A non-volatile radio frequency switch chip for 5G radio frequency front end

Abstract

The application provides a nonvolatile radio frequency switch chip for a 5G radio frequency front end, wherein an input port, an input transmission line, a ReRAM core MIM unit group, an output transmission line and an output port are sequentially electrically connected; and the input transmission line, the ReRAM core MIM unit group and the output transmission line are peripherally surrounded in a ring shape. The RAM core MIM unit is a three-layer sandwich structure, and the bottom electrode layer, the dielectric layer and the top electrode layer are sequentially arranged from bottom to top; and the bottom electrode and the top electrode are completely separated by the intermediate dielectric layer without electrical connection. The application utilizes n ReRAM core MIM units arranged in the same direction and at equal distances to form the ReRAM core MIM unit group, reduces the switch conduction resistance, significantly reduces the insertion loss, introduces a gradually changing ground coplanar waveguide transmission line to reduce the gap capacitance effect, realizes the improvement of the isolation degree and improves the high-frequency impedance matching.

Description

TECHNICAL FIELD

[0001] The application relates to the field of radio frequency integrated circuit design, and particularly relates to a non-volatile radio frequency switch chip for a 5G radio frequency front end. BACKGROUND

[0002] With the development of communication technology and integrated circuits, the radio frequency switch is playing an increasingly important role in radio frequency chips. However, it is still difficult to realize a radio frequency switch chip with low loss and ultra-wideband, and meanwhile, the existing radio frequency switches all need continuous excitation to maintain the state. The disclosed non-volatile radio frequency switch is currently mainly focused on its manufacturing method.

[0003] A phase change radio frequency switch manufacturing method is disclosed in Chinese Patent No. CN201911242574.9, which comprises the following steps: a semiconductor heating resistor is prepared on a preset semiconductor insulating substrate, and a resistance power electrode is prepared at both ends of the semiconductor heating resistor, to obtain a first sample; an isolation layer is prepared on the surface of the first sample except the resistance power electrode, a phase change material film is prepared at the position corresponding to the semiconductor heating resistor on the isolation layer, and a contact electrode is prepared at both ends of the phase change material film, to obtain a second sample, the direction of the resistance power electrode is perpendicular to the direction of the contact electrode; a passivation layer is prepared on the surface of the second sample, to obtain a phase change radio frequency switch. However, in the embodiment of the present application, the phase change radio frequency switch is made of a semiconductor material to prepare an on-off state trigger resistance heater, so that the reliability of the phase change switch can be improved, the process can be simplified, and the process cost of the phase change radio frequency switch integrated chip can be reduced.

[0004] A kind of indirect heating type phase change radio frequency switch is disclosed in Chinese Patent No. CN202311096842.7, which comprises: substrate layer, cantilever beam, insulating layer, heating layer, isolation layer, phase change layer, electrode layer and passivation layer are sequentially overlapped from bottom to top;The top center of substrate layer is provided with the recessed cavity recessed to the bottom direction of substrate layer;Cantilever beam includes a suspension platform and two or more cantilevers;Suspension platform is arranged in the middle of cantilever beam, one corresponding end of cantilever is connected with the edge of suspension platform with interval, and the other corresponding end of cantilever is arranged on the side wall of recessed cavity;The top of cantilever beam is coplanar with the top of substrate layer, and the bottom of cantilever beam and the bottom of recessed cavity have a hollow cavity;Phase change layer is arranged at the top center of isolation layer;Phase change layer is an equal-width strip structure, and the strip structure includes one or more "S" structures connected in a head-to-tail manner.

[0005] Chinese patent application CN202410956325.0 discloses a zinc oxide / hafnium oxide-based radio frequency switch and its fabrication method. It uses a silicon-based wafer as a carrier, platinum and silver as electrode layers for the radio frequency switch chip, and molybdenum disulfide and zinc oxide as resistive switching materials. The switch comprises, from bottom to top, a silicon substrate layer, an aluminum nitride layer, a nickel layer, a platinum layer, a molybdenum disulfide layer, a zinc oxide layer, a silver layer, a titanium nitride layer, a nickel layer, and a copper layer. This invention fabricates the radio frequency switch on a silicon substrate using photolithography and PVD magnetron sputtering, resulting in a simple and low-cost fabrication method. The fabricated radio frequency switch exhibits excellent performance and promising application prospects.

[0006] In summary, currently available non-volatile RF switches focus on improving fabrication methods, with relatively little emphasis on optimizing device structure design. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes a non-volatile RF switch chip for 5G RF front-ends. Its core innovation lies in shifting the research focus from traditional materials and manufacturing processes to device structure optimization. Utilizing the unique resistive characteristics of nonlinear ReRAM devices, it innovatively employs a multi-finger structure design to reduce insertion loss. Furthermore, it introduces a gradient ground coplanar waveguide electrode to mitigate the gap capacitance effect, thereby reducing off-state capacitance and improving high-frequency impedance matching. The technical solution provided by this invention is as follows:

[0008] A non-volatile radio frequency switch chip for 5G radio frequency front-end, wherein an input port, an input transmission line, a ReRAM core area MIM unit group, an output transmission line, and an output port are electrically connected in sequence; and a ring ground surrounds the input transmission line, the ReRAM core area MIM unit group, and the output transmission line.

[0009] The ReRAM core area MIM cell group consists of n ReRAM core MIM cells arranged in the same direction and at equal intervals, where n is an integer greater than 1. The RAM core MIM cell has a three-layer sandwich structure, consisting of a bottom electrode layer, a dielectric layer, and a top electrode layer from bottom to top. There is no electrical connection between the bottom electrode and the top electrode, which are completely isolated by the middle dielectric layer. The vertical area of ​​the three layers is the overlap area. The area where the bottom electrode of the ReRAM core MIM cell extends out of the overlap area is connected to the output end of the input transmission line, and the area where the top electrode extends out of the overlap area is connected to the input end of the output transmission line.

[0010] Preferably, both the input transmission line and the output transmission line are of a gradient CPW structure; the line width at the connection between the input transmission line and the input terminal is greater than the line width at the connection between the input transmission line and the ReRAM cell group, and the line width at the connection between the output transmission line and the output terminal is greater than the line width at the connection between the output transmission line and the ReRAM cell group. The shape of the transmission line is rectangular, trapezoidal, horn-shaped, or any combination of the three.

[0011] Preferably, the bottom electrode layer of the ReRAM core MIM unit is rectangular, trapezoidal, or triangular in shape, and the bottom electrode layer material is composed of Ti, Au, Pt, W, or ITO, either individually or in combination.

[0012] Preferably, the top electrode layer of the ReRAM core MIM unit is rectangular, trapezoidal, or triangular in shape, and the top electrode layer material is composed of Cu, Ag, Al, Pt, or Au, either individually or in combination.

[0013] Preferably, the dielectric layer of the ReRAM core MIM unit is larger than the overlapping area between the top electrodes, and is composed of one or more combinations of metal oxides, two-dimensional materials, and organic materials, wherein the metal oxides include ZnO, HfO2, TiO2, and TaO. x Two-dimensional materials include MoS2, hBN, and black phosphorus, while organic materials include nafion, AIDCN, TPD, and PMMA.

[0014] Preferably, the RF switch chip uses a silicon-based wafer as a carrier and is fabricated using techniques such as optical lithography, magnetron sputtering, and metal evaporation.

[0015] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: By utilizing n ReRAM core MIM cells arranged in the same direction and at equal intervals to form a ReRAM core MIM cell group, the switching on-resistance is reduced, significantly lowering insertion loss. The introduction of a graded ground coplanar waveguide transmission line mitigates the gap capacitance effect, thereby improving isolation and enhancing high-frequency impedance matching. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of the general form of the circuit structure of the present invention;

[0018] Figure 2 This is a schematic diagram of the circuit structure of Embodiment 1 of the present invention;

[0019] Figure 3 This is a schematic diagram of the circuit structure of Embodiment 2 of the present invention;

[0020] Figure 4 This is a schematic diagram of the circuit structure of Embodiment 3 of the present invention;

[0021] Figure 5 This is a schematic diagram of the circuit structure of Embodiment 4 of the present invention;

[0022] Figure 6These are the S-parameter simulation results of the non-volatile RF switch chip of this invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] To make the above-mentioned objectives, features and effects of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1: A non-volatile radio frequency switch chip for 5G radio frequency front-end, such as Figure 2 As shown, the input port, input transmission line L1, ReRAM core area MIM unit group M, output transmission line L2 and output port are electrically connected in sequence; a ring ground 101 surrounds the input transmission line, ReRAM core area MIM unit group and output transmission line.

[0026] The ReRAM core area MIM unit group M consists of two ReRAM core MIM units M1 and M2 arranged in the same direction and at equal intervals. The RAM core MIM units M1 and M2 have a three-layer sandwich structure, from bottom to top: bottom electrode layer, dielectric layer, and top electrode layer. There is no electrical connection between the bottom electrode and the top electrode, which are completely isolated by the middle dielectric layer. The vertical area of ​​the three layers is the overlap area. The area where the bottom electrode of the ReRAM core MIM unit extends out of the overlap area is connected to the output end of the input transmission line, and the area where the top electrode extends out of the overlap area is connected to the input end of the output transmission line.

[0027] The input transmission line L1 and the output transmission line L2 are composed of a cascade of a traditional CPW transmission line structure and a gradient CPW structure, presenting a shape with a rectangular and trapezoidal connection. The line width of the input transmission line L1 at the connection with the input terminal is greater than the line width of the input transmission line at the connection with the ReRAM cell group M, and the line width of the output transmission line L2 at the connection with the output terminal is greater than the line width of the output transmission line at the connection with the ReRAM cell group M.

[0028] A ring ground 101 surrounds the input transmission line L1, the ReRAM core area MIM cell group M, and the output transmission line L2, and the ring ground extends gradually on both sides of the input transmission line L1 and the output transmission line L2, providing a ground-signal line spacing that varies to approximately 50 ohms of characteristic impedance.

[0029] The bottom electrode layer of the ReRAM core MIM cell is rectangular, trapezoidal, or triangular in shape. The bottom electrode layer material is composed of Ti, Au, Pt, W, or ITO, either individually or in combination. The top electrode layer is also rectangular, trapezoidal, or triangular in shape, and the top electrode layer material is composed of Cu, Ag, Al, Pt, or Au, either individually or in combination. The materials of the top and bottom electrodes can be the same; for example, Au or Pt can be used as both the bottom and top electrodes. The dielectric layer is larger than the overlapping area between the top and bottom electrodes and is composed of one or more combinations of metal oxides, two-dimensional materials, and organic materials. The metal oxides include ZnO, HfO2, TiO2, and TaO. x Two-dimensional materials include MoS2, hBN, and black phosphorus, while organic materials include nafion, AIDCN, TPD, and PMMA.

[0030] Figure 6 This is a simulation curve showing the relationship between the switching scattering parameters and frequency provided in Embodiment 1 of the present invention. Figure 6 As shown, S 11 S represents the return loss at the input port. 21 The insertion loss from the input port to the output port is represented by the single-pole single-throw switch disclosed in Embodiment 1 of the present invention. The insertion loss is less than 1dB in the DC-40GHz on state, the return loss is greater than 20dB, and the isolation is better than 4.5dB in the off state.

[0031] This RF switch chip uses a silicon-based wafer as a substrate and is fabricated using techniques such as optical lithography, magnetron sputtering, and metal evaporation. This non-volatile RF switch chip, designed for 5G RF front-ends, achieves low loss and high matching performance through a ReRAM core area MIM cell group and a gradient ground coplanar waveguide electrode.

[0032] Example 2: As Figure 3 As shown, it includes an input transmission line L1, a ReRAM core area MIM unit group M, an output transmission line L2, and a ring ground 201. Compared with Embodiment 1, the ReRAM core area MIM unit group M in this embodiment is composed of three ReRAM core area MIM units M1, M2, and M3.

[0033] Example 3: As Figure 4 As shown, it includes an input transmission line L1, a ReRAM core area MIM cell group M, an output transmission line L2, and a ring ground 301. Compared with Embodiment 1, in this embodiment, the input transmission line L1, the ReRAM core area MIM cell group M, and the output transmission line L2 are connected at right angles, and the input transmission line L1 and the output transmission line L2 present a rectangular-trapezoidal-rectangular connection shape.

[0034] Example 4: Figure 5As shown, it includes an input transmission line L1, a ReRAM core area MIM unit group M, an output transmission line L2, and a ring ground 401. Compared with embodiment 3, the ReRAM core area MIM unit group M in this embodiment is composed of three ReRAM core area MIM units M1, M2, and M3.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A non-volatile radio frequency switch chip for 5G radio frequency front end, characterized in that, The input port, the input transmission line, the ReRAM core area MIM unit group, the output transmission line and the output port are sequentially electrically connected; and the input transmission line, the ReRAM core area MIM unit group and the output transmission line are annularly surrounded in the periphery. The ReRAM core area MIM unit group is composed of n ReRAM core MIM units arranged in the same direction and at equal distances, wherein n is an integer greater than 1; the ReRAM core MIM unit is a three-layer sandwich structure, and the bottom electrode layer, the dielectric layer and the top electrode layer are sequentially arranged from bottom to top; the bottom electrode and the top electrode are not electrically connected and are completely separated by the intermediate dielectric layer, and the three layers are vertically arranged in an overlapping area. The bottom electrode of the ReRAM core MIM unit extends out of the overlapping area and is connected to the output end of the input transmission line, and the top electrode of the ReRAM core MIM unit extends out of the overlapping area and is connected to the input end of the output transmission line.

2. The nonvolatile RF switch chip for 5G RF front-end of claim 1, wherein, The input transmission line and the output transmission line are both gradually changing CPW structures; the line width of the input transmission line at the connection with the input port is greater than the line width of the input transmission line at the connection with the ReRAM unit group, and the line width of the output transmission line at the connection with the output port is greater than the line width of the output transmission line at the connection with the ReRAM unit group; the shape of the transmission line is rectangular, trapezoidal, horn-shaped or any combination of the three.

3. The non-volatile RF switch chip for 5G RF front end of claim 2, wherein, The bottom electrode layer of the ReRAM core MIM unit is rectangular, trapezoidal or triangular in shape, and the material of the bottom electrode layer is composed of Ti, Au, Pt, W, ITO in single or combined form.

4. The nonvolatile RF switch chip for 5G RF front-end of claim 2, wherein, The top electrode layer of the ReRAM core MIM unit is rectangular, trapezoidal or triangular in shape, and the material of the top electrode layer is composed of Cu, Ag, Al, Pt, Au in single or combined form.

5. The nonvolatile RF switch chip for 5G RF front-end of claim 2, wherein, The size of the medium layer of the ReRAM core MIM unit is greater than the top electrode and the top electrode overlapping area, which is composed of one or more combinations of metal oxide, two-dimensional material and organic material, wherein the metal oxide includes ZnO, HfO2, TiO2 and TaO x , the two-dimensional material includes MoS2, hBN and black phosphorus, and the organic material includes nafion, AIDCN, TPD and PMMA.

6. The nonvolatile RF switch chip for 5G RF front-end of claim 1, wherein, The radio frequency switch chip takes a silicon-based wafer as a carrier, and is prepared by optical lithography, magnetron sputtering or metal evaporation.

7. A multi-port switch, characterized by, A non-volatile radio frequency switch chip for a 5G radio frequency front end as claimed in any one of claims 1-6.

8. A radio frequency phase shifter characterized by, A non-volatile radio frequency switch chip for a 5G radio frequency front end as claimed in any one of claims 1-6.

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