JPH05190699A - Wiring board and high-speed ic package - Google Patents

Abstract

PURPOSE:To change the width of the striplike conductor films of a microstrip line easily and to increase the degree of freedom of wiring design greatly. CONSTITUTION:The title wiring board is a kind of wiring board having a microstrip line composed of a dielectric board, and a grounding conductor film and striplike conductor films 7 and 8 provided on one surface and the other of the dielectric board respectively, and the dielectric board 61 is composed of at least two layers of dielectric sheets 1 and 6. Besides, a conductor layer 3 is provided at one part of the boundary area between the dielectric sheets, and the conductor layer 3 and grounding conductor film 2 are connected to each other electrically by a via 4 so as to be at approximately equal potential.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a wiring board and a high-speed IC package to which this structure is applied so that a desired characteristic impedance can be ensured even if the wiring width of a microstrip line or a strip line is changed.

[0002]

2. Description of the Related Art Generally, a wiring board has a dielectric substrate 101, a grounding conductor film 102 provided on one surface of the dielectric substrate 101, and the grounding conductor film, as shown in FIG. It is often configured by a microstrip line formed of a strip-shaped conductor film 103 provided on the surface facing the 102. In this configuration, the characteristic impedance of the microstrip line is the dielectric substrate 101.
If the relative permittivity ε _r is clear, the dielectric substrate 101
Is substantially determined by the thickness h and the width w of the strip-shaped conductor film 103. That is, the dielectric substrate 101
When the thickness h of the strip-shaped conductor film 103 is determined, the width w of the strip-shaped conductor film 103 corresponding to the predetermined characteristic impedance automatically becomes the predetermined width.

Another wiring board may be composed of strip lines as shown in FIG. this is,
The second dielectric substrate 106 is provided on the first dielectric substrate 104 having the grounding conductor film 105 on one surface,
On the upper surface of the second dielectric substrate 106, the ground conductive film 1 is formed.
07 are formed. Further, the first dielectric substrate 1
A strip-shaped conductor film 108 is provided between layers 04 and the second dielectric substrate 106. In the wiring board having such a structure, if the relative permittivity ε _{r of the} first dielectric substrate 104 and the second dielectric substrate 106 is clear, the characteristic impedance of the strip line is the first dielectric substrate. It is substantially determined by the thickness B of the substrate 104, the thickness B of the second dielectric substrate 106, and the width W of the strip-shaped conductor film 108. That is, when the thickness B of the dielectric material sandwiched between the grounding conductor films 105 and 107 is determined, the width W of the strip-shaped conductor film 108 corresponding to a predetermined characteristic impedance is automatically predetermined. Becomes the width of.

Furthermore, high-speed I using these wiring boards
Conventionally, the C package 200 generally has the configuration shown in FIG. That is, a conductive substrate, a first dielectric substrate 110 provided with an opening 109 for mounting a semiconductor element on the conductive substrate, and the first dielectric substrate 11
Second dielectric substrate 1 on the circumference of which is provided with an opening larger than the opening 109 and a partial cutout 118
11, a strip-shaped conductor film 112 and a similar strip-shaped conductor film 113 formed on the extension of the strip-shaped conductor film 112 are provided on the upper surface of the first dielectric substrate 110.
Metallic leads are provided on the conductor film 113. Further, in detail, FIG. 11 shows an enlarged plan view and an enlarged sectional view of the G portion in FIG. In the structure shown in these figures, the grounding conductor film 116 provided on the side of the conductive substrate 117 of the first dielectric substrate 110 and the surface facing the grounding conductor film 116 are provided. The strip-shaped conductor film 112 constitutes a microstrip line, and the conductor film 116 for grounding and the conductor film 115 provided on the upper surface of the second dielectric substrate 111 and the first dielectric substrate. 110 and the second dielectric substrate 11
A strip line is formed by the strip-shaped conductor films 114 provided between the first layers, and the conductor film 11 is an extension of the strip-shaped conductor films 112 and 114.
3 and the first dielectric substrate 110 and the grounding conductor film 1
16 forms a microstrip line.
Further, a metallic lead 114a is formed on the conductor film 113.
Is provided. In such a high-speed IC package, the semiconductor element is mounted on the conductive substrate 117 in the opening 109, and the terminal of the semiconductor element and the end of the conductor film 113 are electrically connected by wire bonding or the like. When a high-speed signal is input to an input terminal composed of a metallic lead 114a and a conductor film 113, it is transmitted to the semiconductor element via other conductor films 111 and 112 and wire bonding. Thereafter, the output signal processed in the semiconductor device is taken out from another output terminal by the procedure reverse to the above.

[0005]

However, in the wiring board composed of the conventional microstrip line,
If the relative permittivity ε _r is clear, it is almost determined by the thickness of the dielectric substrate and the width of the strip-shaped conductor film.
That is, when the thickness of the dielectric substrate is determined, the width of the strip-shaped conductor film corresponding to the predetermined characteristic impedance is automatically set to the predetermined width, so that the width of the strip-shaped conductor film can be freely set. There was a drawback that could not be set. Further, in the conventional wiring board including the strip line, when the thickness of the dielectric substrate sandwiched between the two conductor films for grounding is determined, the dielectric substrate is matched with a predetermined characteristic impedance. Since the width of the strip-shaped conductor film provided between the layers is automatically set to a predetermined width, there is a drawback that the width of the strip-shaped conductor film is limited as described above. In addition, the first composed of a microstrip line
In the conventional high-speed IC package having, as the main wiring, the dielectric substrate, the strip line formed between the second dielectric substrate on which the conductor film on one surface is formed, and the first dielectric substrate, Similar to the above wiring board, the thickness of the first dielectric substrate and the thickness of the second dielectric substrate determine the width of the strip-shaped conductor film corresponding to the predetermined characteristic impedance of each line, There is a drawback in that the wiring cannot be routed by freely changing the width of the conductor film. On the other hand, the width of the strip-shaped conductor film is small in order to obtain a large number of wires in the developed part of the wires, and at the parts that will be the terminals of the package, the mechanical strength in joining the metallic leads, etc. Often takes a large amount. Therefore, if the characteristic impedance of the microstrip line in the expanded portion of the wiring is set to a predetermined value, the characteristic impedance of the portion that will be the terminal of the package cannot be made the same value, and the deterioration of the electrical characteristics at this portion will occur. There was a drawback. The present invention has the problems that the above-mentioned prior art has a problem that the line width of the line of the wiring board or the line width of the line used for the high-speed IC package is limited, and the electrical characteristics at the terminals of the high-speed IC package are deteriorated. New wiring board or high-speed I
The purpose is to provide a C package.

[0006]

In order to solve the above problems, the present invention provides a dielectric substrate, a grounding conductor film and a strip respectively provided on one surface and the other surface of the dielectric substrate. In a wiring board having a microstrip line made of a striped conductor film, the dielectric substrate is composed of at least two layers of dielectric sheets. Further, a conductor layer is provided in a part between layers of the dielectric sheet, and the conductor layer and the grounding conductor film are electrically connected to each other so that they have substantially the same potential. As a result, the wiring board has a microstrip line formed of an inter-layer conductor layer, a dielectric sheet, and a strip-shaped conductor film, which have substantially the same potential as the ground conductor film, and the ground conductor film and the interlayer micro-strip line. A dielectric substrate not provided with a conductor layer and a microstrip line formed of a strip-shaped conductor film having a different width on the extension of the strip-shaped conductor film.

Further, a strip-shaped conductor film provided between the first dielectric substrate and the second dielectric substrate, and the first dielectric substrate so as to sandwich the strip-shaped conductor film. And a wiring board in which a strip line is configured by a grounding conductor film provided on one surface of each of the second dielectric substrate, the first dielectric substrate and the second dielectric substrate respectively. It was composed of at least two layers of dielectric sheets. Further, a conductor layer is provided in a part between the layers of the respective dielectric sheets, and the conductor layer and the grounding conductor film are electrically connected so as to have substantially the same potential. As a result, the wiring board is a strip line composed of the conductor layers between the first dielectric substrate layers, the conductor layers between the second dielectric substrate layers, the dielectric region between them, and the strip-shaped conductor film. A first dielectric substrate and a second dielectric substrate not provided with a conductor layer between them, a grounding conductor film of the first dielectric substrate, and a grounding conductor of the second dielectric substrate On the extension of the film and the strip-shaped conductor film, a strip line composed of strip-shaped conductor films having different widths is formed.

According to another aspect of the invention, a conductive substrate, a first dielectric substrate having an opening for mounting a semiconductor element on the conductive substrate, and a periphery of the first dielectric substrate are provided. It is composed of a second dielectric substrate above which is provided with an opening larger than the opening and a partial cutout, and a grounding conductive provided on the conductive substrate side of the first dielectric substrate. A microstrip line is formed by the body film and a strip-shaped conductor film provided on the surface facing the grounding conductor film, and the microstrip line is formed on the grounding conductor film and the upper surface of the second dielectric substrate. A strip line is formed by the provided conductor film and the strip-shaped conductor film provided between the layers of the first dielectric substrate and the second dielectric substrate, and the microstrip line and the strip line are extended. Provided on the conductor film above In high-speed IC package consisting of attributes of the lead, the first dielectric substrate is at least 2
It was composed of layers of dielectric sheets. Further, a conductor layer is provided in a part between layers of the dielectric sheet, and the conductor layer and the grounding conductor film are electrically connected so as to have substantially the same potential. As a result, the wiring portion and the terminal portion of the high-speed IC package are connected to the microstrip line including the conductor layer, the dielectric sheet, and the strip-shaped conductor film, and the grounding conductor provided on the first dielectric substrate. And a grounding conductor film provided on the upper surface of the film and the second dielectric substrate, and a strip-like conductor film extending on the strip-like conductor film and having a width different from that of the conductor film. On the extension of the strip line, the grounding conductor film provided on the first dielectric substrate, the first dielectric substrate not provided with an inter-layer conductor layer, and the strip line conductor film for the strip line. Therefore, the microstrip line is formed of a strip-shaped conductor film having a width different from that of the conductor film.

[0009]

According to the present invention, as described above, the dielectric substrate has a structure in which at least two layers of dielectric sheets and a conductor film having substantially the same potential as the grounding conductor film are provided between the dielectric sheets. It is possible to change the wiring width of the microstrip line or the strip line on the way. Therefore, the characteristic impedance of the line can be made substantially the same while changing the width of the line. Therefore, the above problems can be eliminated.

[0010]

EXAMPLES Next, examples of the present invention will be described. It is needless to say that the embodiment is merely an example, and various modifications and improvements can be made without departing from the spirit of the present invention.

(Embodiment 1) FIG. 1 is a perspective view for explaining a first embodiment of the present invention, in which 1 and 6 are first and second, respectively.
Dielectric sheet, 2 is a grounding conductor film, 3 is a conductor layer provided between two layers of dielectric sheets 1 and 6, and 4 is a connection between the conductor layer 3 and the grounding conductor film 2. Conductive vias,
Reference numeral 5 is a plane defined by AA'-B'-B which is orthogonal to the conductor layer and is in contact with the end face of the conductor layer, and 7 and 8 are strip-shaped conductor films each having a different width. It is formed on the body sheet 6. FIG. 2 is a sectional view taken along the line CC ′ of FIG. In this embodiment, a substantially uniform conductor is present on the upper surface of the first dielectric sheet 1 having the grounding conductor film 2 formed on its back surface and reaches the surface 5 of AA'-B'-B. A layer 3 is provided, and the conductor layer 3 and the ground conductor film 2 are provided.
A plurality of conductive vias 4 are provided to electrically connect the two. Another second dielectric sheet 6 is laminated on the conductor layer 3 and the dielectric sheet 1, and further, on the dielectric sheet 6, with the A-A'-B'-B surface as a boundary. And strip-shaped conductor films 7 and 8 having different widths are provided.

In such a wiring board, the conductive vias 4 are arranged so that the conductive layer 3 has substantially the same potential as the ground conductive film 2.
Are formed. Therefore, the conductor layer 3, the dielectric sheet 6 and the strip-shaped conductor film 7 constitute one microstrip line. Further, a region where the conductor layer 3 is not provided, that is, the dielectric substrate 61 including the ground conductor film 2 and the dielectric sheets 1 and 6, and the strip conductor film 8 constitute one microstrip line. It That is, a wiring board in which two microstrip lines having different line widths are connected is realized.

With such a structure, the thickness of the dielectric can be equivalently changed within the same wiring board, so that the width of the strip-shaped conductor film of the microstrip line can be easily changed. I can do it. That is, the line width can be freely selected while setting the characteristic impedance of the microstrip line to a predetermined value. As is clear from the above results, a great improvement such as an increase in the degree of freedom in designing the wiring board composed of the microstrip line was achieved as compared with the conventional technique.

(Embodiment 2) FIG. 3 is a perspective view showing a second embodiment of the present invention, and FIG. 4 is a view showing the sectional structure of FIG. 3, in which 9, 13, 16, and 18 are dielectrics. Body sheet, 10,1
Reference numeral 9 is a grounding conductor film, 11 and 17 are conductor layers formed between layers, and 12a and 20 are conductive vias. In this embodiment, the upper surface of the dielectric sheet 9 having the grounding conductor film 10 formed on one side thereof, which is the surface 1 of D-D'-E'-E.
A substantially uniform conductor layer 11 is provided up to 2, and a plurality of conductive vias 12a for electrically connecting the conductor layer 11 and the ground conductor film 10 are provided. Another dielectric sheet 13 is laminated on the conductor layer 11 and the dielectric sheet 9, and further, a width is defined on the dielectric sheet 13 with the D-D'-E'-E surface 12 as a boundary. Strip-shaped conductor films 14 and 15 are provided. The grounding conductor film 10, the dielectric sheets 9 and 13, the conductor layer 11, and the conductive via 12 are separated by the surface on which the strip conductor films 14 and 15 are formed.
A substrate obtained by mirror-projecting a substrate made of a, that is, a conductive material for electrically connecting the dielectric sheets 16 and 18, the conductor layer 17, the grounding conductor film 19, and the conductor layer 17 and the grounding conductor film 19. The substrate composed of the conductive vias 20 includes a dielectric sheet 13 and strip-shaped conductor films 14 and 1.
It is provided on top of 5. In such a configuration, one strip line is composed of the strip-shaped conductor film 14 and the dielectric substrate 62 having the conductor layers 11 and 17 arranged so as to sandwich the strip-shaped conductor film 14. Another strip line is composed of a strip-shaped conductor film 14 and a dielectric substrate 63 having grounding conductor films 10 and 19 sandwiching the conductor film 14.

With such a structure, as in the first embodiment, the thickness of the dielectric can be equivalently changed within the same wiring board, so that the strip-shaped conductive line of the strip line can be obtained. The width of the body membrane can be easily changed. That is, the line width can be freely selected while setting the characteristic impedance of the microstrip line to a predetermined value. That is, there is an advantage that the wiring design of the wiring board becomes easy.

(Embodiment 3) FIGS. 5 and 6 are a plan view and a sectional view showing the periphery of terminals of a high-speed IC package showing a third embodiment, wherein 21, 25 are dielectric sheets, 22, Reference numeral 30 is a grounding conductor film, 23 is a conductor layer provided between the dielectric sheets 21 and 25, and 24 is a conductive via for electrically connecting the grounding conductor film 22 and the conductor layer 23. , 26, 27 and 28 are strip-shaped conductor films, 29 is a metallic lead, 31 is a second dielectric substrate, 32 is a conductive substrate, and 64 is a first dielectric substrate. The basic structure is similar to that of the first embodiment. In such a configuration, the wiring board is composed of two microstrip lines and one stripline. The first microstrip line and the dielectric layer 23 are formed substantially evenly up to the plane cut by pq so as to have substantially the same potential as the grounding conductor film 22 joined to the conductive substrate 32. The body sheet 25 and the strip-shaped conductor film 26 formed on the body sheet 25. The strip line includes strip-shaped conductor films 27 having different widths on the extension of the strip-shaped conductor film 26, and a first dielectric substrate 64 and a second dielectric substrate provided so as to sandwich the strip-shaped conductor films 27. 31 and a grounding conductor film 2 formed on one surface of each of the dielectric substrate 2
It is composed of 2 and 30. The second microstrip line is an extension of the strip-shaped conductor film 27 of the strip line and has a strip-shaped conductor film 28 having a width different from that of the conductor film and the first dielectric substrate 64. And a grounding conductor film 22.

With such a structure, the width of the strip-shaped conductor film of the microstrip line can be freely changed. As a result, it is possible to make the predetermined characteristic impedance constant around the wiring and terminals of the high-speed IC package regardless of the location, and it is possible to eliminate unnecessary reflection which was a problem in the conventional package.

In the above embodiments, the description has been made on the assumption that the conductor layers provided between the layers of the two-layer dielectric sheets are formed substantially uniformly. However, the conductors other than the regions forming the microstrip line or the strip line are described. Needless to say, the mesh structure with the body layer removed does not hinder the effects of the present invention. Also, the case where the dielectric substrate is composed of a two-layer dielectric sheet has been described.
When it is desired to provide strip-shaped conductor films having three or more different widths, the dielectric substrate is composed of three or more layers, and the conductor layers provided between the layers are the strip-shaped conductor films. The position may be set to correspond to the width. That is, it is needless to say that the characteristic impedances of the lines corresponding to the widths of three or more kinds of strip-shaped conductor films may be made substantially the same, and it goes without saying that it falls within the scope of the present invention. Further, in the embodiments of the present invention, a plurality of conductive vias are used to electrically connect the conductor layer provided between the layers and the grounding conductor film, but the conductive layer is formed on the end surface of the dielectric substrate. A means for forming a body membrane may be used.

[0019]

As described above, according to the present invention,
The dielectric substrate of the wiring board is composed of at least two layers of dielectric sheets, and a spatial position having substantially the same potential as the grounding conductor film is provided between the two dielectric sheets via the conductive vias. Since the structure can be converted into the conductor layer, there is an advantage that the width of the strip-shaped conductor film of the microstrip line or the strip line can be easily changed, and the degree of freedom in designing the wiring board can be greatly improved. Also,
In the high-speed IC package, since the wiring and the terminal portion have substantially the same structure as described above, there is an advantage that not only the flexibility of the wiring design is improved but also unnecessary reflection at the terminal portion can be removed. Furthermore, by changing the number of layers of the dielectric sheet, the characteristic impedance of the microstrip line at the terminal portion is made to be almost the same as the characteristic impedance of the microstrip line in the wiring, etc., while lead connection at the terminal portion equipped with the metallic lead There is an advantage that a wiring width with sufficiently high strength can be realized. in this way,
Higher degree of freedom in wiring board design, high-speed IC compared to conventional technology
For example, the electrical characteristics of the package can be greatly improved.
High-speed operation semiconductor element is mounted on the package and 10G
The effect of the present invention is great in realizing an excellent module of b / s or more.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

FIG. 2 is a sectional view of the first embodiment of the present invention.

FIG. 3 is a perspective view of a second embodiment of the present invention.

FIG. 4 is a sectional view of a second embodiment of the present invention.

FIG. 5 is a high-speed I for explaining the third embodiment of the present invention.
It is the top view which expanded the C package terminal periphery.

FIG. 6 is a high-speed I for explaining the third embodiment of the present invention.
It is sectional drawing which expanded the C package terminal periphery.

FIG. 7 is a perspective view illustrating a conventional wiring board including a microstrip line.

FIG. 8 is a perspective view illustrating a conventional wiring board including a strip line.

FIG. 9 is a plan view illustrating a conventional general high-speed IC package.

FIG. 10 is an enlarged plan view of the periphery of terminals of the conventional package shown in FIG.

FIG. 11 is an enlarged cross-sectional view around a terminal of the conventional package shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dielectric sheet 2 Conductive film for grounding 3 Conductive layer 4 Conductive vias 5 Plane showing boundaries of lines 6 Dielectric sheet 7 Strip-shaped conductive film 8 Strip-shaped conductive film 9 Dielectric sheet 10 Grounding Conductor film 11 Conductor layer 12 Plane showing boundary of line 12a Conductive via 13 Dielectric sheet 14 Strip-shaped conductor film 15 Strip-shaped conductor film 16 Dielectric sheet 17 Conductor layer 18 Dielectric sheet 19 Ground Conductive film 20 Conductive via 21 Dielectric sheet 22 Grounding conductive film 23 Conductive layer 24 Conductive via 25 Dielectric sheet 26 Strip-shaped conductive film 27 Strip-shaped conductive film 28 Strip-shaped conductive film Film 29 Lead 30 Grounding Conductor Film 31 Dielectric Substrate 32 Dielectric Substrate 61 Dielectric Substrate 62 Dielectric Substrate 63 Dielectric Substrate 64 Dielectric substrate 101 Dielectric substrate 102 Grounding conductor film 103 Strip-shaped conductor film 104 Dielectric substrate 105 Grounding conductor film 106 Dielectric substrate 107 Grounding conductor film 108 Strip-shaped conductor film 110 Dielectric Substrate 111 Dielectric Substrate 112 Strip-shaped Conductor Film 113 Strip-shaped Conductor Film 114 Strip-shaped Conductor Film 114a Lead 116 Grounding Conductor Film 117 Dielectric Substrate

Claims (3)

[Claims] 1. A wiring in which a microstrip line is composed of a grounding conductor film provided on one surface of a dielectric substrate and a strip-shaped conductor film provided on a surface facing the grounding conductor film. In the plate, the dielectric substrate is composed of at least two layers of dielectric sheets, a conductor layer is provided in a part between layers of the dielectric sheet, and the conductor layer and the grounding conductor film have substantially the same potential. And the characteristic impedance of the microstrip line composed of the conductor layer, the dielectric sheet, and the strip-shaped conductor film is electrically connected so that Characteristics of a microstrip line including a dielectric substrate not provided with a conductor layer and a strip-shaped conductor film having a width different from the width of the conductor film on the extension of the strip-shaped conductor film. Inn Wiring board is characterized in that in roughly a same as-impedance. 2. A strip-shaped conductor film provided between layers of a first dielectric substrate and a second dielectric substrate, and the first dielectric substrate so as to sandwich the strip-shaped conductor film. And a wiring board in which a strip line is configured by a grounding conductor film provided on one surface of each of the second dielectric substrate, wherein the first dielectric substrate and the second dielectric substrate are at least The dielectric substrate according to claim 1, comprising a two-layer dielectric sheet, a conductive layer between layers, and a conductive via, and a conductive layer and a second dielectric provided on the first dielectric substrate. The characteristic impedance of the strip line formed by the conductor layer provided on the substrate and the strip-shaped conductor film provided between the first dielectric substrate and the second dielectric substrate is the first dielectric substance. Grounding conductor film and second dielectric provided on the substrate The characteristic impedance of a strip line formed of a strip-shaped conductor film having a width different from the width of the conductor film on the extension of the conductor film for grounding provided on the plate and the strip-shaped conductor film is almost the same. A wiring board characterized in that 3. A conductive substrate, a first dielectric substrate provided with an opening for mounting a semiconductor element on the conductive substrate, and a first dielectric substrate surrounding the first dielectric substrate. A second dielectric substrate provided with an opening larger than the opening and a partial cutout, and a grounding conductive film provided on the conductive substrate side of the first dielectric substrate; A microstrip line is formed by a strip-shaped conductor film provided on the surface facing the ground conductor film, and a conductor provided on the ground conductor film and the upper surface of the second dielectric substrate. A strip line is formed by a film and a strip-shaped conductor film provided between the layers of the first dielectric substrate and the second dielectric substrate, and a conductor located on an extension of the microstrip line and the strip line. Do not use metallic leads provided on the film. In a high-speed IC package, the first dielectric substrate is composed of at least two layers of dielectric sheets, and a conductor layer is provided in a part between layers of the dielectric sheet. The conductor layer and the first dielectric body are provided. A microstrip line having a structure in which grounding conductor films provided on a substrate are electrically connected to each other so as to have substantially the same potential, and comprising the conductor layer, a dielectric sheet, and a strip-shaped conductor film. Of the grounding conductor film provided on the first dielectric substrate, the grounding conductor film provided on the upper surface of the second dielectric substrate, and the extension of the strip-like conductor film. And a characteristic impedance of a strip line formed of a strip-shaped conductor film having a width different from that of the conductor film and a conductor layer between the ground conductor film and the interlayer provided on the first dielectric substrate are provided. Not first The characteristic impedance of the dielectric substrate and the characteristic impedance of the microstrip line formed of a strip-shaped conductor film on the extension of the strip-shaped conductor film for the strip line and having a width different from the width of the conductor film are almost the same. High-speed IC package characterized by the above.