Semiconductor Module

Abstract

To prevent a sudden change in the ambient temperature of electronic components inside a semiconductor module while ensuring ventilation inside the module. [Solution] A semiconductor module (1) includes a module substrate (2), electronic components (3; 4) mounted on the module substrate (2), and a metal lid (60) provided on the module substrate (2) to cover the electronic components (3; 4). The metal lid (60) has an opening (61) that penetrates the metal lid (60). The opening (61) of the metal lid (60) is provided with a rectifying plate (7) that guides the flow of outside air passing through the opening (61) so that it does not directly hit the electronic components (3; 4).

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor module. [Background technology]

[0002] A semiconductor module that performs positioning using signals from Global Navigation Satellite System (GNSS) satellites is known as a GNSS module. Generally, a multi-band GNSS module has a configuration in which electronic components required for GNSS positioning (e.g., a positioning semiconductor, a radio frequency (RF) splitter, a surface acoustic wave (SAW) filter, a temperature compensated crystal oscillator (TCXO), a flash memory, peripheral circuits, etc.) are mounted on a printed circuit board.

[0003] In addition, the GNSS module receiver and its peripheral circuitry are covered with a metal lid to improve the receiver's electromagnetic compatibility and enable it to receive weak RF signals. However, if the receiver and its peripheral circuitry are completely enclosed with a metal lid, sudden changes in the ambient temperature could cause condensation inside the lid, which could lead to a short circuit. For this reason, openings are provided in the lid to ensure ventilation inside the lid.

[0004] For example, Patent Document 1 below discloses a technique for preventing internal condensation by providing a ventilation portion in the package of a semiconductor device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-128987 Summary of the Invention [Problem to be solved by the invention]

[0006] In GNSS modules with an opening in the metal cover, the temperature around the TCXO inside the GNSS module can change suddenly due to the influence of outside air passing through the opening. When the temperature around the TCXO changes suddenly, the temperature compensation becomes excessive or insufficient, causing the reference clock to become unstable. In particular, in GNSS modules that use time as a basis for positioning, an unstable reference clock can reduce positioning accuracy.

[0007] The present disclosure has been made to solve the above-mentioned problems, and aims to prevent sudden changes in the ambient temperature of the internal electronic components while ensuring ventilation inside the semiconductor module. [Means for solving the problem]

[0008] The semiconductor module according to the present disclosure comprises a module substrate, electronic components mounted on the module substrate, a metal lid provided on the module substrate to cover the electronic components, an opening penetrating the metal lid, and a rectifying plate that guides the flow of outside air passing through the opening so as not to directly hit the electronic components. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to prevent a sudden change in the ambient temperature of the electronic components inside the semiconductor module while ensuring ventilation inside the semiconductor module. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view showing a configuration of a semiconductor module according to a first embodiment. [Figure 2] FIG. 10 is a cross-sectional view showing the configuration of a semiconductor module according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] <First Embodiment> 1 is a cross-sectional view showing the configuration of a semiconductor module 1 according to embodiment 1. In this embodiment, the semiconductor module 1 is assumed to be a GNSS module for positioning.

[0012] The semiconductor module 1 comprises a module substrate 2 serving as a base, and electronic components mounted on the module substrate 2: a positioning semiconductor 3 and a temperature-compensated crystal oscillator 4. The positioning semiconductor 3 is an integrated circuit that integrates a low-noise amplifier that amplifies RF signals from the GNSS, an analog-to-digital conversion circuit, a central processing unit, memory, a positioning engine, a power management function, and an interface function with peripheral devices. The temperature-compensated crystal oscillator 4 supplies a reference clock to the positioning semiconductor 3.

[0013] A wiring pattern (not shown) for transmitting RF signals received from GNSS satellites to electronic components and a wiring pattern (not shown) for mounting electronic components are provided on the upper surface of the module substrate 2. Furthermore, a connection terminal 5 for connecting to peripheral devices is provided on the lower surface of the module substrate 2.

[0014] In order to improve the electromagnetic compatibility of the semiconductor module 1, the wiring patterns and electronic components arranged on the module substrate 2 are covered with a metal lid 60. The metal lid 60 is mounted on the module substrate 2 in the same way as other components. An opening 61 that penetrates the metal lid 60 is provided in a part of the metal lid 60, ensuring ventilation inside the metal lid 60. This prevents condensation from forming inside the metal lid 60 even if the ambient temperature suddenly changes.

[0015] In the semiconductor module 1 according to the first embodiment, a rectifying plate 7 is provided in the opening 61 of the metal lid 60 to guide the flow of outside air passing through the opening 61. The rectifying plate 7 guides the flow of outside air passing through the opening 61 toward the inner surface 63 of the metal lid 60. This prevents the flow of outside air passing through the opening 61 from directly hitting the electronic components (the positioning semiconductor 3 and the temperature-compensated crystal oscillator 4). The installation position, installation angle (θ shown in FIG. 1 ), and length of the rectifying plate 7 are optimized so that the flow of outside air does not directly hit the positioning semiconductor 3 and the temperature-compensated crystal oscillator 4, but instead is directed toward the inner surface 63 of the metal lid 60. In order to prevent the outside air from directly hitting the positioning semiconductor 3 and the temperature-compensated crystal oscillator 4, it is preferable to install the rectifying plate 7 so that the positioning semiconductor 3 and the temperature-compensated crystal oscillator 4 are not visible from the outside through the opening 61 of the metal lid 60. That is, the rectifying plate 7 is preferably positioned so that the positioning semiconductor 3 and the temperature compensated crystal oscillator 4 are hidden by the rectifying plate 7 when the opening 61 of the metal lid 60 is viewed from the outside of the semiconductor module 1.

[0016] According to the semiconductor module 1 of this embodiment, even if cold outside air flows into the semiconductor module 1 through the opening 61 of the metal lid 60, the outside air is guided by the rectifying plate 7 and flows toward the inner surface 63 of the metal lid 60, and the temperature of the air in contact with the inner surface 63 of the metal lid 60 drops, preventing condensation on the inner surface 63 of the metal lid 60. Furthermore, because the cold outside air does not directly hit the positioning semiconductor 3 and the temperature compensated crystal oscillator 4, a sudden change in the temperature around them is suppressed, and a decrease in positioning accuracy can be prevented.

[0017] [Variations] The rectifying plate 7 does not have to be fixed to the metal cover 60, and for example, the installation angle θ of the rectifying plate 7 shown in FIG. 1 may be variable. This makes it possible to adjust the installation angle θ of the rectifying plate 7 in accordance with the environmental specifications required for the semiconductor module 1.

[0018] For example, if the installation angle θ of the rectifier plate 7 is increased (close to 90 degrees), the inside of the metal lid 60 approaches a structure in which the inside is completely closed. In this case, the electronic components inside the metal lid 60 (the positioning semiconductor 3 and the temperature compensated crystal oscillator 4) are less susceptible to the effects of outside air, but condensation is more likely to occur inside the metal lid 60, resulting in a semiconductor module 1 that is suitable for environments with little temperature change.

[0019] Conversely, when the installation angle θ of the rectifying plate 7 is made small (close to 0 degrees), the ventilation inside the metal cover 60 is improved, improving the effect of preventing condensation. Even when the installation angle θ of the rectifying plate 7 is small, a decrease in positioning accuracy can be prevented by preventing the flow of outside air from directly hitting the electronic components.

[0020] By varying the installation angle θ of the rectifying plate 7 in this way, it is possible to adjust the degree of introduction of outside air into the metal lid 60 and control the ventilation efficiency of the semiconductor module 1. This makes it possible to obtain a semiconductor module 1 that can accommodate a wide range of environmental specifications.

[0021] Furthermore, since the degree to which outside air is introduced into the metal lid 60 also varies depending on the shape of the rectifying plate 7, the shape of the rectifying plate 7 may be changed according to the environmental specifications required for the semiconductor module 1. For example, the rectifying plate 7 may be provided with elongated or round slits, and the degree to which outside air is introduced into the metal lid 60 may be adjusted by changing the number and size of the slits. Furthermore, the same effect can be achieved by arranging multiple rectifying plates 7 in line for one opening 61 and adjusting the spacing between the rectifying plates 7 or the shape of each rectifying plate 7.

[0022] <Embodiment 2> 2 is a cross-sectional view showing the configuration of a semiconductor module 1 according to embodiment 2. The configuration of semiconductor module 1 according to embodiment 2 differs from the configuration of embodiment 1 (FIG. 1) in that outer surface 62 of metal lid 60 is covered with a heat insulating cover 8 made of a material with lower thermal conductivity than the metal constituting metal lid 60. Possible materials for heat insulating cover 8 include, for example, general resin materials and engineering plastics.

[0023] According to the semiconductor module 1 according to the second embodiment, even if the temperature outside the semiconductor module 1 changes suddenly, the temperature of the metal lid 60 changes gradually. Therefore, even if the temperature outside the semiconductor module 1 drops suddenly, the temperature inside the metal lid 60 drops gradually, preventing condensation from occurring.

[0024] The heat insulating cover 8 and the rectifying plate 7 may be integrally formed. That is, the rectifying plate 7 may be a part of the heat insulating cover 8. If the heat insulating cover 8 and the rectifying plate 7 are integral, the heat insulating cover 8 will have a higher airtight seal, improving the heat insulation performance. This further improves the effect of mitigating the temperature of the metal lid 60.

[0025] Furthermore, if the straightening plate 7, which is integral with the insulating cover 8, is configured to hook onto the edge of the opening 61 when the insulating cover 8 is attached to the metal lid 60, the insulating cover 8 is locked to the metal lid 60, thereby preventing the insulating cover 8 from falling off the metal lid 60.

[0026] It is possible to freely combine the embodiments, and to modify or omit the embodiments as appropriate.

[0027] <Additional Notes> Various aspects of the present disclosure are summarized below as appendices.

[0028] (Appendix 1) a module substrate; an electronic component mounted on the module substrate; a metal cover provided on the module substrate so as to cover the electronic components; an opening extending through the metal cover; a rectifying plate for guiding the flow of outside air passing through the opening so as not to directly hit the electronic components; A semiconductor module comprising:

[0029] (Appendix 2) The rectifying plate guides the flow of the outside air toward the inner surface of the metal lid. 2. The semiconductor module of claim 1.

[0030] (Appendix 3) The installation angle of the rectifying plate is variable. 10. The semiconductor module according to claim 1 or 2.

[0031] (Appendix 4) A slit is formed in the rectifying plate. 4. A semiconductor module according to any one of claims 1 to 3.

[0032] (Appendix 5) A plurality of the rectifying plates are arranged in a row in one of the openings. 5. A semiconductor module according to any one of claims 1 to 4.

[0033] (Appendix 6) Further provided is a heat insulating cover that covers the outer surface of the metal lid and has a lower thermal conductivity than the metal lid. 6. A semiconductor module according to any one of claims 1 to 5.

[0034] (Appendix 7) The heat insulating cover and the rectifying plate are integrally formed. 7. The semiconductor module according to claim 6.

[0035] (Appendix 8) The electronic components include a positioning semiconductor and a temperature compensated crystal oscillator. 8. A semiconductor module according to any one of claims 1 to 7. [Explanation of symbols]

[0036] 1 semiconductor module, 2 module board, 3 positioning semiconductor, 4 temperature compensated crystal oscillator, 5 connection terminal, 60 metal lid, 61 opening, 62 outer surface of metal lid, 63 inner surface of metal lid, 7 rectifier plate, 8 heat insulating cover.

Claims

1. a module substrate; an electronic component mounted on the module substrate; a metal cover provided on the module substrate so as to cover the electronic components; an opening extending through the metal cover; a rectifying plate for guiding the flow of outside air passing through the opening so as not to directly hit the electronic components; A semiconductor module comprising:

2. The rectifying plate guides the flow of the outside air toward the inner surface of the metal lid. The semiconductor module according to claim 1 .

3. The installation angle of the rectifying plate is variable.

3. The semiconductor module according to claim 1.

4. A slit is formed in the rectifying plate.

3. The semiconductor module according to claim 1.

5. A plurality of the rectifying plates are arranged in a row in one of the openings.

3. The semiconductor module according to claim 1.

6. Further provided is a heat insulating cover that covers the outer surface of the metal lid and has a lower thermal conductivity than the metal lid.

3. The semiconductor module according to claim 1.

7. The heat insulating cover and the rectifying plate are integrally formed. The semiconductor module according to claim 6 .

8. The electronic components include a positioning semiconductor and a temperature compensated crystal oscillator.

3. The semiconductor module according to claim 1.

Images