High frequency module for radar sensor

Abstract

A high-frequency module for a radar sensor comprising: a high-frequency component in the form of a package (16) including a semiconductor chip and having a connection portion (18) on a surface for contacting the semiconductor chip; a system board (10) having a conductor path for driving and controlling the package (16); and a waveguide structure (24) for transmitting a microwave signal to or from the package (16), characterized in that the package (16) is disposed on an adapter card (20a), the adapter card (20a) is disposed on the system board (10), the package (16) is connected to the conductor path of the system board, and the adapter card (20a) constitutes a microwave waveguide structure (26) directly coupled to the waveguide structure (24).

Description

[Technical Field]

[0001] The present invention relates to a high-frequency module for a radar sensor that includes a packaged high-frequency component that includes a semiconductor chip and has a connection portion on its surface for contacting the semiconductor chip, a system board that has conductor paths for driving and controlling the package, and a waveguide structure for transmitting microwave signals to or from the package.

[0002] In particular, the present invention relates to a high frequency module for a radar sensor in an automobile. [Background technology]

[0003] Conventionally, radar sensors installed in automobiles often have a microwave waveguide structure formed using striplines on a substrate suitable for high frequencies, with high-frequency component packages mounted on the surface of the substrate. However, microwave waveguide structures with a waveguide shape that enables low-loss transmission of microwave power are also increasingly being used. Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to create a radio frequency module that can be manufactured cost-effectively and allows low-loss transmission of microwave power. [Means for solving the problem]

[0005] This problem is solved according to the present invention by forming a microwave waveguide structure in which the package is disposed on an adapter card, the adapter card is disposed on a system board, the package connects to conductor tracks on the system board, and the adapter card is directly coupled to the waveguide structure. [Effects of the Invention]

[0006] In the RF module of the present invention, only the adapter card needs to be made of RF compatible material; the system board does not need to be RF compatible. This allows for cost-effective manufacturing of the module. The package can be commercially available and mounted to the adapter card using known mounting and contacting techniques, just as a package is conventionally mounted to a system board. A microwave waveguide structure integrated into the adapter card allows for low-loss coupling to the package's waveguide structure.

[0007] Advantageous embodiments are set forth in the dependent claims. The microwave waveguide structures in the adapter card may be formed by stripline or waveguide structures. If the adapter card has waveguide structures, these may be implemented using, for example, SiW (Substrate-integrated Waveguide) technology.

[0008] The package may be, for example, an embedded wafer-level ball grid array (eWLB) package or a wafer-level packaging (WLP) module.

[0009] The embodiments will be described in more detail below with reference to the drawings. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view of a high-frequency module according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a waveguide structure in an adapter card. [Figure 3] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 4] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 5] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 6] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 7] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 8] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. [Figure 9] FIG. 10 is a schematic cross-sectional view of a high-frequency module according to a further embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] FIG. 1 shows a schematic cross-sectional view of a radio frequency module according to the present invention. The module includes a system board 10 formed in a known manner by successively alternating conductive and non-conductive layers, although the non-conductive layers need not be made of a radio frequency compatible material. In the illustrated example, the system board 10 has electronic modules 12, plug contacts 14, and the like mounted on both sides. On the side forming the top surface of the system board 10 in FIG. 1, radio frequency components are arranged in the form of packages 16, e.g., eWLB packages, with electrical connections formed by a grid of solder balls 18. However, unlike conventional radio frequency modules, the packages 16 are not mounted directly on the top surface of the system board 10 but are instead mounted on an adapter card 20a, which is in turn mounted on the top surface of the system board 10.

[0012] Each conductive layer of system board 10 forms a large number of conductor paths that are connected to conductor paths on other layers by through-holes, forming a network connecting electronic modules 12 and plug contacts 14 to each other and to adapter card 20a. Like system board 10, adapter card 20a also has a series of alternating conductive and non-conductive layers that form a network of conductor paths connected by through-holes, through which solder balls 18 on package 16 are electrically connected to contacts 22 on the underside of the adapter card, and through which contacts 22 are connected to conductor paths on system board 10.

[0013] The package 16 houses a semiconductor chip, such as an MMIC chip (Monolithic Microwave Integrated Circuit), used to generate and / or process microwave signals.

[0014] 1, a waveguide structure 24 is disposed on the top surface of system board 10 adjacent adapter card 20a and one end of package 16, and this waveguide structure 24 may itself form an antenna arrangement or may be used to route microwave signals generated within package 16 to one or more antennas and / or signals received by the antennas to the MMIC chip. Adapter card 20 is made of a high frequency compatible material and has a microwave waveguide structure 26 therein through which the MMIC chip is coupled to waveguide structure 24.

[0015] 1, package 16 has coupling points 28 for electromagnetically radiatively coupling the MMIC to one end of a waveguide structure 26. At the opposite end, microwave waveguide structure 26 defines a window 30 that opens upward into waveguide structure 24, allowing microwave signals to enter and exit waveguide structure 24. Because numerous embodiments of the configuration of waveguide structure 24 are known, the details of the waveguide structure will not be shown or described in detail herein.

[0016] The microwave waveguide structure 26 may be, for example, a waveguide structure in SiW technology. A typical configuration of such a waveguide structure 26 is shown in FIG. 2. One of the conductive layers of the adapter card 20a forms a rectangular, conductive lower end face 32 of the waveguide structure, which here forms the microwave waveguide structure 26. The space above this end face 32 is "fenced" by through holes 34. The distance between adjacent through holes 34 is smaller than the wavelength of the transmitted microwaves, so that the through holes 34 together act like conductive walls of the waveguide. The conductive layer on the top surface of the adapter card 20a forms the upper end face 36 of the waveguide structure. The upper end face 36 also has a rectangular contour, but is shorter than the lower end face 32, so that at the opposite ends of the waveguide, the aforementioned window 30 for coupling to the waveguide structure 24 is formed on the one hand, and a further window 38 is formed on the other hand, facing the coupling point 28 (FIG. 1). It is understood that in the space enclosed by through-hole 34, all conductive layers of adapter card 20 between termination faces 32, 36 have been removed or eliminated so as not to impede microwave propagation.

[0017] FIG. 3 shows a further embodiment of a radio frequency module with an adapter card 20b, which differs from the adapter card 20a according to FIG. 1 in that the window 30 for coupling to the waveguide module 24 is not on the top surface of the adapter card, but on an end surface of the adapter card.

[0018] FIG. 4 shows an embodiment in which the waveguide structure 24c is located on the underside of a system board 10c. The system board 10c differs from the previously described system board 10 in that it has a single opening 40 extending from the top to the bottom, uninterrupted by a conductive layer. In this embodiment, an adapter card 20c is used, which differs from the previously described adapter card in that the window 30 opens downward, toward the opening 40. In this case, the microwave waveguide structure 26 has an L-shaped configuration, with a horizontal branch extending from the coupling point 28 to the opening location and a vertical branch connecting the horizontal branch to the opening 40. The microwave waveguide structure 26, in this example, may be a SiW technology waveguide structure. The opening 40 may be an air-filled hole or cutout in the substrate, or may optionally be filled with a dielectric. The vertical walls of the opening 40 may be optionally metallized, fenced with through-holes, or formed by metallized plug-ins.

[0019] Figure 5 shows an embodiment in which adapter card 20d replaces adapter card 20a shown in Figure 1. The difference is that microwave waveguide structure 26 has a stripline 42 instead of a waveguide structure. In this case, the microwave signal is output from the MMIC by galvanic coupling between stripline 42 and one or more solder balls 18 of package 16. Window 30 in Figure 6 has been replaced by a patch 44, which inputs the signal transmitted via stripline 42 into waveguide structure 24.

[0020] The striplines 42 may optionally be introduced on top of or within the circuit board 20d and may be configured in any known manner, for example as shielded or unshielded microstriplines, as "tri-plate" lines, as "suspended substrate" lines, as microstriplines with ground slots, as multiple coupled microstriplines, as coplanar striplines, as coplanar lines, as slotlines or shielded slotlines or finlines.

[0021] Figure 6 shows an embodiment combining the waveguide structure 24c shown in Figure 4 with a system board 10c having an adapter card 20e, in which the microwave waveguide structure 26 has a stripline 42 and a patch 44 similar to those in Figure 5. However, here the underside of the adapter card has an additional patch 46 which, together with the patch 44, forms a resonator for outputting microwave power into the aperture 40. In the space between the two patches 44, 46 of the adapter card 20, all conductive layers have been removed or eliminated, forming an uninterrupted resonant cavity.

[0022] For the opening 40, all configurations described above in relation to FIG. 4 are also contemplated in this embodiment. FIG. 7 shows an embodiment that differs from that according to FIG. 6 in that instead of adapter card 20e, an adapter card 20f is provided that has a coaxial line 48 instead of a resonator to transmit microwave signals between stripline 42 and patch 46.

[0023] FIG. 8 shows an embodiment which differs from that according to FIG. 7 in that instead of the coaxial line 48, an adapter card 20g is provided which has a waveguide structure 50, for example a SiW-SiW waveguide junction, which is constructed according to the principle shown in FIG. 2.

[0024] FIG. 9 shows an embodiment which differs from the embodiment according to FIG. 3 in that the adapter card 20a is replaced by an adapter card 20h, in which the microwave waveguide structure 26 comprises a stripline 42 galvanically coupled to one of the solder balls 18 and a waveguide structure 52 (SiW-SiW waveguide junction) which forms an upwardly opening window for coupling to the waveguide structure 24.

Claims

1. A high-frequency module for a radar sensor includes a high-frequency component in the form of a package (16) including a semiconductor chip and having a connection portion on a surface for contacting the semiconductor chip, a system board (10) having a conductor path for driving and controlling the package (16), and a waveguide structure (24) for transmitting a microwave signal to or from the package (16), wherein the package (16) is disposed on an adapter card, the adapter card is disposed on the system board (10), the package (16) is connected to the conductor path of the system board, and the adapter card forms a microwave waveguide structure (26) directly coupled to the waveguide structure (24), The waveguide structure (24) is disposed on the same side of the system board (10) as the adapter card.

2. A high-frequency module as described in claim 1, wherein the waveguide structure (24) forms an antenna arrangement configuration.

3. The radio frequency module of claim 1 , wherein the microwave waveguide structure (26) comprises a waveguide structure (52).

4. 4. The radio frequency module of claim 3, wherein the waveguide structure (52) of the adapter card is implemented using SiW technology.

5. 2. The high frequency module according to claim 1, wherein the microwave waveguide structure (26) comprises a stripline (42) instead of a waveguide structure.

6. 6. The radio frequency module of claim 5, wherein the stripline (42) is coupled to the waveguide structure (24) through a patch (44).

7. The radio frequency module of claim 1, wherein the package (16) is galvanically coupled to the microwave waveguide structure (26).

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