TECHNICAL FIELD

The present invention rerates to a radio communication module.

This application claims priority from Japanese Patent Application No. 2020-091692 filed on May 26, 2020, the contents of which are incorporated herein by reference in their entirety.

BACKGROUND ART

Patent Document 1 discloses a radio communication module including an antenna substrate (first dielectric substrate) having an antenna element and an RFIC mounted on the antenna substrate.

PRIOR ART DOCUMENTS

Patent Documents

[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2019-97026

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

In order to ensure performance a radio communication module, it is required to effectively dissipate heat from an RFIC and cool down the RFIC. In the configuration disclosed in Patent Document 1, since an RFIC is directly mounted on an antenna substrate, there is a case where it is difficult to ensure a heat dissipation route due to the reason that wirings of the antenna substrate are densely disposed thereon.

The invention was made in view of the above-described situation, and has an object to provide a radio communication module that ensures a heat dissipation route of an RFIC and can effectively cool down the RFIC.

Means for Solving the Problems

In order to solve the above-described problems, a radio communication module according to an aspect of the invention includes: a mounting substrate having a first surface and a second surface; an antenna substrate mounted on the first surface; and an IC package that is mounted on the second surface and includes an RFIC. The mounting substrate includes a heat-dissipation via hole that penetrates through the mounting substrate and extends between the first surface and the second surface, a heat dissipation pattern that is formed on the first surface and is connected to the heat-dissipation via hole, and a non-heat-dissipation via hole that transmits an electrical signal or electrical current, which are formed on thereon. In a plan view when viewed from the thickness direction of the mounting substrate, the heat-dissipation via hole is connected to the RFIC at a position at which the heat-dissipation via hole overlaps the RFIC, and the heat dissipation pattern extends to an outside of the antenna substrate.

According to the aforementioned aspect, the mounting substrate is prepared differentially from the antenna substrate, and the heat-dissipation via hole is disposed on the mounting substrate at the position at which the heat-dissipation via hole overlaps the RFIC when viewed in a plan view. Consequently, wirings of the antenna substrate are not densely disposed thereon, and heat generated from the RFIC is effectively transmitted to the heat-dissipation via hole. Furthermore, the heat-dissipation via hole is connected to the heat dissipation pattern, and the heat dissipation pattern extends to the outside of the antenna substrate when viewed in a plan view. Because of this, it is possible to form the heat dissipation pattern on a wide region of the first surface of the mounting substrate. As mentioned above, a heat dissipation route is ensured by use of the heat-dissipation via hole and the heat dissipation pattern, heat is dissipated to air via the heat dissipation pattern, and therefore it is possible to effectively cool down the RFIC.

Here, a gap may be provided between the antenna substrate and the mounting substrate.

Additionally, the antenna substrate includes a second heat dissipation pattern that is formed on an opposed face of the antenna substrate which faces the mounting substrate, and the second heat dissipation pattern may be connected to the heat dissipation pattern.

Furthermore, an underfill are provided around a connection portion between the second heat dissipation pattern and the heat dissipation pattern, and the underfill may be in contact with the second heat dissipation pattern and the heat dissipation pattern.

Moreover, a plurality of connection portions are provided, each of which connects the second heat dissipation pattern to the heat dissipation pattern, and when viewed in a plan view, the plurality of the connection portions may be disposed at both a central part and an outer-peripheral part of the antenna substrate.

In addition, the antenna substrate includes an antenna terminal that transmits a signal between the antenna substrate and the RFIC, and when viewed in a plan view, the antenna terminal may be disposed between the connection portion that is disposed at the central part and the connection portion that is disposed at the outer-peripheral part.

Additionally, a first heatsink member may be provided on a surface of the IC package which is opposite to the mounting substrate.

Furthermore, a second heatsink member may be provided at a position different from the antenna substrate on a surface of the heat dissipation pattern in the plan view.

Additionally, the heat dissipation pattern may have the same electrical potential as that of GND.

Effects of the Invention

According to the above-mentioned aspect, it is possible to provide a radio communication module in which wirings of the antenna substrate are not densely disposed thereon, the heat dissipation route of the RFIC is ensured, and it is possible to effectively cool down the RFIC.

