Patent Description:
There is known a wiring board for mounting thereon an electronic component e.g. semiconductor element, which includes: an insulating substrate made of a non-conductive material such as a ceramic material, resin material or glass material; and a plurality of external connection terminals (also called "connection pads") made of a conductive material such as a metal material on the insulating substrate.

<CIT> discloses one such type of wiring board, including: an insulating substrate; a plurality of pad conductors disposed on a first main surface of the insulating substrate; a coating layer of non-conductive material covering from the first main surface of the insulating substrate to outer peripheral portions of the pad conductors. In this wiring board, center portions of the pad conductors exposed from the coating layer serve as connection pads, respectively. In other words, the coating layer defines the connection pads by covering the outer peripheral portions of the pad conductors. For example, the coating layer can be made of a ceramic, organic resin or glass material of the same kind as or a different kind from the insulating substrate. <CIT> discloses a printed circuit board and semiconductor package using the same.

In the above-disclosed wiring board, the coating layer of non-conductive material is applied to the outer peripheral portions of the pad conductors. In this way, there are cases where the coating layer is formed to overlap and cover parts of the connection pads for the purpose of preventing damage to surfaces of the connection pads and entry of foreign matter between the connection pads. Such a layer structure is called an "overcoat structure". It is conceivable to form the overcoat structure by arranging the connection pads in a predetermined pattern on the insulating layer, and then, laminating the coating layer of non-conductive material (such as alumina) to cover from the insulating substrate to outer peripheral portions of the connection pads, whereby portions of the connection pads exposed from the coating layer serve as connection terminals for connection to other connection members such as solder balls.

In the overcoat structure, the actual diameter of the connection pads located under the coating layer is larger than the diameter of the exposed portions of the connection pads serving as the connection terminals. When it is demanded to narrow the intervals between the adjacent connection pads for high definition and miniaturization of the wiring board, the connection pads have to be located very close to each other under the coating layer.

However, the narrowing of the intervals between the adjacent connection pads raises difficulties in manufacturing process. The narrowing of the intervals between the adjacent connection pads also raises a high possibility of short circuit between the adjacent connection pads, which results in an increase of defective product rate.

In view of the foregoing, it is a main advantage of the present invention to provide a wiring board capable of protecting surfaces of connection terminals without narrowing the intervals between the adjacent connection terminals and to provide a method for manufacturing such a wiring board.

According to one aspect of the present invention, there is provided a wiring board according to claim <NUM>, comprising: an insulating substrate; a plurality of connection terminals arranged on the insulating substrate; and a plurality of non-conductive protruding parts respectively arranged on areas of the insulating substrate except areas on which the plurality of connection terminals are arranged, the non-conductive protruding parts having a height greater than that of the connection terminals.

According to the present invention, there is provided a manufacturing method of a wiring board as defined in claim <NUM>, comprising: providing an insulating substrate in which a plurality of columnar parts are arranged, the columnar parts being made of a material having a lower thermal shrinkage rate than that of the insulating substrate; arranging connection terminals on areas of the insulating substrate except areas corresponding in position to the columnar parts; depositing a non-conductive material over the columnar parts on the insulating substrate; and heating or firing the insulating substrate on which the non-conductive material has been deposited, so as to allow the columnar parts to partially protrude from the insulating substrate due to a difference in thermal shrinkage rate between the insulating substrate and the columnar parts and thereby form protruding parts containing the non-conductive material.

The other objects and features of the present invention will also become understood from the following description.

Hereinafter, exemplary embodiments of the present invention will be described in detail below with reference to the drawings. In the following description, like parts and portions are designated by like reference numerals. These like parts and portions have the same names and functions. Thus, repeated explanation of the like parts and portions will be omitted herefrom. Further, the terms "upper", "lower", "under", "below", "above" etc. are used to describe relative locations of parts and portions as shown in the drawings.

The first embodiment, which is not part of the claimed invention, specifically refers to a wiring board <NUM> usable for various electronic devices.

<FIG> shows a configuration of the wiring board <NUM>. The wiring board <NUM> is shown in plan in the upper part of <FIG>. In the lower part of <FIG>, the wiring board <NUM> is shown in cross section along line A-A.

As shown in <FIG>, the wiring board <NUM> generally includes an insulating substrate <NUM>, a plurality of connection pads <NUM> (as connection terminals) and a plurality of protruding parts <NUM> (as non-conductive protruding parts).

The insulating substrate <NUM> is made of an insulating material. In the first embodiment, the insulating substrate <NUM> contains a ceramic material as a predominant component. The term "predominant component" as used herein means a component whose content (in terms of wt%) is the highest among all components of the insulating substrate <NUM>. Examples of the insulating material are a ceramic material containing alumina (Al<NUM>O<NUM>), a glass-ceramics composite material such as LTCC (low temperature co-fired ceramics) and the like. The insulating substrate <NUM> may have a laminated structure formed by laminating a plurality of insulating material layers (such as ceramic green sheets).

The plurality of connection pads <NUM> are arranged on an upper main surface of the insulating substrate <NUM>. In the first embodiment, the connection pads <NUM> are aligned at substantially equal intervals in lengthwise and widthwise directions of the insulating substrate <NUM>, that is, arranged two-dimensionally in a grid pattern. Thus, the conductive pads <NUM> are also called "BGA (ball grid array) pads", "LGA (land grid array) pads", "PGA (pin grid array) pads" etc..

Each of the conductive pads <NUM> is made of a conductive material. Examples of the conductive material are metal materials such as copper (Cu), silver (Ag), palladium (Pd), gold (Au), platinum (Pt), tungsten (W), molybdenum (Mo), nickel (Ni), manganese (Mn) and alloys thereof. These metal materials can be applied to the insulating substrate <NUM> by metallization, plating, deposition etc. The conductive pads <NUM> may contain an inorganic material such as glass or alumina in addition to the metal material.

In the case where the connection pads <NUM> are provided as metallization layers of tungsten (W), molybdenum (Mo) etc., it is feasible to form the connection pads <NUM> by e.g. kneading a powder of the aforementioned metal with an organic solvent and a binder, applying the resulting metal paste in a predetermined pattern onto a ceramic green sheet as the material of the insulating substrate <NUM> and then co-firing the ceramic green sheet and the applied metal paste. The application of the metal paste can be done by a conventionally known printing technique such as screen printing.

The plurality of protruding parts <NUM> are arranged on areas of the upper main surface of the insulating substrate <NUM> except areas on which the conductive pads <NUM> are arranged. In the first embodiment, the plurality of protruding parts <NUM> are arranged in such a manner that each of the protruding parts <NUM> is located between diagonally adjacent ones of the two-dimensionally arranged connection pads <NUM> as shown in the plan view of <FIG>.

Each of the protruding parts <NUM> is made of a non-conductive material. In the first embodiment, the protruding parts <NUM> are each made of a ceramic material containing alumina (Al<NUM>O<NUM>). The protruding parts <NUM> are thus hereinafter also referred to as "alumina protruding parts <NUM>". In the present invention, however, the material of the protruding parts <NUM> is not limited to the ceramic material. The protruding parts <NUM> may alternatively be made of any other non-conductive material such as resin material e.g. solder resist, glass-ceramics composite material e.g. LTCC, glass material, or the like.

As shown in the cross-sectional view of <FIG>, the height of the alumina protruding parts <NUM> is greater than the height of the connection pads <NUM>. Herein, the height of the alumina protruding part <NUM> means a distance from the upper surface of the insulating substrate <NUM> to an uppermost point of the alumina protruding part <NUM>; and the height of the connection pad <NUM> means a distance from the upper surface of the insulating substrate <NUM> to an uppermost point of the connection pad <NUM>. Accordingly, the distance from the upper surface of the insulating substrate <NUM> to the uppermost points of the alumina protruding parts <NUM> is greater than the distance from the upper surface of the insulating substrate <NUM> to the uppermost points of the connection pads <NUM>. In the first embodiment shown in <FIG>, the height of the alumina protruding parts <NUM> is greater by a distance h1 than the height of the connection pads <NUM>.

In such a configuration, the alumina protruding parts <NUM> of greater height are arranged in the vicinities of the connection pads <NUM>. The connection pads <NUM> are thus made unlikely to come into contact with other parts or members so that surfaces of the connection pads <NUM> can be protected by the alumina protruding parts <NUM>.

Further, each of the alumina protruding parts <NUM> is formed in a vertically elongated column shape and is located between adjacent ones of the connection pads <NUM> at a distance away from the connection pads <NUM> so as not to interfere with the connection pads <NUM> in the first embodiment. This ensures the areas of arrangement of the alumina protruding parts <NUM> at locations outside of (different from) the areas of arrangement of the connection pads <NUM> while maintaining the intervals between the connection pads <NUM>.

The correlation between the arrangement areas of the alumina protruding parts <NUM> and the intervals between the correction pads <NUM> will be explained in more detail below with reference to <FIG>, <FIG> and <FIG>.

<FIG> shows a wiring board <NUM> according to a modified example of the first embodiment. The wiring board <NUM> is shown in plan in the upper part of <FIG>. In the lower part of <FIG>, the wiring board <NUM> is shown in cross section along line B-B.

<FIG> shows a configuration of the conventional wiring board <NUM>. The wiring board <NUM> is shown in plan in the upper part of <FIG>. In the lower part of <FIG>, the wiring board <NUM> is shown in cross section along line D-D.

As shown in <FIG>, the conventional wiring board <NUM> has connection pads <NUM> arranged on the insulating substrate <NUM>, with a coating layer <NUM> of non-conductive material covering from the insulating substrate <NUM> to outer peripheral portions of the connection pads <NUM>. The coating layer <NUM> is formed to overlap and cover parts of the connection pads <NUM> (see the cross-sectional view of <FIG>) for the purpose of preventing damage to surfaces of the connection pads <NUM> and entry of foreign matter between the connection pads <NUM>. The coating layer <NUM> is thus also called "overcoat layer". In the conventional example shown in <FIG>, the overlap between the coating layer <NUM> and the outer peripheral portion of the connection pad <NUM> is provided with a width d3 (e.g. greater than or equal to <NUM> and smaller than or equal to <NUM>).

The coating layer <NUM> is formed by e.g. arranging the connection pads <NUM> in a predetermined pattern on the insulating substrate <NUM>, and then, laminating the non-conductive material (such as alumina) on the insulating substrate to cover the outer peripheral portions of the connection pads <NUM>. Then, portions of the connection pads <NUM> exposed from the coating layer <NUM> respectively serve as connection terminals for connection to other connection members such as solder balls.

In the conventional wiring board <NUM>, the actual diameter d1 (e.g. <NUM>) of the connection pads <NUM> located under the coating layer <NUM> is larger than the diameter d2 (e.g. <NUM>) of the exposed portions of the connection pads <NUM> serving as the connection terminals. When it is demanded to narrow the apparent intervals d4 (e.g. <NUM>) between the adjacent connection pads <NUM> for high definition and miniaturization of the wiring board <NUM>, the connection pads <NUM> have to be located very close to each other under the coating layer <NUM>. In the conventional example shown in <FIG>, the actual intervals between the adjacent connection pads <NUM> under the coating layer <NUM> are narrowed to a very small value d5 (e.g. <NUM>).

However, the narrowing of the actual intervals d5 between the adjacent connection pads <NUM> raises difficulties in manufacturing process. The narrowing of the actual intervals d5 between the adjacent connection pads <NUM> also raises a high possibility of short circuit between the adjacent connection pads <NUM>, which results in an increase of defective product rate. Herein, the interval between the adjacent connection pads means a distance from an edge of one of two adjacent connection pads to an edge of the other of the two adjacent connection pads.

As in the wiring board <NUM> shown in <FIG>, it is hence desirable to arrange a protection layer <NUM> of alumina etc. and connection pads <NUM> on the insulating substrate <NUM> with no clearance created therebetween. In the modified example shown in <FIG>, the height of the alumina protection layer <NUM> is greater by a distance h1 than the height of the connection pads <NUM> as in the first embodiment shown in <FIG>. Thus, the alumina protection layer <NUM> serve as non-conductive protruding parts to protect surfaces of the connection pads <NUM> in the wiring board <NUM>.

In the case where, in the wiring board <NUM>, the diameter D1 of the connection pads <NUM> is <NUM>; and the center-to-center distance D2 of the adjacent connection pads <NUM> is <NUM>, the actual interval D3 between the adjacent connection pads <NUM> is <NUM>. In this way, a certain amount of interval is ensured between the adjacent connection pads <NUM> so that the possibility of short circuit between the adjacent connection pads <NUM> is reduced in the modification example.

In the modified example shown in <FIG>, however, it is required to perform patterning with very high positional accuracy for the formation of the connection pads <NUM> and the alumina protection layer <NUM>. Such very high accuracy patterning is difficult to perform by a conventionally known printing technique.

In the first embodiment, on the other hand, each of the alumina protruding parts <NUM> is located between adjacent ones of the connection pads <NUM> at a distance slightly away from these adjacent connection pads <NUM> as mentioned above. In the case where the diameter D1 and center-to-center distance D2 of the connection pads <NUM> of the wiring board <NUM> are set to the same as those of the wiring board <NUM>, the alumina protruding parts <NUM> can be located at some space away from the adjacent connection pads <NUM>. Furthermore, the alumina protruding parts <NUM> can be formed with relatively easily realizable dimensions (e.g. diameter D4 = <NUM>).

<FIG> shows a wiring board 1a according to another modified example of the first embodiment.

In the first embodiment, the alumina protruding parts <NUM> are arranged on all of areas between diagonally adjacent ones of the connection pads <NUM> as shown in <FIG>. The present invention is however not limited to such a configuration.

It suffices that the alumina protruding parts <NUM> are provided at least at three locations in a non-linear arrangement as in the wiring board 1a shown in <FIG>. In this configuration, when a plurality of the wiring board 1a are stacked together, a lower surface of the upper-side wiring board 1a is supported by upper ends of the alumina protruding parts <NUM> of the lower-side wiring board 1a so as to prevent the upper-side wiring board 1a from coming into contact with the connection pads <NUM> of the lower-side wiring board 1a, and thereby avoid damage to the connection pads <NUM> of the lower-side wiring board 1a. When the wiring board 1a is placed on e.g. a stage of component mounting equipment, the wiring board 1a is supported on the stage by contact of the alumina protruding parts <NUM> with a surface of the stage so as to avoid damage to the connection pads <NUM> of the wiring board 1a.

As mentioned above, the wiring board <NUM> according to the first embodiment is characterized in that the alumina protruding parts <NUM> are arranged on the areas of the insulating substrate <NUM> except the areas on which the connection pads <NUM> are arranged and each has a height greater than that the connection pads <NUM>. As the alumina protruding parts <NUM> of greater height than the connection pads <NUM> are arranged, the connection pads <NUM> are made unlikely to come into contact with other parts or members so that the surfaces of the connection pads <NUM> can be protected by the alumina protruding parts <NUM>. Further, the arrangement areas of the connection pads <NUM> would not be narrowed by the arrangement of the alumina protruding parts <NUM> as the alumina protruding parts <NUM> are arranged at locations outside of the arrangement areas of the connection pads <NUM>. The wiring board <NUM> therefore provides effective protection for the surfaces of the connection pads <NUM> without narrowing the intervals between the adjacent connection pads <NUM>.

In particular, each of the alumina protruding parts <NUM> is arranged between adjacent ones of the connection pads <NUM> in the first embodiment. In such an arrangement, the alumina protruding parts <NUM> are located in the vicinities of the connection pads <NUM> so that the connection pads <NUM> can be more adequately protected by the alumina protruding parts <NUM>. Moreover, the arrangement of the alumina protruding parts <NUM> between diagonally adjacent ones of the connection pads <NUM> makes it easy to ensure the arrangement areas (occupancy areas) of the alumina protruding parts <NUM> and thereby makes it possible to increase the diameter of the alumina protruding parts <NUM>.

Although the alumina protruding parts <NUM> are circular-column shaped in the first embodiment as shown in <FIG>, the shape of the alumina protruding parts <NUM> is not limited to the circular column shape. The alumina protruding parts <NUM> may have any other shape such as tapered column shape that gradually decreases in diameter toward the upper side (e.g. conical frustum shape, pyramidal frustum shape etc.).

The second embodiment, which is an embodiment of the invention, specifically refers to a wiring board <NUM>.

<FIG> shows a configuration of the wiring board <NUM>. The wiring board <NUM> is shown in plan in the upper part of <FIG>. In the lower part of <FIG>, the wiring board <NUM> is shown in cross section along line C-C.

As shown in <FIG>, the wiring board <NUM> generally includes an insulating substrate <NUM>, a plurality of connection pads <NUM> (as connection terminals), a plurality of protruding parts <NUM> (as non-conductive protruding parts) and a plurality of columnar parts <NUM>. The insulating substrate <NUM> and connection pads <NUM> of the wiring board <NUM> according to the second embodiment are the same in configuration as those of the wiring board <NUM> according to the first embodiment.

The plurality of protruding parts <NUM> are arranged on areas of the upper main surface of the insulating substrate <NUM> except areas on which the conductive pads <NUM> are arranged. In the second embodiment, the plurality of protruding parts <NUM> are arranged in such a manner that each of the protruding parts <NUM> is located between diagonally adjacent ones of the two-dimensionally arranged connection pads <NUM> as shown in the plan view of <FIG>.

Each of the protruding parts <NUM> is made of a non-conductive material. In the second embodiment, the alumina protruding parts <NUM> are each made of a ceramic material containing alumina (Al<NUM>O<NUM>) as in the first embodiment. The protruding parts <NUM> are thus hereinafter also referred to as "alumina protruding parts <NUM>". In the present invention, however, the material of the protruding parts <NUM> is not limited to the ceramic material. Regarding the material of the protruding parts <NUM>, there can be used the same materials as those mentioned above as the material of the protruding parts <NUM> in the first embodiment.

As shown in the cross-sectional view of <FIG>, the height of the alumina protruding parts <NUM> is greater than the height of the connection pads <NUM>. Herein, the height of the alumina protruding part <NUM> means a distance from the upper surface of the insulating substrate <NUM> to an uppermost point of the alumina protruding part <NUM>; and the height of the connection pad <NUM> means a distance from the upper surface of the insulating substrate <NUM> to an uppermost point of the connection pad <NUM>. In the second embodiment shown in <FIG>, the height of the alumina protruding parts <NUM> is greater by a distance h2 than the height of the connection pads <NUM>.

The plurality of columnar parts <NUM> are arranged below the alumina protruding parts <NUM>, respectively. More specifically, the columnar parts <NUM> are embedded in the insulating substrate <NUM> at positions corresponding to the alumina protruding parts <NUM>, with upper end portions of the columnar parts <NUM> protruding from the upper surface of the insulating substrate <NUM> and being covered by the alumina protruding parts <NUM>, as shown in the cross-sectional view of <FIG>.

Each of the columnar parts <NUM> is made of a material having a lower thermal shrinkage rate than that of the insulating substrate <NUM>. In the second embodiment, the insulating substrate <NUM> contains a ceramic material as a predominant component as in the first embodiment; whereas the columnar parts <NUM> contain as a predominant component a metal material lower in thermal shrinkage rate than the ceramic material. The term "predominant component" as used herein means a component whose content (in terms of wt%) is the highest among all components of the insulating substrate <NUM> or the columnar part <NUM>. Examples of the metal material are copper (Cu), silver (Ag), palladium (Pd), gold (Au), platinum (Pt), tungsten (W), molybdenum (Mo) and manganese (Mn). The columnar parts <NUM> may be made of the same material as the connection pads <NUM>.

As will be explained in detail below, the columnar parts <NUM> are caused to partially protrude from the surface of the insulating substrate <NUM> under the application of heat by firing during the manufacturing process of the wiring board <NUM> due to a difference in thermal shrinkage rate between the insulating substrate <NUM> and the columnar parts <NUM>. With the protrusion of the columnar parts <NUM>, the alumina protruding parts <NUM> located above the columnar parts <NUM> protrude to a greater height. As a result, a sufficient height of the alumina protruding parts <NUM> is ensured.

<FIG> show the respective steps of the manufacturing process of the wiring board <NUM>.

First, the columnar parts <NUM> are arranged in the insulating substrate <NUM> at predetermined positions as shown in <FIG>. The predetermined positions correspond to the areas of the insulating substrate <NUM> on which the connection pads <NUM> are to be arranged in the subsequent step. At this time, the diameter D5 of the columnar parts <NUM> is set smaller than the diameter D6 of the alumina protruding parts <NUM> formed in the later step. Further, the upper surfaces of the columnar parts <NUM> are in flush with the upper surface of the insulating substrate <NUM> in the second embodiment.

Next, the connection pads <NUM> are formed and arranged on the predetermined areas of the insulating substrate <NUM>. As mentioned above, the connection pads <NUM> can be formed by a conventionally known printing technique such as screen printing.

Subsequently, a non-conductive material 213a as the raw material of the alumina protruding parts <NUM> is deposited on the areas of the insulating substrate <NUM>, except the areas on which the connection pads <NUM> are arranged, so as to overlap and cover the columnar parts <NUM> as shown in <FIG>. In the second embodiment, the ceramic material containing alumina (Al<NUM>O<NUM>) is used as the non-conductive material 213a as mentioned above. The non-conductive material 213a can be deposited by a conventionally known printing technique such as screen printing.

After that, the insulating substrate <NUM> in which the columnar parts <NUM> have been arranged and on which the non-conductive material 213a has been deposited is subjected to firing. The insulating substrate <NUM>, the columnar parts <NUM> and the non-conductive material 213a undergo shrinkage under the application of heat by firing. Since the thermal shrinkage rate of the columnar part <NUM> is lower than the thermal shrinkage rate of the insulating substrate <NUM>, the amount of shrinkage of the insulating substrate <NUM> is larger than the amount of shrinkage of the columnar part <NUM>. Consequently, there occurs a change in configuration such that the columnar parts <NUM> partially protrude from the thermally shrunk insulating substrate <NUM> as shown by arrows in <FIG>. With such a configuration change, the non-conductive material 213a is pushed upward and thereby formed into protrusions. There are thus provided the alumina protruding parts <NUM>. The thus-provided alumina protruding parts <NUM> have a circular column shape or a substantially conical frustum shape that decreases in diameter toward the upper side.

In the manufacturing process of the wiring board <NUM>, the alumina protruding parts <NUM> are formed to protrude to a greater height than the connection pads <NUM> with the aid of a difference in thermal shrinkage rate between the material (e.g. ceramic material) of the insulating substrate <NUM> and the material (e.g. metal material) of the columnar parts <NUM> as mentioned above. The difference h2 between the height of the alumina protruding parts <NUM> and the connection pads <NUM> in the second embodiment is hence set larger than the difference h1 between the height of the alumina protruding parts <NUM> and the connection pads <NUM> in the first embodiment. As the difference h2 between the height of the alumina protruding parts <NUM> and the connection pads <NUM> in the second embodiment is set larger, it is more unlikely that the connection pads <NUM> will come into contact with other parts or members even under the influence of warpage or deformation of the wiring board <NUM> itself.

Each of the columnar parts <NUM> arranged in the insulating substrate <NUM> may be in multilayer form. In this case, the height of protrusion of the columnar part <NUM> from the surface of the insulating substrate <NUM> after the application of heat is made larger by setting the diameter D5 of the lower layer of the multilayer columnar part <NUM> larger. The height of protrusion of the columnar part <NUM> from the surface of the insulating substrate <NUM> after the application of heat is also made larger by using a metal material with a lower thermal shrinkage rate (e.g. a metal material lower in thermal shrinkage rate than the metal material of the connection pads <NUM>) as the material of the columnar part <NUM>.

In a modified example of the second embodiment, not only the columnar parts <NUM> but also additional (second) columnar parts may be provided inside the insulating substrate <NUM>. For example, the second columnar parts serve as vias for connection of connection terminals to wirings inside the insulating substrate <NUM>. Each of the second columnar parts is made of a conductive material such as metal material. In the case where the second columnar parts are provided, it is preferable to select and use as the material of the columnar parts <NUM> a material having a lower thermal shrinkage rate than that of the second columnar parts. By the selection and use of such materials, the height of protrusion of the columnar parts <NUM> from the surface of the insulating substrate <NUM> after the firing is made larger than that of the second columnar parts.

The third embodiment, which is not part of the claimed invention, specifically refers to a wiring board <NUM>. The wiring board <NUM> according to the third embodiment is structurally the same as the wiring boards <NUM> and <NUM> according to the first and second embodiments, except for the configuration of non-conductive protruding parts.

<FIG> and <FIG> show configuration examples of the non-conductive protruding parts.

In the example shown in <FIG>, the non-conductive protruding parts provided are alumina protruding parts 313a having a square shape when viewed in plan. For instance, the diameter ϕ of the connection pads <NUM> is set to e.g. <NUM>; and the length L of one side of the square-shaped alumina protruding parts 313a is set to e.g. <NUM>.

In the example shown in <FIG>, the non-conductive protruding parts provided are alumina protruding parts 313b having an acute-angled square shape in plan view. In this case, the areas of arrangement of the alumina protruding parts 313b is ensured easily and reliably even when the intervals between the connection pads <NUM> is made narrower.

It is alternatively feasible to provide, as the non-conductive protruding parts, oval-shaped alumina protruding parts 313c as shown in <FIG>, triangular-shaped alumina protruding parts 313d as shown in <FIG>, or cross-shaped alumina protruding parts 313e as shown in <FIG>. As shown in <FIG>, it is feasible to provide square-shaped alumina protruding parts 313f in a different orientation from that of the square-shaped alumina protruding parts 313a shown in <FIG>. The alumina protruding parts 313a, 313f may alternatively be rectangular in shape.

Claim 1:
A wiring board (<NUM>), comprising:
an insulating substrate (<NUM>);
a plurality of connection terminals (<NUM>) arranged on the insulating substrate (<NUM>); and
a plurality of non-conductive protruding parts (<NUM>) respectively arranged on areas of the insulating substrate (<NUM>) except areas on which the plurality of connection terminals (<NUM>) are arranged,
characterized in that the non-conductive protruding parts (<NUM>) have a circular column shape or a substantially conical frustum shape that decreases in diameter toward an upper side and have a height greater than that of the connection terminals (<NUM>); and
the wiring board further comprises columnar parts (<NUM>) respectively arranged under the non-conductive protruding parts (<NUM>) with portions of the columnar parts (<NUM>) embedded in the insulating substrate (<NUM>), and made of a material having a lower thermal shrinkage rate than that of the insulating substrate (<NUM>).