JPH05199016A - Structure of package input output section for ultra high frequency band - Google Patents

Abstract

PURPOSE:To facilitate the manufacture and assembling by making a line width of a strip line section wide with respect to the structure of the package input output section for a such as a microwave band or a millimeter wave band. CONSTITUTION:First and 2nd dielectric layers 4, 5 having a length for the package input output section and a 3rd dielectric layer 6 with a length of a strip line section 3 being a component of a hermetic seal section are laminated. Moreover, lines 7, 8 of microstrip line sections 1, 2 and a line 9 of the strip line section 3 are formed on the 2nd dielectric layer 5. Ground faces 10, 11 of the microstrip line sections 1, 2 are formed between 1st and 2nd dielectric layers 4, 5, and a ground face 12 of the microstrip line section 3 is formed to an outer peripheral face of the 1st, 2nd and 3rd dielectric layers 4, 5, 6. The ground face 12 and the ground faces 10, 11 of the microstrip line sections 1, 2 are connected by a throughhole.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a package input / output section for the ultra-high frequency band such as the microwave band or the millimeter wave band. It is required that a package for an ultra-high frequency band such as a microwave band or a millimeter wave band has small insertion loss and reflection loss. Therefore, in the package input / output section, a strip line is often used for hermetic sealing. The strip line needs to have a smaller line width than the microstrip line when the lines have the same dielectric thickness and the same characteristic impedance.
When the line width is small in this way, the conductor loss generated there becomes large, and thus the line insertion loss becomes large. Therefore, there is a demand for a structure capable of making the strip line width as large as possible.

[0002]

2. Description of the Related Art In the conventional package input / output unit for the ultra-high frequency band, a line is formed between a lower dielectric substrate and an upper dielectric substrate for hermetic sealing, and the outer peripheral surface is used as a ground plane. The strip line is used to connect the internal circuit of the package and the external circuit of the package.The micro strip line is formed on the dielectric substrate, and the micro strip line is installed on both sides of the strip line. A relatively large number of combined configurations are adopted.

In order to increase the line width of the strip line for the purpose of reducing the insertion loss in the package input / output section, (1) the dielectric constant of the dielectric substrate is reduced. (2) Increase the thickness of the dielectric substrate. Means can be considered. The means (1) can be used in a microwave band or a millimeter wave band with a low dielectric constant material, while alumina ceramic which is a commonly used dielectric substrate material has a dielectric constant of about 9.5 to 10. Has a dielectric constant of 5 or more. In that case, the line width of the strip line is approximately doubled by using the low dielectric constant material. However, there is a limit to the dielectric constant of the low dielectric constant material that can be used, and it is difficult to use a material having a dielectric constant of about 5 or less in the microwave band or millimeter wave band due to problems such as high frequency characteristics. The means (2) utilizes the fact that the width of the line used increases in proportion to the thickness of the dielectric substrate. However, a too thick substrate cannot be used to suppress the propagation of unnecessary higher-order modes in the microstrip line. Further, if the thickness of the dielectric substrate used in the circuit and the thickness of the substrate of the microstrip line of the package input / output unit are different, unnecessary reflection of signals occurs at the portion where the thickness changes.

Further, as shown in FIG. 4, the line width of the strip line can be widened by making the dielectric substrate of the strip line thicker than the dielectric substrate of the microstrip line. Was proposed first. That is, the lines 35 and 36 are formed on the dielectric substrates 31 and 32 to form a microstrip line portion, and between the lower dielectric substrate 33 and the upper dielectric substrate 34 which are thicker than these dielectric substrates 31 and 32. A line 37 is formed, a ground surface is formed on the outer peripheral surface by metallization or the like to form a strip line portion, and microstrip line portions are integrally coupled to both ends of the strip line portion to configure the input / output unit 30. is there.

The input / output section 30 is inserted into the hole of the wall section 42 around the metal substrate 41 of the package and hermetically sealed to connect the internal circuit on the dielectric substrate 43 and the line 36 of the microstrip line section. Then, a metal lid (not shown) is placed on the wall 42 to seal the inside of the package. In that case, the lower dielectric substrate 33 of the strip line portion of the input / output unit 30 is inserted into the groove 44 of the metal substrate 41, and the upper surfaces of the dielectric substrate 32 and the dielectric substrate 43 of the micro strip line portion are on the same plane. It is configured so that In this way, since the dielectric substrates 33 and 34 of the strip line portion of the input / output unit 30 can be made thicker than the dielectric substrates 31 and 32 of the microstrip line portion, the line width of the line 37 of the strip line portion can be reduced. Can be wide.

[0006]

Problems to be Solved by the Invention (1),
When the package input / output unit is configured by the means of (2), in order to widen the line width of the strip line, a dielectric substrate having a low dielectric constant is used or the thickness of the dielectric substrate is increased. However, because of their limitations, it was not easy to approach the line width of the microstrip line. In the previously proposed configuration shown in FIG. 4, the thickness of the lower dielectric substrate 33 and the upper dielectric substrate 34 forming the strip line portion is made thicker than the dielectric substrates 31, 32 of the microstrip line portion. By doing so, the width of the line 37 in the strip line portion is widened, but the groove 44 for inserting the protruding lower dielectric substrate 33 is formed in the metal substrate 41.
Must be formed on the metal substrate 41 of the package.
However, there was a drawback that the processing was complicated. Further, since the protruding lower dielectric substrate 33 is fitted into the groove 44 for assembly, there is a drawback that it is not easy to assemble the input / output unit into the package. It is an object of the present invention to provide an input / output unit that widens the strip line width and is easy to manufacture and assemble.

[0007]

The ultrahigh frequency band package input / output section of the present invention will be described with reference to FIG. 1. A stripline section 3 constituting a hermetically sealed section of the package and the stripline section 3 are described. A first dielectric layer common to the microstrip line sections 1 and 2 and the stripline section 3 in an ultra-high frequency band package input / output section having microstrip line sections 1 and 2 connected to both ends of 4 and the second dielectric layer 5 and the third dielectric layer 6 forming a part of the strip line section 3 are laminated to form a microstrip line section 1 and a line 7 of the strip line section 3. 8 and 9 are continuously formed on the second dielectric layer 5, and the ground planes 10 and 11 of the microstrip line portions 1 and 2 are formed.
Is formed between the first dielectric layer 4 and the second dielectric layer 5, and the ground surface 12 of the strip line portion 3 is laminated on the first, second and third dielectric layers 4, 5 , 6 are formed on the outer peripheral surface.

The ground planes 10 and 11 of the microstrip line sections 1 and 2 and the ground plane 12 of the microstrip line section 3 are connected by a through hole formed in the first dielectric layer 4.

[0009]

Function: The ground planes 10 and 1 are formed on the lower surface of the second dielectric layer 5.
In the microstrip line portions 1 and 2 on which the line 1 and the lines 7 and 8 are formed, the second dielectric layer 5 constitutes the dielectric substrate of the microstrip line. In addition, the first and second dielectric layers 4 and 5 and the third dielectric layer 6
In the strip line portion 3 in which the line 9 is formed between the first and second dielectric layers 4 and 5, the lower dielectric substrate and the third dielectric layer 6 are formed. Respectively constitute the upper dielectric substrates. Therefore, since the upper and lower dielectric substrates of the strip line portion 3 are made thicker, the width of the line 9 can be widened. Further, since the ground surface 12 on the outer peripheral surface of the strip line portion 3 is a metal film, a hermetic seal portion between the ground surface 12 and the metal portion of the package can be formed. In addition, the first dielectric layer 4
Is a common substrate for the microstrip line units 1 and 2 and the strip line unit 3, and since there is no protrusion at the bottom,
Easy to incorporate into the package.

Further, there is a step between the ground planes 10 and 11 of the microstrip line portions 1 and 2 and the ground plane 12 of the lower surface of the first dielectric layer 4 of the strip line portion 3,
Through holes in the first dielectric layer 4 connect the ground planes 10 and 11 between the first and second dielectric layers 4 and 5 and the ground plane 12 on the lower surface of the first dielectric layer 4. Since the ground surface 12 is connected to the metal portion of the package, the ground surfaces 10 and 11 of the microstrip line portions 1 and 2 can also be connected to the metal portion of the package via the ground surface 12. Therefore, the characteristics of the microstrip line units 1 and 2 can be maintained well.

[0011]

FIG. 1 is a perspective view of an embodiment of the present invention.
2 is a microstrip line portion, 3 is a strip line portion, 4, 5, 6 are first, second and third dielectric layers, 7,
Reference numerals 8 and 9 denote lines, and reference numerals 10, 11 and 12 denote ground planes.
The ground plane 10 is formed on the portion forming the microstrip sections 1 and 2 between the first dielectric layer 4 and the second dielectric layer 5.
11 is formed, and the lines 7 and 8 of the microstrip line units 1 and 2 and the strip line unit 3 are formed on the second dielectric layer 5.
Line 9 is formed, and the thickness of the third dielectric layer 6 is made equal to the sum of the thicknesses of the first and second dielectric layers 4 and 5. Further, the ground surface 12 is formed on the outer peripheral surface of the portions of the first, second, third dielectric layers 4, 5, 6 that form the strip line portion 3. The ground plane 12 can be formed on the entire lower surface and the entire side surface of the first dielectric layer 4. It can also be formed on the side surface of the second dielectric layer 5. Then, the ground surface 12 and the ground surfaces 10 and 11 of the microstrip line portions 1 and 2 are connected to each other by a through hole, which will be described later, formed in the first dielectric layer 4.

Therefore, the second dielectric layer 4 serves as a dielectric substrate for the microstrip line, the first and second dielectric layers 4, 5 serve as the lower dielectric substrate for the strip line, and the third dielectric layer 6 Serves as the upper dielectric substrate of the strip line, and in the strip line portion 3, the thickness of the dielectric substrate can be increased, so that the width of the line 9 can be increased. Therefore, when the characteristic impedances of the microstrip line units 1 and 2 and the characteristic impedance of the strip line unit 3 are made equal,
The line widths of the lines 7 and 8 and the line 9 of the strip line portion 3 can be approximated, the change of the propagation mode due to the change of the shape can be reduced, and the reflection loss can be reduced.

FIG. 2 is a sectional view of an embodiment of the present invention.
1A is a vertical cross-sectional view, FIG. 1B is a horizontal cross-sectional view of the strip line portion 3, and FIG. 1C is a horizontal cross-sectional view of the through hole portion of the microstrip line portion 1. The same reference numerals as those in FIG. Show. 12a is a lower ground plane, 12b is an upper ground plane, 12c and 12d are side ground planes, and 13 and 14 are ground planes.
Is a through hole.

In the strip line portion 3, as shown in (B), the lower dielectric substrate is composed of the first and second dielectric layers 4 and 5, and the upper dielectric substrate is composed of the third dielectric layer 6. And the line 9 is formed between the upper dielectric substrate and the lower dielectric substrate. Also, the lower ground surface 12a, the upper ground surface 12b, and the side ground surfaces 12c and 12d.
By these, the ground surface 12 shown in FIG. 1 is configured.

The microstrip line sections 1 and 2 are
As shown in (A) and (C), the second dielectric layer 5 is used as a dielectric substrate, and the lower part (first and second dielectric layers 4, 5) is formed.
Between the ground planes 10 and 11 and the line 7,
Thus, the first dielectric layer 4 serves as a supporting substrate in the microstrip line portions 1 and 2.

Then, the microstrip line sections 1 and 2
The ground planes 10 and 11 and the lower ground plane 12a of the strip line portion 3 are connected by through holes 13 and 14. The through holes 13 and 14 may be a plurality of through holes. Also, the ground planes 10 and 11 of the microstrip line sections 1 and 2 and the ground plane 12 of the strip line section 3 should be connected using the metallized layers on the side surfaces of the first and second dielectric layers 4 and 5. Is also possible.

The package input / output unit having the above-described structure can be manufactured, for example, as follows. That is, for the first, second, and third dielectric layers 4, 5, and 6 in the green sheet state of alumina ceramic, through holes 13 and 14 are formed in the first dielectric layer 4, and the ground plane is formed by metallization or the like. 10 and 11 and the lower ground surface 12a are formed, and the inner surface of the through holes 13 and 14 is made into a conductor or the inside is filled with a conductor, whereby the ground surface 10,
11 and the lower ground plane 12a are connected to each other, and the lines 7 and 8 of the microstrip line parts 1 and 2 and the line 9 of the strip line part 3 are formed on the upper part of the second dielectric layer 5.
The second dielectric layer 5 is overlaid on the first dielectric layer 4, the third dielectric layer 6 is overlaid thereon, and the upper ground plane 12b is formed.
The side ground planes 12c and 12d are formed by metallization or the like, and are bonded and fired so as to be integrated with each other.

FIG. 3 is an explanatory view of the embodiment of the present invention at the time of assembling the package. The same reference numerals as those in FIGS. 1 and 2 indicate the same parts, 21 is a metal substrate of the package, and 22 is a wall around the metal substrate. Part of the part, 23 is a dielectric substrate forming an internal circuit. Further, (a) is a schematic top view of the main part, and (b) is a schematic cross-sectional view of the main part. A groove into which the first dielectric layer 4 can be inserted is formed in the metal substrate 21 of the package, and the package input / output section is inserted. In this case, the groove inserts and positions the package input / output portion from the outside of the package, and the line on the dielectric substrate 23 that constitutes the internal circuit of the package and the second dielectric layer 5 of the package input / output portion. Upper track 8
Are used for facilitating the connection between the line 8 of the microstrip line portion 2 and the line of the internal circuit with the same plane as, and unlike the groove 44 shown in FIG. Since it is a groove along the line, it is easy to form the groove,
Moreover, since the input / output section may be inserted from the outside of the metal substrate 21, the assembly is easy. Further, an external circuit (not shown) is connected to the line 7 of the microstrip line section 1.

Further, the ground plane 12 on the outer peripheral surfaces of the first, second and third dielectric layers 4, 5 and 6 constituting the strip line section 3 of the package input / output section and the metal substrate 21 of the package.
And a metal portion of the wall portion 22 is hermetically sealed. Thereby, the ground surface 12 of the strip line portion 3 and the metal portion of the package are connected, and the ground surfaces 10 and 11 of the microstrip line portions 1 and 2 are also connected to the metal portion of the package through the through holes 13 and 14. Will be.

Therefore, although the package input / output section for the microwave or millimeter wave ultra-high frequency band has a minute structure, the upper and lower dielectric substrates in the strip line section 3 for hermetically sealing the metal section of the package. Is thickened to widen the width of the line 9, and the microstrip line parts 1 and 2 are
Since the lower surface of the first dielectric layer 4 as the supporting substrate is a flat surface, it can be easily mounted on the metal substrate 21 of the package.

[0021]

As described above, according to the present invention,
The second and third dielectric layers 4, 5 and 6 are laminated, the second dielectric layer 5 is used as the dielectric substrate of the microstrip line portions 1 and 2, and the first and second dielectric layers 4 and 4 are formed. 5 is used as the lower dielectric substrate of the strip line portion 3, and the third dielectric layer 6 is used as the upper dielectric substrate of the strip line portion 3. Since the thickness can be increased, the width of the line 9 is widened to eliminate the sudden change in the width of the microstrip line portions 1 and 2 from the lines 7 and 8, and the package input / output portion has characteristics for microwaves or millimeter waves. Can be improved.

The first dielectric layer 4 serving as a supporting substrate for the microstrip line portions 1 and 2 has the strip line portion 3
Of the lower dielectric substrate, the lower surface of the package input / output section is a flat surface, and for example, as shown in FIG. 4, the lower dielectric substrate of the strip line section does not have a protruding structure. There is an advantage that the package can be easily manufactured and the package can be easily mounted.

The ground planes 10 and 11 of the microstrip line sections 1 and 2 and the ground plane 12 of the strip line section 3 are connected to the through holes 13 and 14 of the first dielectric layer 4.
Even if there is a step between the ground plane 12 of the strip line section 3 connected to the metal section of the package and the ground planes 10 and 11 of the microstrip line sections 1 and 2 by connecting with each other, the ground planes 10 and 11 can be connected. Therefore, the characteristics of the microstrip line parts 1 and 2 can be maintained. Therefore, there is an advantage that it is possible to provide a package input / output unit that has a small insertion loss in the microwave or millimeter wave and is easy to manufacture.

[Brief description of drawings]

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

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

FIG. 3 is an explanatory diagram when assembling the package according to the embodiment of this invention.

FIG. 4 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1, 2 Microstrip line section 3 Strip line section 4 First dielectric layer 5 Second dielectric layer 6 Third dielectric layer 7, 8, 9 Line 10, 11, 12 Ground plane 13, 14 Through hole

Claims (2)

[Claims] 1. An ultra high frequency wave having a strip line portion (3) constituting a hermetically sealed portion of a package and microstrip line portions (1) and (2) connected to both ends of the strip line portion (3). In the band package input / output section, a first dielectric layer (4) common to the microstrip line sections (1) and (2) and the strip line section (3).
And a second dielectric layer (5) and a third dielectric layer (6) forming a part of the strip line portion (3) are laminated, and the microstrip line portions (1), (2 ) And the lines (7), (8), (9) of the strip line part (3) are continuously formed on the second dielectric layer (5), and the microstrip line part (1), The ground planes (10) and (11) of (2) are connected to the first dielectric layer (4) and the second dielectric layer (4).
And the ground plane (12) of the strip line portion (3) is formed between the first dielectric layer (4), the third dielectric layer (5), (6) The structure of the package input / output unit for the ultra-high frequency band, which is formed on the outer peripheral surface. 2. The microstrip line section (1),
The ground planes (10) and (11) of (2) and the ground plane (12) of the microstrip line portion (3) are
The structure of the package input / output unit for the ultra-high frequency band according to claim 1, wherein the structures are connected by through holes formed in the first dielectric layer (4).