CN100471668C - Metal/ceramic bonded products - Google Patents

Abstract

The present invention provides a metal/ceramic bonded article which ensures sufficiently high resistance to sudden changes in temperature, has a small outer dimension of the substrate, and at the same time has high reliability and is compact. The metal/ceramic bonded article comprises: a ceramic substrate and a metal sheet bonded to the ceramic substrate by brazing solder, the length of the brazing solder layer protruding from the bottom surface of the metal sheet is greater than 30 microns, 250 microns or more Short, or the length of the brazing solder layer protruding from the bottom surface of the metal sheet is 25% or more of the thickness of the metal sheet.

Description

Metal/ceramic bonded products

field of invention

The present invention generally relates to a metal/ceramic bonded article having a ceramic substrate and a metal sheet bonded to the ceramic substrate by a brazing solder. More specifically, the present invention relates to a metal/ceramic bonded article on which a semiconductor or the like is mounted, which can be used in a power module or a Peltier element module.

technical background

In a general method of manufacturing ceramic circuit boards for power modules or mounting semiconductors thereon, a metal sheet and a ceramic substrate are first bonded to each other. For example, the direct bonding method adopted in the industry is to place a copper sheet on a ceramic substrate, the copper sheet directly contacts the ceramic substrate, and then heat the copper sheet and the ceramic substrate in an inert gas to bond the two to each other. Brazing and soft soldering methods are also used in the industry. Through the brazing solder containing active metals such as Ti, Zr or Hf, the copper sheet is placed on the ceramic substrate, and then heated in a vacuum to make the ceramic substrate and the ceramic substrate. The copper sheets are bonded to each other. In the brazing process, the active metal acts with a ceramic matrix bonded to the metal sheet. Specifically, the ceramic matrix reacts with the brazing solder to form a reaction product. It is generally believed that the active metal in the brazing solder reacts with the oxide ceramic matrix such as Al ₂ O ₃ to form the oxide of the active metal; it reacts with the non-oxide ceramic matrix such as AlN or Si ₃ N ₄ to form the nitrogen of the active metal Carbides; react with a carbide-based ceramic matrix such as SiC to form carbides of the active metal; these products bond the ceramic matrix to the copper sheet. That is, the bonded brazing solder layer includes a layer mainly containing metal and a layer mainly containing interfacial products between the brazing solder and the ceramic matrix.

For circuits or radiation, as a method of forming a pattern to form a circuit of a predetermined shape after bonding a metal sheet such as a copper sheet, an etching method is also used to form a printed circuit board or the like. The method is widely used because it is easy to obtain fine patterns and can be adapted to changes in circuit design with relative ease. In this method, a mixed solution of, for example, ferric chloride or copper chloride, hydrochloric acid, and hydrogen peroxide is generally used as an etchant for a metal piece such as a copper piece. In the case of the direct bonding method described above, the etchant enables etching to form a pattern without causing a problem because the reaction product can be ignored at this time. However, in the case of brazing and brazing methods, although the etchant can dissolve the metal sheet, it cannot dissolve the brazing solder and the reaction product of the brazing solder and the ceramic matrix (the brazing solder and its reaction products are collectively referred to below as "soldering solder, etc."), with the result that the soldering solder, etc. remains between the circuit board patterns and/or on the edge of the substrate. Since brazing solder and the like are conductors, they cannot satisfy the basic requirements of circuit boards for separating circuit patterns from each other, and/or separating the front and back sides of the board from each other. As a method for removing brazing solder, etc., it is known that hydrofluoric acid or a mixed acid of hydrofluoric acid and at least one inorganic acid selected from nitric acid, sulfuric acid, and hydrochloric acid can be used alone, or an acid containing aqua regia, sodium hydroxide, and / or a solution of potassium hydroxide to process and remove brazing solder, etc. (see Japanese Patent No. 2594475). There is also known a method of removing brazing solder by treating brazing solder etc. with a solution containing hydrogen halide and/or ammonium halide, and then treating with a solution containing mineral acid and hydrogen peroxide (see Japanese Patent No. 7-36467).

On the metal circuit portion of the metal/ceramic bonded matrix article patterned by the above method, nickel plating, nickel alloy plating, gold plating or protective treatment may be applied depending on the application.

In addition, a chip element such as a semiconductor element is mounted thereon by soldering or the like to be used as a power module or a Peltier element module.

In recent years, power modules and Peltier element modules have been used in harsh environments, and the components used in them are required to have high reliability. Especially when it is used as an automobile part or an outdoor part, it is required to improve its resistance to sudden changes in temperature. On the other hand, for example, in some metal/ceramic bonded substrate products in which the metal is bonded to the ceramic substrate by brazing solder, the performance can be further improved by designing the cross-sectional shape of the edge portion of the circuit pattern.

In order to improve the reliability of properties such as resistance to sudden changes in temperature by brazing solder, it is known that extending the brazing solder at the edge portion of the metal sheet can effectively relax the thermal expansion between the metal and the ceramic during the bonding process. Thermal stress due to coefficient difference. For example, Japanese Laid-Open Patent No. 10-326949 proposes a substrate having a structure in which the difference in size between the bottom surface and the top surface of the peripheral portion of the metal circuit board is 50-100 micrometers (the difference is determined by The distance between the plane perpendicular to the main plane of the metal sheet at one end of the bottom surface of the metal sheet and the plane perpendicular to the main surface of the metal sheet passing through the top surface of the metal sheet on the same side as the above-mentioned end of the bottom surface of the metal sheet, that is, L1 in Figure 5 (If the area of the bottom surface is greater than the area of the top surface, this value is considered to be +, and this distance is referred to as the "skirt extension length" below), protruding from the interface of the metal sheet and the brazing solder bonded thereto The length of the brazing solder (this length is represented by L2 among Fig. 5), and this length is referred to as " brazing solder layer second-out length " below, is-50—+30 micron.In addition, Japanese patent 2797011 proposes a A substrate having a structure in which the length of the brazing solder protruding from the interface between the metal sheet and the brazing solder bonded thereto is 250 micrometers or more.

However, even if the length of the brazing solder protruding from the interface between the metal sheet and the brazing solder bonded thereto is -50 to +30 micrometers, it is not possible to obtain a temperature shock resistance sufficient to meet market requirements. If the length of the brazing solder protruding from the interface between the metal sheet and the brazing solder adhered thereto is 250 µm or more, sufficiently high resistance to sudden changes in temperature can be obtained. However, in recent years, in the market trend of emphasizing miniaturization and flexibility, if the length of brazing solder sticking out is very long, it is difficult for the outer dimension of the substrate to meet the design requirements, so it is necessary to provide, even if the outer dimension is smaller, it will Resistance to sudden temperature changes comparable to that of the case with an overhang length of 250 µm.

Overview of the invention

Therefore, it is an object of the present invention to avoid the above-mentioned problems and to provide a metal/ceramic bonded product which can ensure sufficient resistance to sudden changes in temperature, has a substrate with small external dimensions, and which is both highly reliable and miniaturized. of.

In order to achieve the above and other objects, the present inventors conducted serious research and found that by optimally controlling the protruding length of the brazing solder layer so that a larger component mounting area can be designed, a metal/ceramic A bonded article which ensures sufficient resistance to sudden changes in temperature and has a substrate with small external dimensions, and which is highly reliable and compact. As a result, the present inventors have accomplished the present invention.

According to one aspect of the present invention, there is provided a metal/ceramic bonded article comprising a ceramic substrate and a metal sheet bonded to the ceramic substrate by a brazing solder, wherein the brazing solder protrudes from the bottom surface of the metal sheet by a length of Longer than 30 microns, 250 microns or less.

According to another aspect of the present invention, there is provided another metal/ceramic bonded article comprising a ceramic substrate and a metal sheet bonded to the ceramic substrate by a brazing solder, wherein the brazing solder layer extends from the bottom surface of the metal sheet. The out length is 25% or more of the sheet metal thickness.

In each of the above metal/ceramic bonded articles, the length of the projected portion of the brazing solder layer may be 50 to 200 micrometers. Imagine two planes, one is the plane perpendicular to the main plane of the metal sheet passing through one end of the bottom surface of the metal sheet, and the other is a plane perpendicular to the main plane of the metal sheet passing through the top surface of the metal sheet on the same side as the above-mentioned end of the bottom surface of the metal sheet plane, the distance between these two planes may be 50 microns or less, and the distance is considered to be + when the bottom surface area is greater than the top surface area. The ceramic matrix may be formed from a material selected from oxides, nitrides and carbides. The metal sheet can be formed of a material selected from copper, aluminum, an alloy mainly composed of copper, and an alloy mainly composed of aluminum. Brazing solders can contain silver and reactive metals. The brazing solder may include aluminum. The metal sheet and the brazing solder layer may be treated with at least one of nickel plating, nickel alloy plating, gold plating, and protective treatment.

Brief description of the drawings

The present invention can be more fully understood from the following detailed description and the accompanying drawings showing preferred embodiments of the invention. However, the drawings are not meant to limit the invention to the particular embodiments described, but they serve only to illustrate and illustrate the invention.

In the attached picture,

1A-1C are cross-sectional views illustrating the steps of manufacturing the metal/ceramic bonded article of the present invention;

2A-2C are cross-sectional views illustrating the steps of manufacturing the metal/ceramic bonded article of the present invention;

3A-3C are cross-sectional views illustrating the steps of manufacturing the metal/ceramic bonded article of the present invention;

4A-4C are cross-sectional views illustrating the steps of manufacturing the metal/ceramic bonded article of the present invention;

Figure 5 is a schematic diagram illustrating the length of the skirt extension and the length of the brazing solder layer sticking out;

Fig. 6 is a photomicrograph showing a section of a metal/ceramic bonded article obtained in Example 1;

Fig. 7 is the relationship figure of brazing solder layer protruding length (micron) and the tolerance (number of times) by furnace in embodiment and comparative example;

Fig. 8 is a graph showing the relationship between the protruding length (micrometer) and the bending strength (MPa) of the brazing solder layer in Examples and Comparative Examples.

Detailed Description of the Preferred Embodiment

Preferred embodiments of the metal/ceramic bonded article of the present invention are described below with reference to the accompanying drawings.

A preferred embodiment of the metal/ceramic bonded article of the present invention comprises a ceramic substrate and a metal sheet bonded to the ceramic substrate by a brazing solder, wherein the brazing solder layer extends from the bottom surface of the metal sheet to a length greater than 30 microns , is 250 microns or less, preferably 50-200 microns, or the length of the brazing solder layer protruding from the bottom surface of the metal sheet is 25% or more of the thickness of the metal sheet, preferably 30% or more.

In the case of a metal circuit sheet with a thickness of about 0.25-0.4mm usually used in a power module, when the brazing solder layer protruding length increases, the stress caused by the peripheral part of the metal circuit board during the period of experiencing a sudden change in temperature is caused The deterioration degree of the matrix strength is improved, and if the brazing solder layer protrudes 30 microns or more, preferably 50 microns or more, sufficient resistance to sudden temperature changes can be obtained. If the protruding length of the brazing solder layer is set to the maximum length allowed by the design size of the substrate, high resistance to sudden changes in temperature can be obtained.

If the thickness of the metal wiring sheet is about 0.15mm or thinner, the stress on the matrix generated during the thermal expansion and contraction of the metal is reduced. It is also possible to maintain the temperature abrupt change resistance if the length protruding from the interface is less than 30 μm. The protruding length of the brazing solder layer is preferably 25% or more of the thickness of the metal wiring portion, more preferably 30% or more. High resistance to sudden changes in temperature can be obtained if the protruding length of the brazing solder layer is set to the maximum length allowed by the size of the substrate.

Regarding the materials used for the ceramic matrix of the present _invention , _Al2O3 (aluminum oxide) is characterized by being cheap, AlN is _{characterized} by high thermal conductivity despite being expensive, _Si3N4 and SiC are characterized by high strength, Toughness is also high. According to the characteristics of these ceramic substrates, Al ₂ O ₃ can form inexpensive ceramic circuit boards, and AlN can use its good radiation performance to form ceramic circuit boards suitable for semiconductors with high calorific value, such as high-power chips, Si ₃ N ₄ and SiC can take advantage of their good strength to form high resistance to sudden changes in temperature and high environmental resistance, which can be used in harsh environments, such as ceramic circuit boards in automobiles.

The brazing solder used to bond the metal sheet to the ceramic substrate can be selected based on the physical properties of the metal of the metal sheet and the ceramic of the ceramic substrate. If the metal sheet is a copper sheet, and if the ceramic substrate is an AlN matrix or _{an Al2O3} matrix, the metal composition of the brazing solder preferably contains 65-99% by weight Ag, 1-10% by weight active metal, and the balance being essentially Cu. At least one element selected from Ti or Zr can be added as an active metal, and a small amount of a fourth component such as _TiO2 can be added for stress relaxation. The brazing solder can be located on the entire surface of the ceramic substrate or only in some predetermined locations. Therefore, if necessary, the brazing solder can be selectively used according to its use. The brazing solder to be used may be in any form such as paste or foil. If the metal flakes are aluminum flakes, the metal component of the brazing solder preferably contains mainly aluminium, eg Al-Si or Al-Si-Ti, the form being unimportant, eg paste or foil.

As the metal sheet, a copper sheet is often used in view of its good electrical conductivity. Usually, a method is used to cover the metal sheet with a resist and then etch it to form a predetermined circuit pattern.

As a chemical substance for removing unnecessary parts such as brazing solder, a chemical substance that dissolves brazing solder, such as fluoride or chelate, can be used because ferric chloride or copper chloride, hydrochloric acid, and hydrogen peroxide that are generally used The mixed solution cannot sufficiently dissolve the brazing solder, etc.

Since the brazing solder layer protruding length is zero or very short after chemical substances are used to remove unnecessary portions of the brazing solder etc., further processing is required to obtain the desired brazing solder layer protruding length. As a method of obtaining the required protrusion length of such a brazing solder layer, for example, it is possible to apply a resist having a size slightly smaller than that of the etched metal sheet on the surface of the circuit pattern, and then dissolve the metal by etching or chemical polishing. sheet to obtain the desired length of brazing solder layer protrusion. In addition, the protruding length of the brazing solder layer can also vary greatly depending on the conditions of being etched or chemically polished, and can also be controlled by conditions such as temperature and spraying pressure. As another method to obtain the required length of the brazing solder layer, it is also possible to form a soldering material with a certain pattern shape on the ceramic substrate by printing or the like. The patterned shape is expected to achieve the desired length of brazing solder layer protrusion, and the brazing solder is then used to bond the metal sheet, which has been stamped or etched into a patterned shape, to the ceramic substrate. But the present invention should not be limited to these methods.

With regard to the dimensions of the bottom surface and the top surface of the metal circuit part, it is advantageous that the area of the top surface on which the Si chip will be located is larger. However, it is difficult to form small dimensional differences by the etching method generally performed. In order to prevent the possibility of increased discharge to adjacent metal circuit parts, the size between the top surface and the bottom surface is preferably a negative size difference (the area of the top surface is larger than the area of the bottom surface), and the discharge does not occur. To an extent, this size difference is 40 microns or less. This range is achieved by varying the etch process and/or etch conditions.

In order to improve the weather resistance of the metal to be formed as a circuit pattern on the metal/ceramic bonded circuit board and to prevent its solder wettability from deteriorating over time, nickel plating, nickel alloy plating, gold plating, or shielding treatment is preferably performed. The process of metal plating is, for example, carried out by a common electroless plating method, which uses hypophosphite-containing chemical substances as Ni-P chemical substances after degreasing, chemical polishing and pretreatment with Pd-activated chemical substances. electroless plating with a plating solution; or a method of electroplating by contacting an electrode to a pattern. In addition, it is also preferred to carry out protective treatment with usual azocene compounds.

On the metal circuit sheet of the metal/ceramic bonded circuit board made according to the present invention, electrical components and electronic components such as semiconductor chips and resistors are soldered by soldering or the like and heat sinks are soldered on the back side thereof by soldering or the like. Solder it. In addition, the following steps are performed: gluing the plastic case, etc., connecting the external connectors to the circuit board with wires for ultrasonic bonding, injecting insulating gel, attaching the top cover, and finally forming a module.

Embodiments of the metal/ceramic bonded article of the present invention will be described in detail below with reference to the accompanying drawings.

Example 1

The metal powder containing metal components was weighed such that the components were: 91 wt% silver, 7 wt% copper, 1.5 wt% Ti, 0.5 wt% _TiO2 . To this metal powder was added about 10% acrylic carrier. Using an automatic mortar and three roller mills, the mixture was kneaded in the usual way to prepare a pasty brazing solder.

Next, as shown in FIGS. 1A-1C, a ceramic substrate 10 (FIG. 1A) is fabricated, and brazing solder 12 is applied on both sides of the ceramic substrate 10 by screen printing (FIG. 1B). Then, a copper sheet 14 with a thickness of 0.25 mm was placed on both sides thereof, and the copper sheet 14 was bonded to the ceramic substrate 10 in a vacuum furnace at 835°C. In order to check the thickness of the brazing solder layer 12, the thus bonded sample was cut, and the thickness of the brazing solder layer 12 was measured. The result is a brazing solder layer 12 having a thickness of approximately 20 microns. As the ceramic substrate 10, an S-grade AlN substrate manufactured by ATG Corporation was used.

Then, the thus bonded samples were taken out from the vacuum furnace. Next, as shown in FIGS. 2A-2C , a UV-cured alkaline lift-off resist 16 ( FIG. 2A ) is applied on both sides of the bonded copper sheet 14 with the desired circuit pattern and a thickness of 10-15 microns. Unnecessary portions of the copper sheet 14 are removed with an etchant containing copper chloride, hydrogen peroxide, and hydrochloric acid (FIG. 2B). After that, the resist 16 was removed with a 3.5% aqueous sodium hydroxide solution (FIG. 2C).

Then, in order to remove unnecessary brazing solder parts between the circuit patterns and on the edge face of the substrate, the sample was immersed in a mixed solution containing 1.4% EDTA, 6% hydrogen peroxide and 3% ammonia to remove unnecessary brazing solder 12 part (Figure 3A). Then, on both sides of the copper sheet 14, apply a UV-curable alkaline stripping resist 18 (FIG. 3B) with a desired circuit pattern again, and etch the copper with an etchant containing cupric chloride, hydrogen peroxide and hydrochloric acid. Slice 14 for 15 minutes (Figure 3C). Then, the resist 18 was removed with a 3.5% sodium hydroxide aqueous solution (FIG. 4A), and Ni-P electroless plating was performed to obtain a plating layer 20 (FIG. 4B).

Figure 6 shows a photomicrograph of a section of the metal/ceramic bonded article thus obtained. For the metal/ceramic bonded article obtained in this example, the brazing solder layer protrusion length and the skirt extension length of the metal circuit portion were measured so that the lengths were 102 microns and <0 microns, respectively. For the metal/ceramic bonded article obtained in this example, a furnace-through treatment (after heating the article at 370° C. for 10 minutes in a reducing atmosphere (nitrogen 4 + hydrogen 1 ) to cool it down) was carried out using Tolerance (number of times) to evaluate reliability. That is, after the furnace treatment, it was visually inspected whether or not cracks occurred in the ceramic part, and the number of times of the furnace treatment just before the number of times of the furnace treatment that caused the crack was taken as the tolerance (number of times) of the furnace. This resistance through the oven was used to evaluate the reliability of the metal/ceramic bonded articles. As a result, the through-the-oven resistance of the metal/ceramic bonded article made in this example was 58.

Example 2

In the same manner as in Example 1, a metal/ceramic bonded article having a brazing solder layer protruding length of 101 µm and a skirt extension length of the metal circuit portion <0 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 58.

Example 3

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer protruding length of 95 µm and a skirt extension length of the metal circuit portion of 3 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 68.

Example 4

Except that the second etching was carried out for 20 minutes, all the other steps were the same as in Example 1 to obtain a metal/ceramic bonded product whose brazing solder layer protruding length was 124 microns, and the skirt extension length of the metal circuit part<0 Microns. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 84.

Example 5

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer protruding length of 88 µm and a skirt extension length of the metal circuit portion of 11 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 78. In addition, for the metal/ceramic bonded article obtained in this example, the initial bending strength and the bending strength after passing through the furnace three times were measured using an apparatus for measuring bending strength (SHIMADZUAGS-1000D, produced by Shimadzu Seisakusho), and the measurement condition was that the load The speed was 0.5mm/min and the span length was 30mm. As a result, the initial flexural strength was 615MPa and the flexural strength after three passes through the furnace was 535MPa.

Example 6

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer protruding length of 133 µm and a skirt extension length of the metal circuit portion <0 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 98.

Example 7

Except that the second etching was carried out for 10 minutes, all the other steps were the same as the method described in Example 1 to obtain such a metal/ceramic bonded article, its brazing solder layer protruding length was 73 microns, and the skirt of the metal circuit part The extension length is 8 microns. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 74.

Example 8

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer protruding length of 82 µm and a skirt extension length of the metal circuit portion of 4 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 58. In addition, similar to Example 5, for the metal/ceramic bonded product obtained in this example, the initial flexural strength and the flexural strength after three passes through the furnace were measured. As a result, the initial flexural strength was 609 MPa, and after three passes through the furnace The bending strength is 570MPa.

Example 9

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer protruding length of 83 µm and a skirt extension length of the metal circuit portion of 11 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 42.

Example 10

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer projecting length of 93 µm and a skirt extension length of the metal circuit portion of 5 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 52.

Example 11

In the same manner as in Example 7, a metal/ceramic bonded product having a brazing solder layer protruding length of 65 µm and a skirt extension length of the metal circuit portion of 21 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) to pass through the furnace was 32.

Example 12

In the same manner as in Example 7, a metal/ceramic bonded product having a brazing solder layer projecting length of 53 µm and a skirt extension length of the metal circuit portion of 23 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) to pass through the furnace was 32.

Example 13

In the same manner as in Example 7, a metal/ceramic bonded product having a brazing solder layer projecting length of 62 µm and a skirt extension length of the metal circuit portion of 31 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) to pass through the furnace was 32.

Example 14

In the same manner as in Example 7, a metal/ceramic bonded article having a brazing solder layer protruding length of 54 µm and a skirt extension length of the metal circuit portion of 15 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 40.

Example 15

In the same manner as in Example 7, a metal/ceramic bonded article having a brazing solder layer protruding length of 57 µm and a skirt extension length of the metal circuit portion of 26 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 26.

Example 16

In the same manner as in Example 7, a metal/ceramic bonded article having a brazing solder layer protruding length of 55 µm and a skirt extension length of the metal circuit portion of 25 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) to pass through the furnace was 30.

Example 17

In the same manner as in Example 7, a metal/ceramic bonded product having a brazing solder layer protruding length of 55 µm and a skirt extension length of the metal circuit portion of 26 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) to pass through the furnace was 32.

Example 18

In the same manner as in Example 4, a metal/ceramic bonded product having a brazing solder layer protruding length of 134 µm and a skirt extension length of the metal circuit portion <0 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 92.

Example 19

In the same manner as in Example 7, a metal/ceramic bonded article having a brazing solder layer protruding length of 52 µm and a skirt extension length of the metal circuit portion of 18 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 26. In addition, similar to that described in Example 5, for the metal/ceramic bonded product obtained in this example, the initial flexural strength and the flexural strength after three passes through the furnace were measured. As a result, the initial flexural strength was 622 MPa, and the three passes The bending strength after the furnace is 549MPa.

Example 20

In the same manner as in Example 7, a metal/ceramic bonded product having a brazing solder layer projecting length of 62 µm and a skirt extension length of the metal circuit portion of 10 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 36.

Example 21

In the same manner as in Example 7, a metal/ceramic bonded article having a brazing solder layer protruding length of 62 µm and a skirt extension length of the metal circuit portion of 20 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 38.

Comparative example 1

Except that the second etching was carried out for 5 minutes, other steps were the same as in Example 1, and such a metal/ceramic bonded article was obtained, its brazing solder layer protruding length was -20 microns, and the skirt extension length of the metal circuit part is 45 microns. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the resistance (number of times) to pass through the furnace was 11, which was smaller than that in Examples 1-21. In addition, similar to Example 5, for the metal/ceramic bonded product obtained in this example, the initial flexural strength and the flexural strength after passing through the furnace three times were measured. As a result, the initial flexural strength was 548 MPa, and after three times passing through the furnace The bending strength is 203MPa. Both of these intensities are smaller than in Examples 5, 8 and 19.

Comparative example 2

In the same manner as in Example 1, a metal/ceramic bonded product having a brazing solder layer projecting length of 0 µm and a metal circuit part skirt extending length of 30 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 19, which was smaller than that in Examples 1-21. In addition, similar to Example 5, for the metal/ceramic bonded product obtained in this example, the initial flexural strength and the flexural strength after three passes through the furnace were measured. As a result, the initial flexural strength was 590 MPa, and after three passes through the furnace The bending strength is 331MPa. Both of these intensities are smaller than in Examples 5, 8 and 19.

Comparative example 3

In the same manner as in Example 1, a metal/ceramic bonded article having a brazing solder layer protruding length of 30 µm and a skirt extension length of the metal circuit portion of 15 µm was obtained. For the metal/ceramic bonded product obtained in this example, the treatment of passing through a furnace was carried out, and the reliability was evaluated by the resistance (number of times) of passing through the furnace. As a result, the tolerance (number of times) of passing through the furnace was 25, which was smaller than that in Examples 1-21. In addition, similar to Example 5, for the metal/ceramic bonded product obtained in this example, the initial flexural strength and the flexural strength after three passes through the furnace were measured. As a result, the initial flexural strength was 610 MPa, and after three passes through the furnace The bending strength is 510MPa. Both intensities are smaller than in Examples 5, 8 and 19.

The results of Examples 1-21 and Comparative Examples 1-3 are shown in the table below.

Table 1

Protrusion length (micron) Skirt Extended Length (microns) Resistance to passing through the furnace (number of times) Initial bending strength (MPa) Bending strength after three passes through the furnace (MPa) Example 1 102 <0 58 Example 2 101 <0 58 Example 3 95 3 68 Example 4 124 <0 84 Example 5 88 11 78 615 535 Example 6 133 <0 98 Example 7 73 8 74 Example 8 82 4 58 609 570 Example 9 83 11 42 Example 10 93 5 52 Example 11 65 2 32 Example 12 53 twenty three 32 Example 13 62 31 32 Example 14 54 15 40 Example 15 54 26 26 Example 16 55 25 30 Example 17 55 26 32 Example 18 134 <0 92 Example 19 52 18 26 622 549 Example 20 62 10 36 Example 21 62 20 38

Comparative example 1 -20 45 11 548 203 Comparative example 2 0 30 19 590 331 Comparative example 3 30 15 25 610 510

Figures 7 and 8 show the relationship between the brazing solder layer protrusion length (micrometer) and the tolerance (number of times) through the furnace, and the relationship between the brazing solder layer protrusion length (micrometer) and the bending strength (MPa). relationship between. As shown in Figure 7, if the brazing solder layer protrudes more than about 30 microns, the tolerance (number of times) through the furnace increases rapidly, and if the brazing solder layer protrudes more than about 130 microns, then the pass The furnace's tolerance to changes is reduced. In addition, as shown in FIG. 8, if the brazing solder layer protrudes more than about 30 microns, the difference between the initial bending strength and the bending strength after three passes through the furnace becomes small. From this, it can be seen that if the brazing solder layer extends beyond about 30 microns, the temperature shock resistance is greatly improved.

Although the invention has been described in terms of preferred embodiments in order to facilitate a better understanding of the invention, it should be understood that the invention can be implemented in various ways without departing from the principles of the invention. It will thus be understood that the invention includes all possible embodiments and modifications of the described embodiments which can embody the invention without departing from the principle of the invention as described in the appended claims.

Claims (6)

1. metal/ceramic adhesive article, it comprises:

Ceramic base material;

Sheet metal, it is bonded on the described ceramic base material with brazing solder;

Wherein the brazing solder layer is the 50-200 micron from the length that the basal surface of described sheet metal stretches out;

By sheet metal basal surface one end perpendicular to the plane of sheet metal principal plane, and is 50 microns or littler by sheet metal top surface one end of the above-mentioned end same side of sheet metal basal surface perpendicular to the distance between the plane of sheet metal principal plane, when bottom surface area during greater than top surface area, this distance think on the occasion of.

2. metal/ceramic adhesive article as claimed in claim 1 is characterized in that described ceramic substrate is formed by the material that is selected from oxide, nitride and carbide.

3. metal/ceramic adhesive article as claimed in claim 1 is characterized in that described sheet metal forms by being selected from following material: copper, and aluminium, copper are the alloy of main component, aluminium is the alloy of main component.

4. metal/ceramic adhesive article as claimed in claim 1 is characterized in that described brazing solder contains silver and reactive metal, and described reactive metal is selected from: Ti or Zr.

5. metal/ceramic adhesive article as claimed in claim 1 is characterized in that described brazing solder comprises aluminium.

6. metal/ceramic adhesive article as claimed in claim 1, it is characterized in that described sheet metal and brazing solder through nickel plating, nickel plating alloy and gold-plated at least a mode handle.

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