TWI381492B - Method of sealing vacuum electronic device - Google Patents

Description

Sealing method of vacuum device

The present invention relates to the field of vacuum technology, and in particular, to a sealing method for a vacuum device.

Vacuum technology plays an important role in the manufacture of vacuum electronic devices, and vacuum problems are attracting more and more attention (see, Vacuum problems of miniaturization of vacuum electronic component: a new generation of compact photomultipliers, Vacuum V64, P15-31) (2002)). The quality of the sealing of vacuum devices has a significant impact on the life of the device.

Referring to FIG. 1 , in the prior art, a sealing method for a vacuum device generally includes the following steps: providing a pre-sealing device 100 including a vent hole 102; providing an exhaust pipe 110, and One end of the exhaust pipe 110 is connected to the exhaust hole 102 through the low-melting glass frit 108, and the other end is exposed outside the pre-sealing device 100; a vacuum cup 104 connected to the vacuum system 106 is provided, and the vacuum cup is provided. 104, the exhaust pipe 110 is covered, and the pre-sealing device 100 is evacuated; after the predetermined degree of vacuum is reached, a concentrating sealing device 112 is used to heat and soften the exhaust pipe 110 for sealing. When the exhaust pipe 110 is softened, a closed structure is formed at one end away from the exhaust hole 102.

Referring to FIG. 2, in the above method, the pre-sealing device 100 can be directly placed in a vacuum chamber 114, and the vacuum chamber 114 is evacuated through a vacuum system 106, and a predetermined degree of vacuum is reached in the vacuum chamber 114. After mining The electric exhaust pipe 110 is heated and softened by an electric heat sealing device 116 to perform sealing, thereby obtaining a vacuum device. When the exhaust pipe 110 is softened, a closed structure is formed at one end away from the exhaust hole 102.

However, the sealing of the pre-sealing device 100 by the above method requires the use of the exhaust pipe 110, so that a protruding tail-shaped exhaust pipe 110 is left on the packaged vacuum device, which is a vacuum device. The security and stability pose a threat. Moreover, the sealing is performed by heating and softening the exhaust pipe 110. In order to facilitate the sealing, the diameter of the exhaust pipe 110 is relatively small, generally less than 5 mm, so that exhausting through the exhaust pipe 110 is time consuming and the vacuuming time is long. Therefore, the preparation cost is also high. In addition, the exhaust pipe 110 and the gas discharged from the low-melting glass frit 108 sealing the exhaust pipe 110 during heating may enter the pre-sealing device 100, thereby affecting the vacuum degree of the vacuum device.

In view of the above, it is necessary to provide a sealing method for a vacuum device that does not require heating to soften the exhaust pipe for sealing and that can achieve faster exhaust.

A sealing method for a vacuum device, comprising the steps of: providing a pre-sealing device, the pre-sealing device comprising a casing and a venting hole disposed on the casing; providing a cover, and Forming a low-melting glass frit layer on a surface of the sealing cover; a side of the sealing cover formed with a low-melting glass frit layer corresponding to the vent hole and disposed at a distance from the vent hole; The sealing device performs vacuuming; heating and softening the low-melting glass frit layer to seal the venting opening; and cooling and solidifying, so that the sealing cover is combined with the pre-sealing device.

Sealing of the vacuum device provided by the technical solution compared with the prior art The method has the following advantages: First, the sealing cover is sealed, so that the prepared vacuum device has no protruding tail-shaped exhaust pipe, which improves the safety and stability of the vacuum device. Second, it can be exhausted through the vent hole of the large aperture, which improves the exhaust speed and saves time cost.

Hereinafter, the sealing method of the vacuum device of the present technical solution will be described in detail with reference to the accompanying drawings.

Referring to FIG. 3 and FIG. 4 , an embodiment of the present technical solution provides a sealing method for a vacuum device, which mainly includes the following steps:

In a first step, a pre-sealing device 300 is provided. The pre-sealing device 300 includes a housing 312 and a venting opening 302.

The vent 302 is disposed on the housing 312. The material of the housing 312 can be selected from any material that can be sealed by a low-melting glass frit, such as glass or metal. The size of the pre-sealing device 300 is selected according to actual conditions. The aperture of the venting opening 302 is not limited and can be opened as much as possible. However, it is selected according to the size of the pre-sealing device 300.

The pre-sealing device 300 in this embodiment is a vacuum electronic device. The housing 312 is glass, and the housing 312 is provided with a venting opening 302. The pre-sealing device 300 further includes other electronic components (not shown) disposed within the housing 312. The diameter of the vent hole 302 is preferably 2 to 10 mm. It will be appreciated that the aperture of the vent 302 is not too small or too large. Too small a pore size is not conducive to rapid venting, but too large a pore size will affect the stability after sealing.

It will be appreciated that the pre-sealing device 300 is not limited to the sealing of vacuum electronics, any device that requires permanent packaging.

In the second step, a cover 308 is provided, and a low-melting glass frit layer 304 is formed on a surface of the sealing cover 308.

The sealing cover 308 is a flat plate. The area of the sealing cover 308 is slightly larger than the area of the venting opening 302 of the pre-sealing device 300. The material of the sealing cover 308 is glass or metal, and the melting/softening temperature of the material of the sealing cover 308 should be higher than the softening temperature of the selected low melting glass frit. In this embodiment, the sealing cover 308 is a glass plate having a softening temperature higher than 600 ° C, and the softening temperature of the low-melting glass frit layer 304 is 400 ° C.

The method for forming the low-melting glass frit layer 304 on one surface of the sealing cover 308 specifically includes the following steps: First, the low-melting glass frit is mixed with a binder to obtain a slurry. Then, a low-melting glass frit layer 304 is formed on one surface of the sealing cover 308 by screen printing or manual coating. The area of the low-melting glass frit layer 304 should be slightly larger than the area of the vent hole 302, and the thickness is less than 1 mm.

Further, after forming a low-melting glass frit layer 304 on one surface of the sealing cover 308, the low-melting glass frit layer 304 is subjected to a melting treatment in a vacuum environment to discharge the internal gas. The method of melting the low-melting glass frit layer 304 in a vacuum environment specifically includes the following steps: First, the sealing cap 308 formed with the low-melting glass frit layer 304 is placed in a vacuum environment.

The sealing cover 308 is formed with the side of the low-melting glass frit layer 304 facing upward. The pressure in the vacuum environment is less than 1 x 10 ^-2 Pa. It can be understood that, in this embodiment, a plurality of low-melting glass frit layers 304 can be simultaneously smelted.

Next, the sealing cap 308 on which the low-melting glass frit layer 304 is formed is heated to keep the low-melting glass frit layer in a molten state for a certain period of time.

The heating can be achieved by a method such as electric heating wire, infrared irradiation or laser irradiation. The low-melting glass frit layer 304 is maintained in a molten state for a period of 30 to 60 minutes. In this process, all of the gas in the low-melting glass frit layer 304 is discharged.

Finally, the sealing cap 308 having the low-melting glass frit layer 304 formed is cooled to room temperature, and the molten low-melting glass frit layer 304 is solidified, and the sealing cap 308 is taken out.

In the present technical solution, since the low-melting glass frit layer 304 is subjected to smelting and exhausting treatment, the low-melting-point glass frit layer 304 is heated without gas discharge during the subsequent sealing process.

Step 3: One side of the sealing cover 308 formed with the low-melting glass frit layer 304 corresponds to the vent hole 302 and is disposed at a distance from the vent hole 302.

In this embodiment, at least three support bodies 306 may be disposed in advance around the exhaust holes 302 of the pre-sealing device 300, and the distance between the support bodies 306 is not less than 2 mm. The sealing cover 308 is placed on the support body 306, and one side of the sealing cover 308 formed with the low-melting glass frit layer 304 corresponds to the vent hole 302.

The material of the support body 306 is a low-melting glass frit, and its shape is not limited. Before the low-melting glass frit is processed into the support 306, the smelting treatment may be performed in a vacuum environment to discharge the internal gas of the low-melting glass frit. In this embodiment Three equally spaced columnar supports 306 are provided around the venting opening 302 for supporting the sealing cover 308.

The sealing cover 308 is placed on the support body 306, and one side of the low-melting glass frit layer 304 is formed in alignment with the exhaust hole 302, and the sealing cover 308 is spaced apart from the exhaust hole 302 by the support body 306. A gap is left between the supports 306, which can be used to vent.

It can be understood that, in this embodiment, the sealing cover 308 can be disposed at a distance from the vent hole 302 by other means. For example, the sealing cover 308 can be formed with a low-melting glass by a robot (not shown). One side of the powder layer 304 corresponds to the vent hole 302 and is disposed at a distance from the vent hole 302.

Further, a surface of the sealing cover 308 formed with the low-melting glass frit layer 304 may further form a getter 310 for adsorbing residual gas in the vacuum device to maintain the vacuum inside the vacuum device. The getter 310 may be an evapotranspiration getter or a non-evaporable getter. The evapotranspiration getter material is mainly composed of lanthanum, cerium, magnesium and calcium, such as lanthanum aluminum. The non-evaporable getter material mainly includes titanium, zirconium, hafnium, tantalum, vanadium, iron, aluminum, rare earth metals and alloys thereof. In this embodiment, the getter 310 is a non-evaporable getter, and the material thereof is zirconium ferrovanadium. Since the getter 310 is formed on the sealing cover 308, it is not necessary to reserve a space for the getter 310 in the pre-sealing device 300, which is advantageous for the design of the sealing device 300.

In step four, the pre-sealing device 300 is evacuated.

Vacuuming the pre-sealing device 300 can be done through a vacuum cup or vacuum chamber achieve. In this embodiment, the pre-sealing device 300 is placed in a vacuum chamber 314, and the pre-sealing device 300 is evacuated by changing the degree of vacuum of the vacuum chamber 314. Specifically, the method includes the following steps: First, a vacuum chamber 314 is provided, and the vacuum chamber 314 is in communication with an evacuation system 316, and a heating device 320 is disposed on the inner wall of the vacuum chamber 314. The heating device 320 may be a heating wire, an infrared illuminator or a laser illuminator or the like.

Next, the at least one pre-sealing device 300 is placed in a vacuum chamber 314 and evacuated.

Finally, the pre-sealing device 300 is heated to bake the pre-sealed device 300.

The pre-sealing device 300 is baked and exhausted by the heating device 320, and the air in the pre-sealing device 300 can be discharged as much as possible. The heating temperature should be lower than the softening temperature of the selected low melting glass frit. In the present embodiment, since the getter 310 is formed on the sealing cover 308, the activation of the getter 310 is completed simultaneously in the process of baking the exhaust gas.

In step five, the low-melting glass frit layer 304 is heated and softened, so that the sealing cap 308 seals the vent hole 302.

Heating can be achieved by heating device 320, or it can be directly heated by a baking oven to soften it. When the low-melting glass frit layer 304 and the support 306 are softened by heating, the sealing cap 308 is sealed by gravity to seal the vent hole 302.

Step six, cooling and solidifying, so that the sealing cover 308 and the pre-sealing device 300 are Combine.

Heating is stopped, the low melting glass frit begins to solidify, and the sealing cap 308 is sealed with the pre-sealing device 300. At this time, since the low-melting-point glass frit layer 304 is subjected to vacuum melting treatment in advance, when the low-melting-point glass frit layer 304 and the support 306 are softened by heating, no gas is discharged.

It can be understood that a weight 322 may be further disposed in advance on a surface of the sealing cover 308 where the low-melting glass frit layer 304 is not formed. After the low-melting glass frit layer 304 and the support 306 are softened, the weight 322 can give a downward pressure to the sealing cover 308, so that the sealing cover 308 can be better combined with the pre-sealing device 300.

The sealing method of the vacuum device provided by the technical solution has the following advantages: First, the non-exhaust pipe is sealed, so that the prepared vacuum device has no protruding tail-shaped exhaust pipe, thereby improving the safety and stability of the vacuum device. . Second, the exhaust through the large aperture vents increases the exhaust speed and saves time. Thirdly, the getter is formed on the sealing cover. Therefore, it is not necessary to reserve a space for setting the getter in the pre-sealing device, which is advantageous for the design of the vacuum device.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100,300‧‧‧ pre-sealed devices

102,302‧‧‧ venting holes

104‧‧‧vacuum cup

106,316‧‧‧ Vacuum system

108‧‧‧Low melting point glass powder

110‧‧‧Exhaust pipe

112‧‧‧Concentrating sealing device

114,314‧‧‧vacuum room

116‧‧‧Electric heat sealing device

304‧‧‧Low-melting glass powder layer

306‧‧‧Support

308‧‧‧Filling cover

310‧‧‧ getter

312‧‧‧Shell

320‧‧‧ heating device

322‧‧‧ Heavy objects

1 is a structure of a device for sealing a vacuum device using a vacuum cup in the prior art. schematic diagram.

2 is a schematic view showing the structure of a device for sealing a vacuum device using a vacuum chamber in the prior art.

FIG. 3 is a flow chart of a sealing method of a vacuum device according to an embodiment of the present technical solution.

4 is a schematic structural view of an apparatus for sealing a vacuum device according to an embodiment of the present technical solution.

Claims (11)

A sealing method for a vacuum device, comprising the steps of: providing a pre-sealing device, the pre-sealing device comprising a casing and a venting hole disposed on the casing; providing a cover, and Forming a low-melting glass frit layer on a surface of the sealing cover, and melting the low-melting glass frit layer in a vacuum environment; and forming one side of the sealing cap with a low-melting glass frit layer corresponding to the vent hole; And is disposed at a distance from the vent hole; vacuuming the pre-sealing device; heating and softening the low-melting glass powder layer, and sealing the sealing hole; and cooling and solidifying, so that the sealing cover is Pre-sealed device bonding. The sealing method of the vacuum device according to claim 1, wherein the material of the pre-sealing device is glass or metal. The sealing method of the vacuum device according to claim 1, wherein the vent hole has a pore diameter of 2 to 10 mm. The sealing method of the vacuum device according to claim 1, wherein the sealing cover is made of metal or glass, and the sealing cap has a melting point/softening temperature higher than the selected low melting glass powder. Softening temperature. The method of sealing a vacuum device according to claim 1, wherein the low-melting glass frit layer is formed on a surface of the sealing cover by screen printing or manual coating. The sealing method of the vacuum device according to claim 1, wherein the process of melting the low-melting glass frit layer in a vacuum environment specifically comprises the step of: forming a seal having a low-melting glass frit layer The cover is placed in a vacuum environment with a pressure lower than 1×10 ⁻² Pa; the sealing cover forming the low-melting glass frit layer is heated to keep the low-melting glass frit layer in a molten state and kept at 30~ 60 minutes; the sealing cap formed with the low-melting glass frit layer was cooled to room temperature, and the molten low-melting glass frit layer was solidified, and the sealing cap was taken out. The method of sealing a vacuum device according to claim 6, wherein the low-melting glass frit layer is further melted in a vacuum environment, and further formed on a surface of the sealing cap formed with a low-melting glass frit layer. A getter. The sealing method of the vacuum device according to claim 1, wherein at least three support bodies are disposed around the vent hole of the pre-sealing device, and the sealing cover is placed on the support body and formed One side of the low-melting glass frit layer corresponds to the vent hole, and the sealing cover is spaced apart from the vent hole by the support body. The method for sealing a vacuum device according to claim 8, wherein the material of the support is a low-melting glass frit, and the low-melting glass frit is melted before being processed into a support. deal with. The sealing method of the vacuum device according to claim 9, wherein the support is softened by heating, and the sealing cover seals the vent hole by gravity. The method of sealing a vacuum device according to claim 1, wherein the vacuuming the pre-sealing device comprises the steps of: providing a vacuum chamber, the vacuum chamber being connected to a vacuum system And the heating chamber is provided with a heating device; the pre-sealing device is placed in the vacuum chamber, and vacuuming is performed; and the pre-sealing device is heated to bake and exhaust the pre-sealing device.