JPH03206653A - Ceramic treatment for electronic component - Google Patents

Abstract

PURPOSE:To prevent a large conductor loss or a large reflection of a high-frequency signal at the halfway part of a transmission line and to prevent a crack by a method wherein the transmission line of a ceramic terminal is formed in the same width over its whole length and the thickness of an upper arm and a lower arm is made identical. CONSTITUTION:At a terminal main body 100 whose cross-section forms a cross and which is composed of a ceramic, the thickness of its right arm and its left arm 120a, 120b is formed to be in A. The height from the surface of the arms 120a, 120b to the upper end face of an upper arm 140a extended to their upper part is formed to be in 2A; the height from the rear surface of the arms 120a, 120b to the lower-end face of a lower arm 140b extended to their lower part is formed to be in A. In addition, the width of a metallized transmission line 200 which is passed through directly under the upper arm 140a and which is formed in the transverse direction on the surface of the arms 120a, 120b is formed to be in the same width B which is close to A; in the same manner, a metallized ground layer 300 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a ceramic terminal equipped with a transmission line for transmitting high frequency signals.

[Prior Art] Conventionally, as the above-mentioned ceramic terminal, the ceramic terminal shown in FIGS.
There are those shown in Fig. 1 and Fig. 11.

This ceramic terminal will be explained below.

This ceramic terminal 1000 has a terminal main body 1o having a convex cross section, which is made by laminating a narrow band-like upper ceramic member l4 having a thickness A in the vertical direction at the center of the upper surface of a wide band-like lower ceramic member l2 having a thickness A. and the upper ceramic member 1
A transmission line 20 made of metallized material such as tungsten or molybdenum is provided in the horizontal direction on the upper surface of the lower ceramic member 12 by passing directly under the terminal body 1o, and the transmission line 20 has a width of B, which is close to the width of the terminal body 1o. It consists of a ground layer 3o made of metallization provided so as to continuously cover the upper end surface of the surrounding upper ceramic member 14, the lower end surface of the lower ceramic member 12, and the front and rear end surfaces of the terminal body 10.

The transmission line 2 directly below the upper ceramic member 14
0 is formed into a strip line, and the other transmission lines 20 are formed into microstrip lines.

Further, the width of the transmission line 20 directly under the upper ceramic member l4 is shaped to a width of 172B, and the characteristic impedance of the transmission line 20 consisting of the strip line and the microstrip line is uniformly maintained at a constant value. and,
The transmission line 20 is designed to be able to transmit high frequency signals with little transmission loss.

This ceramic terminal 1000 is used for input/output to connect the inside and outside of the metal package 40, which is made of metal and houses elements such as optical elements and hybrid high-frequency elements, as shown in FIGS. 13 and 15. Used when equipped with a transmission line.

An example of its use will be explained below.

As shown in FIGS. 12 and 13, and FIGS. 14 and 15, a through hole 42 for fitting the ceramic terminal is provided in the side wall of the metal package 40. Then, the ceramic terminal 1000 is fitted into the through hole 42, and the periphery of the terminal is airtightly brazed to the inner peripheral surface of the through hole 42 and the upper surface of the bottom plate 44 of the metal package connected thereto, via the ground layer 30. . In addition, an external lead 50 is brazed to the transmission line 20 exposed on the outer upper surface of the lower ceramic member l2,
Transmission line 2 exposed on the inner upper surface of the lower ceramic member 12
An electrode (not shown) of an element housed inside the metal package 40 is connected to the metal package 40 via a wire (not shown) or the like.

Then, a high frequency signal is transmitted from the outside of the metal package 40 to the electrode of the element inside the metal package 40 via the external lead 50, the transmission line 20 of the ceramic terminal, the wire, etc., or conversely, a high frequency signal is transmitted from the electrode of the element to the outside of the metal package 40. It can also send signals.

Problem 1 to be Solved by the Invention Incidentally, in the ceramic terminal 1000, the width of the transmission line 20 directly under the upper ceramic member 14 is narrowed to 1/2B width compared to the B width of the other transmission lines 20. Therefore, the conductor loss of the high frequency signal transmitted through the narrow transmission line 20 made of high resistivity metallization becomes large.
High frequency signals could not be efficiently transmitted through the transmission line 20.

Further, as shown in FIG. 9, the narrow transmission line 20
There is a step at the boundary 22 between the transmission line and other transmission lines, and the high frequency signal is reflected at the boundary 22.
High frequency signals could not be efficiently transmitted through the transmission line 20 located at the boundary portion 22.

Furthermore, since the area of the lower end surface of the lower ceramic member l2 is wider than the upper end surface of the upper ceramic member 14, the area around the ceramic terminal 1000 is brazed to the inner peripheral surface of the through hole 42 of the metal package through the ground layer 30. When you do,
An unbalanced bonding force is applied from the metal package 40 to the bottom end surface of the ceramic terminal 1000, and cracks may occur in the ceramic terminal 1000. This is especially true when the ceramic terminal 1000 is long or as shown in FIGS.
This was likely to occur when a wide area was brazed to the inner peripheral surface and the upper surface of the bottom plate 44 of the metal package connected thereto.

Here, the ceramic terminals shown in FIGS. 16 and 17 can be considered as ceramic terminals that solve the above two problems.

In this ceramic terminal 1001, the transmission line 20 is formed to have the same width B over its entire length.

Further, the thickness of both the upper and lower ceramic members 14 and 12 is 2A, and a ground layer 30 made of metallization is provided on the upper end surface of the upper ceramic member 14, the lower end surface of the lower ceramic member 12, and the front and rear end surfaces of the terminal body 10. Continuously equipped. Furthermore, a ground layer 30 is provided in the vertical direction in the middle of the lower ceramic member 12, which is a distance A downward from the transmission line 20 exposed on the upper surface of the lower ceramic member 12 on both sides of the upper ceramic member 14. . Then, the characteristic impedance of the transmission line 20 formed on the strip line directly below the upper ceramic member 14 and the transmission line 20 formed on the microstrip line exposed on the upper surface of the other lower ceramic member 12 is made uniform over the entire length. It is held at a constant value.

However, in this ceramic terminal 1001, the ground layer 3 provided in the middle part of the lower ceramic member l2
0 end reaches the side surface of the lower ceramic member l2, and the end of the ground layer 30 is exposed when the ceramic terminal 1001 is manufactured by laminating and firing a plurality of green sheets. Ceramic from the middle to the lower part. The ivy member l2 is separated into the upper and lower parts to form the ceramic terminal 10.
There is a risk that the airtightness of 01 will be impaired.

In addition, its cross-sectional shape is the same convex shape as the conventional one, and when the periphery of the ceramic terminal 1001 is brazed to the inner peripheral surface of the through hole 42 of the metal package, the ceramic terminal 10
There is a possibility that an unbalanced bonding force is applied from the metal pano cage 40 to the upper and lower end surfaces of the ceramic terminal 1001, causing cracks in the ceramic terminal 1001.

The present invention has been made in view of these problems, and it is an object of the present invention to provide a ceramic terminal that does not have the above-mentioned drawbacks.

[Means for Solving the Problems] In order to achieve the above object, the ceramic terminal of the present invention is a terminal body made of ceramic and having a cruciform cross section,
The thickness of the left and right arms is A, the height of the upper arm from the upper surface of the left and right arms to the upper end thereof is 2A, and the height of the lower arm from the lower surface of the left and right arms to the lower end thereof is A, A transmission line consisting of a terminal main body whose upper and lower arms have the same thickness, and a metallization line which passes directly under the upper arm and is located on the same plane in the lateral direction of the upper surface of the left and right arms and has the same width, is characterized by comprising a transmission line with a width B close to the A, and a ground layer made of metallization provided continuously on the upper end surface of the upper arm, the lower end surface of the lower arm, the lower surface of the left and right arms, and the front and rear end surfaces of the terminal body. .

[Function] In the ceramic terminal having the above configuration, the width of the transmission line made of the metallization is not narrowed in the middle part, but is wide and the same width B over the entire length. .

Therefore, a high frequency signal transmitted through the transmission line does not suffer from large conductor loss in the middle of the transmission line or is reflected in the middle of the line.

In addition, the thickness of the upper and lower arms of the ceramic terminal is the same, and the upper end surface of the upper arm and the lower end surface of the lower arm are formed to the same size. When brazing the ceramic terminal through the layers, cracks will not occur in the ceramic terminal due to unbalanced bonding force being applied from the metal package to the upper and lower end surfaces of the ceramic terminal.

Furthermore, a ground layer is provided parallel to the signal line above and below the transmission line directly under the upper arm at a distance of 2A, and the transmission line is formed into a strip line, and the transmission line is exposed on the upper surfaces of the left and right arms on both sides of the upper arm. A ground layer is provided parallel to the transmission line at a distance A below the line, and the transmission line is formed into a microstrip line, and the transmission line has the same width close to A above over its entire length. B, and the characteristic impedance of the transmission line consisting of the strip line and microstrip line is maintained at a constant value over its entire length, so that high frequency signals can pass through the transmission line with less transmission loss. Conveyed.

"Example] Next, embodiments of the present invention will be described with reference to the drawings.

1 and 2 show a preferred embodiment of the ceramic terminal of the present invention, FIG. 1 being a partially cutaway view thereof, and FIG. 2 being a sectional view taken along line XX in FIG. 1. The embodiment shown in this figure will be described below.

In the figure, 100 is a terminal body made of ceramic and having a cross-shaped cross section. This terminal body 100 is formed by laminating and firing a plurality of ceramic green sheets. The left and right arms 120a extend to both sides thereof.
The thickness of the upper arm 120b is A, and the height from the upper surface of the left and right arms 120a, 120b to the upper end surface of the upper arm 140a extending upward is 28, and the lower arm 140b extends downward. The height from the lower surface of the left and right arms 120a, 120b to the lower end surface thereof is set to A, and the thickness of the upper and lower arms 140a, 140b is set to be the same.

200 passes directly under the two arms 140a of the terminal body, and connects the left and right arms 120a. 120b is a transmission line made of metallization of tungsten, molybdenum, etc. located on the same plane and provided in the lateral direction of the upper surface, and the width thereof is formed to be the same width B close to the above-mentioned A over the entire length. .

300 is a ground layer made of metallized tungsten, molybdenum, or the like. The ground layer 300 and the transmission line 200 are formed on the terminal body 100 at the same time as the terminal body 100 is formed, or are formed on the terminal body 100 after the terminal body 100 is formed. This ground layer 300 is connected to the upper arm 1 around the terminal main body 100.
40a seventh end surface, lower arm 140b lower end surface, left and right arms 120a,
It is provided on the lower surface of 120b and the front and rear end surfaces of the terminal body 100 so as to continuously cover them.

The ceramic terminal 2000 shown in FIGS. 1 and 2 is as follows.
It is structured like 12.

Next, an example of its use will be explained.

As shown in Figures 3 and 4, the metal pano cage 40
A through hole 420 into which the ceramic terminal 2000 can be inserted is provided in the middle of the side wall of the ceramic terminal 2000. Alternatively, as shown in FIGS. 5 and 6, at the bottom of the side wall of the metal package 400,
A through hole 422 is provided whose lower edge reaches the upper surface of the bottom plate 440 of the metal package. And those through holes 420.42
2, the ceramic terminal 2000 is fitted over the ceramic terminal 2000, and the through holes 420, 42 are formed around the terminal via the ground layer 300.
2 Inner peripheral surface and the bottom plate 440 of the metal package connected to it
Braze the top surface airtight.

Then, the upper and lower arms 14Qa, + of the ceramic terminal 2000
The upper arm 14.40b has the same thickness. 0 a-
Since the end face of the ceramic terminal 2000 and the lower end face of the lower arm 140b are formed to have the same size, an unbalanced bonding force is not applied from the metal package 400 to the lower end face of the ceramic terminal 2000.
The periphery of the ceramic terminal 2000 is hermetically brazed to the inner peripheral surfaces of the through holes 420 and 422 via the ground layer 300.

In addition, the left and right arms 1 located outside the ceramic terminal 2000
An external lead 500 is brazed to the transmission line 200 on the upper surface of one arm of 20a and 120b, and a ceramic terminal 2000 is
An electrode (not shown) of an element housed inside the package 400 is connected to the transmission line 200 on the upper surface of the other of the left and right arms 120a, 120b located inside, via a wire (not shown) or the like. Further, the upper surface of the metal pano cage 400 is covered with a metal cap (not shown), and the periphery of the cassop is joined to the upper end surface of the package 400 by soldering or seam welding, so that the upper surface of the metal pano cage 400 is airtightly covered with the cap. Seal it in.

Then, the element can be hermetically sealed inside the metal bath cage 400. At the same time, high-frequency signals are transmitted from the outside of the metal package 400 to the electrodes of the elements inside the metal package 400 via the external leads 500, the transmission line 200 of the ceramic terminal, wires, etc., and vice versa. can transmit high-frequency signals to

7 and 8 show other preferred embodiments of the ceramic terminal of the present invention, with FIG. 7 being a perspective view thereof, and FIG. 8 being a side sectional view showing its usage state. The embodiment shown in this figure will be described below.

In the illustrated ceramic terminal 2001, as shown in FIG. 7, the terminal body 100 made of ceramic and having a cross-shaped cross section is formed into a rectangular frame shape. Then, the left and right arms 120a, 120b are formed to have a thickness of A,
The height from the upper surface of the left and right arms 120a, 120b of the upper arm 140a to the upper end surface thereof is 2A, and the lower arm 140
The height from the lower surface of the left and right arms 120a, 120b of the left and right arms 120b to the lower end surface thereof is set to A, and the upper and lower arms 14. Oa, 1
40b are formed to have the same thickness.

Also, upper arms 140 located on the left and right sides of the terminal main body 100
A transmission line 200 made of metallization of the same width and located on the same plane in the lateral direction of the upper surfaces of the left and right arms 120a and 120b passing directly under A, and having a width B that is close to the width A. We are prepared.

Furthermore, the upper end surface of the upper arm 140a, the lower end surface of the lower arm 140b, the left and right arms 120a. 120b bottom surface and terminal body 100
(The front and rear end surfaces here refer to the front and rear end surfaces of the terminal body 100.
Front and rear upper and lower arms 140a. A ground layer 300 made of metallization is continuously provided on the outer surface of the arm 140b, the upper and lower surfaces of the left and right arms 120a and 20b connected thereto, and the outer surface thereof.

The ceramic terminal shown in FIG. 7 is constructed as described above.

Next, an example of its use will be explained.

As shown in FIG. 8, the bottom of the rectangular frame-shaped ceramic terminal 200 1 is covered with a metal bottom plate 440,
The periphery of the bottom plate 440 is brazed to the lower end surface of the lower arm l4ob via the ground layer 300, and the bottom of the ceramic socket terminal 2001 is hermetically sealed with the bottom plate 440. Then, the element 600 is mounted on the bottom plate 440 inside the ceramic terminal. In addition, the left and right arms l20a located on the outside of the ceramic terminal 2001. Transmission line 20 on the upper surface of one arm of 120b
Braze the external lead 500 to the ceramic terminal 2.
00 1 Left and right arms 120a located inside. The electrode 620 of the element housed inside the ceramic terminal 200I is connected to the transmission line 200 on the upper surface of the other arm of the ceramic terminal 120b via a wire 700 or the like. Further, the upper surface of the ceramic terminal 200 1 having a rectangular frame shape is covered with a metal cap 800, and the upper arm 1 of the ceramic terminal 1 is placed around the cap 800.
The cap 800 is soldered to the upper end surface of the ceramic terminal 2001 via the ground layer 300, and the upper surface of the ceramic terminal 2001 is hermetically sealed.

Then, the element 600 can be hermetically sealed inside the ceramic terminal 2001. In addition, the external lead 50
0. Transmit a high frequency signal from the outside of the ceramic terminal 2001 to the electrode 620 of the element housed inside the ceramic terminal 2001 through the transmission line 200, wire 700, etc. of the ceramic terminal, or vice versa. It can transmit high frequency signals.

In addition, in the embodiment shown in the figure, a long ceramic terminal 2000.200 is provided with a plurality of transmission lines 200.
1 is shown, the present invention can also be applied to a short ceramic terminal including one transmission line 200.

"Effects of the Invention" As explained above, according to the ceramic terminal of the present invention, the transmission line can be formed to have the same width over its entire length,
It is possible to prevent large conductor loss of high-frequency signals in the middle of the transmission line, and avoid reflection of high-frequency signals in the middle of the transmission line. Further, the characteristic impedance of the transmission line formed as a strip line or a microstrip line can be accurately maintained at a constant value over its entire length. Then, high frequency signals can be efficiently transmitted through the transmission line with less transmission loss.

In addition, when the area around the ceramic terminal is brazed to the inner circumferential surface of the metal pano cage through the ground layer, the bonding force applied from the metal package to the upper and lower end surfaces of the ceramic terminal is maintained uniformly. It is possible to accurately prevent cracks from occurring in the terminals. Then, an electronic device using a highly reliable metal package or the like can be formed.

Furthermore, there is no need to provide a ground layer whose end reaches the side surface of the terminal body in the middle of the terminal body, and a highly airtight ceramic terminal can be provided.

[Brief explanation of drawings]

Figures 1 and 2 are a partially broken enlarged plan view and a cross-sectional view taken along the line X-X of the ceramic terminal of the present invention, respectively, and Figures 3 and 4 are side views showing the state in which the ceramic terminal of Figure 1 is used. A sectional view and a perspective view; FIGS. 5 and 6 are a side sectional view and a perspective view, respectively, showing how the ceramic terminal of FIG. 1 is used;
7 and 8 are respectively a perspective view of another ceramic terminal of the present invention and a side sectional view showing its usage state, and FIGS. 9 and 10 are respectively a partially cutaway enlarged plan view of a conventional ceramic terminal. Its Y-Y sectional view, Figure 11 is a perspective view of a conventional ceramic terminal, Figures 12 and 13, and Figures 14 and 15 are side sectional views showing the usage state of the ceramic terminal of Figure 11, respectively. 16 and 17 are a partially cutaway enlarged plan view of the ceramic terminal and its 2-
FIG. 2 is a sectional view. 100...Terminal body, 120a...Left arm, 120b
...Right arm, 140a... Upper arm, 140b... Lower arm, 200... Transmission line, 300... Ground layer, 400... Metal package, 500... External lead, 2000.2001. ...Ceramic terminal.

Claims (1)

[Claims] 1. A terminal body made of ceramic and having a cross-shaped cross section, the thickness of the left and right arms is A, the height from the upper surface of the left and right arms to the upper end of the upper arm is 2A, and the thickness of the left and right arms of the lower arm is A. A terminal body whose height from the lower surface of the arm to its lower end is A, and whose upper and lower arms have the same thickness, and a terminal body that passes directly under the upper arm and is located on the same plane in the lateral direction of the upper surface of the left and right arms. a transmission line made of metallization of the same width, the transmission line having a width B close to the width A;
A ceramic terminal for an electronic component, comprising a ground layer made of metallization continuously provided on the upper end surface of the upper arm, the lower end surface of the lower arm, the lower surfaces of the left and right arms, and the front and rear end surfaces of the terminal body.