Terahertz chip packaging module

Abstract

The present application provides a terahertz chip packaging module. The module comprises a metal housing, a metal coplanar waveguide, and a terahertz chip, a first chamber and a second chamber which are connected in a bending manner are formed in the metal housing, a first interface is formed at one end of the first chamber, and a second interface is formed at one end of the second chamber; the metal coplanar waveguide passes through the second chamber, and two ends of the metal coplanar waveguide are respectively connected to the first chamber and the second interface; the terahertz chip is arranged on the metal coplanar waveguide, and the metal coplanar waveguide comprises a signal electrode and two ground electrodes which are arranged side by side in the width direction of the second chamber; a first tapered area is formed at the end of the metal coplanar waveguide facing the first chamber; the width of the signal electrode is gradually increased from the first tapered area to the first chamber, and the widths of the two ground electrodes are gradually reduced from the first tapered area to the first chamber.

Description

Terahertz chip packaging module

[0001] This application claims priority to Chinese patent application No. 202410403169.5 filed on April 3, 2024, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of waveguide-type terahertz chips, and in particular to a terahertz chip packaging module. Background Art

[0003] In related technologies, terahertz chip modules based on metal rectangular cavity waveguide packaging can be easily connected to other standard terahertz modules, often coupling terahertz signals through a silicon hyperhemispherical lens and a terahertz-metal rectangular cavity waveguide conversion structure. However, this setup suffers from low signal coupling efficiency due to the significant mismatch between the terahertz propagation modes of the silicon hyperhemispherical lens and the metal rectangular cavity waveguide. Technical issues

[0004] The main purpose of this application is to provide a terahertz chip packaging module, aiming to improve the signal coupling efficiency of the terahertz chip. Technical Solutions

[0005] To achieve the above objectives, the present application proposes a terahertz chip packaging module, which includes:

[0006] A metal shell having a first cavity and a second cavity connected by a bend formed therein, wherein an end of the first cavity facing away from the second cavity forms a first interface for inputting and outputting terahertz signals, and an end of the second cavity facing away from the first cavity forms a second interface for inputting and outputting microwave signals;

[0007] a metal coplanar waveguide, the metal coplanar waveguide being arranged in the second cavity, with two ends of the metal coplanar waveguide being respectively connected to the first cavity and the second interface, for transmitting the terahertz signal and the microwave signal; and

[0008] a terahertz chip, the terahertz chip being disposed in the metal coplanar waveguide and being used for coupling the terahertz signal and the microwave signal;

[0009] The metal coplanar waveguide includes a signal electrode and two ground electrodes arranged side by side along the width direction of the second cavity, and the two ground electrodes are respectively arranged on both sides of the signal electrode at intervals;

[0010] A first gradient region is formed at one end of the metal coplanar waveguide toward the first cavity. The width of the signal electrode gradually increases in the first gradient region toward the first cavity, and the width of the two ground electrodes gradually decreases in the first gradient region toward the first cavity.

[0011] In one embodiment, the metal coplanar waveguide comprises:

[0012] a main body, the main body being disposed in the second chamber and connected to the terahertz chip;

[0013] a first connecting portion, the first connecting portion being provided at one end of the main body portion facing the first chamber and extending from the main body portion into the first chamber, for coupling the terahertz signal in the first chamber; and

[0014] a second connecting portion, the second connecting portion being provided at one end of the main body facing the second cavity and exposed at the second interface, and being used for externally connecting to a microwave metal transmission line to couple the microwave signal;

[0015] The first gradual change area is formed at one end of the main body facing the first connecting portion.

[0016] In one embodiment, a second gradient region is formed on one end of the second connecting portion facing the main body;

[0017] The width of the signal electrode is gradually increased from the second gradient region toward the second interface, and the width of the two ground electrodes is gradually decreased from the first gradient region toward the second interface.

[0018] In one embodiment, the second chamber includes a first cavity and a second cavity that are sequentially connected from top to bottom, and the width of the first cavity is smaller than that of the second cavity, so as to form a step surface between the first cavity and the second cavity;

[0019] The metal coplanar waveguide is arranged in the second cavity and forms an ohmic contact with the stepped surface.

[0020] In one embodiment, the first cavity includes a first connecting section located above the main body, and a width of the first connecting section is smaller than a width of the metal coplanar waveguide.

[0021] In one embodiment, the first cavity includes a second connecting segment located above the second connecting portion, and a width of the second connecting segment is not less than a width of the metal coplanar waveguide.

[0022] In one embodiment, the second chamber further includes a third cavity, which is formed below the main body and communicates with the second cavity;

[0023] The width of the third cavity is smaller than that of the second cavity.

[0024] In one embodiment, the first chamber includes a first segment and a second segment that are sequentially connected along its length, the first segment is bent and connected to the second chamber, and an end of the second segment facing away from the first segment forms the first interface;

[0025] The second segment is wider than the first segment.

[0026] In one embodiment, the second segment and the first segment are connected by a curved surface transition;

[0027] And / or, a reflective structure is formed on one end of the first segment away from the second segment, and a width of the reflective structure is gradually narrowed in a direction away from the first segment.

[0028] In one embodiment, the terahertz chip includes:

[0029] a terahertz negative resistance diode, provided in the metal coplanar waveguide, for coupling the terahertz signal and the microwave signal;

[0030] a low-pass filter structure, provided in the metal coplanar waveguide and located at an end of the terahertz negative resistance diode facing the second interface, for reflecting the terahertz signal and transmitting the microwave signal; and

[0031] The ballast resistor is provided in the metal coplanar waveguide and is located at an end of the low-pass filter structure away from the terahertz negative resistance diode. Beneficial effects

[0032] The technical solution of the present application is to form a first cavity and a second cavity connected by a bend in a metal shell, and form a metal rectangular cavity waveguide through the first cavity. The first interface at the first cavity is used to input and output terahertz signals; the second cavity is used to insert the metal coplanar waveguide and the terahertz chip. The metal coplanar waveguide can play the role of signal transmission. One end of the metal coplanar waveguide is connected to the second interface at the second cavity, thereby forming a metal electrode interface for inputting and outputting microwave signals, and the other end is connected to the first cavity for coupling terahertz signals. Thus, a terahertz path and a microwave path can be formed at both ends of the terahertz chip through the metal coplanar waveguide. Among them, the metal coplanar waveguide includes a signal electrode and two ground electrodes arranged side by side along the width direction of the second cavity. The two ground electrodes are respectively arranged on both sides of the signal electrode. A first gradient region is formed on one end of the metal coplanar waveguide facing the first cavity. The width of the signal electrode gradually increases in the first gradient region toward the first cavity, and the width of the two ground electrodes gradually decreases in the first gradient region toward the first cavity. With this arrangement, signal coupling on the terahertz path can be achieved through the first gradient region of the metal coplanar waveguide, and the metal coplanar waveguide structure in the first gradient region can reduce the leakage of the terahertz signal to its two ends, thereby achieving the effect of shielding the terahertz signal, thereby achieving better coupling characteristics and helping to improve the coupling efficiency of the terahertz chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0034] FIG1 is a structural diagram of an embodiment of a terahertz chip packaging module of the present application;

[0035] FIG2 is a top view of the terahertz chip packaging module in FIG1 ;

[0036] FIG3 is a first cross-sectional view of the terahertz chip packaging module in FIG1 ;

[0037] FIG4 is a second cross-sectional view of the terahertz chip packaging module in FIG1 ;

[0038] FIG5 is a third cross-sectional view of the terahertz chip packaging module in FIG1 ;

[0039] FIG6 is a schematic diagram of the terahertz coupling efficiency of the terahertz chip packaging module in FIG1 ;

[0040] FIG7 is a schematic diagram of the electric field distribution of the terahertz chip packaging module in FIG1 ;

[0041] FIG8 is a schematic diagram of the microwave coupling efficiency of the terahertz chip packaging module in FIG1 .

[0042] Description of Figure Numbers:

[0043] Reference numerals: Reference numerals: 100 terahertz chip packaging module 123 third cavity 10 metal housing 20 metal coplanar waveguide 11 first cavity 20a signal electrode 11a first interface 20b ground electrode 111 first segment 21 main body 111a reflective structure 211 first gradient region 112 second segment 22 first connecting portion 12 second cavity 23 second connecting portion 12a second interface 231 second gradient region 121 first cavity 30 terahertz chip 121a first connecting segment 31 terahertz negative resistance diode 121b second connecting segment 32 low-pass filter structure 122 second cavity 33 ballast resistor

[0044] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. Modes for Carrying Out the Invention

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0047] In this application, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0049] In the related art, terahertz chip packaging modules based on metal rectangular cavity waveguide packaging can be easily interconnected with other standard terahertz modules, and terahertz signal coupling is often achieved through a silicon super-hemispherical lens and a terahertz metal rectangular cavity waveguide conversion structure. However, in this setting, due to the natural large mismatch between the terahertz propagation modes of the silicon super-hemispherical lens and the metal rectangular cavity waveguide, it is necessary to increase the coupling efficiency by increasing the length of the metal cavity gradient structure, resulting in the terahertz chip packaging module having large packaging size and high cost. This makes the terahertz signal coupling efficiency of the terahertz chip packaging module low under the premise of limited packaging size. In addition, there are inevitable multiple terahertz reflections between the interface of the silicon super-hemispherical lens and the metal cavity gradient structure, which also leads to the problem of narrow 3dB bandwidth of the terahertz chip packaging module. Furthermore, in related art, the terahertz chip in a terahertz chip packaging module is typically coupled to a microwave SMA interface using gold wire bonding technology. To prevent the integration of metal transmission lines on a silicon hyperhemispherical lens from deteriorating the terahertz radiation characteristics of the lens, the electrodes of the metal transmission lines are positioned away from the center of the silicon hyperhemispherical lens and the positive and negative electrodes of the terahertz chip. This results in a longer gold wire bonding distance, which in turn limits the 3dB bandwidth of the microwave frequency band. Therefore, the present application proposes a terahertz chip packaging module 100 with high coupling efficiency and a large 3dB bandwidth.

[0050] 1 to 8 , in some embodiments of the terahertz chip packaging module 100 of the present invention, the terahertz chip packaging module 100 includes:

[0051] A metal housing 10 is provided with a first cavity 11 and a second cavity 12 connected by a folded connection. The end of the first cavity 11 facing away from the second cavity 12 forms a first interface 11a for inputting and outputting terahertz signals. The end of the second cavity 12 facing away from the first cavity 11 forms a second interface 12a for inputting and outputting microwave signals.

[0052] a metal coplanar waveguide 20, the metal coplanar waveguide 20 being provided through the second cavity 12, with two ends of the metal coplanar waveguide 20 respectively connected to the first cavity 11 and the second interface 12a, for transmitting the terahertz signal and the microwave signal; and

[0053] a terahertz chip 30 , the terahertz chip 30 being disposed in the metal coplanar waveguide 20 and configured to couple the terahertz signal and the microwave signal;

[0054] The metal coplanar waveguide 20 includes a signal electrode 20a and two ground electrodes 20b arranged side by side along the width direction of the second cavity 12, and the two ground electrodes 20b are spaced apart and arranged on both sides of the signal electrode 20a;

[0055] A first gradient region 211 is formed at one end of the metal coplanar waveguide 20 facing the first cavity 11. The width of the signal electrode 20a gradually increases in the first gradient region 211 toward the first cavity 11, and the width of the two ground electrodes 20b gradually decreases in the first gradient region 211 toward the first cavity 11.

[0056] The first chamber 11 is a metal rectangular cavity waveguide, and the first interface 11a is a metal rectangular cavity waveguide interface with the same dimensions as a standard metal rectangular cavity waveguide, used for inputting and outputting terahertz signals. The terahertz chip 30 includes, but is not limited to, a terahertz radiation source and a detector chip. The terahertz chip 30 is connected to the metal coplanar waveguide 20 to enable signal transmission through the metal coplanar waveguide 20. The terahertz chip packaging module 100 also includes a dielectric substrate inserted into the second chamber 12. The metal coplanar waveguide 20 is disposed on a side surface of the dielectric substrate and may be composed of a signal electrode 20a and two ground electrodes 20b arranged side by side on the upper surface of the dielectric substrate. A first gradient region 211 is formed at one end of the metal coplanar waveguide 20 facing the first cavity 11. The width dimensions of the electrodes in the metal coplanar waveguide 20 in the first gradient region 211 are gradually changed. The gradient function includes, but is not limited to, a linear function and an exponential function. In addition, the sum of the widths of the signal electrode 20a and the two ground electrodes 20b of the metal coplanar waveguide 20 is a constant value. That is, the metal coplanar waveguide 20 as a whole has a structure with a uniform width. This facilitates the processing and assembly of the metal coplanar waveguide 20.

[0057] In some embodiments, the first chamber 11 and the second chamber 12 are connected by a bend and are arranged perpendicular to each other. This allows the terahertz chip packaging module 100 to have better signal coupling efficiency. Of course, the technical solution of the present application is not limited to this. The first chamber 11 and the second chamber 12 can also be connected at other angles. The specific implementation method can be set according to actual needs and is not limited here.

[0058] 1 to 5 , in some embodiments of the terahertz chip packaging module 100 , the metal coplanar waveguide 20 includes:

[0059] a main body 21 , the main body 21 being disposed in the second chamber 12 and connected to the terahertz chip 30 ;

[0060] a first connecting portion 22 , which is provided at one end of the main body 21 facing the first chamber 11 and extends from the main body 21 into the first chamber 11 for coupling the terahertz signal in the first chamber 11 ; and

[0061] a second connecting portion 23 , which is provided at one end of the main body 21 facing the second chamber 12 and exposed at the second interface 12 a , and is used for connecting an external microwave metal transmission line to couple the microwave signal;

[0062] A first gradual transition area 211 is formed at one end of the main body 21 facing the first connecting portion 22 .

[0063] In this embodiment, the main body 21 is composed of a signal electrode 20a and two ground electrodes 20b arranged side by side. The first connecting portion 22 is composed of the signal electrode 20a and protrudes from the signal electrode 20a on the main body 21 into the first cavity 11 to form a microstrip waveguide probe. The second connecting portion 23 is composed of the signal electrode 20a and the two ground electrodes 20b arranged side by side to form a metal electrode interface at the second interface 12a for external connection to a microwave metal transmission line. It should be noted that to ensure the coupling efficiency of the terahertz signal, the length of the microstrip waveguide probe extending into the first cavity 11 can be set to approximately half the width of the first cavity 11. On this basis, the width of the first cavity 11 can be smaller. In this way, the length of the microstrip waveguide probe can be correspondingly reduced, thereby reducing the metal loss of the metal coplanar waveguide 20 and improving the signal coupling efficiency between the terahertz chip 30 and the first cavity 11.

[0064] 1 to 5 , in some embodiments of the terahertz chip packaging module 100 of the present invention, a second gradient region 231 is formed on one end of the second connection portion 23 facing the main body portion 21 ;

[0065] The width of the signal electrode 20a is gradually increased in the second gradual transition region 231 toward the second interface 12a, and the width of the two ground electrodes 20b is gradually decreased in the first gradual transition region 211 toward the second interface 12a.

[0066] The widths of the electrodes in the metal coplanar waveguide 20 in the second gradient region 231 are gradually varied, with the gradient function including, but not limited to, linear and exponential functions. By gradually increasing the width of the signal electrode 20a in the second gradient region 231 toward the second interface 12a, and gradually decreasing the widths of the two ground electrodes 20b in the first gradient region 211 toward the second interface 12a, the sum of the widths of the signal electrode 20a and the two ground electrodes 20b in the metal coplanar waveguide 20 can be made constant, i.e., the metal coplanar waveguide 20 as a whole has a uniform width. This facilitates the processing and assembly of the metal coplanar waveguide 20. Furthermore, by locating the metal coplanar waveguide 20 in the second gradient region 231 within the second cavity 12, the leakage of microwave signals to the ground electrodes 20b at both ends can be reduced, thereby achieving a microwave shielding effect, thereby achieving better coupling characteristics, and resolving the problem of low coupling efficiency caused by impedance mismatch.

[0067] Referring to Figures 1 to 5, in some embodiments of the terahertz chip packaging module 100 of the present invention, the second chamber 12 includes a first cavity 121 and a second connecting section 122 of the second cavity 121b that are sequentially connected from top to bottom, and the width of the first cavity 121 is smaller than the second connecting section 122 of the second cavity 121b, so as to form a step surface between the first cavity 121 and the second connecting section 122 of the second cavity 121b;

[0068] The metal coplanar waveguide 20 is provided in the second connecting section 122 of the second cavity 121b and forms an ohmic contact with the stepped surface.

[0069] Such a configuration enables at least part of the metal area of ​​the two ground electrodes 20b of the metal coplanar waveguide 20 in the first gradient region 211 to form ohmic contact with the metal step surface of the second connecting section 122 of the second cavity 121b, thereby reducing the leakage of the terahertz signal toward the metal ground electrodes 20b at both ends, achieving the effect of shielding the terahertz signal, and thus realizing better coupling characteristics.

[0070] Specifically, referring to Figures 3 and 4, in some embodiments of the inventive terahertz chip packaging module 100, the first cavity 121 includes a first connecting segment 121a located above the main body 21, and the width of the first connecting segment 121a is smaller than the width of the metal coplanar waveguide 20.

[0071] In this embodiment, the metal coplanar waveguide 20 includes a signal electrode 20a and two ground electrodes 20b disposed on either side of the signal electrode 20a. The width of the first cavity 121 is smaller than that of the metal coplanar waveguide 20, the width of the second connecting section 122 of the second cavity 121b matches the width of the metal coplanar waveguide 20, and the first cavity 121 is centered relative to the second connecting section 122 of the second cavity 121b. Thus, two stepped surfaces are formed on either side of the first cavity 121, each of which can be used to form an ohmic contact with a ground electrode 20b. The ohmic contact between the ground electrode 20b and the stepped surface can be formed directly or by using a process including, but not limited to, metal conductive adhesive. The specific implementation method can be customized according to actual needs and is not limited here.

[0072] 5 , in some embodiments of the terahertz chip packaging module 100 , the first cavity 121 includes a second connecting segment located above the second connecting portion 23 , and a width of the second connecting segment is not less than a width of the metal coplanar waveguide 20 .

[0073] In this embodiment, the second connection section 23 of the metal coplanar waveguide 20 is composed of a signal electrode 20a and two ground electrodes 20b arranged side by side, forming a metal electrode interface at the second interface 12a for connecting to an external microwave metal transmission line. The signal electrode 20a and the two ground electrodes 20b are arranged with equal width. Since the metal electrode interface and the microwave circuit are typically interconnected using a gold wire bonding process, setting the width of the second connection section to be no less than the width of the metal coplanar waveguide 20 can prevent the electrodes of the metal coplanar waveguide 20 from connecting to the metal cavity wall of the second cavity 12. This allows the electrodes of the metal coplanar waveguide 20 to have a larger metal area, facilitating connection to an external module via a gold wire bonding process.

[0074] Referring to FIG. 3 , in some embodiments of the terahertz chip packaging module 100 , the second chamber 12 further includes a third cavity 123 , which is formed below the main body 21 and communicates with the second connecting section 122 of the second cavity 121 b .

[0075] The width of the third cavity 123 is smaller than the second connecting section 122 of the second cavity 121b.

[0076] In this embodiment, the width of the second connecting section 122 of the second cavity 121b is adapted to the width of the metal coplanar waveguide 20, and the third cavity 123 is arranged below the second connecting section 122 of the second cavity 121b and has a width smaller than the second connecting section 122 of the second cavity 121b. In this way, two stepped surfaces can be formed at one end of the third cavity 123 facing the second connecting section 122 of the second cavity 121b. The stepped surfaces can be used to support the dielectric substrate in the second cavity 12.

[0077] Moreover, by setting the third cavity 123 corresponding to the main body 21 of the metal coplanar waveguide 20, on the one hand, a resonant cavity can be formed simultaneously by the first cavity 121 and the third cavity 123, which is beneficial for the terahertz chip packaging module 100 to achieve a larger 3dB bandwidth; on the other hand, the structure at the second connection portion 23 of the metal coplanar waveguide 20 and the bottom wall of the second connection section 122 of the second cavity 121b can be in contact to form a non-suspended structure, so that the structure of the second cavity 12 is more suitable for the second connection portion 23 for coupling microwave signals, thereby facilitating improving the microwave signal coupling efficiency and achieving a larger 3dB bandwidth.

[0078] Referring to Figures 1 to 5 , in some embodiments of the terahertz chip packaging module 100 of the present invention, the first chamber 11 includes a first segment 111 and a second segment 112 that are sequentially connected along its length. The first segment 111 is bent and connected to the second chamber 12. An end of the second segment 112 facing away from the first segment 111 forms the first interface 11a.

[0079] The second segment 112 is wider than the first segment 111 .

[0080] In this embodiment, the first section 111 of the first chamber 11 is connected to the second chamber 12, and the microstrip waveguide probe formed by the first connecting portion 22 of the metal coplanar waveguide 20 can be extended into the first section 111. In addition, the length of the microstrip waveguide probe extended into the first chamber 11 can be set to be approximately equal to half the width of the first chamber 11. In this way, in order to ensure the coupling efficiency of the terahertz signal, the width of the first section 111 can be made smaller and the length of the microstrip waveguide probe can be correspondingly shortened, which is beneficial to reducing the metal loss of the metal coplanar waveguide 20; the width of the second section 112 of the first chamber 11 is greater than that of the first section 111, and the size of the second section 112 is consistent with the size of a standard metal rectangular cavity waveguide. In this way, a first interface 11a can be formed through the second section 112 for inputting and outputting terahertz signals.

[0081] 1 and 2 , in some embodiments of the terahertz chip packaging module 100 of the present invention, the second segment 112 and the first segment 111 are connected with each other through a curved transition.

[0082] In this embodiment, by transitionally connecting the first segment 111 and the second segment 112 with curved surfaces, an arc chamfer can be formed between the first segment 111 and the second segment 112. This is beneficial for satisfying impedance matching between waveguides in the first cavity 121, thereby improving the coupling efficiency between the terahertz chip 30 and the first cavity 11.

[0083] 1 and 2 , a reflective structure 111 a is formed at one end of the first segment 111 away from the second segment 112 . The width of the reflective structure 111 a gradually narrows in a direction away from the first segment 111 .

[0084] In this embodiment, the reflective structure 111a includes two curved reflective surfaces disposed on either side of the first segment 111. A microstrip waveguide probe formed by the first connecting portion 22 of the metal coplanar waveguide 20 extends into the first segment 111 and is spaced apart from the reflective structure 111a. The central angle of the curved reflective surfaces can be either an obtuse angle or a right angle. The specific angle can be set based on actual needs and is not limited here.

[0085] With this arrangement, a resonant cavity can be formed between the reflective structure 111a and the microstrip waveguide probe. By optimizing the resonant cavity distance, the signal coupling efficiency between the terahertz chip 30 and the first cavity 11 can be further improved. In some embodiments, the resonant cavity distance can be set to one-quarter of the wavelength of the frequency corresponding to the terahertz signal.

[0086] Referring to FIG. 2 , in some embodiments of the terahertz chip packaging module 100 of the present invention, the terahertz chip 30 includes:

[0087] A terahertz negative resistance diode 31 is provided in the metal coplanar waveguide 20 and is used to couple the terahertz signal and the microwave signal;

[0088] a low-pass filter structure 32 , provided in the metal coplanar waveguide 20 and located at an end of the terahertz negative resistance diode 31 facing the second interface 12 a , for reflecting the terahertz signal and transmitting the microwave signal; and

[0089] The ballast resistor 33 is disposed in the metal coplanar waveguide 20 and is located at an end of the low-pass filter structure 32 away from the terahertz negative resistance diode 31 .

[0090] The terahertz chip 30 includes two terahertz negative resistance diodes 31, located between the two ground electrodes 20b and the signal electrode 20a. These negative resistance diodes, operating in the terahertz frequency band, exhibit both nonlinearity and negative differential resistance, enabling the resulting terahertz chip 30 to be fabricated into both a terahertz radiation source and a detector chip. These diodes can be resonant tunneling diodes (RTDs), Gunn diodes, impact ionization avalanche transit time (IMPATT) diodes, or other types of diodes, such as Schottky diodes and Fermi-level controllable barrier diodes. The specific implementation can be customized based on actual needs and is not limited here. The terahertz chip 30 also includes two ballast resistors 33, located between the two ground electrodes 20b and the signal electrode 20a, to suppress parasitic oscillations of the terahertz negative resistance diodes 31. Two terahertz negative resistance diodes 31 devices, a low-pass filter structure 32 and two ballast resistors 33 can be connected in series and in parallel through a transmission line formed by a metal coplanar waveguide 20 .

[0091] With such an arrangement, a terahertz coupling path and a microwave coupling path can be formed in the terahertz chip packaging module 100, wherein the terahertz coupling path sequentially includes a terahertz negative resistance diode 31, the first gradient region 211 of the main body 21 of the metal coplanar waveguide 20, a microstrip waveguide probe formed by the first connection portion 22 of the metal coplanar waveguide 20, a metal rectangular cavity waveguide formed by the first segment 111 of the first cavity 11, and a metal rectangular cavity waveguide interface formed by the second segment 112 of the first cavity 11; the microwave coupling path sequentially includes a terahertz negative resistance diode 31, a low-pass filter structure 32, a ballast resistor 33, the second gradient region 231 of the second connection portion 23 of the metal coplanar waveguide 20, and a metal electrode interface formed by the second connection portion 23 of the metal coplanar waveguide 20.

[0092] In some embodiments, the low-pass filter structure 32 includes a metal-dielectric-metal capacitor. The metal-dielectric-metal capacitor and the metal coplanar waveguide 20 can together form a low-pass filter that can be used to reflect terahertz signals and transmit microwave signals, thereby isolating the terahertz path from the microwave path. Of course, the technical solution of the present application is not limited to this, and the low-pass filter structure 32 can also be configured as other types of filter structures, which are not limited here.

[0093] Please refer to FIG. 6 , which shows the coupling efficiency calculation results of the terahertz chip packaging module 100 of the present application operating in the WR5 frequency band of 140-220 GHz.

[0094] As can be seen from the figure, the technical solution of this application can basically cover the entire operating frequency band of 140-220 GHz, and the coupling efficiency can be guaranteed to be above -1dB (80%). It should be noted that in related technologies, the highest coupling efficiency in the terahertz frequency band is generally -4dB (40%), and the 3dB bandwidth is only a few GHz. Therefore, the terahertz chip packaging module 100 of this application can achieve higher coupling efficiency and a larger 3dB bandwidth.

[0095] Please refer to Figure 7, which shows the electric field distribution of the terahertz chip packaging module 100 of the present application at the center frequency of 180 GHz of the frequency band. As can be seen from the figure, the terahertz chip packaging module 100 of the present application establishes good terahertz signal transmission between the terahertz negative resistance diode 31 of the terahertz chip 30 and the standard-sized metal rectangular cavity waveguide through the first gradient region 211 of the metal coplanar waveguide 20.

[0096] Please refer to Figure 8, which shows the calculated microwave coupling efficiency between the terahertz negative resistance diode 31 and the microwave signal at the metal electrode interface of the terahertz chip packaging module 100 of the present application. As can be seen from the figure, the terahertz chip packaging module 100 of the present application can achieve a 3dB bandwidth ≥ 40GHz through the second gradient region 231 of the metal coplanar waveguide 20.

[0097] The above description is merely an optional embodiment of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made using the contents of the present application specification and drawings under the inventive concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A terahertz chip packaging module, wherein: The terahertz chip packaging module includes: A metal shell having a first cavity and a second cavity connected by a bend formed therein, wherein an end of the first cavity facing away from the second cavity forms a first interface for inputting and outputting terahertz signals, and an end of the second cavity facing away from the first cavity forms a second interface for inputting and outputting microwave signals; a metal coplanar waveguide, the metal coplanar waveguide being arranged in the second cavity, with two ends of the metal coplanar waveguide being respectively connected to the first cavity and the second interface, for transmitting the terahertz signal and the microwave signal; and a terahertz chip, the terahertz chip being disposed in the metal coplanar waveguide and being used for coupling the terahertz signal and the microwave signal; The metal coplanar waveguide includes a signal electrode and two ground electrodes arranged side by side along the width direction of the second cavity, and the two ground electrodes are respectively arranged on both sides of the signal electrode at intervals; A first gradient region is formed at one end of the metal coplanar waveguide toward the first cavity. The width of the signal electrode gradually increases in the first gradient region toward the first cavity, and the width of the two ground electrodes gradually decreases in the first gradient region toward the first cavity.

2. The terahertz chip packaging module according to claim 1, wherein: The metal coplanar waveguide comprises: a main body, the main body being disposed in the second chamber and connected to the terahertz chip; a first connecting portion, the first connecting portion being provided at one end of the main body portion facing the first chamber and extending from the main body portion into the first chamber, for coupling the terahertz signal in the first chamber; and a second connecting portion, the second connecting portion being provided at one end of the main body facing the second cavity and exposed at the second interface, and being used for externally connecting to a microwave metal transmission line to couple the microwave signal; The first gradual change area is formed at one end of the main body facing the first connecting portion.

3. The terahertz chip packaging module according to claim 2, wherein: A second gradient region is formed on one end of the second connecting portion toward the main body; The width of the signal electrode is gradually increased from the second gradient region toward the second interface, and the width of the two ground electrodes is gradually decreased from the first gradient region toward the second interface.

4. The terahertz chip packaging module according to claim 2, wherein: The second chamber includes a first cavity and a second cavity that are sequentially connected from top to bottom, wherein the width of the first cavity is smaller than that of the second cavity, so as to form a step surface between the first cavity and the second cavity; The metal coplanar waveguide is arranged in the second cavity and forms an ohmic contact with the stepped surface.

5. The terahertz chip packaging module according to claim 4, wherein: The first cavity includes a first connecting section located above the main body, and a width of the first connecting section is smaller than a width of the metal coplanar waveguide.

6. The terahertz chip packaging module according to claim 4, wherein: The first cavity includes a second connecting section located above the second connecting portion, and a width of the second connecting section is not less than a width of the metal coplanar waveguide.

7. The terahertz chip packaging module according to claim 4, wherein: The second chamber further includes a third cavity, which is formed below the main body and communicates with the second cavity; The width of the third cavity is smaller than that of the second cavity.

8. The terahertz chip packaging module according to any one of claims 1 to 7, wherein: The first chamber comprises a first segment and a second segment that are sequentially connected along its length, the first segment being bent and connected to the second chamber, and an end of the second segment facing away from the first segment forming the first interface; The second segment is wider than the first segment.

9. The terahertz chip packaging module according to claim 8, wherein: The second segment body and the first segment body are connected with each other by a curved surface transition; And / or, a reflective structure is formed on one end of the first segment away from the second segment, and a width of the reflective structure is gradually narrowed in a direction away from the first segment.

10. The terahertz chip packaging module according to any one of claims 1 to 7, wherein: The terahertz chip includes: a terahertz negative resistance diode, provided in the metal coplanar waveguide, for coupling the terahertz signal and the microwave signal; a low-pass filter structure, provided in the metal coplanar waveguide and located at an end of the terahertz negative resistance diode facing the second interface, for reflecting the terahertz signal and transmitting the microwave signal; and The ballast resistor is provided in the metal coplanar waveguide and is located at an end of the low-pass filter structure away from the terahertz negative resistance diode.

Images