JP2003026481A - Ceramic joined material and parts used with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceramic joined material formed by laminating and joining a ceramic base material and a conductive plate without using a high-temperature process and parts used with the same. SOLUTION: The ceramic joined material 20 is obtained by subjecting the surfaces facing each other of a conductive plate 26 and a ceramic base material 28 housed in a recessed part 34a of a cylindrical body section of a vessel to activation treatment under an extremely low pressure, touching, superposing and laminating the flanged section 34b and the conductive plate 36 of the cylindrical body section of the vessel in the state of housing the ceramic base material 28, hermetically press welding the flanged section in a vacuum or reduced pressure state to form the hermetic vessel 30 and subjecting this hermetic vessel to isostatic pressurizing thereby laminating and joining the conductive plate 26 and the ceramic base material 28. Parts, such as printed circuit boards, are produced by using such ceramic joined material 20.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a ceramic bonding material in which a ceramic base material and a conductive plate are laminated and bonded, and a component using the same.

[0002]

2. Description of the Related Art Conventionally, ceramic members have excellent properties such as heat resistance, wear resistance, and electrical insulation, but
Since it is generally considered to have poor toughness, many composite materials in which a metal material and a ceramic member are joined have been proposed and have been applied in a wide range of fields such as electronics, automobiles, and industrial parts.

Several methods such as a high melting point metal method, an active metal method, and a vapor deposition method have been proposed as a method for joining a ceramic member and a metal material. In addition to this, for example, Japanese Patent Laid-Open No. Hei 4
JP-A-46070 proposes a method in which a joint surface between a ceramic member and a metal material is activated under an extremely low pressure and cold-welded in a vacuum chamber.

[0004]

However, the conventional joining method as described above has the following problems.
That is, when a high temperature process is used, there are adverse effects such as residual stress due to a difference in thermal expansion and formation of a fragile compound layer at the bonding interface, and when a relatively thick conductor such as metal is required, a plurality of However, there are complications such as having to use different manufacturing processes together. Further, when cold pressure welding is performed in a vacuum chamber, there is a problem that the ceramic material may be damaged due to brittleness or the like.

In view of the above technical background, the present invention has a ceramic bonding material in which a conductive material having a required thickness is laminated and bonded to a ceramic substrate by hydrostatic pressing, and a printed wiring using the ceramic bonding material. It is an object to provide components such as boards and IC packages.

[0006]

As a first solution to the above-mentioned problems, a ceramic bonding material of the present invention is a ceramic bonding material obtained by laminating and bonding a ceramic base material and a conductive plate. Activated the flange of the container body containing the material and the ceramic base,
An airtight container is formed by press-contacting the conductive plate and the flange portion of the container body, and the conductive plate and the ceramic substrate are laminated and bonded by performing hydrostatic pressure on the airtight container. did.

As a second means for solving the above problems, in the ceramic bonding material of the present invention, the activation treatment in the first means causes glow discharge in an inert gas atmosphere, and the conductive plate surface and the ceramic are joined. The substrate surface and the flange surface of the container body containing the ceramic substrate are sputter-etched.

As a third means for solving the above problems, in the ceramic bonding material of the present invention, the ceramic base material has a non-planar shape.

As a fourth means for solving the above problems, the component of the present invention has a structure using a ceramic bonding material.
In addition, the parts are configured to be applied to either a printed wiring board or an IC package.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a schematic cross-sectional view showing one embodiment of a ceramic bonding material 20 of the present invention. A ceramic base material 28 in which the entire base material has a substantially flat plate shape, one surface has irregularities, and the other surface is flat. An example is shown in which the conductive plate 26 is laminated and joined to the uneven side surface.

The material of the ceramic base material 28 is not particularly limited as long as it is a material capable of producing a ceramic bonding material, and can be appropriately selected and used according to the application of the ceramic bonding material. For example, alumina, lanthanum chromate, molybdenum silicide, cordierite, sialon, zinc oxide, yttrium oxide, potassium oxide, silicon oxide, tin oxide, titanium oxide, beryllium oxide, boron oxide, magnesium oxide, silica, zirconia, zircon, Zirconate titanate, steatite, spodumene, silicon carbide, titanium carbide, tungsten carbide, boron carbide, strontium titanate, barium titanate, aluminum nitride, silicon nitride, titanium nitride, boron nitride,
Lithium niobate, ferrite, beryllia, forsterite, magnesia, mullite, zirconium boride,
Titanium boride, lanthanum boride, cadmium sulfide,
Molybdenum sulfide, PLZT (Pb, La (Zr, Ti)
O ₃ ), PZT (Pb (Zr, Ti) O ₃ ) and the like,
Crystals, diamonds, DLC (diamond like
Carbon), glass, etc., and those obtained by film-forming them on other base materials (for example, metal materials, alloy materials, glass materials, polymer materials, ceramic materials, etc.), or metal layers or alloy layers using these materials as base materials. A laminated material (evaporated material, plated material, etc.) in which (for example, a material applied to the conductive plate 26) is laminated is applied. Alumina or the like is used when the ceramic bonding material is applied to a printed wiring board or the like.

The sectional shape of the ceramic base material 28 is not particularly limited as long as a ceramic bonding material can be manufactured, and is appropriately selected depending on the application of the ceramic bonding material. For example, it may have a flat plate shape, a substantially arc shape, a substantially spherical shape, or a non-planar shape having irregularities on the surface. If the application of the ceramic bonding material is a printed wiring board or the like, the ceramic base material preferably has a substantially flat cross section, but the ceramic base material may have irregularities on one side or both sides. The thickness of the ceramic base material and the height difference of the unevenness are not particularly limited as long as the ceramic bonding material can be manufactured, and are appropriately selected depending on the application of the ceramic bonding material.

The material of the conductive plate 26 is not particularly limited as long as it is a material capable of producing a ceramic bonding material, and can be appropriately selected and used according to the application of the ceramic bonding material. For example, a metal that is solid at room temperature (eg, Al, Ni, Cu, Ag, Pt, Au, etc.) or an alloy containing at least one of these metals (eg,
JIS specified alloys) or a laminate having at least one layer of these metals or alloys (eg, clad material,
Plating materials, vapor deposition film materials, etc.) are applied. If the application of the ceramic bonding material is a printed wiring board, it has Cu, Al, etc., which are metals having excellent conductivity as electrodes, an alloy containing at least one of these metals, or at least one layer of these metals or alloys. A laminated body or the like is applied.

In addition to alloy steel and stainless steel as the alloy specified in JIS, for example, Cu-based alloys include oxygen-free copper,
With Al-based alloys such as tough pitch copper, phosphorous deoxidized copper, red copper, brass, free-cutting brass, tin-containing brass, Admiralty brass, naval brass, aluminum bronze, and white copper, 2000
System, 3000 series, 5000 series, 6000 series, 7000 series, etc., Ni-based alloys include normal carbon nickel, low carbon nickel, nickel-copper alloy, nickel-copper-aluminum-
A titanium alloy, a nickel-molybdenum alloy, a nickel-molybdenum-chromium alloy, a nickel-chromium-iron-molybdenum-copper alloy, a nickel-chromium-molybdenum-iron alloy, etc. can be applied.

The thickness of the conductive plate 26 is not particularly limited as long as the ceramic bonding material can be manufactured, and is appropriately selected depending on the application of the ceramic bonding material. For example, 1-100
It is preferably 0 μm. If it is less than 1 μm, it becomes difficult to manufacture it as a conductive plate, and if it exceeds 1000 μm, it becomes difficult to manufacture it as a ceramic bonding material. More preferably, it is 10 to 500 μm.

A method of manufacturing the ceramic bonding material 20 shown in FIG. 1 will be described. First, the ceramic base material 28 is placed in the concave portion 34a of the container body portion, and the ceramic base material 28 and the conductive plate 26 placed in the container body portion 34 are loaded into the vacuum chamber.
The surfaces to be joined of the conductive plate 26 and the ceramic base material 28 are each subjected to activation treatment by an activation treatment device. At this time, the side surface of the flange portion 34b of the container body portion to be joined with the conductive plate 26 of the container body portion 34 is also activated.

The activation treatment of the ceramic base material 28 and the conductive plate 26 used for the ceramic bonding material 20 is carried out as follows. That is, the container body 34 accommodating the ceramic base material 28 loaded in the vacuum chamber and the conductive plate 26 are brought into contact with one electrode A which is insulated and supported, and between the other electrode B which is grounded. 10 ~ 1 x 10 ^-3 P
A ceramic substrate 28 in contact with the electrode A exposed in plasma generated by glow discharge by applying an alternating current of 1 to 50 MHz in an extremely low pressure inert gas atmosphere of a, preferably argon gas The sputter etching process is performed so that the area of each of the container body 34 and the conductive plate 26 in which is stored becomes 1/3 or less of the area of the electrode B. Note that when the inert gas pressure is less than 1 × 10 ⁻³ Pa, stable glow discharge is difficult to perform and high-speed etching is difficult, and when it exceeds 10 Pa, the activation treatment efficiency decreases.
If the applied alternating current is less than 1 MHz, it is difficult to maintain a stable glow discharge, and continuous etching is difficult.
If it exceeds 0 MHz, oscillation is likely to occur and the power supply system becomes complicated, which is not preferable. Further, in order to perform etching efficiently, it is necessary to make the area of each of the container body 34 accommodating the ceramic base material 28 in contact with the electrode A and the conductive plate 26 smaller than the area of the electrode B, which is 1/3 or less. By doing so, etching can be performed with sufficient efficiency.

Then, the flange portion 34b of the container body containing the activated ceramic base material 28 and the conductive plate 26 are activated as shown in FIG. 2 so that they can be pressure-treated by the hydrostatic pressure device. The surfaces that have been subjected to the chemical treatment face each other so that they are in contact with each other and are laminated on top of each other, and the flange portion 34b of the container body is cooled with a pressing device having a pressing surface corresponding to the shape of the airtight container under vacuum or reduced pressure. The airtight container 30 is manufactured by forming the joint portion 36 by performing pressure contact. As the pressurizing condition for this pressure contact, it is sufficient that the material to be joined is a low-strength material and the pressure is equal to or higher than the yield strength. More preferably, among the materials to be joined, the pressing is performed at a pressure of 2 to 3 times the yield strength of the low-strength material. The upper limit of the pressing force may be within a range that does not cause breakage during joining.
At this time, the activated surfaces of the ceramic base material 28 and the conductive plate 26 are kept active in the airtight container 30.

The material of the container body 34 forming the airtight container 30 can be appropriately selected depending on the hydrostatic processing conditions and the like and is not particularly limited as long as it is a material applicable to the conductive plate 26, and the same material as the conductive plate 26 or a different material. But it's okay. The thickness of the container body 34 may be the same as or different from that of the conductive plate 26.

Thereafter, the sealed airtight container 30 is hydrostatically pressurized by a hydrostatic pressure device to laminate and join the ceramic base material 28 and the conductive plate 26. At this time, the conductive plate 26 is molded by using the ceramic base material 28 as a molding die like bulging.
Since isostatic pressure is applied by hydrostatic pressure, the brittleness of the ceramic base material 28 can be overcome and pressure welding can be performed. As the pressurizing medium for hydrostatic pressurization, a known one such as water, liquid such as oil, or gas can be used. The conductive plate 26
When the brittleness of the ceramic base material 28 becomes a problem due to the force required for the plastic deformation, the conductive plate 26 may be preliminarily formed into a shape corresponding to the uneven shape of the ceramic base material 28. The hydrostatic pressure at this time is 1 × 10 ⁸ to, for example, when copper or aluminum is used for the conductive plate 26.
1.5 × 10 ⁹ Pa is preferable. If it is less than 1 × 10 ⁸ Pa, a sufficient bonding force cannot be obtained, and if it exceeds 1.5 × 10 ⁹ Pa, the pressure device becomes large, which is not preferable. More preferably, it is 3 × 10 ⁸ to 1 × 10 ⁹ Pa. The lamination joining at this time can be performed at a low temperature, and it is possible to reduce or eliminate adverse effects such as a structural change in the ceramic base material 28, the conductive plate 26, and the lamination joining. T
Is the temperature (° C) of the ceramic substrate and conductive plate, 0
A good pressure contact state can be obtained at a temperature of <T ≦ 300 ° C. If the temperature is 0 ° C. or lower, a special cooling device is required, and if it exceeds 300 ° C., adverse effects such as microstructural change occur, which is not preferable.

As described above, the ceramic joining material 20 as shown in FIG. 1 is obtained by laminating and joining by hydrostatic pressure.
Then, the airtight container 30 is taken out from the hydrostatic pressure application device and left open or cut into an appropriate size if necessary to manufacture the ceramic bonding material 20.

In the airtight container 30 shown in FIG. 2, the portion of the concave portion 34a of the container body on which the ceramic base material 28 is placed is not subjected to activation treatment, so that compared with the bonding surface between the upper surface of the ceramic base material 28 and the conductive plate 26. Thus, the adhesive force between the bottom surface of the ceramic substrate 28 and the recess 34a of the container body portion due to the pressure is very weak and does not pose a problem during opening. However, it may be activated depending on the shape such as the side surface of the ceramic base material 28, the side surface of the body of the container, or a part of the concave portion, and if a problem occurs during opening, insert a cushioning material having an inactive surface if necessary. May be. The material and thickness of the cushioning material are not particularly limited as long as they can be applied to the conductive plate 26, and may be the same as or different from those of the conductive plate 26 and the container body 34.
Further, as shown in FIG. 3, instead of the conductive plate 26, a ceramic bonding material can be manufactured by using the conductive plate 26 holding the conductive plate 22 by using an appropriate means such as an adhesive. In this case, the conductive plate 22 is laminated and joined to the ceramic base material 28. The material and thickness of the conductive plate 22 are not particularly limited as long as they can be applied to the conductive plate 26.
It may be the same as or different from the conductive plate 26.

The ceramic bonding material thus manufactured may be heat-treated to remove or reduce residual stress of the conductive plate, if necessary.

Further, the ceramic bonding material obtained by laminating and bonding conductive plates on both sides is the ceramic base material 2 in the above description.
Ceramic bonding material 2 having a conductive plate on one side instead of 8
It is manufactured in the same manner by using 0.

Alumina is used as the ceramic base material of the ceramic bonding material of the present invention, and copper or the like having excellent conductivity is used for the conductive plate. A circuit board can be obtained by forming a circuit pattern by etching or the like. Therefore, it can be applied to printed wiring boards such as power semiconductors, module boards, and hybrid IC boards.
(Chip size package or chip scale package) and BGA (ball grid array) and other IC packages can also be applied.

[0026]

Embodiments Embodiments will be described below with reference to the drawings.
An alumina substrate having a thickness of 500 μm was used as the ceramic base material 28, a copper foil having a thickness of 35 μm was used as the conductive plate 26, and a 100 μm thick recessed aluminum container was used as the container body 34. The alumina substrate and the copper foil contained in the aluminum container are set in the ceramic bonding material manufacturing apparatus, and the flange portion 34b of the container body is
The alumina substrate and the copper foil were subjected to activation treatment by a sputter etching method in an activation treatment unit in an argon gas atmosphere of 10 ⁻² Pa. Next, the flange portion 34b of the container body containing the activated alumina substrate and the copper foil are brought into contact with each other and laminated, and airtightly pressure-contacted in a depressurized state to form an airtight container 30. After treating with a pressure of about 8 × 10 ⁸ Pa, the airtight container 30 was taken out, opened, and cut into a predetermined size to manufacture the ceramic bonding material 20.

[0027]

As described above, in the ceramic bonding material of the present invention, the conductive plate, the ceramic base material, and the flange portion of the container body containing the ceramic base material are activated and then the ceramic base material is stored. The flange portion of the body of the container and the conductive plate are brought into contact with each other so as to face each other, and the conductive plate and the ceramic substrate are laminated by stacking them by cold pressure to form an airtight container, and applying hydrostatic pressure to the conductive plate and the ceramic base material. It is formed by stacking and joining. Therefore, even if it has a non-planar shape, an isotropic pressure contact force acts on each joint of the ceramic joint material, so that a sufficient joint force can be obtained. Furthermore, without using a high temperature process, it is possible to eliminate or reduce adverse effects such as residual stress due to thermal expansion difference and formation of a fragile compound layer at the bonding interface.
Application to printed wiring boards and the like is also suitable.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a ceramic bonding material of the present invention.

FIG. 2 is a schematic cross-sectional view showing an embodiment of an airtight container used for manufacturing the ceramic bonding material of the present invention.

FIG. 3 is a schematic cross-sectional view showing another embodiment of the airtight container used for manufacturing the ceramic bonding material of the present invention.

[Explanation of symbols]

20 Ceramic bonding material 22 Conductive plate 26 Conductive plate 28 Ceramic substrate 30 airtight container 34 Container body 34a Recess of container body 34b Flange of container body 36 joint

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C23F 4/00 C23F 4/00 A H05K 1/02 H05K 1/02 A 3/00 3/00 R 3 / 38 3/38 D // B23K 101: 40 B23K 101: 40 101: 42 101: 42 (72) Inventor Shinji Osawa 1 No. 1296 Higashitoyoi, Shimomatsu City, Yamaguchi Prefecture Toyo Kohan Co., Ltd. Technical Research Institute F-term (reference) 4E067 AA01 AA18 BA06 DA05 DA13 DA17 DB01 DB03 EA04 EC02 4G026 BA03 BB22 BC01 BC02 BD04 BD08 BF57 BG03 BG14 BG23 BH07 4K057 DA01 DB04 DB20 DD02 DK10 DN10 5E338 ABB01 AA05 AA18 EE60 5E338 ABB01 AA05 AA18 EE60 5E338 AA01 AA05 AA18 EE60 5E338 ABB01

Claims (5)

[Claims] 1. A ceramic bonding material comprising a ceramic base and a conductive plate laminated and bonded together, wherein the conductive plate, the ceramic base and the flange of the container body containing the ceramic base are activated. The conductive plate and the flange portion of the container body are pressure-contacted to each other to form an airtight container, and the conductive plate and the ceramic substrate are laminated and joined by applying hydrostatic pressure to the airtight container. Ceramic bonding material characterized by. 2. The activation treatment is such that glow discharge is performed in an inert gas atmosphere, and the conductive plate surface, the ceramic base material surface, and the container body flange portion surface accommodating the ceramic base material are sputter-etched. The ceramic bonding material according to claim 1, wherein: 3. The ceramic bonding material according to claim 1, wherein the ceramic base material has a non-planar shape. 4. A component using the ceramic bonding material according to claim 1. 5. The component according to claim 4, wherein the component is one of a printed wiring board and an IC package.