JPH04326201A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the deviation of phases between a microstrip line and a ground plane and to suppress discontinuity by providing microstrip transmission lines to be close to each other and providing a side plane in contact with the ground plane. CONSTITUTION:Dielectric substrates 9 are provided on the input side and output side of a recessed part composed of Cu and provided on the inside bottom of a main body 1 of a package while providing an Au/Ni plating layer on the surface, and a microstrip transmission line 8 and an open stub pattern 10 are provided on the surface of the dielectric substrate 9. Next, a dielectric substrate 2 composed of alumina and a microstrip transmission line 4 are provided through a side wall 2 at the main body 1 of the package, and the inside top is provided in contact with the respective input side and output side end faces of the dielectric substrate 9. In this case, both the ends of the dielectric substrate 3 parallel to the microstrip transmission line 4 is formed while being sandwiched by walls (ground planes) protruded from the side plane of the recessed, part at the main body 1 of the package so as to shield radiation electromagnetic waves.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to semiconductor devices, and in particular to GaAs field effect transistors (hereinafter referred to as GaAsFE).
This invention relates to an input/output matching circuit (denoted as T).

0002

[Prior Art] A conventional semiconductor device is shown in FIGS. 2(a) and 2(b).
), the GaAsF provided in the package body 1
The 50Ω internal matching circuit of the ET chip 6 is composed of a lumped constant matching circuit using the capacitance of a chip capacitor 7 and the inductance of a thin metal wire (Au, etc.), and a dielectric substrate 9.
It is composed of a distributed constant circuit formed by a microstrip transmission line 8 and an open stub pattern 10 provided on the top,
Lead portion dielectric substrate 3 provided on the side wall of the package body 1
The inner end of the package body 1 was formed flush with the side wall of the package body 1 or recessed.

0003

[Problems to be Solved by the Invention] The above-mentioned conventional semiconductor device has a microelectronic semiconductor device provided on first dielectric substrates on each of the input side and output side, which are provided inside the package body and constitute an internal matching circuit. The electromagnetic waves propagating through the strip transmission line are grounded using the bottom of the package body.
It propagates across the dielectric and free space. Furthermore, the microstrip transmission line provided on the second dielectric substrate passing through the side wall of the package body also propagates in a similar mode.

[0004] If there is a gap between the first and second dielectric substrates, the microstrip transmission lines will inevitably be separated from each other, causing a phase shift between the microstrip transmission line and the ground plane. Put it away. Therefore, especially as the frequency becomes higher, the phase shift becomes more noticeable as the wavelength becomes shorter, causing discontinuity, which affects the matching state of GaAsFETs in the ultra-high frequency band, resulting in characteristic deterioration. was there.

[0005]

[Means for Solving the Problems] A semiconductor device of the present invention includes:
A first dielectric substrate having a microstrip transmission line and an internal matching circuit formed by an open stub pattern provided in a recess provided on the inner bottom surface of the package body, and a microstrip transmission line penetrating the side wall of the package body. and a second dielectric substrate provided in contact with an end surface of the first dielectric substrate so that its inner tip is in contact with the microstrip transmission line on the first dielectric substrate; and the second dielectric substrate. It has a microstrip transmission line and ground planes provided in contact with both parallel sides.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) and 1(b) are a plan view and a partially cutaway perspective view showing an embodiment of the present invention.

As shown in FIGS. 1(a) and 1(b), a dielectric material is placed on the input side and the output side in a recess provided on the inner bottom surface of a package body 1 made of Cu and having an Au/Ni plating layer on the surface. A substrate 9 is provided, and a microstrip transmission line 8 and an open stub pattern 10 are provided on the surface of the dielectric substrate 9. Next, a dielectric substrate 2 made of alumina and a microstrip transmission line 4 are provided through the side wall 2 of the package body 1, and their inner tips are in contact with the input side and output side end surfaces of the dielectric substrate 9, respectively. establish. Here, both ends of the dielectric substrate 3 parallel to the microstrip transmission line 4 are sandwiched between walls (ground planes) protruding from the side surfaces of the recessed portion of the package body 1, so that radiated electromagnetic waves can be blocked. Next, leads 11 are connected to each of the input end and output end of the microstrip transmission line 4. Next, a GaAsFET chip 6 is mounted at the center inside the package body 1, a chip capacitor 7 is mounted on each of the input side and output side of the GaAsFET chip 6, and the chip capacitor 7 is mounted between the GaAsFET chip 6 and the chip capacitor 7. and the microstrip transmission line 8, and between the microstrip transmission line 8 and the microstrip transmission line 4 are connected by thin metal wires to form a semiconductor device.

[0009]

Effects of the Invention As described above, the present invention provides an internal matching microstrip that is provided on the bottom surface of the package body by connecting the inner end surface of the dielectric substrate having the microstrip transmission line that penetrates the side wall of the package body. By providing it in contact with each of the input end and output end of the dielectric substrate having the strip transmission line, and by providing the side surface in contact with the ground plane,
This has the effect of reducing the phase shift between the microstrip line and the ground plane and suppressing discontinuity.

[Brief explanation of drawings]

FIG. 1 is a plan view and a partially cutaway perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view and a partially cutaway perspective view showing an example of a conventional semiconductor device.

[Explanation of symbols]

1 Package body 2 Side walls 3, 9 Dielectric substrate 4, 8 Microstrip transmission line 6
GaAsFET chip 7 Chip capacitor 10 Open stub pattern 11 Lead

Claims (1)

[Claims] 1. A first dielectric substrate provided in a recess provided on the inner bottom surface of a package body and having an internal matching circuit formed by a microstrip transmission line and an open stub pattern, and a microstrip that passes through a side wall of the package body. a second dielectric substrate having a transmission line and provided in contact with an end surface of the first dielectric substrate so that its inner tip is in contact with the microstrip transmission line on the first dielectric substrate; 1. A semiconductor device comprising: a microstrip transmission line of a second dielectric substrate; and ground planes provided in contact with both parallel sides of the dielectric substrate.