Ultra-wideband interface for integrated circuits

Abstract

An external port (100) for bidirectional transmission of radio frequency (RF) signals for an integrated circuit (IC) package, where the IC package (1000) comprises a housing (1010) having an access wall (1020) and an IC chip (1030) established on a first substrate (1040) contained in the housing (1010), the external port (100) comprising a dielectric waveguide structure (IC DRW 1) embeddable in the access wall (1020) of the housing, the dielectric waveguide structure (IC DRW 1) is configured for bidirectional transmission of RF signals.

Description

[0001] manual

[0002] This invention relates to an external port for bidirectional ultrawideband transmission of radio frequency (RF) signals in integrated circuit (IC) packages. Background Technology

[0003] Over the past few years, solid-state semiconductor devices have pushed their frequency limits to higher frequencies, and their adoption in various terahertz (THz) applications, such as communications, instrumentation, imaging, and sensing, is steadily increasing. Since proper packaging is crucial for improving the stability and reliability of integrated circuits (ICs), several packaging strategies have been investigated. With increasing frequencies, interconnecting ICs becomes challenging due to the impact of losses and manufacturing tolerances on signal integrity.

[0004] For ICs operating at frequencies below 30 GHz, the use of plastic molding packages is proven. Interconnects are then made via beam leads or balls (typically in a ground-signal-ground configuration), creating coplanar waveguides (CPWs). Internally, the IC chip is interconnected to pads via wire bonding or band bonding. However, as the frequency increases, parasitic series inductance becomes significant, making it impossible to use this technique for millimeter-wave and submillimeter-wave frequencies. The use of other techniques, such as low-temperature co-fired ceramic (LTCC) and multiple wire bonds per connection, can partially mitigate the losses, but practical limitations still exist for submillimeter-wave frequencies.

[0005] Other waveguides can be used for interconnection, but for frequencies above 100 GHz, they become either impractical in terms of size (like coaxial cables) or unsuitable for integration into IC packages (like rectangular waveguides). Chip-to-chip communication using integrated antennas has also been proposed. While this solution can be easily fitted into standard plastic packages, it is frequency-limited by the chosen antenna topology.

[0006] Our current method is as follows Figure 1 As shown, a single-mode excited dielectric waveguide enables low-loss, high-frequency, ultra-wideband signal interconnection. The rod is truncated and established as a bidirectional high-frequency port within the IC package wall. It can be used to connect to external dielectric waveguides, antennas, or another IC.

[0007] This invention overcomes the above-mentioned limitations and disadvantages. Summary of the Invention

[0008] This invention provides a solution for bidirectional ultra-wideband transmission of radio frequency (RF) signals in integrated circuit (IC) packages. It is compatible with several integrated circuit package types.

[0009] Therefore, the present invention relates to an external port comprising at least a waveguide port for bidirectional transmission of radio frequency (RF) signals within an integrated circuit (IC) package. Any signal coupled to the external port can be efficiently coupled to another dielectric structure, waveguide, antenna, or resonator, and thus can be used to implement telecommunications devices and high-frequency sensors. The dielectric waveguide structure can be used for radiation or reception through the proposed IC port.

[0010] The present invention has the following improvements:

[0011] External ports are novel ultra-wideband signal ports that can be integrated into existing IC packages. Depending on the device configuration, many external ports can be adapted into a single package.

[0012] External ports include dielectric waveguide structures (e.g., dielectric rod waveguides (DRWs)) integrated into the IC package. The dielectric waveguide structure can be fabricated from a high-dielectric-constant substrate (such as silicon, gallium arsenide (GaAs), or indium phosphide (InP)). On the outer side, the dielectric waveguide structure can be flat. On the inner side, the dielectric waveguide structure can be connected to the IC chip.

[0013] External ports can have a lower cutoff frequency depending on the port cross-sectional size; for example, a width of 1 mm results in a cutoff frequency of approximately 65 GHz.

[0014] External ports can have a higher cutoff frequency of at least 100 GHz, depending on manufacturing tolerances, thus allowing for a trade-off between manufacturing cost and bandwidth.

[0015] By using additional metal pins, the external port can extend the frequency range to lower frequencies (down to DC).

[0016] Therefore, a first aspect of the present invention relates to an external port for bidirectional transmission of radio frequency (RF) signals in an integrated circuit (IC) package, wherein the IC package includes a housing having an access wall and an IC chip built on a first substrate contained in the housing, and the external port includes a dielectric waveguide structure that can be embedded in the access wall of the housing, the dielectric waveguide structure being configured for bidirectional transmission of RF signals.

[0017] In the example, the dielectric waveguide structure operates as an ultra-wideband dielectric IC port and is configured to connect to a second IC chip, an external waveguide, a dielectric structure, or an antenna.

[0018] In the example, the dielectric waveguide structure provides a high-pass interconnect that operates in a high-frequency range, starting from a low cutoff frequency f0 in the microwave or millimeter-wave range and continuing up to a higher cutoff frequency of at least 100 GHz.

[0019] In another example, the external port also includes a second substrate and a first metallization layer. The second substrate is connected to a dielectric waveguide structure and can be connected to the first substrate. The first metallization layer can be connected to an IC chip and is built on the second substrate. The second substrate includes an RF substrate (such as quartz, laminate, ceramic, or silicon).

[0020] In a preferred example, the dielectric waveguide structure includes a tapered end.

[0021] In this example, the external port includes a second metallization layer electrically connected to the first metallization layer. In this example, the first and second metallization layers are metallic waveguide structures providing low-pass interconnects with a high cutoff frequency fo ranging from DC to millimeter waves. CH It operates within a low-frequency range. Furthermore, the external port may include a first electrical interconnect configured to electrically connect a first metallization layer and a second metallization layer.

[0022] In one example, the first electrical interconnect includes epoxy resin.

[0023] In one example, the external port also includes two metal pins that can be embedded in the access wall and connected to the IC chip via metal interconnects. The metal interconnects may include wire bonding, epoxy bonding, or band bonding.

[0024] In one example, the external port also includes a second electrical interconnect configured to electrically connect two metal pins to a second metallization layer.

[0025] Another aspect of the present invention relates to an IC package for transmitting or receiving RF signals, the IC package including an external port according to a first aspect of the present invention.

[0026] In one example, the first substrate of the IC package includes an RF substrate (such as quartz, laminate, and ceramic or silicon).

[0027] In one example, the access wall of the IC package includes a dovetail or V-groove shape, which serves as a mechanical aid for aligning external waveguides, antennas, connectors, or any other components or devices connected to the IC package port. Attached Figure Description

[0028] To better understand the above explanation and for illustrative purposes only, some non-limiting drawings are included, which schematically depict actual embodiments.

[0029] Figure 1 and Figure 2 A first example of an external port according to the present invention is shown.

[0030] Figure 3 and Figure 4 A second example of an external port according to the invention is shown, wherein the dielectric waveguide structure has a tapered end.

[0031] Figure 5 A third example of an external port according to the invention is shown, which includes metal pins and a metallization layer.

[0032] Figure 6 and Figure 7 A fourth example of an external port according to the invention is shown, which includes two metallization layers.

[0033] Figure 8 A fifth example of an external port according to the invention is shown, which includes metal pins and electrical connections.

[0034] Figure 9 and Figure 10 An example of an IC package with mechanical aids in the access wall is shown. Detailed Implementation

[0035] Figure 1 A first example of an external port (100) for bidirectional transmission of radio frequency (RF) signals for an integrated circuit (IC) package is shown, wherein the IC package (1000) includes a housing (1010) having an access wall (1020). The external port (100) includes a dielectric waveguide structure (IC DRW 1) embedded in the access wall (1020) of the housing (1010), which is configured for bidirectional transmission of RF signals.

[0036] In this specific example, an 8-lead TDFN plastic IC package (1000) is shown as an example. The access wall (1020) in the housing (1010) has been reserved for a dielectric waveguide structure (IC DRW 1). The metal pins of the housing (1010) are available for conventional electrical connections.

[0037] A dielectric rod waveguide with a dielectric constant similar to or equal to that of the dielectric waveguide structure (IC DRW 1) can be attached to the access wall (1020). The dielectric waveguide structure (IC DRW 1) serves as an ultra-wideband dielectric IC port and can be used to connect an IC package (1000) to another ultra-wideband IC port, to an external waveguide (i.e., a rectangular waveguide), a dielectric structure (i.e., a resonator), or an antenna.

[0038] Figure 2 It shows Figure 1An internal view of an example. The IC package (1000) includes an IC chip (1030) built on a substrate (1040) contained within a housing (1010). The IC package (1000) is soldered into any substrate (1040) with a low or medium dielectric constant (such as FR-4, Rogers, Duroid). The first substrate (1040) includes an RF substrate (such as quartz, laminate, and ceramic or silicon).

[0039] The dielectric waveguide structure (IC DRW 1) connects the IC chip (1030) to the access wall (1020) for bidirectional transmission of RF signals and provides a high-pass interconnect that operates over a high frequency range, starting from a low cutoff frequency f0 in the microwave or millimeter-wave range and continuing up to a higher cutoff frequency of at least 100 GHz.

[0040] Figure 3 An internal view of a second example of an external port (100) according to the invention is shown, wherein a dielectric waveguide structure (IC DRW 1) is included. The tapered tip of the dielectric waveguide structure (IC DRW 1) is located on top of the IC chip (1030).

[0041] exist Figure 3 In the example, the external port (100) also includes a second substrate (110) and a first metallization layer (120A). The second substrate (110) is connected to a dielectric waveguide structure (IC DRW 1) and to a first substrate (1040) of an IC chip (1030). The first metallization layer (120A) is connected to the IC chip (1030) and is established on the substrate (1040). The second substrate (110) includes an RF substrate (such as quartz, laminate, ceramic, or silicon). The first metallization layer (120A) may be a (tapered) metal waveguide structure providing low-pass interconnects with a high cutoff frequency fo ranging from DC to millimeter waves. CH It operates within a low-frequency range.

[0042] Figure 4 It shows Figure 3 A detailed view of the example. Without inter-mode interference, the dielectric waveguide structure (IC DRW1) propagates RF signals with low loss and no transmission zeros over a wide bandwidth. Therefore, most of the signal power must be coupled to the waveguide fundamental mode for all frequencies. The main bandwidth limitation comes from the presence of higher-order modes. Higher-order modes can be excited due to misalignment between components, so fabrication capability will determine the highest frequency. To extend the high-frequency limit, a first metallization layer (120A) (e.g., a tapered metal waveguide structure) can be printed into the IC chip (1030).

[0043] The cross-sectional dimension of the horizontal dielectric waveguide structure (IC DRW 1) is the width of (IC DRW 1), and the vertical dimension of the horizontal dielectric waveguide structure (IC DRW 1) is the thickness of (IC DRW 1). Both are related to the low-frequency limitation of the external port (100).

[0044] Figure 5 A third example of an external port according to the invention is shown, comprising two metal pins (150) and a first metallization layer (120A) providing DC extension. In the third example, the external port (100) further includes two metal pins (150) that can be embedded in an access wall (1020) and connected to an IC chip (1030) via a metal connection device (150A) connecting the two metal pins (150) to the first metallization layer (120A). The metal connection device (150A) includes wire bonding for this particular case. In other examples, the metal connection device (150A) may comprise epoxy resin or band bonding.

[0045] Figure 6 A fourth example of an external port (100) according to the invention is shown, which includes two metallization layers. Specifically, in this fourth example, the external port (100) includes a first metallization layer (120A) and a second metallization layer (120B) electrically connected to the first metallization layer (120A). The first metallization layer (120A) and the second metallization layer (120B) may be (tapered) metallic waveguide structures providing low-pass interconnects with high cutoff frequencies f from DC to millimeter waves. CH It operates within a low-frequency range.

[0046] In this example, to achieve a bandwidth from 65 GHz to 300 GHz, the length of the second metallization layer (120B) is 14.5 mm. To avoid this increase in length, the second metallization layer (120B) can be extended to the outside of the IC chip (1030).

[0047] A fourth example of the external port (100) also includes a first electrical interconnect (140A) configured to electrically connect a first metallization layer (120A) and a second metallization layer (120B). The first metallization layer (120A) is connected to the second metallization layer (120B) by means of the first electrical interconnect (140A), which may include a conductive epoxy resin or the like. The quality of this electrical contact (at its highest frequency f) m In other words, f is linearly dependent on the cutoff point. A cutoff point closer to the external port (100) results in f m Approaching f0. For f mAt the above frequencies, the signal is coupled to the dielectric waveguide structure (IC DRW 1) before the transition between the IC chip (1030) and the second metallization layer (120B).

[0048] Figure 7 It shows Figure 6 Detailed view. In this figure, a first electrical interconnect (140A) configured to electrically connect a first metallization layer (120A) and a second metallization layer (120B) and a second substrate (110) connected to a dielectric waveguide structure (IC DRW1) and connected to a first substrate (1040) are shown in detail.

[0049] Figure 8 A fifth example of an external port (100) according to the invention is shown, comprising two metal pins (150) and an electrical interconnect. The external port (100) includes two metal pins (150) that can be embedded in an access wall (1020) and connected to an IC chip (1030) via a metal connection device (150A), and a second electrical interconnect (140B) configured to electrically connect the two metal pins (150) to a second metallization layer (120B) providing DC extension. The DC extension is internally achieved by connecting the two metal pins (150) to the second metallization layer (120B) (e.g., a tapered metal waveguide structure).

[0050] As described above, the bandwidth can be extended to lower frequencies by adding two metal pins (150) to the external port (100). Therefore, the external port (100) comprises a dielectric waveguide structure (IC DRW 1) and two metal pins (150). In this example, the external port (100) is hybrid because it comprises a dielectric waveguide structure (IC DRW 1) and two metal pins (150). For lower frequencies, it operates as a balanced bi-wire. For frequencies above f0, the signal is coupled to HE. 11 In mode.

[0051] Figure 9 and Figure 10 An example of an IC package (1000) with mechanical aids in the access wall (1020) is shown. In the previous example, it was assumed that the access wall (1020) was a flat surface. Mechanical aids can also be added to the access wall 1020 to enhance the alignment between the external waveguide and the external port 100.

[0052] exist Figure 9 and Figure 10In this context, the access wall (1020) can be either dovetail-shaped or V-groove-shaped to accommodate an external waveguide (not part of this invention) having a cap made of any material with a dielectric constant lower than that of the DRW (i.e., plastic or epoxy resin) that matches the shape of the IC port, since molding may be easier if it is not directly molded in the DRW.

Claims

1. An external port (100) for bidirectional transmission of radio frequency (RF) signals in an integrated circuit (IC) package, wherein, The IC package (1000) includes a housing (1010) having an access wall (1020) and an IC chip (1030) disposed on a first substrate (1040) contained within the housing (1010). The external port (100) includes: A dielectric waveguide structure (IC DRW 1) is available for embedding in the access wall (1020) of the housing and is configured for bidirectional transmission of RF signals.

2. The external port (100) according to claim 1, wherein, The dielectric waveguide structure (IC DRW 1) serves as an ultra-wideband dielectric IC port and is configured to connect to a second IC chip, an external waveguide, a dielectric structure, or an antenna.

3. The external port (100) according to claim 1 or 2, wherein, The dielectric waveguide structure (IC DRW 1) provides a high-pass interconnect that operates over a high frequency range, starting from a low cutoff frequency f0 in the microwave or millimeter-wave range and continuing up to a higher cutoff frequency of at least 100 GHz.

4. The external port (100) according to claims 1 to 3 further includes: A second substrate (110) is connected to the dielectric waveguide structure (IC DRW 1) and can be connected to the first substrate (1040); and A first metallization layer (120A) is connected to the IC chip (1030) and is established on the substrate (1040).

5. The external port according to the preceding claim, wherein, The second substrate (110) includes an RF substrate, such as quartz, laminate, ceramic, or silicon.

6. The external port according to the preceding claim, wherein, The dielectric waveguide structure (IC DRW 1) includes a tapered end.

7. The external port according to claims 4 to 6, further comprising: A second metallization layer (120B) is electrically connected to the first metallization layer (120A) and mechanically connected to the dielectric waveguide structure (IC DRW 1).

8. The external port according to claim 7, wherein, The first metallization layer (120A) and the second metallization layer (120B) are metal waveguide structures that provide low-pass interconnects, the metal waveguide structures having a high cutoff frequency f in the range from DC to the millimeter wave. CH It operates within a low-frequency range.

9. The external port (100) according to the preceding claim further includes: A first electrical interconnect (140A) is configured to electrically connect the first metallization layer (120A) and the second metallization layer (120B).

10. The external port (100) according to the preceding claim, wherein, The first electrical interconnect (140A) includes conductive epoxy resin, wire bonding, or band bonding.

11. The external port (100) according to any one of the preceding claims further includes: Two metal pins (150) are embedded in the access wall (1020) and can be connected to the IC chip (1030) via a metal connector (150A).

12. The external port (100) according to the preceding claim, wherein, The metal connection device (150A) includes wire bonding, epoxy resin, or band bonding.

13. The external port (100) according to claim 11 or 12 further includes a second electrical interconnect (140B) configured to electrically connect the two metal pins (150) to the second metallization layer (120B).

14. An integrated circuit IC package (1000) for transmitting or receiving RF signals, the IC package (1000) including an external port according to claims 1 to 13.

15. The IC package according to claim 14, wherein, The first substrate (1040) includes an RF substrate, such as quartz, laminate, ceramic, or silicon.

16. The IC package (1000) according to claim 14 or 15, wherein, The access wall (1020) includes a dovetail shape or a V-shaped groove.

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