JPS5979553A - Method and device for forming airtight seal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on U.S. patent application Ser.
．． Regarding issue 6. Reference is made herein to the above-mentioned application.

The present invention relates generally to sealing processes and apparatus N for sealing processes, and more particularly to electronic components and! The present invention relates to an improved method and apparatus for forming a hermetic seal between a cage and a cage cover.

Many circuits and components are housed in sealed cages to protect them from damage that may result from exposure to the surrounding environment. +11 Metal sealed like solder 1j!I
: +21 ceramic or various types of glass; and (3)
There are organic sealants such as epoxy resins. Among these, organic sealants can pass through multi-needle substances in a relatively short period of time (for example, a few days) when compared to the lifespan of the circuit housed in the package, ensuring that they form a hermetic seal. Only the first two, ie, m +21. When a sealant becomes permeable to water vapor, for example, chemical reactions occur within the package with certain ions such as chlorine, sodium, and potassium, creating corrosion deposits that can damage wiring and electronic components. Facilitates damage to the circuits packaged with it. Using several gold-dust alloys as sealants, variable results have been produced.One of the highly desirable properties of the 6@'lA sealant is its ability to withstand high temperatures. For example, ordinary lead-tin solder provides a satisfactory seal at temperatures up to 125°C. At higher temperatures, e.g. 150°C, an alloy of 80% gold and 20% tin is desirable; Unfortunately, the melting point of this alloy is around 2800, which means that during the sealing process, melting of the material can lead to undesirable heating of the electronic components contained within the cage, as well as parameter shifts and circuitry within the arm cage. This may result in premature failure of the product.

The risk to circuits or devices due to high sealing temperatures becomes even more serious when glass-metal sealants are used since such sealants have melting temperatures of 400° C. or higher. Although vitreous sealants are much less expensive than the gold-soot alloys mentioned above, the use of such vitreous sealants is advantageous due to their ``high melting temperature'' when heating of parts is a concern. excluded by.

・! Methods such as impulse welding, or impact welding, using either fixed electrodes or rolling welds have been developed to seal flat cages without excessively heating the contents of the cage. These techniques require a metal cover and a metal base cage or, at a minimum, a full metal sealing surface on both the cover and the i4 cage. Unfortunately, the equipment required to perform such welding techniques is expensive and requires specialized tools for the size of the P1/'P cage. Furthermore, the metal cage itself is relatively expensive.

The term "hot capping" refers to the process of sealing metal or ceramic covers and i4 cages using a metal sealant. If either the cover or the cage is ceramic, the ceramic member must have a metal sealing surface fused thereto. The seal is formed by applying an electrically heated surface to the cover. However, since the cover must be heated to at least the sealing temperature, the electronic components
Or the temperature of the electronic circuit will rise.

Since ceramic neck cages are less expensive than metal arm cages, and glass sealing materials are less expensive than metal-based sealants, the most economical solution for hermetic seals and base cages is Ceramic packages and covers would be used to seal with these all-vitreous sealants without the need for polymerized metal sealing layers.

No. 298,786, cited above, discloses an improved method and apparatus for hermetically sealing ceramic or metal packages containing electronic circuits. Accordingly, a heater preform for sealing the flat cage to the package cover is positioned between the sealing surfaces of the cage and the cover. The heater preform has surface resistance and shape corresponding to the area and shape of the sealing surface. Additionally, the playform has first and second electrical contact areas.

A vitreous sealing material is applied between the sealing surface and the preform. The heater preform is electrically heated to a predetermined temperature to form a debris seal between the sealing surfaces of the ram cage and the cover with the sealing material and the preform.

Although the process disclosed in the above-mentioned U.S. IYQ patent application Ser. There still exists a need to provide an even more effective process for forming an air seal between a base cage and a base cage cover at lower temperatures.

It is an object of the present invention to provide an improved and cost effective method and apparatus for sealing electronic circuits.

It is another object of the present invention to provide an improved device for hermetically sealing a ceramic cover to a ceramic package using a vitreous sealant without excessively heating the electronic components or circuits within the package. How and how? 5.

Another object of the present invention is to provide an improved method and apparatus for hermetically sealing a ceramic cover to a ceramic cage without requiring a metal sealing layer on the ceramic component.

Another object of the present invention is to provide an improved method and apparatus for hermetically sealing a ceramic cover to a ceramic cage, for facilitating the cracking of electronic components housed within the flat cage. An object of the present invention is to provide an improved method and apparatus for intentionally breaking a hermetic seal.

Another object of the invention is to provide an improved means for hermetically sealing a ceramic cover to a ceramic cage without having to worry about positioning a metal preform between the sealing surfaces of the cover and the package. An object of the present invention is to provide a method and a device.

Accordingly, the above and other objects are achieved by a method of forming a seal between a sealed region of a first body and a sealed region of a second body, the method comprising: a step of gluing the first main body to the head of the second main body; a step of applying a sealing material between the sealing area of the second main body and the heater IA bonded to the first main body; aligning the sealing area with the sealing area of the first body; bringing the second body into contact with the whistle 1; passing an electric current through the layer of the heater of conductive material; activated to,
forming a seal between the first body and the second body.

Fourth, in one device for forming a seal between the sealing area of the first body and the sealing area of the second body, one layer of the heater of J4 electrical material is adhered to one of the sealing surfaces. An apparatus is fully disclosed.

The device includes a stand for mounting and supporting the first body;
Controls the second main body, a holding member that moves, aligns, and holds the entire second body, an electronic side l and a stand for allowing current to flow through the conductive material heater layer, a holding member, and a by-product of the device β. Consists of equipment.

The above objects, features and advantages of the present invention will be better understood from the following detailed description taken in conjunction with the accompanying drawings.

Referring to FIG. 1, an electronic component package is generally designated by the numeral 10. The exploded view of FIG. 1 shows the monolithic package 2 and the cage cover 14 which hermetically seals the cavity base 16. A plurality of bins 18 are connected to a contact portion 19 positioned on the cavity base 16 . Electronic components can be mounted on the base 16 and connected to the contacts 19. The heater layer 20 made of a conductive material is
The surface of the package 12 is contacted in a sealed area between the package 12 and the cover 14. The heater layer 420 includes a plurality of adhesive portions 22 . Still referring to FIG. 2, the package cover 14 is covered with a sealing material over the surface of the sealing area that corresponds to the shape of the heater layer 2o bonded to the cage 12.

11th. NoJ shown in A? The cage 12 is made of ceramic. The heater layer 20 comprises a thick film type powder, paste, or liquid that is applied or screen printed onto the sealing surface of the /4' gauge 12 according to known thick film techniques. The end-of-life pattern of the heater layer 20 will be described in detail below with reference to FIG. 4. The heater layer 2o can be heated using methods such as baking or adding a catalyst.
Glue the sealing surface of the cage 12. The sealing material 24 may be an organic, ceramic, glass, or metallic material and must be thermally responsive.

・I of the cover 14 to apply 240 layers of sealing material to form an airtight seal between the naso cage 12 and the cover 4.
The QJ structure is aligned with a heater layer 20 of conductive material adhered to the sealing surface of the nozzle 12. Next, put the cover on and put the sealing material 24 on.
is brought into contact with the heater layer 2o.

A current is then induced in any manner to flow through the heater layer.

The acid is also easy to do.Introduce the electrode directly into the metal heater layer 20 by attaching the electrode to the contact g (122).As a variant, if the heater layer 20 is made of a material that can be dielectrically heated, the current can be alternately applied. Furthermore, if the heater layer 20 consists of one or more closed loops, the current can be induced by magnetic induction. Regardless of the means used, the sealing material 24'' will be cured, fused, mated, or otherwise bonded to the heater layer 20.

Referring to FIG. 3, an embodiment of the present invention is shown that reduces heat transfer to the cavity base 16 and speeds the sealing process between the heater 520 and the sealing material 24. In order to reduce heat flow into the cavity base 16 and thereby reduce undesirable changes in the properties of the electronic components attached to the cavity base 16, the pine cage 12 is comprised of at least two different types of ceramics. .・! The top portion 26 of the cage 120 is comprised of a ceramic material with relatively low thermal conductivity, such as steatite. The bottom portion 28 of package 12 is comprised of a relatively high thermal conductivity ceramic material, such as aluminum oxide. Top portion 26 and bottom portion 28 are bonded together with a suitable adhesive during manufacturing.

The unique structure of FIG. 3 produces two effects. 1st
Additionally, since the top portion 26 of the /41 package 12 has a low thermal conductivity, the heater 7420 can operate the sealing process more efficiently when heat is directed toward the package cover 12. , Second, the heat generated by the electronic components attached to the cavity base 16 is
It is directed to the lower part 28 because it has a high thermal conductivity.

)! In addition to providing composite portions 26, 28 for the cage 12, FIG. hardened heater tcj
A protective layer 30 of non-conductive material is shown applied over 20. The protective layer 3o improves the contact between the sealing material 24 of the package cover 14 and the heater layer 20 of the package 12. As a result, heat is transferred to the heater layer 20. b. are efficiently transmitted to the sealing material 24 through the protective layer 3o. In addition to completing the sealing process in a shorter time, burn-out of the heater layer 20 is greatly reduced, reducing the conduction of heat to the cavity base 16.

FIG. 4 shows an enlarged view of the heater t4 turn 2o, with the shaded area representing the conductive material. Region 32 of the junction between the contact portion 22 of the conductive path and the heater layer 20
are made narrower than all other areas except the corners 34. The narrow conductive path in the bonding area 32 of the contact area 22 causes a concentration of heat in the bonding area 32 . The concentration of heat in region 32 is needed to compensate for the tendency for heat to flow from heater layer 20 to colder polar contact 22 . Similarly, corner 3
The narrow conductive path located at 4 causes a concentration of heat at corner 34. The heat concentration in the corner 34 is needed to compensate for the large cross-sectional area of the corner 34 and to provide the heat necessary to melt more of the sealing material 24 covering the added cross-sectional area of the corner 34.

Thus, the heater turn 20 shown in FIG. 4 concentrates heat in areas where it would conventionally take longer to complete a seal. The result is an improved thick film Heatano! The turns 20 help direct heat more efficiently to locations with larger sealed volumes, thereby reducing the overall time required to perform the seal.・J? in Figure 4? 〉-n is functionally similar to ! The use of a heater layer with turns is not always 8-square.

However, two layers of heaters with such a pattern
0 helps minimize the amount of conductive material required to form the heater layer 20, which is dependent on the size of the package or cover 14 and the type of conductive material employed. This results in significant cost savings. Dimensions. Such a pattern increases the resistance of the heater layer 20 to achieve higher heating voltages at lower currents. Furthermore, when the adhesion between the heater 1 forging 20 and the sealing material 24 is weaker than the adhesion between the sealing material 24 and the cover 12 or the cover 14, a heater having an /f turn as shown in FIG. By using 20 layers, the pattern of multiple empty i+
J236 produces stronger adhesion. As a result, the sealing material 24 not only adheres to the heater layer 20, but also to the package 12 or cover 14 through the void 36.

FIG. 5 shows a lead frame electronic component package 12,
and an enlarged view of the top contact nine-cage cover 14. Package 12 consists of three distinct parts.

Top portion 38 is made of a ceramic material with relatively low thermal conductivity. The lower portion 40 is made of a ceramic material that has a relatively high thermal conductivity compared to the top portion 38. The middle section 42 is a layer of sealed glass in which a plurality of bottles are embedded. Package 1 in Figure 5
2 functions in a thermally similar manner to the .9 cage of FIG. Since the top portion 38 is thermally non-conductive, it does not conduct heat resulting from the sealing process to the cavity base 16.

In contrast, heat generated by circuitry operating within cavity 16 is conducted throughout package bin 18 and bottom portion 42 due to the relatively high thermal conductivity of the bottom portion.

The package cover 14 is made of ceramic material υ, and the ceramic material may be of a type with high thermal conductivity or of a type with low thermal conductivity. A plurality of top electrode contact portions 44 and side heater layer contact portions 46 are adhered to the package cover 14 . Both contacts 44,46 are made of a material similar to that used in the heater layer 2o and are similarly bonded to the cage force bar 14. /IP cage cover 14
Below.

11, the heater layer 48 is adhered to the product sealing area associated with the sealing area 54 of the package 12.

A layer 50 of sealing material is then applied to the heater layer 48. Optionally, a layer of sealing material is packaged in the sealing area 54 of [2].
can be attached to.

To form a seal, the pin cage force bar 14 is aligned over the sealing vertical area 54 of the pin cage 12.

Next, cover 14! contact the cage 12.

The sealing material is activated by contacting the electrode contact i';B 44, which is connected to the heater layer 48 by the heater layer contact 46.

arr 61gl iC&Y, rose'i-shi56 and U cover 58 complete pack-ftsuk-cine1
An exploded view of the i-structure is shown.

Cover 58 is similar to cover 1 in FIGS. 1, 2, and 5.
It is easy to see that it is relatively larger than 4.

Furthermore, a relatively large hybrid circuit 59 and four electric circuits 60
and is attached to a nine-piece cage 56.

A plurality of bins 62 are directly connected to conductive path 60 by bin heads 70 .

Package cover 58i-1: Since it is large enough to be required for the large circuit section 59, it becomes very difficult to form a contact section on the surface of the mother package 560. As a result, a contact portion 68 for the heater layer 64 is created on the side of the cover 58. The heater layer 64 is formed in the same manner as the heater layer 1 described with reference to FIG. Tsu cage cover 5
Glue it on the bottom part of 8.

Similarly, a layer of sealing material 66 may be applied over the sealed area of the package 56 or optionally over the heater layer 64. - A seal between the two cages 56 and the cover 58 is formed by inducing a current to flow through the heater layer 64 and adhering the sealing layer to both the heater layer 64 and the bag cage 56.

It is important to recognize that the package cover can be made such that the heater/J 64 breaks the head 70 of the bottle 62 while contacting the cage cover 58 by side heater contacts 68. . This special MrU embodiment is shown in FIG. 9 and requires only a few modifications to the embodiment shown in FIG.

7-9 illustrate a pair of electrodes 72 that contact the mother cage and package cover combination referenced in FIGS. 1, 5, and 6.

In FIG. 7, electrode 72 contacts heater layer 20 at heater j-contact 22 adhered to the surface of monolithic package 2. In FIG. In FIG. 8, the top part of the cage force bar 14 is shown at 96
The electrode 72 is connected to the heater layer 48 by contacting the electrode contact 44 adhered to the top portion of the package cover 14 . Figure 9 shows the 6th
The modification implementation of all the packs explained with reference to the figure is shown by @. Grooves (not shown) are disposed along the underside of the package cover 58 to accommodate the heads 70 of the plurality of pins 62. Additionally, electrodes 72 contact heater layer contacts 68 on the sides of package cover 58.

FIG. 10 shows an apparatus for forming a seal between the cage and the package cover. The device is generally designated No. 4 74 and is particularly adapted to the combination of a top contact, two-cage, and base-cage force bar as shown in FIGS. 7 and 8. The device 74 is no! It consists of a stand 76 for mounting and supporting the cage 84, a plurality of electrode assemblies 78, and a presser assembly 80. device 74
to mechanical, electrical, hydraulic, or pneumatic actuation devices;
Connected by a shaft 82, the actuation surface raises or lowers the electrode assembly 78 and the hold-down assembly 80 to simultaneously contact the pancage.

Still referring to FIG. 11, electrode 72 is snapped into electrode mount 86 and held in place by assembly screw 88. The opposing throat of electrode mount 86 is threaded and receives a lug 90, washer 92, and nut 94. '7M, m96 is assigned to Lug90. 711. To control the temperature of the poles 72 and the electrode fitting 86, a liquid or gas is introduced through the inlet 98, passed through the cooling chamber 100, and released from the outlet 102.The electrode fitting 86 is connected to a spring-loaded chamber. 104, the spring loaded chamber consists of a body 106, a cap 08, and a spring 110 retained within the chamber. Pin 112t-) Place it on the rack 114 and
, prevent rotation of the pole mounting body. The contact area between the main body 106 and the cap 08 and the electrode mounting body 86 has a
0, a space 116 is left, and the H1 pole mounting hole 86 is slightly tilted so that the plane of the electrode contact surface 73 can be aligned with the plane of the heating contact part 22. The chamber 104, which has lost its spring load, is unable to compensate for the undesirable movement and applies uniform pressure to the heating contact portion 22, causing it to thermally expand. The top contact electrode structure shown in FIG. 5 is useful for sealing corrugations or chip carriers where there is no space in the cage 12 for an electrode contact area.

Still referring to FIG. 12, the presser foot assembly includes a spring-loaded chamber 10 similar to that described above with reference to FIG.
It consists of a presser main body 118 attached to 4. The presser foot assembly 118 consists of a vacuum tube 7'' 120 connected to a vacuum inlet 112 and a vacuum outlet 124. Presser foot ii
126 serves to hold the package cover 14.

The device for controlling the temperature of the presser foot main body 118 is a gas,
or a liquid inlet 98, a cooling chamber 110, and an outlet 102, the device functions similarly to the cooling device described above with reference to FIG.

Also shown in FIGS. 13a and 13b is a stand 76. For purposes of illustration, pedestal 76 is shown supporting a side contact package such as that referenced in FIG. 6, as opposed to the top contact package shown in FIG. Hold down the package cover 58 and hold the assembly 80 (first
3a or 13b) on top of the cage 56. The package 56 is mounted on the plywood 128 and the plywood 128 is mounted on the table base 130. There is a cooling chamber 132 in the table base 130, and an inlet 98
The gas or liquid flowing from the cooling chamber 132 flows to the outlet 102 through the entire cooling chamber 132. Is the base plate 128 iJ? It can be seen that the cage 56 is picked up and raised to project the package 56 above the plywood 130 and provide the proper thermal gradient to facilitate the gluing process. The spring load of the table base 130 is the table alignment bin 1
38 into the base [30].

Alignment bin 138 presses on a number of springs 140 associated therewith. Spring 140 is held in spring base 142.

Referring again to FIG. 10, the top contact i4 cage 84
The package 84 is moved to and attached to the platform 130 to form a seal between the package cover 85 and the package cover 85 . Place the cover 85 on VjM of the presser assembly 80, move it to the grip cage 84, and align it. The electrode 72 contacts the heater no contact portion 22, and the no! The pole assembly 78 and presser assembly 80 are completely lowered until the cage cover 85 contacts the cage 84. The springs of chamber 104 and base 142 provide a constant force to keep cover 85 in contact with package 84 while compensating for thermal expansion.

Sealed! By reheating the two cages 84 and the cover 85, the seals are broken and the electronic components housed within the two cages can be repaired or replaced. In order to seal, it is best to use a new cover and apply a new layer of sealing material.

The above description is given by way of example only.

Changes in form and detail may be made by those skilled in the art without departing from the scope of the invention as claimed. For example, as shown in FIGS. 10, 13a, and 13b, the platform 76 shown in FIG.
Spring 140 shown on the stand in Figures 15a and 13b is flexible and is thus bondable. 9. In such a configuration, the hold-down assembly 80 of FIG.
(see Figures 1 and 1'5b) downwardly, and the cover 58 pushes the cage 56 downwardly. As a result, the spring-loaded platform 76 of FIGS. 138 and 13b is depressed, exerting an upward force that opposes the force of the hold-down assembly 80. '[The pressure at pole 72 (see Figure 10) is
8 (see Figures 13a and 13b) laterally from both sides to firmly clamp the force I in place. 17. When a flow is applied to one layer of the heater, the sealing glass softens and the spring-loaded platform 76...! Push the cage 56 up toward -58.

[Brief explanation of the drawing]

FIG. 1 is an exploded view of a monolithic electronic component package, which has nine heater turns on the surface of the cage to form an airtight seal on the underside of the package cover. 2 is a perspective view of the underside of the package cover of FIG. 1, which has a sealing layer on its lower surface portion corresponding to the heater layer of the monolithic package of FIG. 1; FIG. Figure 3 shows how to minimize heating of electronic components and ensure hermetic sealing.
! FIG. 2 is a perspective view of a monolithic/4' cage structure formed in a two cage cover. FIG. 4 is a partially enlarged view of an exemplary nine-turn heater. FIG. 5 is an exploded view of a frame N-child component package forming a hermetic seal to the top contact nine cage cover in accordance with the present invention. FIG. 6 is an exploded view of a full back electronics package forming a hermetic seal to the side contact package cover in accordance with the present invention. FIG. 7 is a perspective view of the electrodes in contact with the heater pattern used in the monolithic package of FIG. 8 is a perspective view of an electrode in contact with a heater pattern used in the lead frame package of FIG. 5. FIG. FIG. 9 is a perspective view of the electrodes in contact with the heater pattern used in the standard full-pack/arm cage hairstyle embodiment of FIG. 6; FIG. 10 shows the holding of the heater turn of the electronic component package to form a hermetic seal between the electronic component package and the corresponding cover according to the present invention;
FIG. 3 is a front view of the device contacting the turn; FIG. 11 is a cross-sectional view of an electrode assembly for use with the apparatus of FIG. 10. FIG. 12 is a cross-sectional view of a presser foot assembly for use with the apparatus of FIG. 10; Figures 1.5a and 13b are front views, one wound view, of a spring-loaded white assembly for use with the apparatus of Figure 10; 10...Electronic parts and cages, 12...Monolithic parts and cages, ]6...Cavity base, 14.
...Package cover, 18...Pin, 19...Contact part, 20...Heater layer, 22...Contact part, 24
... Sealing material, 26 ... Top part of package, 28
...Bottom part, 30...Protective layer, 34...Corner, 38
. . . top portion, 40 . . . lower portion, 42 . . . middle portion, 44 . . . ... sealed head mount, 50... sealing material, 56... pine cage, 5
8...Cover, 59...Hybrid circuit, 60.
...Conducting path, 62...Bin, 70...Bin head,
64... Heater single layer, 66... Sealing material, 72...
・1ヱpole, 68...Heater contact part, 74...device, 84...NoJ? Tsukei, 76... units, 78...
... Electrode assembly, 80 ... Presser assembly, 82 ... Shaft, 86 ... Senpoku mounting body, 88 ... Assembly screw, 90 ...
...Lug, 92...Washer, 94...Nut,
96...Electric wire, 98...Population, 100...Cooling chamber, 102...Outlet, 104...Spring loaded chamber,
106...Body, 108...Cap, 110...
・il: l, 112... pin, 114... track, 116... space, 73... electrode contact surface, 11
8...Presser body, 124...Vacuum outlet, 120...
・Vacuum chew! , 126... Pressing surface, 128... Base plate, 130... Base base, 132... Cooling chamber, 138
...Base alignment pin, 140...Spring, 85...Cover invitation 11 Figure 12 Figure 1, Indication of the incident Patent Application No. 106576 of 1981 2, Claim for invention Method and device for forming an airtight seal 3
, Relationship with the person making the amendment 4th month 1st year Applicant 4, Agent 5, Lottery of amendment order September 27, 1972 6,
Target of amendment All drawings 7, contents of amendment

Claims (1)

[Scope of Claims] (1) A method of forming an airtight seal between an electronic component package and a package cover, comprising: (a) adhering a heater made of conductive material to a sealed area of the package; (b) sealing material; between the heater layer and the sealed area of the cover, (c) align the sealed area of the cover with the sealed area of the cage, and (c+) q@ the aligned cover with the sealed area of the cage. (e) inducing an electric current to flow through the heater layer; and sealing material f: thermally activated to form a hermetic seal between the package and the cover. How to form. +21 'fL (, In a device for forming an airtight seal between a sealed area of a child component package and a sealed area of a package cover, (a) - a stand device for attaching and supporting the grip cage; and (b) -4 screws. (C) an electrode device that electrically contacts the conductive heater layer; (d) a device that induces a current to flow from the 'electrode to the conductive heater layer. A device for forming an airtight seal characterized by: (3) In an electronic component package, a support device a that supports an electronic circuit portion; a conductive layer device which is placed between the support device and the cover device, the conductive layer device being capable of heating a localized heating element by applying an electric current to the conductive layer device; and forming a hermetic seal between the support device and the cover device.