JP2000100992A - High frequency package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To build an RF element filter in a DC power supply line of a package and stabilize the operation of a semiconductor element within the package, without increasing the size and cost by providing a dielectric board with a DC power supply line, and providing it with an open line connected to the DC power supply line. SOLUTION: A dielectric board is made by stacking the two dielectric boards the same in thickness composed of a first dielectric board 3-1 and a second dielectric board 3-2. Then, an open line 8, which has a length quarter the wavelength of the signal of high frequency of microwave band to milliwave, is made between the layers of the first board 3-1 and the second board 3-2. The open line 8 is connected to a DC power power cable 7 through a through hole 9. Hereby, it becomes constitution fit for high frequency band from microwave to milliwave band. Moreover, an RF element filter can be integrated into the DC power cable of the package without raising the size or the cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high-frequency package for surrounding and protecting a semiconductor device, and more particularly to a high-frequency package used in a high frequency band from a microwave band to a millimeter wave band.

[0002]

2. Description of the Related Art FIG. 4 shows an example of the structure of a general high-frequency package. In FIG. 4, 3 is a dielectric substrate made of a dielectric material, and 4 is a dielectric wall made of the same dielectric material. These dielectric members constitute a cavity. Reference numeral 5 denotes a metal wiring (hereinafter, referred to as RF) for transmitting a high frequency (RF) electric signal from the outside of the cavity to the inside through the dielectric wall 4.
Reference numeral 6 denotes a high frequency (R) which penetrates through the dielectric wall 4.
F) Metal wiring (hereinafter, RF output line) for transmitting an electric signal from the inside of the cavity to the outside, and 7 is a dielectric wall 4
And a metal wiring (hereinafter referred to as a DC power supply line) for transmitting direct current (DC) power from the outside of the cavity to the inside.
1 is a semiconductor element, which is mounted inside the cavity,
The RF input line 5, by the bonding wire 2, etc.
It is electrically connected to the RF output line 6 and the DC power supply line 7. After mounting the semiconductor element 1, the cavity is hermetically sealed using a lid made of a metal plate or the like. As described above, the semiconductor element 1 can operate by obtaining the RF electric signal and the DC power while being safely protected.

In such a package, it is known that the following problems often occur as the operating frequency of the internal semiconductor element 1 increases.

That is, originally, the RF input line 5 and the RF output line 6
The high-frequency electric signal (leakage of the RF electric signal) which must flow only on the DC power supply line 7 leaks out. As shown in FIG. 5, the high-frequency electric signal leaked to the DC power supply line is
By leaking to the RF input circuit through the power supply circuit, a closed loop is formed outside the package, and as a result, the semiconductor element 1 causes unstable operation such as oscillation.

In order to avoid the above-mentioned problem, a method of adding an RF blocking filter to the DC power supply line 7 has conventionally been adopted. The RF blocking filter is usually provided in a DC power supply circuit inside the semiconductor element 1. However, in order to further stabilize the operation, the DC power supply line 7 on the package is used.
May also be provided on the top.

An example in which an RF blocking filter is provided on a DC power supply line 7 on a package is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-225.
No. 449, JP-A-4-162557 and the like. In JP-A-60-225449, a spiral inductor is formed only by a metal wiring pattern formed on a package by printing or the like, and this is used as a high-frequency blocking filter. In Japanese Patent Application Laid-Open No. 4-162557, a high-pass filter is realized by adding a ferrite core to a package.

[0007]

However, the method of forming a spiral inductor by metal wiring as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 60-225449 has a problem that the size of the package is increased. Further, there is a problem that the spiral inductor no longer functions normally as an inductor in a microwave band to a millimeter wave band having a very short wavelength.

Further, the method of adding a ferrite core or the like as disclosed in Japanese Patent Application Laid-Open No. 4-162557 has a problem that the size of the package is increased and the cost is increased. There was a problem that the number of steps of package manufacturing also increased.

The present invention has been made to solve the above problems, and an object of the present invention is to incorporate an RF blocking filter in a DC power supply line of a package without increasing the size and cost. Thereby, it is intended to stabilize the operation of the semiconductor element inside the package. In this case, it is another object of the present invention to use a filter structure suitable for a high frequency band from a microwave band to a millimeter wave band as an RF blocking filter.

[0010]

A high-frequency package according to the present invention is a high-frequency package in which a semiconductor element is mounted at least inside a cavity using a dielectric substrate, and a DC power supply for supplying DC power to the semiconductor element. An electric wire is provided on the dielectric substrate, and an open line connected to the DC power supply line is provided.

Further, in the high frequency package of the present invention, the dielectric substrate is constituted by a multilayer substrate, the open line is formed at a position of an inner layer of the multilayer substrate, and a through hole is formed between the dielectric substrate and the DC power supply line. It is characterized by being electrically connected via a hole.

[0012]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. FIG. 1A is an overhead view of the entire package, and FIG. 1B is an enlarged view of a part in which an RF blocking filter is incorporated in a DC power supply line. In FIG. 1, the same members as those in FIG. 4 are denoted by the same reference numerals. In FIG. 1, a dielectric substrate 3 includes a first dielectric substrate 31 and a second dielectric substrate 32.
Are formed by laminating two dielectric substrates having the same thickness. In FIG. 1, reference numeral 8 denotes a microwave band to a millimeter wave band formed on the back side of the substrate with the dielectric substrate 32 interposed therebetween, that is, a layer formed between the first substrate 31 and the second substrate 32. This is an open line having a length of about に 対 し て with respect to the wavelength λ of a signal in a high frequency band. This open line 8 is connected to a DC power supply line 7 via a through hole 9.

FIG. 2 is an equivalent circuit diagram of the RF blocking filter of the embodiment of FIG. Therefore, the circuit in this part has the inductance effect 10 of the through hole and the open line 8.
Together with the length of the wavelength band, it functions as a band rejection filter in a frequency band that is a quarter of the wavelength λ.

In a circuit having a frequency of about 10 GHz or more, the length of about λ / 4 is about several mm at most. Further, in the present invention, the open line having a length of about λ / 4 is formed by laminating the DC power supply line in the thickness direction of the substrate. Therefore, an RF blocking filter can be realized without increasing the external dimensions of the package.

FIG. 3 is an example of a graph showing the performance of the RF blocking filter according to the embodiment of FIG. In FIG. 1B, the dimensions of each part are as follows: the height A of the dielectric substrate is 0.6 mm;
DC feed line width B is 0.6mm, open line length C
Is 1.5 mm, and the diameter of the through hole is 0.2 mm. As a dielectric material, an alumina substrate having a relative dielectric constant of about 9.8 was used. As is clear from the figure, the frequency 17G
In the vicinity of Hz, an attenuation characteristic of about 13 dB is obtained with respect to S21, and the performance of the RF blocking filter using the open line as in the present embodiment is particularly excellent in the frequency band from microwave to millimeter wave. It shows that it has various characteristics.

[0016]

The structure of the RF blocking filter according to the present invention is suitable for a high frequency band from the microwave band to the millimeter wave band. Further, according to the present invention, without increasing the size and cost, the R
An F rejection filter can be incorporated. As a result, instability such as oscillation of the semiconductor element mounted inside the package can be suppressed.

[Brief description of the drawings]

FIG. 1 is an overhead view of a structure of a package according to the present invention and an enlarged view of an RF blocking filter unit.

FIG. 2 is an equivalent circuit diagram of the RF blocking filter of the present invention.

FIG. 3 is an example of a graph showing the performance of an RF blocking filter according to the present invention.

FIG. 4 is an overhead view of the structure of a general package of the related art.

FIG. 5 is a schematic diagram illustrating a mechanism in which a semiconductor element performs an unstable operation through a DC power supply line.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 semiconductor element 2 bonding wire 3 dielectric substrate 31 first dielectric substrate 32 second dielectric substrate 4 dielectric wall 5 RF input line 6 RF output line 7 DC feed line 8 open line 9 through hole 10 through hole Inductance effect

Claims (2)

[Claims] 1. A high-frequency package in which a semiconductor element is mounted at least inside a cavity using a dielectric substrate, wherein a DC feed line for supplying DC power to the semiconductor element is provided on the dielectric substrate. A high-frequency package comprising an open line connected to a DC power supply line. 2. The dielectric substrate is formed of a multilayer substrate, the open line is formed at a position of an inner layer of the multilayer substrate, and an electrical connection between the dielectric substrate and the DC power supply line is provided through a through hole. The high-frequency package according to claim 1, wherein the high-frequency package is connected to the high-frequency package.