JP2008205253A - Circuit device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure bonding strength of a metal lead to a ceramic substrate, and to prevent the metal lead from peeling off, as much as possible, in a circuit device configured by connecting the metal lead with a metallic circuit layer on a ceramic substrate through welding. <P>SOLUTION: Holes 11 are made on one face of the ceramic substrate 10, a conductor ball 30 electrically connected with the metallic circuit layer 20 is provided on the holes 11, while part of the conductor ball 30 enters the holes 11, a metal lead 40 is arranged above the conductor ball 30; and the conductor ball 30 and the metal lead 40 are welded. Due to anchor effect and the part of the conductor ball 30 entering the holes 11, the bonding strength of the conductor ball 30 with the ceramic substrate 10 is secured, and also the bonding strength of the conductor ball 30 with the metal lead 40 is secured through weldings. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a circuit device in which a metal lead is connected by welding to a metal circuit layer on a ceramic substrate made of ceramic, and a method for manufacturing such a circuit device.

  Conventionally, as this type of circuit device, one having a ceramic substrate made of ceramic, a metal circuit layer formed on one surface of the ceramic substrate, and a metal lead electrically connected to the metal circuit layer has been proposed. (For example, refer to Patent Document 1).

Here, conventionally, the metal circuit layer on the ceramic substrate and the metal lead are directly connected by ultrasonic welding. When metal leads are connected by ultrasonic welding, there are advantages such that there is little influence of heat because they are connected by plastic flow between members, and electrical loss as a circuit board can be reduced.
JP 2002-9190 A

  However, when ultrasonic welding the metal circuit layer and the metal lead, although there is little thermal shock at the interface between the ceramic substrate and the metal circuit layer, the ceramic substrate is compared with the bonding strength at the interface between the metal circuit layer and the metal lead. The bonding strength at the interface between and the metal circuit layer is very weak. Therefore, there is a problem that the latter interface peels off reliably and the metal leads are easily peeled off from the ceramic substrate.

  The present invention has been made in view of the above problems, and in a circuit device in which a metal lead is connected to a metal circuit layer on a ceramic substrate by welding, the bonding strength of the metal lead to the ceramic substrate is ensured. The purpose is to prevent lead peeling as much as possible.

  In order to achieve the above object, according to the present invention, a hole (11) opened on one surface of the ceramic substrate (10) is provided, and a part of the hole (11) is formed on the hole (11). ) A conductor (30) that is electrically connected to the metal circuit layer (20) is provided in a state in which the metal lead (40) is inserted, and a metal lead (40) is disposed on the conductor (30), and the conductor (30) and the metal lead are arranged. (40) is welded as a first feature.

  According to this, when a part of the conductor (30) enters the hole (11), the anchoring effect thereby secures the bonding strength between the conductor (30) and the ceramic substrate (10), and the conductor (30 30) and the metal lead (40) are joined by welding. Therefore, according to the present invention, it is possible to secure the bonding strength of the metal lead (40) to the ceramic substrate (10) and to prevent the metal lead (10) from peeling off as much as possible.

  Here, the welding of the conductor (30) and the metal lead (40) is preferably performed by laser welding or electron beam welding. In ultrasonic welding, the metal lead (40) in a free state resonates and is difficult to weld. However, if non-contact welding such as laser welding or electron beam welding is employed, such a problem can be avoided.

  When the conductor (30) and the metal lead (40) are welded by laser welding or electron beam welding, the metal lead (40) and the conductor ( 30) and the melted part (50) formed by melting the metal lead (40) from the surface of the metal lead (40) opposite to the conductor (30) to the conductor (30) through the inside of the metal lead (40), It can be formed continuously (see FIG. 1 and the like described later).

  If the inner surface of the hole (11) is roughened, the anchor effect of the inner surface of the hole (11) is further improved (see FIG. 6 described later).

  Also, an active metal layer (13) made of active metal is provided on the inner surface of the hole (11), and the active metal layer (13) and the portion of the conductor (30) that has entered the hole (11) are in close contact with each other. As a result, the adhesion strength between the conductor (30) and the ceramic substrate (10) is improved (see FIG. 7 described later).

  Moreover, you may make the conductor (30) contain Ti which is an active metal. Also in this case, the adhesion strength between the conductor (30) and the ceramic substrate (30) is improved.

  Further, although the number of the hole portions (11) may be one, the above-described anchor effect can be further improved by using a plurality of holes (11).

  Moreover, you may provide the lead support part (60-62) which supports a metal lead (40) to a ceramic substrate (10) in parts other than the welding part of a conductor (30) and a metal lead (40) ( (See FIGS. 8 to 10 described later). According to this, the metal lead (40) is supported by the ceramic substrate (10) at a site other than the welded portion, which is preferable in terms of securing the bonding strength of the metal lead (40).

  Further, if a positioning portion (70, 71) for positioning the metal lead (40) with respect to the ceramic substrate (10) is provided on at least one of the ceramic substrate (10) and the metal lead (40), the metal lead ( 40) is easily positioned when attached to the ceramic substrate (10) (see FIGS. 11 and 12 described later).

  Moreover, if the stress relieving part (80) which relieves the stress added to the welding part of a conductor (30) and a metal lead (40) is provided in a metal lead (40), the stress added to a welding part will be relieved, and metal This is preferable in terms of securing the bonding strength of the lead (40) (see FIG. 13 described later).

  Further, according to the present invention, as a method of manufacturing a circuit device, a metal circuit layer (20) and a hole (11) opened in the one surface are provided on one surface of the ceramic substrate (10), and then the hole (11 After the conductor (30) is placed on top of and the electrical connection between the conductor (30) and the metal circuit layer (20), the metal lead (40) is mounted on the conductor (30). The second feature is to perform welding between the conductor (30) and the metal lead (40) (see FIG. 4 described later).

  Further, according to the present invention, as a method of manufacturing a circuit device, a metal circuit layer (20) and a hole (11) opened on the one surface are provided on one surface of a ceramic substrate (10), and then a conductor (30). Of the conductor (30) over the hole (11), the electrical connection between the conductor (30) and the metal circuit layer (20), and the conductor (30) And the metal lead (40) is a third feature (see FIG. 5 described later).

  Here, in the manufacturing method having the second feature, after the conductor (30) is provided on the ceramic substrate (10) side, the metal lead (40) is attached to the conductor (30). In the method, the conductor (30) is previously attached to the metal lead (40), and then the conductor (30) is attached to the ceramic substrate (10) side.

  As described above, in both the manufacturing methods, the mounting order of the ceramic substrate (10), the conductor (30), and the metal lead (40) is different, but the manufacturing method having the second feature and the manufacturing method having the third feature are used. Accordingly, the circuit device having the first feature can be appropriately manufactured.

  Further, according to the present invention, as a method of manufacturing a circuit device, a ceramic substrate (10) having a hole (11) opened on one surface is prepared, and the hole (11) is formed on one surface of the ceramic substrate (10). The metal lead (40) is disposed on the metal lead (40) and the metal circuit layer (20) in contact with each other, and then the metal lead (40) and the metal circuit layer (20) are joined by welding. At the same time, a fourth feature is that a part of the metal lead (40) melted by the welding is inserted into the hole (11) (see FIG. 15 described later).

  According to this, since a part of the metal lead (40) enters the hole (11), the anchoring effect thereby secures the bonding strength between the metal lead (40) and the ceramic substrate (10). Even without using the conductor as described above, it is possible to secure the bonding strength of the metal lead (40) to the ceramic substrate (10) and to prevent the peeling as much as possible.

  In the case of the manufacturing method having the fourth feature, the conductor (30) and the metal lead (40) can be welded by laser welding or electron beam welding.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
FIG. 1 is a diagram showing a schematic cross-sectional configuration of a circuit device 100 according to a first embodiment of the present invention, FIG. 2 is a unit configuration diagram of a ceramic substrate 10 in FIG. 1, and FIG. 2 is a diagram illustrating a schematic planar configuration on one surface of a ceramic substrate 10 in the apparatus 100. FIG. In FIG. 3, the metal lead 40 and the conductor ball 30 are shown by broken lines in order to show the positional relationship with the ceramic substrate 10.

  The circuit device 100 generally includes a ceramic substrate 10 made of ceramic, a metal circuit layer 20 formed on one surface of the ceramic substrate 10, and metal leads electrically connected to the metal circuit layer 20 via conductors 30. 40.

  The ceramic substrate 10 is a wiring substrate made of a ceramic such as alumina or silicon nitride. The ceramic substrate 10 may be a single layer substrate or a multilayer substrate in which a plurality of ceramic layers are stacked. Such a ceramic substrate 10 can be formed by firing a green sheet in the same manner as a general ceramic substrate.

  The metal circuit layer 20 is formed on one surface of the ceramic substrate 10. The metal circuit layer 20 is configured as a part of wiring in the ceramic substrate 10 as a wiring substrate. The metal circuit layer 20 is made of, for example, a thick film formed of a conductive paste such as Au (gold), Ag (silver), Cu (copper), W (tungsten), Mo (molybdenum), or a plating film. It is configured.

  Here, as shown in FIGS. 1 to 3, a hole portion 11 is provided on one surface of the ceramic substrate 10 so as to open to the one surface. The number of the holes 11 may be one, but a plurality of holes 11 are provided here. The hole 11 can be formed by drilling or the like at the stage of the green sheet when forming the ceramic substrate 10, or can be formed by drilling by laser or cutting after the ceramic substrate 10 is fired.

Here, the hole portion 11 has a round hole shape, and is disposed in a portion of the one surface of the ceramic substrate 10 where the metal circuit layer 20 is located, that is, inside the metal circuit layer 20 and also outside the metal circuit layer 20. Has been. For example, the diameter of one hole 11 is preferably 0.1 mm to 0.3 mm, and the depth is preferably 0.2 mm to 0.6 mm. Further, the holes 11 are a plurality arranged in this manner, the arrangement density is preferably 1 / mm ² to 2 pieces / mm ^2.

  A conductor ball 30 as a conductor is provided on the hole 11 on one surface of the ceramic substrate 10. The conductor ball 30 is made of a conductor material such as Au or Cu disposed by a wire bonding method or solder disposed by a printing method or the like. It has a shape like this.

  Here, the conductor ball 30 is disposed on the hole 11 by utilizing heating / pressurization by wire bonding method, fluidity of solder, or the like, so that a part of the conductor ball 30 enters the hole 11. It is in a state. The conductor ball 30 is in contact with and electrically connected to the metal circuit layer 20 with a part of the conductor ball 30 biting into the hole 11.

  Here, the hole 11 may be formed as a via hole provided in a general ceramic substrate. At this time, the inner surface of the hole 11, the metal circuit layer 20, and the conductor ball 30 may be formed of Cu, Au, or It is preferable to use the same metal such as an alloy including any one of them.

  Further, the metal lead 40 is disposed on the conductor ball 30, and the conductor ball 30 and the metal lead 40 are welded and electrically connected. The metal lead 40 is made of a plate material such as Cu, Cu alloy, or Fe alloy. Although not shown, it is desirable that the surface of the metal lead 40 be plated with Sn, Ni, Cu, Au, Pd, etc., considering the bonding property with the conductor ball 30.

  Here, in this embodiment, welding of the conductor ball 30 and the metal lead 40 is performed by laser welding or electron beam welding. These laser welding and electron beam welding can employ general welding methods.

  Therefore, as shown in FIG. 1, in the welded portion between the conductor ball 30 and the metal lead 40, the melted portion 50 in which the metal lead 40 and the conductor ball 30 are melted together is the conductor ball 30 in the metal lead 40. It is formed continuously from the surface located on the opposite side to the conductor ball 30 through the inside of the metal lead 40.

  Thus, the metal lead 40 is electrically connected to the metal circuit layer 20 via the conductor ball 30, and the metal lead 40 is electrically connected to an external wiring member (not shown). ing. Thereby, the circuit device 100 and the outside are electrically connected through the metal lead 40.

  In the circuit device 100 of this embodiment, mounting parts such as an IC chip, a resistance element, and a capacitor element (not shown) are mounted on the ceramic substrate 10. These mounted components constitute a circuit in the circuit device 100 together with the metal circuit layer 20, and the circuit device 100 can be electrically exchanged with the outside through the metal lead 40.

  Next, a method for manufacturing the circuit device 100 of this embodiment will be described with reference to FIG. FIG. 4 is a process diagram showing a method of manufacturing the circuit device 100, and shows a cross section of a work in each process.

  First, as shown in FIG. 4A, a first step of preparing the ceramic substrate 10 is performed. The ceramic substrate 10 has a metal circuit layer 20 formed on one surface thereof by the above-described thick film, plating, or the like, and a hole portion 11 formed by the above-described drilling process or the like.

  After performing this first step, the second step is performed. First, the conductor ball 30 is disposed on the hole 11 on one surface of the ceramic substrate 10 by using a method such as wire bonding or solder printing described above.

  At this time, as shown in FIG. 4A, the conductor ball 30 and the metal circuit layer 20 are electrically connected by these methods in a state where a part of the conductor ball 30 enters the hole 11. . In this way, the conductor ball 30 is arranged on the hole 11 and the conductor ball 30 and the metal circuit layer 20 are electrically connected.

  Further, in the second step, next, as shown in FIG. 4B, the metal lead 40 is mounted on the conductor ball 30. At this time, the metal lead 40 may be simply placed on the conductor ball 30 but may be thermocompression-bonded.

  Next, in the second step, the conductor ball 30 and the metal lead 40 are welded by laser welding or electron beam welding. At this time, the laser or electron beam is applied to the surface of the metal lead 40 opposite to the conductor ball 30 (the upper surface of the metal lead 40 in FIG. 4C).

  As a result, the melting portion 50 in which the conductor ball 30 and the metal lead 40 are melted as shown in FIG. 4C is formed, and the both 30 and 40 are joined. Thus, the second step is completed, and in this embodiment, the ceramic substrate 10, the metal circuit layer 20 formed on one surface of the ceramic substrate 10, and the metal lead 40 electrically connected to the metal circuit layer 20. The circuit device 100 having the above is completed.

  By the way, according to the present embodiment, the hole 11 opened on the one surface is provided on one surface of the ceramic substrate 10, the conductor ball 30 is provided on the hole 11, and the conductor ball 30 and the metal circuit layer 20 are connected. In addition to being electrically connected, a part of the conductor ball 30 is made to enter the hole 11, and the metal lead 40 is disposed on the conductor ball 30, and the conductor ball 30 and the metal lead 40 are welded. is doing.

  According to this, a part of the conductor ball 30 enters the hole 11, that is, the conductor ball 30 bites into the ceramic substrate 10, whereby the anchor effect is exerted, and the conductor ball 30 and the ceramic substrate 10. And bonding strength is ensured. At the same time, the bonding strength of the conductor ball 30 and the metal lead 40 is ensured by welding.

  As described above, according to the present embodiment, the metal lead 40 and the metal circuit layer 20 that have been directly connected by ultrasonic welding in the past are connected via the conductor ball 30, so that the metal lead 40 is connected. Bonding strength to the ceramic substrate 10 can be ensured, and peeling of the metal lead 10 can be prevented as much as possible.

  In this embodiment, the conductor ball 30 and the metal lead 40 are welded by laser welding or electron beam welding. In the conventional ultrasonic welding, when the metal lead 40 is welded, the metal lead 40 in a free state resonates due to the ultrasonic wave of the welding and is difficult to weld.

  However, as in this embodiment, if laser welding or electron beam welding is used, the welding jig does not come into contact with the object to be welded or vibration is not applied to the object to be welded. In other words, these laser welding and electron beam welding are non-contact welding, and if these welding methods are adopted, the above-described resonance problem in ultrasonic welding can be avoided, welding is easily performed, and joint reliability is improved. From the viewpoint of sex.

  In addition, the present embodiment has an advantage that the thermal influence of laser welding / electron beam welding can be mitigated by interposing the conductor ball 30 between the metal lead 40 and the metal circuit layer 20 during welding. is there.

  Moreover, a specific example is described about the dimension structure of the welding part for exhibiting the effect of this embodiment appropriately. First, the thickness of the metal lead 40 (the thickness in the vertical direction in FIG. 1) is, for example, about 0.2 mm to 0.5 mm, and the surface of the metal lead 40 is plated with Sn, Ni, or the like. When applied, the thickness of the plating is about 1 μm to 3 μm. The height of the conductor ball 30 is about 0.5 mm to 1 mm, and the thickness of the metal circuit layer 20 is about 0.01 mm to 0.03 mm.

  Further, in the example shown in FIG. 3, the holes 11 are arranged in both the part of the one surface of the ceramic substrate 10 where the metal circuit layer 20 is located and the part outside the metal circuit layer 20. .

  Here, in view of the effect of the hole 11 described above, the hole 11 may be provided only on a portion of the one surface of the ceramic substrate 10 where the metal circuit layer 20 is located, or outside the metal circuit layer 20. It may be provided only in this part. That is, it is only necessary that the hole 11 is disposed so that the conductor ball 30 is in contact with and electrically connected to the metal circuit layer 20 and partly enters the hole 11.

(Second Embodiment)
FIG. 5 is a process diagram showing a method of manufacturing the circuit device 100 according to the second embodiment of the present invention, and shows a cross section of a workpiece in each process. The manufacturing method of the present embodiment finally manufactures a circuit device 100 similar to that shown in the first embodiment, but is a modification of the procedure in the second step.

  In the method for manufacturing the circuit device 100 shown in FIG. 4, the ceramic substrate 10 is prepared in the first step, and in the subsequent second step, the conductor balls 30 are provided on the ceramic substrate 10 side, and then the conductor balls 30 are formed. A metal lead 40 was mounted.

  On the other hand, in the manufacturing method of this embodiment, the ceramic substrate 10 having the metal circuit layer 20 and the hole 11 on one surface is prepared in the first step, and in the subsequent second step, FIG. As shown in FIG. 2, the conductor ball 30 is attached to the metal lead 40 in advance before the conductor ball 30 is disposed on the hole 11 and the metal circuit layer 20.

  The conductor ball 30 can be attached to the metal lead 40 by using a technique such as wire bonding or solder printing described above. In the second step, thereafter, as shown in FIG. 5B, the conductor ball 30 attached to the metal lead 40 is mounted on the hole 11 and the metal circuit layer 20.

  The conductor ball 30 is mounted by thermocompression bonding, so that the conductor ball 30 and the metal circuit layer 20 are electrically connected in a state where a part of the conductor ball 30 enters the hole 11. In this way, the conductor ball 30 is arranged on the hole 11 and the conductor ball 30 and the metal circuit layer 20 are electrically connected.

  Furthermore, also in the second step of this manufacturing method, as shown in FIG. 5C, the conductor ball 30 and the metal lead 40 are welded by laser welding or electron beam welding. Thus, the second step is completed, and the circuit device 100 similar to the above is completed also in this embodiment. The circuit device 100 according to this embodiment also exhibits the same effect as that of the first embodiment.

(Third embodiment)
FIG. 6 is a diagram showing a schematic cross-sectional configuration of a circuit device 101 according to the third embodiment of the present invention. The circuit device 101 of the present embodiment is different from the circuit device of the first embodiment in that “the inner surface of the hole 11 is roughened”.

  As shown in FIG. 6, the inner surface of the hole 11 is configured as a roughened portion 12 as a roughened surface. The roughened portion 12 can be formed by, for example, a general technique of forming a roughened Ni plating or forming a plated film of Cu or the like and performing rough etching on the film. .

  According to the present embodiment, in addition to the effects described in the first embodiment, the anchor effect of the inner surface of the hole 11 is further improved, and further improvement in the bonding strength between the conductor ball 30 and the ceramic substrate 10 is expected. . Therefore, as a result, it is expected that the bonding strength of the metal lead 40 to the ceramic substrate 10 can be secured more firmly.

(Fourth embodiment)
FIG. 7 is a diagram showing a schematic cross-sectional configuration of a circuit device 102 according to the fourth embodiment of the present invention. The circuit device 102 according to the present embodiment is different from the circuit device according to the first embodiment in that “the active metal layer 13 is provided on the inner surface of the hole 11 and made of active metal”.

  The active metal layer 13 is formed by depositing a metal selected from active metals such as Ti, Zr, and Hf on the inner surface of the hole 11 by general vacuum deposition or the like. Such an active metal functions as a surfactant in brazing or the like.

  This vapor deposition is performed after the hole 11 is formed by the above-described drilling process, whereby the active metal layer 13 is formed on the inner surface of the hole 11. Thereafter, the conductor balls 30 may be disposed in the hole 11 and the metal circuit layer 20 in the same manner as described above. The active metal layer 13 and the portion of the conductor ball 30 that has entered the hole 11 are in close contact with each other.

  According to the present embodiment, in addition to the effects described in the first embodiment, these active metal layers 13 exhibit the action of a surfactant in brazing, so that the conductive ball 30 and the ceramic substrate 10 are in close contact with each other. Further improvement in strength can be expected.

(Fifth embodiment)
In the fourth embodiment, the active metal is provided on the hole 11 side of the ceramic substrate 10, but Ti, which is the active metal, may be provided on the conductor ball 30 side. That is, the “conductor ball 30 may contain Ti” may be used.

  Specifically, an alloy of Cu and Ti constituting the conductor ball 30 is produced. For example, a Cu alloy to which Ti is added by 1 wt% to 3 wt% is manufactured, this alloy is processed as a wire, and this is formed as a conductor ball 30 on one surface of the ceramic substrate 10 by a wire bonding method.

  Also in this case, Ti, which is an active metal, exerts the action of a surfactant in brazing, so that the adhesion strength between the conductor ball 30 and the ceramic substrate 10 is improved. In addition, since this embodiment is the structure which makes the conductor ball | bowl 30 contain Ti, it is applicable to each above-mentioned embodiment. That is, this embodiment may be used in combination with the configuration of the fourth embodiment having the active metal layer 13.

(Sixth embodiment)
FIG. 8 is a diagram showing a schematic cross-sectional configuration of a circuit device according to the sixth embodiment of the present invention. The circuit device according to this embodiment is different from the circuit device according to the first embodiment in that the “lead support portion 60” is added.

  As shown in FIG. 8, the lead support portion 60 supports the metal lead 40 on the ceramic substrate 10 at a portion other than the welded portion between the conductor ball 30 and the metal lead 40. Here, the lead support portion 60 is provided on the metal lead 40 side, and is configured as a protrusion 60 integrally formed with the metal lead 40 and extending to one surface side of the ceramic substrate 10.

  And since the projection part 60 as this lead support part is interposed between the metal lead 40 and the ceramic substrate 10 and supports the metal lead 40, the metal lead 40 is also in the part other than the welded part. It will be in the state supported by. Therefore, the bonding strength of the metal lead 40 to the ceramic substrate 10 becomes stronger.

  Thus, according to the present embodiment, in addition to the effects described in the first embodiment, the effect of reinforcing the bonding strength of the metal lead 40 by the lead support portion 60 is exhibited. Therefore, it is preferable when configuring a circuit device having excellent bonding reliability of the metal lead 40. Moreover, this embodiment is applicable to each above-mentioned embodiment.

(Seventh embodiment)
FIG. 9 is a diagram showing a schematic cross-sectional configuration of a circuit device according to the seventh embodiment of the present invention. The circuit device according to this embodiment is different from the circuit device according to the first embodiment in that the “lead support portion 61” is added.

  Here, as shown in FIG. 9, the lead support portion 61 is a portion of the metal lead 40 other than the welded portion that is opposed to one surface of the ceramic substrate 10 so as to be in contact with the ceramic substrate 10. The bent portion 61 is configured.

  In this case, the bent portion 61 as the lead support portion becomes a contact portion of the metal lead 40 to the ceramic substrate 10, and the metal lead 40 is supported by the ceramic substrate 10 through the bent portion 61.

  Therefore, also in the present embodiment, as in the sixth embodiment, the metal lead 40 is supported by the ceramic substrate 10 at portions other than the welded portion, and the bonding strength of the metal lead 40 to the ceramic substrate 10 is stronger. It will be a thing.

(Eighth embodiment)
FIG. 10 is a diagram showing a schematic cross-sectional configuration of a circuit device according to the eighth embodiment of the present invention. The circuit device according to this embodiment is different from the circuit device according to the first embodiment in that the “lead support portion 62” is added.

  Here, as shown in FIG. 10, the lead support portion 62 is a metal member 62 made of Au or the like formed by a wire bonding method. The metal member 62 is connected to the pad 21 provided on one surface of the ceramic substrate 10 through the through hole 41 provided in the metal lead 40.

  That is, the metal member 62 exhibits a function like a rivet that presses the metal lead 40 through the so-called through-hole 41 and plays a role as a lead support portion. In this case, after the lead metal 40 and the conductor ball 30 are fixed by welding, the metal member 62 is formed by performing wire bonding on the pad 21 of the ceramic substrate 10 through the through hole 41 of the metal lead 40. The

  In this embodiment, since the metal lead 40 is fixed and supported by the pad 21 of the ceramic substrate 10 by the metal member 62, the same effect as in the sixth embodiment is expected.

  In addition, the lead support part should just support the metal lead 40 to the ceramic substrate 10 in parts other than a welding part, and was provided only in both or one of the metal lead 40 and the ceramic substrate 10. Alternatively, the members 10 and 40 may be separate members.

  In the sixth embodiment and the seventh embodiment, the lead support portions are provided on the metal leads 40, respectively. In the eighth embodiment, the metal leads 40 and the ceramic substrate 10 are separate from each other. For example, the lead support portion may be a protrusion provided integrally with the ceramic substrate 10 to support the metal lead 40.

(Ninth embodiment)
FIG. 11 is a diagram showing a schematic configuration of a circuit device according to a ninth embodiment of the present invention, in which (a) is a cross-sectional view and (b) is a top view in (a). The circuit device according to the present embodiment is different from the circuit device according to the first embodiment in that the “positioning unit 70” is added.

  As shown in FIG. 11, the positioning portion 70 of the present embodiment is a recess 70 provided in a portion of one surface of the ceramic substrate 10 that faces the metal lead 40. As shown in FIG. 11B, the recess 70 has a width that is slightly larger than the width of the metal lead 40, and both ends of the recess 70 protrude from the metal lead 40.

  Therefore, when the metal lead 40 is mounted on the ceramic substrate 10, the metal lead 40 can be easily positioned with respect to the ceramic substrate 10 by superimposing the metal lead 40 on the recess 70.

  As described above, according to the present embodiment, in addition to the effects described in the first embodiment, it is possible to exert the effect of facilitating the positioning of the metal lead 40 by the positioning portion 70. Moreover, this embodiment is applicable to each above-mentioned embodiment. In addition, when using this positioning part together with the said lead support part, what is necessary is just to provide a positioning part in the position which avoided the said lead support part.

(10th Embodiment)
FIG. 12 is a diagram showing a schematic plan configuration of a circuit device according to the tenth embodiment of the present invention. The circuit device according to the present embodiment is also different from the circuit device according to the first embodiment in that the “positioning unit 71” is added.

  As shown in FIG. 12, the positioning portion 71 of the present embodiment is configured by a protrusion 71a extending from the ceramic substrate 10 and a through hole 71b provided in the metal lead 40 and into which the protrusion 71a is inserted.

  In the case of this configuration, when the metal lead 40 is mounted on the ceramic substrate 10, the metal lead 40 can be easily positioned with respect to the ceramic substrate 10 by inserting the protrusion 71a into the through hole 71b. As described above, also in this embodiment, the same effect as that of the ninth embodiment is exhibited.

  In this embodiment, if the protrusion 71a on the ceramic substrate 10 side is press-fitted into the through hole 71b on the metal lead 40 side, the metal lead 40 is fixed and supported by the protrusion 71a. That is, in this case, it is possible to exert an effect that the bonding strength of the metal lead 40 is reinforced.

  Further, as described above, the positioning portions 70 and 71 are configured to be provided on both the ceramic substrate 10 and the metal lead 40 as the concave portion 70 provided on the ceramic substrate 10 side or the protrusion 71a and the through hole 71b. However, for example, a protrusion provided only on the metal lead 40 may be used as the positioning portion.

(Eleventh embodiment)
FIG. 13 is a diagram showing a schematic configuration of a circuit device according to an eleventh embodiment of the present invention, in which (a) is a cross-sectional view showing a first example, (b) is a cross-sectional view showing a second example, (C) is a top view which shows the 3rd example. The circuit device according to the present embodiment is different from the circuit device according to the first embodiment in that the “stress relaxation portion 80” is added.

  As shown in FIG. 13, the stress relaxation portion 80 is provided on the metal lead 40. The stress relieving portion 80 relieves the stress applied to the welded portion between the conductor ball 30 and the metal lead 40, and here, a part of the metal lead 40 is partially thinned.

  Thinning part of the metal lead 40 in this way may reduce the thickness of the metal lead 40 as shown in FIGS. 13A and 13B, or FIG. As shown in c), the width of the metal lead 40 may be narrowed. By doing in this way, this thinned stress relaxation part 80 becomes easy to deform | transform, and it becomes possible to relieve the stress added to the said weld part.

  In FIG. 13B, not only the stress relaxation portion 80 but also the welded portion is made as thin as the stress relaxation portion 80. In this case, the conductor ball 30 of the metal lead 40 is also thin. There is also an effect that welding to the metal becomes easy.

  Moreover, this embodiment is applicable to each above-mentioned embodiment, In that case, in addition to the effect of each above-mentioned embodiment, the improvement of the joining reliability of a welding part is anticipated. Further, the specific shape of the stress relaxation portion 80 is not limited to a configuration in which a part of the metal lead 40 as shown in FIG.

(Twelfth embodiment)
FIG. 14 is a view showing various shapes of the hole 11 according to the twelfth embodiment of the present invention, wherein (a) to (c) are cross-sectional shapes of the hole 11, and (d) to (f) are holes. The planar shape of the part 11, ie, an opening shape, is shown. This embodiment shows various shapes of the hole 11 applicable in each of the above embodiments.

  In each of the embodiments described above, the cross section of the hole 11 was rectangular, but as shown in FIG. 14, the cross section of the hole 11 has (a) a forward taper, (b) a reverse taper, (C) It may be stepped. Moreover, as shown in FIG. 14, the opening of the hole 11 may be (d) a triangle, (e) a quadrangle, (f) a circle, or the like. In short, the shape of the hole 11 is not particularly limited, and various shapes can be adopted.

(13th Embodiment)
FIG. 15 is a schematic sectional view showing a circuit device according to a thirteenth embodiment of the present invention. In each of the above embodiments, the welding configuration with the conductor ball 30 interposed is realized, but in this embodiment, a “method for manufacturing a circuit device without the conductor ball 30 interposed” is provided.

  The circuit device shown in FIG. 15 is the same as the circuit device 100 shown in the first embodiment (see FIGS. 1 to 3), except that the conductor ball 30 is omitted and the metal lead 40 and the metal circuit layer 20 are directly connected. Welding. Here, in the present embodiment, a part of the metal lead 40 melted by welding enters the hole 11. Here, the position of the hole 11 can be the same as that in the first embodiment.

  In the manufacturing method of the present embodiment, first, as the ceramic substrate 10, a ceramic substrate 10 having a hole 11 that opens on the one surface is prepared. Next, the metal lead 40 is disposed on the hole 11 and the metal circuit layer 20 on one surface of the ceramic substrate 10, and the metal lead 40 and the metal circuit layer 20 are brought into contact with each other.

  Subsequently, the metal lead 40 and the metal circuit layer 20 are joined by welding, and a part of the metal lead 40 melted by this welding is allowed to enter the hole portion 11. If this welding is performed by laser welding or electron beam welding, it is easy to melt part of the metal lead 40 and enter the hole 11.

  According to the present embodiment, when a part of the metal lead 40 enters the hole 11, the bonding strength between the metal lead 40 and the ceramic substrate 10 is ensured by the anchor effect. Therefore, it is possible to secure the bonding strength of the metal lead 40 to the ceramic substrate 10 and prevent the separation as much as possible without using the above-described conductor balls.

(Other embodiments)
In each of the first to twelfth embodiments, the metal lead 40 having a roughened surface may be employed. In this case, for example, the surface of the metal lead 40 can be constituted by roughened Ni plating, or can be realized by a general method of roughening etching a plated film such as Cu.

  In this case, the connection strength between the conductor ball 30 and the metal lead 40 is improved by the anchor effect obtained by roughening the metal lead 40. Further, when laser welding is performed, the laser is easily absorbed by the roughened surface of the metal lead 40, so that welding is facilitated.

  In each of the first to twelfth embodiments described above, the conductor ball 30 and the metal lead 40 are welded by laser welding or electron beam welding. However, these weldings may be performed by ultrasonic welding. In this case, the melting part 50 penetrating from the entire metal lead 40 to the conductor ball 30 as described above is not formed. Further, in all the above embodiments, the number of the melting portions 50 is not limited to one and may be plural.

1 is a schematic cross-sectional view of a circuit device according to a first embodiment of the present invention. It is a single-piece | unit structure figure of the ceramic substrate in FIG. FIG. 2 is a schematic plan view on one surface of a ceramic substrate in the circuit device in FIG. 1. It is process drawing which shows the manufacturing method of the circuit device of 1st Embodiment. It is process drawing which shows the manufacturing method of the circuit apparatus which concerns on 2nd Embodiment of this invention. It is a schematic sectional drawing of the circuit apparatus which concerns on 3rd Embodiment of this invention. It is a schematic sectional drawing of the circuit apparatus which concerns on 4th Embodiment of this invention. It is a schematic sectional drawing of the circuit apparatus which concerns on 6th Embodiment of this invention. It is a schematic sectional drawing of the circuit apparatus which concerns on 7th Embodiment of this invention. It is a schematic sectional drawing of the circuit apparatus which concerns on 8th Embodiment of this invention. It is a figure which shows schematic structure of the circuit apparatus which concerns on 9th Embodiment of this invention, (a) is sectional drawing, (b) is a top view in (a). It is a schematic plan view of the circuit device concerning a 10th embodiment of the present invention. It is a figure which shows schematic structure of the circuit apparatus based on 11th Embodiment of this invention, (a) is sectional drawing which shows a 1st example, (b) is sectional drawing which shows a 2nd example, (c) is It is a top view which shows a 3rd example. It is a figure which shows the various shapes of the hole which concerns on 12th Embodiment of this invention, (a)-(c) shows the cross-sectional shape of a hole, (d)-(f) shows the planar shape of a hole. . It is a schematic sectional drawing which shows the circuit apparatus based on 13th Embodiment of this invention.

Explanation of symbols

10 ... Ceramic substrate, 11 ... Hole, 13 ... Active metal layer,
20 ... Metal circuit layer, 30 ... Conductor ball as conductor, 40 ... Metal lead,
50 ... Melting part, 60-62 ... Lead support part, 70, 71 ... Positioning part,
80: Stress relaxation part.

Claims (14)

A ceramic substrate (10) made of ceramic, a metal circuit layer (20) formed on one surface of the ceramic substrate (10), and a metal lead (40) electrically connected to the metal circuit layer (20) In a circuit device having
One surface of the ceramic substrate (10) is provided with a hole (11) that opens to the one surface.
On the hole (11), there is provided a conductor (30) electrically connected to the metal circuit layer (20) in a state where a part thereof enters the hole (11).
The circuit device, wherein the metal lead (40) is disposed on the conductor (30), and the conductor (30) and the metal lead (40) are welded. The circuit device according to claim 1, wherein welding of the conductor (30) and the metal lead (40) is performed by laser welding or electron beam welding. In the welded portion between the conductor (30) and the metal lead (40),
The molten portion (50) formed by melting the metal lead (40) and the conductor (30) is located on the metal lead (40) from the surface opposite to the conductor (30). The circuit device according to claim 2, wherein the circuit device is continuously formed to the conductor (30). The circuit device according to any one of claims 1 to 3, wherein an inner surface of the hole (11) is roughened. An active metal layer (13) made of an active metal is provided on the inner surface of the hole (11), and the active metal layer (13) and a portion of the conductor (30) that enters the hole (11). The circuit device according to claim 1, wherein the circuit device is in close contact with each other. 6. The circuit device according to claim 1, wherein the conductor (30) contains Ti. The circuit device according to any one of claims 1 to 6, wherein a plurality of the hole portions (11) are provided. Lead support portions (60 to 62) for supporting the metal lead (40) on the ceramic substrate (10) are provided at portions other than the welded portion between the conductor (30) and the metal lead (40). The circuit device according to claim 1, wherein the circuit device is provided. Positioning portions (70, 71) for positioning the metal lead (40) with respect to the ceramic substrate (10) are provided on at least one of the ceramic substrate (10) and the metal lead (40). The circuit device according to claim 1, wherein: The metal lead (40) is provided with a stress relaxation portion (80) for relaxing stress applied to a welded portion between the conductor (30) and the metal lead (40). The circuit device according to any one of Items 9 to 9. A first step of forming a metal circuit layer (20) on one surface of a ceramic substrate (10) made of ceramic and providing a hole (11) opening on the one surface of the ceramic substrate (10);
Next, the conductor (30) is disposed on the hole (11) on one surface of the ceramic substrate (10), and a part of the conductor (30) is allowed to enter the hole (11). And a second step of electrically connecting the conductor (30) and the metal circuit layer (20) and welding the conductor (30) and the metal lead (40). A method,
In the second step, after the placement of the conductor (30) on the hole (11) and the electrical connection between the conductor (30) and the metal circuit layer (20), A method of manufacturing a circuit device, wherein the metal lead (40) is mounted on the conductor (30), and the conductor (30) and the metal lead (40) are welded. A first step of forming a metal circuit layer (20) on one surface of a ceramic substrate (10) made of ceramic and providing a hole (11) opening on the one surface of the ceramic substrate (10);
Next, the conductor (30) is disposed on the hole (11) on one surface of the ceramic substrate (10), and a part of the conductor (30) is allowed to enter the hole (11). And a second step of electrically connecting the conductor (30) and the metal circuit layer (20) and welding the conductor (30) and the metal lead (40). A method,
In the second step, after the conductor (30) is attached to the metal lead (40), the conductor (30) is disposed on the hole (11), the conductor (30) and the metal A method of manufacturing a circuit device, wherein electrical connection with a circuit layer (20) and welding of the conductor (30) and the metal lead (40) are performed. A ceramic substrate (10) made of ceramic, a metal circuit layer (20) formed on one surface of the ceramic substrate (10), and a metal lead (40) electrically connected to the metal circuit layer (20) In a method of manufacturing a circuit device having:
As the ceramic substrate (10), one having a hole (11) opening in the one surface is prepared,
The metal lead (40) is disposed on the hole (11) on one surface of the ceramic substrate (10), and the metal lead (40) and the metal circuit layer (20) are brought into contact with each other.
Subsequently, the metal lead (40) and the metal circuit layer (20) are joined by welding, and a part of the metal lead (40) melted by the welding is allowed to enter the hole (11). A method for manufacturing a circuit device. 14. The circuit device manufacturing method according to claim 13, wherein welding of the conductor (30) and the metal lead (40) is performed by laser welding or electron beam welding.

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