a movable sensitive element of the inertial sensor by using the first region of the first substrate;

forming a sensitive film of the pressure sensor, wherein the sensitive film comprises at least the second region of the first substrate, or comprises at least one of the conductive layers on the second region of the first substrate; and

coupling the third substrate to the second surface of the first substrate in which the movable sensitive element of the inertial sensor is formed, wherein the third substrate and the second substrate are respectively arranged on two opposite sides of the movable sensitive element of the inertial sensor.

13. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein the first substrate is formed of monocrystalline semiconductor material.

14. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein the depositing the one or more conductive layers further comprises:

depositing an electrical interconnecting layer for the inertial sensor, and the electrical interconnecting layer is closer to the first surface of the first substrate than the first electrical shielding layer.

15. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein in a case that the sensitive film of the pressure sensor comprises one of the conductive layers on the second region of the first substrate, the method further comprises:

forming a fixed electrode of the pressure sensor by using another layer of the conductive layers on the second region of the first substrate, or by using the second region of the first substrate, or by using a conductive material layer on the third substrate.

16. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein in a case that the sensitive film of the pressure sensor comprises one of the conductive layers on the second region of the first substrate, the method further comprises:

forming a fixed electrode of the pressure sensor by using the second region of the first substrate, and

forming a through hole in the fixed electrode of the pressure sensor.

17. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein in a case that the sensitive film of the pressure sensor comprises at least one of the conductive layers on the second region of the first substrate, the method further comprises:

forming a fixed electrode of the pressure sensor opposite to the sensitive film of the pressure sensor, wherein the fixed electrode of the pressure sensor is formed by using the second region of the first substrate;

forming a movable sensitive element of the pressure sensor between the sensitive film of the pressure sensor and the fixed electrode of the pressure sensor, wherein the movable sensitive element of the pressure sensor is formed by using another layer of the conductive layers;

forming a connecting arm between the movable sensitive element of the pressure sensor and the sensitive film for connecting the movable sensitive element of the pressure sensor with the sensitive film; and

forming a through hole in the movable sensitive element of the pressure sensor.

18. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein the sensitive film of the pressure sensor comprises a plurality of layers;

the plurality of layers comprises at least one of the conductive layers on the second region of the first substrate, the sensitive films of the pressure sensor further comprise a material layer above or below the conductive layer the sensitive films of the pressure sensor comprise.

19. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, further comprising forming a pressure port opening through which the sensitive film is exposed.

20. The method for forming the integrated inertial sensor and pressure sensor according to claim 12, wherein in a case that the sensitive film of the pressure sensor comprises the second region of the first substrate, the method further comprises:

forming a fixed electrode of the pressure sensor by using a layer of the conductive layers on the second region of the first substrate, or by using a conductive material layer formed on the third substrate.