CN103824817A - Vacuum ceramic packaging structure of sensor - Google Patents

Abstract

The invention relates to a vacuum ceramic packaging structure of a sensor, comprising a tube shell, a getter, a chip and a germanium window, the germanium window is fixed on the top of the tube shell, the getter and the chip are located on the Inside the tube case; the getter and the chip are respectively fixed on the bottom of the tube case through the getter boss and the chip boss, and the chip is located above the getter. The invention places the getter under the chip, which can greatly reduce the packaging volume, thereby reducing the cost of the device.

Description

Vacuum ceramic packaging structure of the sensor

technical field

The invention relates to an infrared light sensor and other electronic sensors, in particular to a vacuum ceramic package structure of the sensor. the

Background technique

Many electronic devices and sensors need to work in vacuum or other low-pressure inert gases. Among them, the infrared focal plane array of the infrared light sensor needs to work in a vacuum environment. The basic principle of the infrared light sensor is that the sensor absorbs the infrared light emitted by the target object, so that the temperature of the device changes, the resistance of the sensor sensitive unit changes with the temperature, and finally outputs a detectable electrical signal. the

Infrared focal plane arrays require a vacuum-sealed environment for thermal isolation. At present, the commonly used packaging forms of infrared focal plane arrays include metal packaging and ceramic packaging. Due to the high cost of metal packaging, more and more civilian markets have begun to adopt ceramic packaging. Cost will play a decisive role in the growth of the infrared focal plane array market. the

The vacuum degree of infrared focal plane array can reach a good level (a dozen millitorr or even higher) at the initial stage of packaging, but due to the outgassing of the packaging material itself and the leakage rate of the package package, the vacuum degree of the device will drop quickly, so that The device is incapacitated. This greatly reduces the service life of the device, increases the cost of use, and limits market development. Therefore, finding a method to maintain the vacuum degree of the device at a high level for a long time will greatly reduce the cost of using the device. the

In the prior art, the method for maintaining the vacuum degree of the device is to place a getter in the vacuum chamber of the device. When the vacuum degree of the device drops to a certain level, activate the getter so that the vacuum degree of the device continues to meet the use requirements of the device. Thereby prolonging the service life of the device and reducing the cost of use. the

At present, the getter is generally placed side by side with the chip in the package shell. This structure increases the volume of the vacuum chamber, which increases the volume and consumption of the package shell, germanium window and other packaging consumables. At the same time, a larger chamber Resulting in greater vacuum maintenance difficulty. the

Contents of the invention

Aiming at the above problems, the present invention provides a sensor vacuum ceramic packaging structure, which can reduce the packaging volume, thereby reducing the cost of the device. the

According to the technical solution of the present invention: a vacuum ceramic packaging structure of a sensor, comprising a tube shell, a getter, a chip and a germanium window, the germanium window is fixed on the top of the tube shell, the getter and the The chip is located in the tube case; the getter and the chip are respectively fixed on the bottom of the tube case through the getter protrusion and the chip protrusion, and the chip is located above the getter. the

There are two getter bosses, and the two ends of the getter are respectively fixed on the two getter bosses. the

The two ends of the getter are respectively provided with positioning steps. the

There are two chip bosses, and the two ends of the chip are respectively fixed on the two chip bosses. the

The chip and the getter are viewed as a cross structure. the

The shell is made of ceramic material, the boss of the getter is made of Kovar alloy, and the boss of the chip is made of Kovar alloy. the

An exhaust pipe is arranged on the casing, and a sealant is installed on the outer end of the exhaust pipe. the

Both sides of the tube shell are respectively arranged with pins of the tube shell, and the pins of the tube shell on each side are respectively connected with the chip through bonding metal leads. the

The technical effect of the present invention is that: the present invention places the getter under the chip, which can greatly reduce the packaging volume, thereby reducing the cost of the device. the

Description of drawings

Fig. 1 is a top view of the structure of the present invention, wherein the germanium window, getter and chip are removed. the

Fig. 2 is a top view of the structure of the present invention, wherein the germanium window is removed. the

Fig. 3 is a top view of the structure of the present invention. the

Fig. 4 is a front sectional view of the structure of the present invention. the

Detailed ways

The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings. the

In Fig. 1 to Fig. 3, it includes the shell 1, the getter boss 2, the chip boss 3, the getter 4, the chip 5, the exhaust pipe 6, the shell pin 7, the bonding metal lead 8, the germanium Window 9, sealant 10, positioning steps 11, etc. the

As shown in FIGS. 1 to 3 , the present invention is a vacuum ceramic packaging structure of a sensor, including a tube shell 1 , a getter 4 , a chip 5 and a germanium window 9 . The casing 1 is made of ceramic material, and the casing 1 is provided with an exhaust pipe 6 , and a sealant 10 is installed on the outer end of the exhaust pipe 6 . the

The germanium window 9 is fixed on the top of the tube case 1 , and the germanium window 9 is soldered by reflow soldering, and the solder can be selected according to requirements. the

The getter 4 and the chip 5 are located in the package 1 . The getter 4 and the chip 5 are respectively fixed on the bottom of the package 1 through the getter boss 2 and the chip boss 3 , and the chip 5 is located above the getter 4 . The chip 5 and the getter 4 are viewed as a cross structure. the

There are two getter bosses 2, and the two ends of the getter 4 are respectively fixed on the two getter bosses 2. The getter boss 2 is made of Kovar alloy material, and the two ends of the getter 4 are respectively provided with positioning steps 11 . the

There are two chip bosses 3, and the two ends of the chip 5 are respectively fixed on the two chip bosses 3. The chip boss 3 is made of Kovar alloy material. the

Both sides of the package 1 are respectively arranged with package pins 7 , and each side of the package pins 7 is respectively connected to the chip 5 through bonding metal leads 8 . the

The production process of the present invention is described as follows:

1. Getter 4 Installation

As shown in FIG. 1 , the getter pad 2 and the chip pad 3 are soldered first. The material of the boss adopts Kovar alloy, and the welding process can be selected according to the needs, such as brazing or sintering process. There must be a certain height difference between the getter boss 2 and the chip boss 3 so as to accommodate the installation of the getter 4 and the chip 5 . the

The installation of the getter 4 is then carried out, and the getter 4 is welded to the getter boss 2 . The welding process of the getter adopts the spot welding process, as shown in Figure 3. the

2. Chip 5 installation

The placement process of chip 5 is pasted with silver paste. Curing is carried out at 150°C for two hours after mounting. the

After the getter 4 and the chip 5 are installed, wire 8 bonding is performed respectively, as shown in FIG. 2 . the

3. Germanium window 9 welding

The germanium window 9 is welded by reflow soldering, and the solder can be selected according to requirements. the

4. Leak detection

After the germanium window 9 is installed, use a leak detector to detect leaks on the device. If the leak rate detection fails to meet the established targets, it means that the germanium window welding process fails to meet the requirements, and the device will be scrapped. the

5. Exhaust

After the leak detection of the device is passed, the upper exhaust table is exhausted. The exhaust process temperature is 150°C for 48 hours. After the exhaust is completed, the exhaust pipe 6 is cut off for blanking. The exhaust pipe 6 is cut off and sealed by clamp sealing process. the

In the present invention, the getter 4 is placed under the chip 5, which can greatly reduce the packaging volume, thereby reducing the cost of the device. the

Claims (8)

1. a vacuum ceramic packaging structure of a sensor, comprising a tube shell (1), a getter (4), a chip (5) and a germanium window (9), and the germanium window (9) is fixed on the tube shell ( 1), the getter (4) and the chip (5) are located in the shell (1); it is characterized in that: the getter (4) and the chip (5) are respectively The getter boss (2) and the chip boss (3) are fixed on the bottom of the tube case (1), and the chip (5) is located above the getter (4). 2. According to the vacuum ceramic packaging structure of the sensor according to claim 1, it is characterized in that: there are two bosses (2) of the getter, and the two ends of the getter (4) are respectively fixed on the on the two getter bosses (2). 3. The vacuum ceramic packaging structure of the sensor according to claim 2, characterized in that: the two ends of the getter (4) are respectively provided with positioning steps (11). 4. According to the vacuum ceramic packaging structure of the sensor according to claim 1, it is characterized in that: there are two chip bosses (3), and the two ends of the chip (5) are respectively fixed on the two chip bosses. On the platform (3). 5 . The vacuum ceramic packaging structure of the sensor according to claim 1 , characterized in that: the chip ( 5 ) and the getter ( 4 ) are in a cross structure when viewed from above. 5 . 6. The vacuum ceramic packaging structure of the sensor according to claim 1, characterized in that: the shell (1) is made of ceramic material, the boss (2) of the getter is made of Kovar material, and the chip Boss (3) is Kovar alloy material. 7. According to the vacuum ceramic packaging structure of the sensor according to claim 1, it is characterized in that: an exhaust pipe (6) is arranged on the said shell (1), and the outer end of the said exhaust pipe (6) is installed with Sealant (10). 8. According to the vacuum ceramic packaging structure of the sensor according to claim 1, it is characterized in that: the two sides of the said shell (1) are respectively arranged with shell pins (7), and said shell pins (7) on each side 7) Connect with the chips (5) through bonding metal wires (8) respectively.

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