Dual-redundancy pressure sensor of pressure chip suspended packaging and manufacturing method thereof

Abstract

The application discloses a double-redundancy pressure sensor of a pressure chip suspension package, which comprises a corrugated diaphragm (1), a base metal body (2), an oil filling hole (3), a pressing ring (5), silicon oil (6), a gold wire (7), a first pressure chip (9-1), a second pressure chip (9-2), a glass insulator (10), a first group of Kovar alloy pins (11-1) and a second group of Kovar alloy pins (11-2). The application can simply and at low cost avoid hysteresis and repeatability problems.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, and more particularly to a dual-redundancy pressure sensor with pressure chip suspension packaging and a manufacturing method thereof. BACKGROUND

[0002] The dual-redundancy pressure sensor has a main pressure chip and a backup pressure chip. When the main pressure chip fails, the backup pressure chip immediately becomes the main pressure chip to continue working, thereby improving the reliability of a single measurement point, greatly reducing the risk and danger caused by the failure of the original single pressure chip, increasing the use time of the equipment, and reducing the economic cost of replacing the pressure sensor.

[0003] Currently, the dual-redundancy pressure sensor on the market is basically prepared by using the traditional oil-filled isolation process. The traditional oil-filled isolation process first bonds the back of the pressure chip to the sintered base with die bonding glue, and then completes the preparation of the dual-redundancy pressure sensor through steps such as gold wire bonding, isolation diaphragm welding, oil filling, and hole sealing. However, in a high-low temperature environment, the die bonding glue on the back of the pressure chip will harden and expand, which will increase the hysteresis and repeatability problems of the sensor, especially when the pressure is high. To solve these problems, better glue materials are generally used, but better glue materials also bring new material and new process verification work, and also increase the production cost.

[0004] Therefore, how to provide a dual-redundancy pressure sensor with pressure chip suspension packaging and a manufacturing method thereof, which can simply and low-cost avoid hysteresis and repeatability problems is a problem that those skilled in the art need to solve. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a dual-redundancy pressure sensor with pressure chip suspension packaging and a manufacturing method thereof, which can simply and low-cost avoid hysteresis and repeatability problems.

[0006] To achieve the above purpose, the present application adopts the following technical solutions:

[0007] A dual-redundancy pressure sensor with pressure chip suspension packaging, comprising a corrugated diaphragm, a base metal body, an oil filling hole, a pressure ring, silicon oil, gold wire, a first pressure chip, a second pressure chip, a glass insulator, a first group of Kovar alloy pins, and a second group of Kovar alloy pins.

[0008] The first group of Kovar alloy pins and the second group of Kovar alloy pins are fixedly connected with the base metal body through the glass insulator.

[0009] The first pressure chip is fixedly connected to the first set of Kovar alloy pins, and the first pressure chip is suspended and fixed in a first area encircled by the first set of Kovar alloy pins; wherein the first area is used to ensure that there is no space for horizontal displacement of the first pressure chip;

[0010] The second pressure chip is fixedly connected to the second set of Kovar alloy pins, and the second pressure chip is suspended and fixed in a second area encircled by the second set of Kovar alloy pins; wherein the second area is used to ensure that there is no space for the second pressure chip to move in the horizontal direction;

[0011] Each of the Kovar alloy pins in the first group of Kovar alloy pins is connected to the first pressure chip through the gold wire;

[0012] Each of the Kovar alloy pins in the second group of Kovar alloy pins is connected to the second pressure chip through the gold wire;

[0013] The pressure ring is fixedly connected to the base metal body through the corrugated diaphragm;

[0014] The silicone oil is injected into the dual-redundancy pressure sensor through the oil filling hole on the base metal body.

[0015] Preferably, the dual-redundant pressure sensor further includes a ceramic sheet;

[0016] The ceramic sheet is fixedly nested inside the metal body of the base; wherein, the ceramic sheet is provided with the oil filling hole, the first pressure chip, the second pressure chip, the first group of Kovar alloy pins and the second group of Kovar alloy pins matching grooves.

[0017] Preferably, the dual-redundant pressure sensor further includes a steel ball;

[0018] The steel ball is welded to the oil filling hole.

[0019] Preferably, the first group of Kovar pins and the second group of Kovar pins each include 5 gold-plated Kovar pins.

[0020] Preferably, the five gold-plated Kovar pins in the first group of Kovar pins are connected to the side of the first pressure chip through die-bonding glue;

[0021] The five gold-plated Kovar pins in the second group of Kovar pins are connected to the side surface of the second pressure chip through die-bonding glue.

[0022] Preferably, the first group of Kovar alloy pins and the second group of Kovar alloy pins are both sintered and fixed together with the base metal body through the glass insulator.

[0023] Preferably, the pressure ring, the corrugated diaphragm and the base metal body are welded together.

[0024] A method for manufacturing a dual-redundancy pressure sensor with a pressure chip suspended package is provided to realize the manufacturing of the dual-redundancy pressure sensor.

[0025] Preferably, the manufacturing method of the dual-redundancy pressure sensor comprises the following steps:

[0026] S1: placing the first pressure chip within the first area enclosed by the first set of Kovar alloy pins; and fixing the first pressure chip with die-bonding glue at the contact area between the first pressure chip and the first set of Kovar alloy pins;

[0027] Place the second pressure chip in the second area enclosed by the second set of Kovar alloy pins; and secure the second pressure chip to the contact areas between the second set of Kovar alloy pins using die-bonding glue.

[0028] S2: Apply bonding glue to the back of the ceramic sheet and place it inside the metal base.

[0029] S3: Perform the following operations on each of the first group of Kovar pins and the second group of Kovar pins:

[0030] Use gold wire bonding equipment to bond one end of the gold wire to the top pier of the Kovar alloy pin, and the other end to the corresponding point of the corresponding pressure chip;

[0031] S4: Using a pressure ring to press the corrugated diaphragm onto the end surface of the base metal body;

[0032] And weld the pressure ring, corrugated diaphragm and base metal body together;

[0033] S5: Filling silicone oil into the dual-redundancy pressure sensor through the oil filling hole in the vacuum oil filling equipment;

[0034] S6: Use steel balls to seal the oil filling hole through energy storage welding.

[0035] Preferably, in S4, the pressure ring, the corrugated diaphragm and the base metal body are welded together by a laser welding machine or an argon arc welding machine.

[0036] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses a dual-redundancy pressure sensor with a pressure chip suspended package and a manufacturing method thereof, which can achieve the following beneficial technical effects:

[0037] 1) The present invention uses Kovar alloy pins to limit the horizontal movement of the pressure chip and only uses die-bonding glue to fix the pressure chip on the side, avoiding the hysteresis and repeatability problems caused by using die-bonding glue on the back of the pressure chip.

[0038] 2) The present invention only uses the crystal-fixing glue on the side of the pressure chip for fixing, so that the pressure chip is suspended and fixed in the silicone oil, thereby playing a role in protecting the pressure chip.

[0039] 3) Compared with the prior art method of using better glue, the present invention has lower cost and simpler method (it can save the verification work of new materials and new processes);

[0040] 4) The embedded ceramic sheet of the present invention can reduce the oil-filled space, thereby reducing the impact of the decrease in silicone oil pressure transmission performance during high and low temperature changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0042] Figure 1 A cross-sectional view of a dual-redundant pressure sensor provided in one embodiment of the present invention;

[0043] Figure 2 A top view of a dual-redundant pressure sensor provided in one embodiment of the present invention without a corrugated diaphragm welded thereto;

[0044] Figure 3 A schematic diagram of fixing a first pressure chip provided in one embodiment of the present invention;

[0045] Figure 4 An exploded diagram of a dual-redundant pressure sensor provided in one embodiment of the present invention;

[0046] Figure 5 This is a schematic structural diagram of a ceramic sheet provided in one embodiment of the present invention.

[0047] The meaning of the numbers in the accompanying drawings are: 1. Corrugated diaphragm; 2. Base metal body; 3. Oil filling hole; 4. Steel ball; 5. Pressure ring; 6. Silicone oil; 7. Gold wire; 8. Ceramic sheet; 9-1. First pressure chip; 9-2. Second pressure chip; 10. Glass insulator; 11-1. First set of Kovar alloy pins; 11-2. Second set of Kovar alloy pins; 12. Glue. DETAILED DESCRIPTION

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0049] like Figure 1-Figure 5 As shown, the embodiment of the present invention discloses a dual-redundancy pressure sensor with a pressure chip suspended package, including a corrugated diaphragm 1, a base metal body 2, an oil filling hole 3, a pressure ring 5, silicone oil 6, a gold wire 7, a first pressure chip 9-1, a second pressure chip 9-2, a glass insulator 10, a first group of Kovar alloy pins 11-1 and a second group of Kovar alloy pins 11-2;

[0050] The first group of Kovar alloy pins 11-1 and the second group of Kovar alloy pins 11-2 are both fixedly connected to the base metal body 2 through the glass insulator 10;

[0051] The first pressure chip 9-1 is fixedly connected to the first set of Kovar alloy pins 11-1, and the first pressure chip 9-1 is suspended and fixed in a first area enclosed by the first set of Kovar alloy pins 11-1; wherein the first area is used to ensure that there is no space for horizontal displacement of the first pressure chip 9-1;

[0052] The second pressure chip 9-2 is fixedly connected to the second set of Kovar alloy pins 11-2, and the second pressure chip 9-2 is suspended and fixed in a second area encircled by the second set of Kovar alloy pins 11-2; wherein the second area is used to ensure that the second pressure chip 9-2 has no space for horizontal displacement;

[0053] Each of the Kovar alloy pins in the first group of Kovar alloy pins 11-1 is connected to the first pressure chip 9-1 through the gold wire 7;

[0054] Each of the Kovar alloy pins in the second group of Kovar alloy pins 11-2 is connected to the second pressure chip 9-2 via the gold wire 7;

[0055] The pressure ring 5 is fixedly connected to the base metal body 2 through the corrugated diaphragm 1;

[0056] The silicone oil 6 is injected into the dual-redundancy pressure sensor through the oil filling hole 3 on the base metal body 2.

[0057] It is understandable that:

[0058] The corrugated diaphragm 1 of the present invention is used to transmit the pressure of the measured medium;

[0059] The base metal body 2 of the present invention is the main structure of the dual-redundancy pressure sensor, which plays the role of supporting and protecting the entire dual-redundancy pressure sensor;

[0060] The pressure ring 5 is used to compress the corrugated diaphragm 1;

[0061] The silicone oil 6 is used to transmit pressure;

[0062] The gold wire 7 is used to supply power to the first pressure chip 9-1 and the second pressure chip 9-2, and transmit the electrical signals output by the first pressure chip 9-1 and the second pressure chip 9-2;

[0063] The first pressure chip 9-1 and the second pressure chip 9-2 are used to convert the pressure signal into an electrical signal;

[0064] The functions of the glass insulator are: 1) fixing each Kovar alloy pin in the first group of Kovar alloy pins 11-1 and the second group of Kovar alloy pins 11-2; 2) ensuring that the base metal body 2 and each Kovar alloy pin (each Kovar alloy pin in the first group of Kovar alloy pins 11-1 and the second group of Kovar alloy pins 11-2) are insulated.

[0065] The functions of each Kovar pin in the first group of Kovar pins 11-1 and the second group of Kovar pins 11-2 are:

[0066] 1) Serves as an anchor point for gold wire bonding;

[0067] 2) Each Kovar pin in the first group of Kovar pins 11-1 is used to transmit the electrical signal output by the first pressure chip 9-1; each Kovar pin in the second group of Kovar pins 11-2 is used to transmit the electrical signal output by the second pressure chip 9-2;

[0068] 3) Used to access sensor excitation (i.e., sensor excitation supplies power to the sensor through the Kovar alloy pin).

[0069] In one embodiment, the dual-redundant pressure sensor further includes a ceramic sheet 8;

[0070] The ceramic sheet 8 is fixedly nested inside the base metal body 2; wherein, the ceramic sheet 8 is provided with the oil filling hole 3, the first pressure chip 9-1, the second pressure chip 9-2, the first group of Kovar alloy pins 11-1 and the second group of Kovar alloy pins 11-2 adaptation grooves.

[0071] It can be understood that the ceramic sheet 8 is used to reduce the oil-filled space, thereby reducing the impact of the silicone oil pressure transmission performance degradation during high and low temperature changes. In addition, the adaption groove provided on the ceramic sheet can separate the first pressure chip 9-1 and the second pressure chip 9-2, and can also prevent the gold wires 7 from short-circuiting with each other and with the top corrugated diaphragm 1.

[0072] In one embodiment, the dual-redundant pressure sensor further includes a steel ball 4;

[0073] The steel ball 4 is welded to the oil filling hole 3 .

[0074] Specifically, the oil filling hole 3 is sealed with a steel ball 4 by energy storage welding;

[0075] In one embodiment, the first group of Kovar pins 11 - 1 and the second group of Kovar pins 11 - 2 each include five gold-plated Kovar pins.

[0076] In one embodiment, the five gold-plated Kovar pins in the first group of Kovar pins 11-1 are connected to the side of the first pressure chip 9-1 through die-bonding glue 12;

[0077] The five gold-plated Kovar pins in the second group of Kovar pins 11 - 2 are connected to the side surface of the second pressure chip 9 - 2 through the die-bonding glue 12 .

[0078] In one embodiment, the first group of Kovar alloy pins 11 - 1 and the second group of Kovar alloy pins 11 - 2 are both sintered and fixed to the base metal body 2 through the glass insulator 10 .

[0079] It can be understood that the glass insulator 10, the base metal body 2, the first group of Kovar alloy pins 11-1 and the second group of Kovar alloy pins 11-2 constitute the sintered base of the dual-redundant pressure sensor;

[0080] In one embodiment, the pressure ring 5 , the corrugated diaphragm 1 and the base metal body 2 are welded together.

[0081] The embodiment of the present invention further discloses a method for manufacturing a dual-redundant pressure sensor with a pressure chip suspended package, thereby realizing the manufacturing of the dual-redundant pressure sensor.

[0082] In one embodiment, a method for manufacturing a dual-redundant pressure sensor includes the following steps:

[0083] S1: Place the first pressure chip 9-1 within the first area enclosed by the first set of Kovar alloy pins 11-1; and secure the first pressure chip 9-1 and the first set of Kovar alloy pins 11-1 at their side contact locations with die-bonding glue 12;

[0084] Place the second pressure chip 9-2 within the second area enclosed by the second set of Kovar alloy pins 11-2; and secure the second pressure chip 9-2 and the second set of Kovar alloy pins 11-2 at their side contact locations with die-bonding glue 12;

[0085] S2: Apply the bonding glue 12 on the back of the ceramic sheet 8 and place it in the base metal body 2;

[0086] S3: Perform the following operations on each of the first group of Kovar pins 11-1 and the second group of Kovar pins 11-2:

[0087] Use gold wire bonding equipment to bond one end of the gold wire to the top pier of the Kovar alloy pin, and the other end to the corresponding point of the corresponding pressure chip;

[0088] S4: Using the pressure ring 5 to press the corrugated diaphragm 1 onto the end surface of the base metal body 2;

[0089] And weld the pressure ring 5, the corrugated diaphragm 1 and the base metal body 2 together;

[0090] S5: Filling the silicone oil 6 into the dual-redundancy pressure sensor through the oil filling hole 3 in the vacuum oil filling device;

[0091] S6: Use steel balls 4 to seal the oil filling hole 3 through energy storage welding.

[0092] Preferably, in S4, the pressure ring 5, the corrugated diaphragm 1 and the base metal body 2 are welded together by a laser welding machine or an argon arc welding machine.

[0093] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0094] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A dual-redundancy pressure sensor with a pressure chip suspended package, characterized in that: It comprises a corrugated diaphragm (1), a base metal body (2), an oil filling hole (3), a pressure ring (5), silicone oil (6), a gold wire (7), a first pressure chip (9-1), a second pressure chip (9-2), a glass insulator (10), a first group of Kovar alloy pins (11-1) and a second group of Kovar alloy pins (11-2); The first group of Kovar alloy pins (11-1) and the second group of Kovar alloy pins (11-2) are both fixedly connected to the base metal body (2) via the glass insulator (10); The first pressure chip (9-1) is fixedly connected to the first group of Kovar alloy pins (11-1), and the first pressure chip (9-1) is suspended and fixed in a first area encircled by the first group of Kovar alloy pins (11-1); wherein the first area is used to ensure that the first pressure chip (9-1) has no displacement space in the horizontal direction; The second pressure chip (9-2) is fixedly connected to the second group of Kovar alloy pins (11-2), and the second pressure chip (9-2) is suspended and fixed in a second area encircled by the second group of Kovar alloy pins (11-2); wherein the second area is used to ensure that the second pressure chip (9-2) has no displacement space in the horizontal direction; Each of the Kovar alloy pins in the first group of Kovar alloy pins (11-1) is connected to the first pressure chip (9-1) via the gold wire (7); Each of the Kovar alloy pins in the second group of Kovar alloy pins (11-2) is connected to the second pressure chip (9-2) via the gold wire (7); The pressure ring (5) is fixedly connected to the base metal body (2) via the corrugated diaphragm (1); The silicone oil (6) is injected into the interior of the dual-redundancy pressure sensor through the oil filling hole (3) on the base metal body (2); Also includes a ceramic sheet (8); The ceramic sheet (8) is fixedly nested inside the base metal body (2); wherein, the ceramic sheet (8) is provided with the oil filling hole (3), the first pressure chip (9-1), the second pressure chip (9-2), the first group of Kovar alloy pins (11-1) and the second group of Kovar alloy pins (11-2) matching grooves.

2. The dual-redundancy pressure sensor with a pressure chip suspended package according to claim 1 is characterized in that: Also includes a steel ball (4); The steel ball (4) is welded to the oil filling hole (3).

3. The dual-redundancy pressure sensor with a pressure chip suspended package according to claim 1, characterized in that: The first group of Kovar alloy pins (11-1) and the second group of Kovar alloy pins (11-2) both include five gold-plated Kovar alloy pins.

4. The dual-redundancy pressure sensor with a pressure chip suspended package according to claim 3, characterized in that: Five gold-plated Kovar pins in the first group of Kovar pins (11-1) are connected to the side of the first pressure chip (9-1) via a die-bonding glue (12); Five gold-plated Kovar pins in the second group of Kovar pins (11-2) are connected to the side of the second pressure chip (9-2) via die-bonding glue (12).

5. The dual-redundancy pressure sensor with a pressure chip suspended package according to claim 1, characterized in that: The first group of Kovar alloy pins (11-1) and the second group of Kovar alloy pins (11-2) are both sintered and fixed together with the base metal body (2) through the glass insulator (10).

6. The dual-redundancy pressure sensor with a pressure chip suspended package according to claim 1, characterized in that: The pressure ring (5), the corrugated diaphragm (1) and the base metal body (2) are welded together.

7. A method for manufacturing a dual-redundancy pressure sensor with a pressure chip suspended package, characterized in that: The dual-redundancy pressure sensor according to any one of claims 1 to 6 is manufactured.

8. The method for manufacturing a dual-redundancy pressure sensor with a pressure chip suspended package according to claim 7, characterized in that: The following steps are involved: S1: placing the first pressure chip (9-1) in the first area enclosed by the first group of Kovar alloy pins (11-1); and fixing the first pressure chip (9-1) and the first group of Kovar alloy pins (11-1) at the contact portion of the side surface with the die-bonding glue (12); The second pressure chip (9-2) is placed in the second area enclosed by the second group of Kovar alloy pins (11-2); and the second pressure chip (9-2) is fixed with a die-bonding glue (12) at the contact portion between the side surfaces of the second pressure chip (9-2) and the second group of Kovar alloy pins (11-2); S2: Applying a crystal-fixing glue (12) to the back of the ceramic sheet (8) and placing it inside the base metal body (2); S3: Perform the following operations on each of the first group of Kovar pins (11-1) and the second group of Kovar pins (11-2): Use gold wire bonding equipment to bond one end of the gold wire to the top pier of the Kovar alloy pin, and the other end to the corresponding point of the corresponding pressure chip; S4: Using a pressure ring (5), the corrugated diaphragm (1) is pressed against the end surface of the base metal body (2); and the pressure ring (5), the corrugated diaphragm (1) and the base metal body (2) are welded together; S5: Filling the silicone oil (6) into the dual-redundancy pressure sensor through the oil filling hole (3) in the vacuum oil filling device; S6: Use a steel ball (4) to seal the oil filling hole (3) through energy storage welding.

9. The method for manufacturing a dual-redundancy pressure sensor with a pressure chip suspended package according to claim 8, characterized in that: The pressure ring (5), the corrugated diaphragm (1) and the base metal body (2) in S4 are welded together by a laser welding machine or an argon arc welding machine.

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