JPH06286148A - Bonding method for ink jet printing head - Google Patents

Abstract

PURPOSE:To obtain a bonding part superior in corrosion resistance without giving a large thermal damage to an object to be bonded by a method wherein three-ply metallized layers of Au, Sn, and Au are disposed on the surfaces of two alloy members forming a head, both the alloy members are made to adhere to each other with the metallized layers in between, and the metallized layers are melted. CONSTITUTION:A plurality of alloy members 101, 111 form an ink jet printing head. When the first surface of the first alloy member 101 is bonded to the second surface of the second alloy member 111, three-ply metallized layers of Au as first metallized plies 103, 107, Sn as second metallized plies 104, 108, and Au as third metallized plies 105, 109 are provided in this order from the matrixes on at least one of the first and second surfaces. The first surface is disposed opposedly to the second surface. After the relative position of the first surface and the second surface is adjusted, the both are made to adhere to each other. The three-ply metallized layers are heated to a temperature of 553 deg.K or higher to be melted without melting both the members 101, 111 to bond both the alloy members.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining ink jet print heads, which joins alloy members constituting an ink jet print head.

[0002]

2. Description of the Related Art In an ink jet print head, in order to form a fine three-dimensional ink flow path, metal plates on which a fine two-dimensional pattern is formed are laminated and joined by using a technique such as etching or electroforming. It is necessary, and soldering and brazing are often used. Incidentally, Japanese Patent Laid-Open No. 2-1
07451 and Japanese Unexamined Patent Publication (Kokai) No. 3-142248 A
A method of brazing and soldering using a u-Ni-based alloy and a Pb-Sn-based alloy is disclosed. Conventionally, in this type of solder joining and brazing, the solder or brazing material layer is formed as a single layer by plating or vapor deposition.

[0003]

The inks used in ink jet printers are often corrosive, and the components and joints are required to have corrosion resistance to the inks. In the above-mentioned conventional technique, in the case of brazing using a Ni-Au alloy, there is a problem that the corrosion resistance of the joint is high but the joint temperature is high and the thermal damage to the objects to be joined is large. Further, in the case of soldering using a Pb-Sn alloy, there is a problem that the joining temperature is low but the corrosion resistance is low.

An object of the present invention is to provide a joining method and joining apparatus for an ink jet print head which can obtain a joined portion having excellent corrosion resistance without causing a large thermal damage to the article to be joined.

[0005]

In order to achieve the above object, the present invention uses a metallized layer having a three-layer structure in which Sn is sandwiched with Au as a bonding layer. The technique of forming the bonding layer of the Au—Sn alloy as a single alloy layer on the bonding surface has not been established, and it is extremely difficult to control the composition of the bonding layer with high accuracy, and it is not practical. Au-Sn
The method of inserting the alloy foil into the joint is not practical because the Au—Sn alloy is extremely brittle and difficult to machine.

In the present invention, the Sn content is 20 in the order of Au as the first metallization layer, Sn as the second metallization layer, and Au as the third metallization layer from the alloy member side.
The metallized layers (hereinafter referred to as bonding layers) having a total thickness of 3 μm or more in which the respective thicknesses are adjusted so as to be more than mass% and less than 40 mass% are formed, and the bonding surface is activated by an Ar beam. After being converted, the materials are aligned and brought into close contact in the atmosphere, and then heated in vacuum or in an inert gas.

Further, while adjusting the thicknesses of the first, second and third metallized layers so that the Sn content in the entire bonding layer is more than 20 mass% and less than 40 mass%, the thickness of the first metallized layer is 1 μm. As described above, the joining layer having a total thickness of 3 μm or more is formed on the first and second surfaces of the alloy member and is used for joining.

Further, while adjusting the thicknesses of the first, second and third metallized layers so that the Sn content in the entire bonding layer is more than 20 mass% and less than 40 mass%, the first metallized layer and the third metallized layer are adjusted. And the same thickness, and a bonding layer having a total thickness of 3 μm or more is formed on one of the first and second surfaces of the alloy member and is used for bonding.

Further, in heating, after the joining surfaces are aligned, before heating in a vacuum or in an inert gas, resistance welding or mechanical fastening is used to preliminarily determine a fixed object to be joined. A jig which is heated and held at a temperature is pressed to heat it, and after the object to be bonded reaches a predetermined temperature, an inert gas is blown onto the object to be cooled to cool it.

[0010]

In the bonding layer consisting of three metallized layers of Au, Sn and Au, Sn is melted by heating to 553K or higher during bonding heating and interdiffuses with Au to form a melt layer of Au-Sn alloy. To do. At this time, Sn diffuses into the alloy member to form a compound, so that the Sn concentration in the bonding layer is reduced and the melting point of the bonding layer is changed. 3 according to the invention
According to the bonding layer made of the layer metallized layer, Au serves as a barrier layer against the diffusion of Sn and suppresses the compound formation between the alloy member and Sn. Due to this action, the change in Sn concentration in the bonding layer can be suppressed low, and as a result, the change in melting point of the bonding layer can also be suppressed low. According to the present invention, by making the thickness of Au as the first metallization layer 1 μm or more, it is possible to sufficiently suppress the Sn concentration change due to diffusion.
When the thickness of Au as the first metallized layer is less than 1 μm, Au diffuses within a short time due to diffusion of Sn and Au.
Melts and loses its function as a barrier layer.

In the bonding layer having an Sn content of 20 mass% Sn or less, the melting point of the bonding layer remarkably rises due to the decrease in the Sn concentration in the bonding layer due to the compound formation during the heat bonding as described above. As a result, the solder is solidified before sufficient melt is generated at the joint, resulting in incomplete adhesion of the joint. However, when the bonding layer having an Sn content of more than 20 mass% and less than 40 mass% according to the present invention is used, the Sn concentration in the bonding layer due to the compound formation during the heating bonding is decreased, and the melting temperature of the bonding layer is decreased. A sufficient melt is generated in the part to improve the adhesion of the joint part.

By irradiating the bonding surface with an Ar beam in a vacuum, oils and fats, water, and oxide films adhering to the bonding surface are removed. As a result, the bonding surface becomes an active surface having a high bonding property, and the bonding property is improved. The alignment in the atmosphere is easier than the alignment in vacuum, and the time required for the alignment can be shortened. By heating and pressurizing in a vacuum or in an inert gas, the activated bonding surface is not re-contaminated, so that the bonding property is improved. After aligning the joint surfaces and fixing the objects to be joined using spot welding or mechanical fastening before heating and pressurizing in vacuum or in inert gas,
The position shift during joining does not occur, and the yield and work efficiency can be improved. By pressing a jig that has been heated and maintained at a predetermined temperature against the object to be bonded and applying heat and pressure, and after the object to be bonded reaches a predetermined temperature, an inert gas is blown onto the object to be cooled to obtain a compound. It is possible to improve the bonding strength by suppressing the formation of.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the joining method of the present invention will be described below with reference to FIGS. 1, 2 and 3.

First, a method of forming a metallized layer on an alloy member will be described with reference to FIG. 101 is S having a thickness of 50 μm
US304 first alloy member, 102 is 1 μm thick Ni
A metallization layer, 103 is a first metallization layer made of Au having a thickness of 2.0 μm, 104 is a second metallization layer made of Sn having a thickness of 1.8 μm, and 105 is Au having a thickness of 0.3 μm.
Is a third metallization layer made of Au, 107 is a first metallization layer made of Au having a thickness of 2.0 μm, and 108 is a thickness of 1.8 μm.
The second metallization layer 109 made of Sn of 109 has a thickness of 0.
A third metallization layer made of Au having a thickness of 3 μm, and 111 is a second alloy member made of Ni and having a thickness of 27 μm.

The first alloy member 101 made of SUS304 is electrolessly plated with Ni—P having a thickness of 1 μm by wet plating. The thickness does not necessarily have to be 1 μm, but it is necessary that the Ni is not completely consumed as a compound with Sn after bonding. Ni-Sn compound is SUS3
If the bonding property with 04 is poor and all of Ni is consumed as a compound with Sn after bonding, the bonding strength will be extremely lowered. Next, as the first metallized layer 103, a thickness of 2.0
μm Au is formed by wet plating. Next, as the second metallized layer 104, Sn having a thickness of 1.8 μm is formed by wet plating. Further, Au having a thickness of 0.3 μm is formed by wet plating as the third metallized layer 105.

The Ni second alloy member 111 is manufactured by electroforming. Since the electroformed Ni has good bondability with the Au-Sn alloy, it is not necessary to apply Ni metallization to the bonding surface, and the thickness of the first metallized layer 107 is 2.0 μm directly.
m of Au is formed by wet plating. Next, Sn having a thickness of 1.8 μm is formed as a second metallization layer 108 by wet plating. Further, Au having a thickness of 0.3 μm is formed by wet plating as the third metallized layer 109. In the present invention, the metallized layers are all formed by wet plating, but the same effect can be obtained by forming all or part of the metallized layers by another film forming means such as vacuum deposition or sputtering. .

Next, with respect to the change in the microstructure of the joint due to the joining,
It will be described with reference to FIGS. 2 and 3. FIG. 2 is a diagram showing the structure of the joint portion in each process of bonding, and FIG. 3 is a diagram showing the structure and melting point of the bonding layer in each process of bonding.

Reference numeral 101 denotes a 50 μm thick SUS304 first alloy member, and 102 denotes a 1 μm thick N on the first alloy member side.
i metallized layer, 103 has a thickness of 2.0 on the first alloy member side
The first metallization layer made of Au having a thickness of 104 μm, the second metallization layer 104 made of Sn having a thickness of 1.8 μm on the first alloy member side, and the Au having a thickness of 0.3 μm on the first alloy member side.
A third metallized layer 106 made of Ni, a Ni-Sn intermetallic compound on the first alloy member side, a first metallized layer 107 made of Au having a thickness of 2.0 μm on the second alloy member side,
Is a second alloy made of Sn having a thickness of 1.8 μm on the second alloy member side.
The metallization layer 109 is 0.3 μm thick on the second alloy member side.
m is a third metallization layer made of Au, 110 is a Ni—Sn intermetallic compound on the second alloy member side, and 111 is a thickness of 27 μm.
m second Ni alloy member, 130 is Au—Sn combined financial liquid.

The structure of the joint in each step of joining is as follows. A case where the heating rate of heating the joint is as high as 20 K / s will be described.

(1) State A The state A is the state in which the first alloy member 101 and the second alloy member 111 are in close contact with each other with the joining layer interposed therebetween. In this state, all layers are solid.

(2) State B State B is the state in which the state A is heated to just above the melting point of Sn. The second metallization layer 104 made of Sn having a thickness of 1.8 μm on the first alloy member side and the thickness on the second alloy member side 1.
The second metallization layer 108 made of 8 μm Sn melts.

(3) Between states B and C If the heating is further continued, the thickness of the first alloy member side is 2.0 μm.
First metallization layer 103 made of Au, and the third metallization layer 1 made of Au having a thickness of 0.3 μm on the first alloy member side
05, the first metallization layer 107 of Au having a thickness of 2.0 μm on the second alloy member side and the thickness of the second alloy member side of 0.
3 μm Au third metallization layer 109 to Au
Melts into the second metallized layer 108 of molten Sn to form an Au—Sn combined financial liquid 130. Au-S
The melting point of the n-financing liquid 130 once drops with an increase in the Au concentration, but rises again at the Sn concentration of about 87 mass%. When the heating / heating rate is low, the Au—Sn mixed financial liquid 130 may solidify, but in the present embodiment, the heating / heating rate is sufficiently high so that it does not solidify.

(4) Between states C and D After heating to 593K, the temperature is maintained. A during this time
Dissolution of Au in the u-Sn combined financial liquid 130 proceeds.

(5) State D In this embodiment, the thickness of each metallization layer is adjusted so that the state D is reached when the dissolution of Au in the Au-Sn mixed financial liquid 130 is completed. Therefore, in the state D, the Au-Sn alloy financial liquid, the Ni metallized layer 102 having a thickness of 1 μm on the first alloy member side, and the Ni second alloy member 111 having a thickness of 27 μm.
Makes direct contact with.

(6) Between states D and E Au-Sn mixed financial liquid and N having a thickness of 1 μm on the first alloy member side.
By direct contact between the i metallized layer 102 and the Ni second alloy member 111 having a thickness of 27 μm, the Ni—Sn intermetallic compound 106 is rapidly formed at their interface. The compound 106 also contains a small amount of Au, but most of them are Ni and Sn. Due to the formation of the compound 106, the Sn concentration in the Au—Sn financial liquid 130 decreases, and the melting point of the financial liquid 130 also decreases. This improves the fluidity of the Au-Sn synthetic financial liquid and improves the adhesion of the joint.

(7) State E When the state D is heated for about 10 s, the Ni—Sn intermetallic compound 106 grows, so that the Sn concentration in the Au—Sn alloy financial solution decreases, and the eutectic composition of the Au—Sn alloy is changed. Au-20m
It becomes ass% Sn.

(8) State F If the joint portion is cooled from the state E, it is possible to obtain the joint portion which is joined by the Au—Sn eutectic alloy having excellent strength reliability and corrosion resistance.

(9) State E'When the dissolution of Au in the Au-Sn combined financial liquid 130 is completed, the state is not changed to D, and when undissolved Au remains, Au is left.
The melting point of the -Sn combined financial liquid 130 exceeds 593 K within a few seconds, the state E'becomes established, and solid crystallization begins, and the fluidity of the Au-Sn combined financial liquid 130 is extremely lowered. Since the solidification of the Au—Sn mixed financial liquid 130 starts before the joint is completely adhered, the strength reliability of the joint decreases.

The transition from the state D to the state E occurs in a shorter time than the transition to the state E'due to the growth of the diffusion-controlled Ni-Sn compound in which the transition from the state D to the state E is diffusion-controlled. On the other hand, the transition from the state D to the state E ′ is due to the dissolution of Au in the Au—Sn alloy 130.

In the state E ', the strength reliability of the joint is lowered, but generally, the higher the Au concentration is, the higher the corrosion resistance of the Au-Sn alloy is. Therefore, the joint is required to have the corrosion resistance first. In some cases,

In this embodiment, the growth of the Ni—Sn compound is treated as starting from the state D, but in reality, the growth of the Ni—Sn compound occurs slightly before the state C. In this case, Sn diffuses inside the first metallization layer 103 on the first alloy member side and the first metallization layer 107 on the second alloy member side made of Au and reaches Ni.
-Sn compound is formed. Since this process is diffusion-controlled, the supply amount of Sn per unit time is extremely smaller than between states D and E, and therefore the compound growth rate is also extremely small. As in the present example, when the heating temperature rising rate is 20 K / s or more, Au—Sn accompanying the compound formation before the state D is generated.
The composition change of the synergistic liquid is negligible.

Next, the joining process will be described.

Reference numeral 211 denotes the first metallization layer 103 made of Au and the second metallization layer 104 made of Sn shown in FIG.
And a third metallization layer 105 made of Au, a bonding layer made of three metallization layers, and 221 are first metallization layers 107, 107 made of Au, a second metallization layer 108 made of Sn and a second metallization layer made of Au shown in FIG. A bonding layer composed of three metallized layers of the three metallized layers 109, 212
Reference numerals 222 and 222 denote a pollutant layer composed of an oxide film, water, and an organic substance, 2
30 is a fused and integrated joining layer, 300 is an Ar atom beam, 301 is a resistance welding machine, 302 is a resistance welding tip, 303 is a ground terminal, 304 is a conductive base, 30
Reference numerals 5 and 308 are heating and pressing jigs having a built-in heater, and 306.
Is an aluminum nitride alloy member holding jig having a thickness of 0.5 mm, 307 is a coil spring, 309 is a cooling gas nozzle,
Reference numeral 310 is a gas introduction feedthrough, 311 is an atom source, and 400 is a vacuum chamber.

(1) Setting The first alloy member 101 and the second alloy member 111 are loaded in the vacuum chamber 400, and the chamber is evacuated.

The first alloy member 101 has a Ni metallization layer 102 and a first metallization layer 1 made of Au shown in FIG.
03, a second metallization layer 104 made of Sn and a third metallization layer 105 made of Au. The second alloy member 111 has a first metallization layer 107 made of Au, a second metallization layer 108 made of Sn and Au shown in FIG.
The bonding layer 221 formed of three metallized layers of the third metallized layer 109 is formed. In the state of being evacuated, the contaminant layers 212 and 2 composed of an oxide layer and an adsorbed layer of water, an organic substance or the like are formed on the bonding layers 211 and 221.
22 is formed.

(2) Ar gas generated by introducing Ar gas into the activation atom source 311
The contaminant layers 212 and 222 are removed by utilizing the sputtering phenomenon by the atom beam 300. By this treatment, the surfaces of the bonding layers 211 and 221 are cleaned, and the surfaces are rich in bondability and wettability.

(3) Positioning and Fixing in the Atmosphere The first alloy member 101 and the second alloy member 111 are taken out into the atmosphere and placed on the conductive base 304 grounded by the ground terminal 303, and the bonding layers 211 and 221 are attached. The first alloy member 101 and the second alloy member 111 are opposed to each other, the relative positions of the first alloy member 101 and the second alloy member 111 are adjusted and brought into close contact with each other, and resistance welding is performed using the resistance welding machine 301 and the resistance welding tip 302. The relative position of the member 111 is fixed. By this processing, the subsequent processing can be continued without causing a shift in the relative positions of the first alloy member 101 and the second alloy member 111 without using a positioning jig or the like.

(4) Jig preheating The alloy member holding jig 3 in the vacuum chamber 400 for holding the first alloy member 101 and the second alloy member 111, which are positioned and fixed, in the vacuum chamber 400.
After being evacuated once, an inert gas such as nitrogen or Ar is introduced. At the same time, preheat the heating / pressurizing jigs 305 and 308 with built-in heaters, and 573-593K
Keep on. In this state, the alloy member holding jig 306 is floated from the heating / pressurizing jig 308 by the coil spring 307, and the heating / pressurizing jig 305 is pulled up to a position where it does not contact the second alloy member 111. Therefore, the first alloy member 101
And the second alloy member 111 is heated and pressed by the jigs 305 and 30.
8, the temperature of the first alloy member 101 and the second alloy member 111 rises only up to about 420K even if the heating / pressurizing jigs 305 and 308 are preheated to 593K. 211 and 221 do not melt. As a result, there is almost no mutual diffusion between the Ni metallized layer 102 and the bonding layer 211.

(5) Pressing and heating The heating and pressing jig 305 is pressed down using a pressing device (not shown), and the first alloy member 101 and the second alloy member 111 are pressed and brought into close contact with each other. At this time, the coil spring 307 contracts and the alloy member holding jig 306 comes into contact with the heating / pressurizing jig 308, so that heat is rapidly transferred through the alloy member holding jig 306.
It is transmitted to the alloy member 101 and the second alloy member 111 and rapidly heated. At the same time, since the heating / pressurizing jig 305 is also in contact with the second alloy member 111, heat is transferred to the first alloy member 101 and the second alloy member 111 and rapidly heated. As a result of the heating and pressurization, first, Sn in the bonding layers 211 and 221 is melted, and adjacent Au is melted to form an Au-Sn combined financial liquid. Until Au is completely dissolved in the Au-Sn synthetic financial liquid, Au functions as a barrier layer against the diffusion of Sn into the Ni metallized layer 102 and the second alloy member 111. Since the melting point of the Au—Sn synthetic financial liquid rises as the concentration of Au in Sn increases, the melt once solidifies when the heating temperature raising rate is lower than the melting point raising rate. However, during this time, the mutual diffusion of Sn and Au progresses, and Au-
The melting point of the Sn alloy changes continuously. Heating temperature is 553
When it exceeds K, a eutectic reaction of Au and Sn produces a melt to promote adhesion of the joint. The heating rate is Au-S
If the melting point increase rate of the n-alloy is higher than that of Au-S
The n-alloy layer does not solidify and remains molten.

When the bonding layer 411 is completely melted, adhesion of the bonding portion is promoted and S in the Au-Sn mixed financial liquid is promoted.
The n is directly contacted with the Ni metallized layer 102 and the second alloy member 111 to promote the formation of the Ni—Sn compound, and the Sn concentration in the bonding layer is rapidly reduced.

In the case of this embodiment, the heating temperature rising rate is 20.
If K / sec or more, the Sn concentration in the bonding layer is Au-S.
The joining can be completed before the n-eutectic composition becomes lower than 20 mass% to obtain a strong and airtight joint. Further, the heating temperature may be set to 573 to 593K, which is slightly higher than the eutectic point of Au-Sn alloy, which is 553K, and suppresses thermal damage to the first alloy member 101 and the second alloy member 111 to be small. You can The optimum value of the heating / pressurizing time is obtained in advance by experiments.

(6) Cooling After heating and pressing for a predetermined time, the heating and pressing jig 305 is pulled up and separated from the second alloy member 111. At this time, coil spring 3
07 expands and lifts the alloy member holding jig 306, so that the heating and pressing jigs 305 and 308 cause the first alloy member 1 to move.
01 and the heat inflow to the second alloy member 111 are reduced.
Next, an inert gas such as Ar or N ₂ is sprayed onto the bonding layer 230 integrated with the first alloy member 101 and the second alloy member 111 through the gas introduction feedthrough 310 and the cooling gas nozzle 309 to rapidly cool the bonding portion. To be done. By this rapid cooling, the growth of the Ni—Sn compound layer formed at the interface between the bonding layer 230, the Ni metallized layer 102, and the second alloy member 111 can be suppressed, and a strong and airtight bonded portion can be obtained. be able to.

(7) Taking out The first alloy member 101 and the second alloy member 111 are taken out from the vacuum chamber 400, and the joining is completed. The joining layer 2 in which the first alloy member 101 and the second alloy member 111 are integrated
It is firmly joined by 30.

In the case of this embodiment, the heating rate is 20 K /
When it is smaller than sec, the Sn concentration in the bonding layer becomes lower than 20 mass% which is the Au—Sn eutectic composition before the bonding layer melts and becomes completely integrated. as a result,
Since the melting point of the bonding layer rises rapidly and the bonding layer solidifies with the bonding layer being incompletely integrated, a strong and airtight bonded portion cannot be obtained. However, when the composition of the bonding layer is different from that of the present embodiment, the heating temperature rising rate does not necessarily need to be 20 K / sec or more.

In this embodiment, the Sn concentration of the bonding layer is set to 23 ma.
Although the ss% is set, the Sn concentration exceeds 20 mass% and is 40
If it is less than mass%, good joining is possible. In this range, as described above, when the Sn concentration in the bonding layer decreases due to the formation of the Ni-Sn compound, the composition of the bonding layer approaches the eutectic composition, and the melting point of the bonding layer decreases. As a result, there is sufficient time for the bonding layer to melt and integrate during heating and pressing, and a strong and airtight bonded portion can be obtained.
On the other hand, the bonding layer composition is 20 mass% or less and 40 mass% or less.
When the Sn concentration is s% or more, the melting point of the bonding layer rises rapidly when the Sn concentration decreases, and there is no time margin for the bonding layer to melt and integrate. As a result, a bonding defect such as a void or an unbonded portion is generated in the bonded portion, which lowers the bonding strength and airtightness.

In the present embodiment, the joining layer is made of Au--Sn alloy, but if the melting point of the joining layer changes due to the change of the joining layer composition during joining, the melting point is lowered during joining. By setting the composition, a good bonded portion can be obtained as in the present embodiment.

In this embodiment, two alloy members, the first alloy member and the second alloy member, are used, but any number of laminated members can be joined by repeating the joining process according to the present invention. It is also possible to position-fix and fix three or more alloy members by repeating the positioning process and the fixing process by resistance welding, and heat-bonding them all at once.

Next, another embodiment of the joining method of the present invention will be described with reference to FIGS.

First, a method for forming a metallized layer on an alloy member will be described.

101 is a 50 μm thick SUS304 first alloy member, 102 is a 1 μm thick Ni metallized layer,
Reference numeral 501 denotes a first metallization layer made of Au having a thickness of 1.15 μm, 502 denotes a second metallization layer made of Sn having a thickness of 1.8 μm, 503 denotes a third metallization layer made of Au having a thickness of 1.15 μm, and 111 denotes It is a Ni second alloy member having a thickness of 27 μm.

The first alloy member 101 made of SUS304 is electrolessly plated with Ni—P to a thickness of 1 μm by wet plating. The thickness does not necessarily have to be 1 μm, but it is necessary that the Ni is not completely consumed as a compound with Sn after bonding. Ni-Sn compound is SUS3
If the bonding property with 04 is poor and all of Ni is consumed as a compound with Sn after bonding, the bonding strength will be extremely lowered. Next, as the first metallized layer 501, the thickness 1.1
Au of 5 μm is formed by wet plating. Next, as the second metallized layer 502, Sn having a thickness of 1.8 μm is formed by wet plating. Further, Au having a thickness of 1.15 μm is formed by wet plating as the third metallized layer 503. The Ni second alloy member 111 is manufactured by electroforming. Since electroformed Ni has good bondability with the Au-Sn alloy, it is not necessary to apply Ni metallization to the bonded surface.

In the present invention, all the metallized layers are formed by wet plating, but the same effect can be obtained by forming all or part of the metallized layers by other film forming means such as vacuum deposition or sputtering. Is obtained.

Next, the joining process will be described.

Reference numerals 212 and 222 denote a contaminant layer made of an oxide film, water, or an organic material, 430 a fused and integrated joining layer, 300 an Ar atom beam, 301 a resistance welding machine,
302 is a resistance welding tip, 303 is a ground terminal, 304
Is a conductive base, 305 and 308 are heating and pressing jigs with built-in heaters, 306 is an aluminum nitride alloy member holding jig having a thickness of 0.5 mm, 307 is a coil spring, 30
Reference numeral 9 is a cooling gas nozzle, 310 is a gas introduction feedthrough, 311 is an atom source, and 400 is a vacuum chamber.

(1) Setting The first alloy member 101 and the second alloy member 111 are loaded into the vacuum chamber 400, and the chamber is evacuated.

The first alloy member 101 has a Ni metallization layer 102 and a first metallization layer 5 made of Au shown in FIG.
A bonding layer 411 made up of three metallized layers, that is, a second metallized layer 502 made of 01 and Sn and a third metallized layer 503 made of Au is formed. When evacuated, the bonding layer 411 and the second alloy member 111 have
Contaminant layer 2 consisting of oxide layer and adsorbed layer of water, organic matter, etc.
12 and 222 are formed.

(2) Ar gas generated by introducing Ar gas into the activation atom source 311
The contaminant layers 212 and 222 are removed by utilizing the sputtering phenomenon by the atom beam 300. By this treatment, the surfaces of the bonding layer 411 and the second alloy member 111 are cleaned, and the surfaces are rich in bondability and wettability.

(3) Positioning and Fixing in the Atmosphere The first alloy member 101 and the second alloy member 111 are taken out into the atmosphere and placed on the conductive base 304 grounded by the ground terminal 303, and the bonding layer 411 and the second layer The alloy members 111 are made to face each other, the relative positions of the first alloy member 101 and the second alloy member 111 are adjusted and then closely contacted, and resistance welding is performed using the resistance welding machine 301 and the resistance welding tip 302. And the relative position of the second alloy member 111 is fixed. By this process, the first alloy member 101 and the second alloy member 1 can be used without using a positioning jig or the like.
Subsequent processing can be continued without causing a shift in the relative position of 11.

(4) Jig preheating The alloy member holding jig 3 in the vacuum chamber 400 is provided with the first alloy member 101 and the second alloy member 111 which are positioned and fixed.
After being evacuated once, an inert gas such as nitrogen or Ar is introduced. At the same time, preheat the heating / pressurizing jigs 305 and 308 with built-in heaters, and 573-593K
Keep on. In this state, the alloy member holding jig 306 is floated from the heating / pressurizing jig 308 by the coil spring 307, and the heating / pressurizing jig 305 is pulled up to a position where it does not contact the second alloy member 111. Therefore, the first alloy member 101
And the second alloy member 111 is heated and pressed by the jigs 305 and 30.
8, the temperature of the first alloy member 101 and the second alloy member 111 rises only up to about 420K even if the heating / pressurizing jigs 305 and 308 are preheated to 593K. 411 does not melt. As a result, there is almost no mutual diffusion between the Ni metallized layer 102 and the bonding layer 411.

(5) Pressurization and heating The heating and pressurizing jig 305 is pressed down using a pressurizing device (not shown), and the first alloy member 101 and the second alloy member 111 are pressed and brought into close contact with each other. At this time, the coil spring 307 contracts and the alloy member holding jig 306 comes into contact with the heating / pressurizing jig 308, so that heat is rapidly transferred through the alloy member holding jig 306.
It is transmitted to the alloy member 101 and the second alloy member 111 and rapidly heated. At the same time, the heating / pressurizing jig 305 is also attached to the second alloy member 1.
Since it is in contact with 11, the heat is transferred to the first alloy member 101 and the second alloy member 111 to be rapidly heated. As a result of the heating and pressurization, first, Sn in the bonding layer 411 is melted, and adjacent Au is melted to form an Au-Sn synthetic financial liquid. In the present embodiment, Au as the first and second metallized layers adjacent to Sn have the same thickness, and until the Au is completely dissolved in the Au-Sn mixed financial liquid, the Ni metallized layer 1 of Sn is formed.
02 and the second alloy member 111 function as a barrier layer against diffusion. As the concentration of Au in Sn increases, the melting point of the Au-Sn combined financial liquid rises. Therefore, when the heating temperature rising rate is lower than the melting point rising rate, the melt temporarily solidifies. However, during this time, the mutual diffusion of Sn and Au proceeds, and the melting point of the Au—Sn alloy continuously changes. When the heating temperature exceeds 553 K, a eutectic reaction of Au and Sn produces a melt, which promotes adhesion of the joint. When the heating temperature rising rate is higher than the melting point rising rate of the Au-Sn alloy, the Au-Sn alloy layer does not solidify and maintains the molten state.

When the bonding layer 411 is completely melted, adhesion of the bonding portion is promoted and S in the Au-Sn mixed financial liquid is promoted.
The n is directly contacted with the Ni metallized layer 102 and the second alloy member 111 to promote the formation of the Ni—Sn compound, and the Sn concentration in the bonding layer is rapidly reduced. In the case of the present embodiment, if the heating rate is 20 K / sec or more, the Sn concentration in the bonding layer is 20 mass, which is the Au—Sn eutectic composition.
It is possible to complete the joining before it becomes lower than 10% and obtain a strong and airtight joined portion. The heating temperature is Au-S.
Slightly higher than 553K, which is the eutectic point for n-based alloys
It should be 73 to 593K, and thermal damage to the first alloy member 101 and the second alloy member 111 can be suppressed to be small. The optimum value of the heating / pressurizing time is obtained in advance by experiments.

(6) Cooling After heating and pressing for a predetermined time, the heating and pressing jig 305 is pulled up and separated from the second alloy member 111. At this time, coil spring 3
07 expands and lifts the alloy member holding jig 306, so that the heating and pressing jigs 305 and 308 cause the first alloy member 1 to move.
01 and the heat inflow to the second alloy member 111 are reduced.
Next, an inert gas such as Ar or N ₂ is sprayed onto the bonding layer 430 integrated with the first alloy member 101 and the second alloy member 111 through the gas introduction feedthrough 310 and the cooling gas nozzle 309 to rapidly cool the bonding portion. To be done. By this rapid cooling, the growth of the Ni—Sn compound layer formed at the interface between the bonding layer 430 and the Ni metallized layer and the second alloy member 111 can be suppressed, and a strong and airtight bonded portion can be obtained. You can

(7) Taking out The first alloy member 101 and the second alloy member 111 are taken out from the vacuum chamber 400, and the joining is completed. The joining layer 4 in which the first alloy member 101 and the second alloy member 111 are integrated
It is firmly joined by 30.

In the case of this embodiment, the heating rate is 20 K /
When it is smaller than sec, the bonding layer is melted and then completely integrated, and at the same time, the Sn concentration in the bonding layer is Au—Sn.
It becomes lower than 20 mass% which is a eutectic composition. As a result, the melting point of the bonding layer rapidly rises and the bonding layer solidifies while the adhesion of the bonding layer is incomplete, so that a strong and airtight bonded portion cannot be obtained. However, if the composition of the bonding layer is different from that of this embodiment, the heating rate is not necessarily 20 K / sec.
There is no need to go above.

In this embodiment, the Sn concentration of the bonding layer is 23 ma.
Although the ss% is set, the Sn concentration exceeds 20 mass% and is 40
If it is less than mass%, good joining is possible. In this range, as described above, when the Sn concentration in the bonding layer decreases due to the formation of the Ni-Sn compound, the composition of the bonding layer approaches the eutectic composition, and the melting point of the bonding layer decreases. As a result, there is enough time for the bonding portion to completely adhere after the bonding layer melts during heating and pressing, and a strong and airtight bonding portion can be obtained. On the other hand, when the composition of the bonding layer is 20 mass% or less and 40 mass% or more, when the Sn concentration decreases, the melting point of the bonding layer rapidly rises, and there is no time to fully bond the bonding portion. As a result, a bonding defect such as a void or an unbonded portion is generated in the bonded portion, which lowers the bonding strength and airtightness.

In the present embodiment, the bonding layer is made of Au--Sn alloy, but if the melting point of the bonding layer changes due to the change of the bonding layer composition during bonding, the melting point of the alloy composition decreases during bonding. By setting the composition, a good bonded portion can be obtained as in the present embodiment.

In this embodiment, two alloy members, the first alloy member and the second alloy member, are used. However, it is possible to carry out laminated bonding by repeating the bonding process according to the present invention. It is also possible to position-fix and fix three or more alloy members by repeating the positioning process and the fixing process by resistance welding, and heat-bonding them all at once.

[0068]

According to the present invention, the thickness is 10 μm to 5 μm.
An object to be bonded, which is composed of a combination of a 0-micron SUS304 plate and a thin plate made of Ni, is cleaned with an argon atom beam in a vacuum by using a bonding layer composed of three metallized layers of Au, Sn, and Au, and then air. Positioning and fixing are performed inside, and then pressure heating bonding is performed in vacuum or in an inert gas. Bonding with excellent corrosion resistance without thermal damage to SUS304 plate and electroformed Ni plate. It can be performed.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an example according to a metallized layer forming method of a joining method of the present invention.

FIG. 2 is a diagram illustrating a joint structure in each joining process of the embodiment according to the joining method of the present invention.

FIG. 3 is a view for explaining the structure and melting point of the Au—Sn synthetic financial liquid layer in each joining process of the example according to the joining method of the present invention.

FIG. 4 is a diagram illustrating an example according to the joining method of the present invention.

FIG. 5 is a diagram illustrating an example of a metallized layer forming method of the joining method of the present invention.

FIG. 6 is a diagram illustrating an example according to the joining method of the present invention.

[Explanation of symbols]

101 is a 50 μm thick SUS304 first alloy member,
102 is a Ni metallization layer having a thickness of 1 μm, 103 is a first metallization layer made of Au having a thickness of 2.0 μm, 104 is a second metallization layer made of Sn having a thickness of 1.8 μm, 10
5 is a third metallization layer made of Au having a thickness of 0.3 μm,
106 is a Ni-Sn intermetallic compound on the first alloy member side, 1
07 is a first metallization layer made of Au having a thickness of 2.0 μm on the second alloy member side, and 108 is a thickness of 1.
Second metallization layer made of 8 μm Sn, 109 is second
A third metallization layer made of Au having a thickness of 0.3 μm on the alloy member side, 110 is a Ni—Sn intermetallic compound on the second alloy member side, 111 is a Ni alloy member having a thickness of 27 μm, 130
Is Au-Sn combined financial liquid, 300 is Ar atom beam, 3
01 is a resistance welding machine, 302 is a resistance welding tip, 303 is a ground terminal, 304 is a conductive base, 305 and 308 are heating and pressing jigs with a built-in heater, and 306 is a thickness of 0.5 m.
m alloy jig made of aluminum nitride, 307 coil spring, 309 cooling gas nozzle, 310 gas feed feedthrough, 311 atom source, 400 vacuum chamber, 411 bonding layer, 430 melted and integrated The joining layer 501 is a first metallization layer 501 made of Au having a thickness of 1.15 μm, and 502 is Sn having a thickness of 1.8 μm.
A second metallized layer 503, which has a thickness of 1.15 μm
Is a third metallization layer made of Au.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunihiro Tamahashi 1060 Takeda, Katsuta-shi, Ibaraki Hitachi Koki Co., Ltd. (72) Inventor Yuji Furuya 1060 Takeda, Katsuta-shi, Ibaraki Hitachi Koki Co., Ltd. (72) ) Inventor Kenichi Hisagai 1060 Takeda, Katsuta City, Ibaraki Hitachi Koki Co., Ltd.

Claims (6)

[Claims] 1. A member for joining a first surface of a first alloy member to a second surface of a second alloy member of a plurality of alloy members constituting an ink jet print head, the first surface and the second surface of the alloy member. Of the first metallization layer, Au as the second metallization layer, and A as the third metallization layer on at least one surface from the base material side.
A three-layer metallized layer is formed in the order of u, and the first surface and the second surface are arranged face to face, the relative positions of the first surface and the second surface are adjusted, and then the layers are brought into close contact with each other. A method for joining an inkjet print head, comprising heating the alloy member to a temperature of 553 K or higher to melt the three-layer metallized layer and joining the first and second alloy members without melting the alloy member. 2. The thickness of each of the first, second and third metallized layers is such that the Sn content in the entire three metallized layers is 20 m.
a three-layer metallized layer with a thickness of the first metallized layer of 1 μm or more and a total thickness of the three-layered metallized layer of 3 μm or more on the first and second surfaces of the alloy member. The method for joining an inkjet print head according to claim 1, wherein the method is formed and used for joining. 3. The thickness of each of the first, second and third metallized layers is such that the Sn content in the entire three metallized layers is 20 m.
more than ass% and less than 40 mass%, the first metallization layer and the third metallization layer have the same thickness, and the total thickness of the three-layer metallization layer is 3 μm or more. A method for joining an ink jet print head, comprising forming on any one of the second surfaces and using it for joining. 4. After activating the first surface of the first alloy member and the second surface of the second alloy member with an Ar beam, the relative positions of the first surface and the second surface are adjusted in the atmosphere. Make it close,
After that, the first and second alloy members are heated in a vacuum or in an inert gas to a temperature of 553 K or higher without melting the first and second alloy members to melt the three-layer metallized layer. It joins, The claim 1 characterized by the above-mentioned.
The method for joining inkjet print heads according to 2 and 3. 5. A jig preheated and maintained at a predetermined temperature,
The first and second parts are brought into close contact with each other after adjusting the relative position.
Press on the alloy member and heat it to a temperature of 553K or higher, and
After the layer metallized layer is melted and the first and second alloy members reach a predetermined temperature, an inert gas is added to the first and second alloy members.
The method for joining inkjet print heads according to claim 4, wherein the alloy member is sprayed and cooled. 6. After adjusting the relative position of the first surface of the first alloy member and the second surface of the second alloy member, and before heating, resistance welding or mechanical fastening is used to make the first alloy member and The method for joining inkjet print heads according to claim 4, wherein the two alloy members are fixed.