Superconducting radio frequency interface component

Abstract

The invention relates to a configurable electronic connection component, fabricated on a substrate, and intended for operation as a switch and / or attenuator. Said electronic component comprises a stack of layers including: - a first layer of a first superconducting cuprate-type material, - a second layer of a second material more electronegative than the first material and deposited on the first layer; - a third layer of an electrically conductive material deposited on the second layer, forming a control electrode; said first layer having a resistivity that varies according to the mole fraction of oxygen in said first material. Figure for the abstract: Fig. 3a

Description

Title of the invention: Superconducting radio frequency connection component

[0001] The present invention relates to the field of radio frequency (RF) signal transmission and reception, and in particular to a connection component integrated into a transmission device and intended for operation as a switch and / or attenuator. More specifically, the invention relates to a component made of a superconducting material for a transmission device operating at cryogenic temperatures.

[0002] RF signal transmission devices implemented using microstructures and nanostructures on a substrate generally comprise a plurality of signal transmission tracks. Each transmission track acts as a waveguide to confine and guide electromagnetic waves from a point of transmission to a point of reception. Generally, the transmission devices include a network of connecting components between the various microstructures that compose them, allowing their operation to be configured.

[0003] RF switches are an example of a connection component. RF switches are used to activate or deactivate transmission on a selected transmission track. This allows control of the information flow by activating one transmission track and deactivating the other transmission tracks. As an example of how RF switches operate, deactivating a transmission track is achieved by short-circuiting it to ground through a dedicated RF switch.

[0004] RF attenuators are also cited as an example of connection components. These are components that reduce the power of a signal transmitted by a transmission track without distorting the electromagnetic wave.

[0005] In the field of radio frequency transmission, the commonly used connecting components are PIN diodes (Positive Intrinsic Negative diodes). This technology requires the continuous injection of a bias current (on the order of 10 mA for each diode) through the diode. The bias currents in the PIN diode network induce energy losses through heat dissipation by the Joule effect.

[0006] More specifically, in the context of a transmission device operating at cryogenic temperatures, this heat dissipation poses a problem. Indeed, it is necessary to maintain the transmission device at a low operating temperature using a cooling system. The currents of Polarization of the connecting components heats the transmission device, increasing the energy consumption of the cooling system. The energy expended by the cooling system to compensate for the heat losses associated with the polarization of the connecting components represents a significant portion of the overall cooling energy budget.

[0007] Thus, there is a need to reduce the energy consumption due to the polarization of the connection components in an RF signal transmission device and more particularly in the context of operation at cryogenic temperatures.

[0008] We will begin by introducing the solutions known to those skilled in the art presenting alternative technologies to PIN diodes for making connection components.

[0009] A first known solution involves manufacturing connecting components using MEMS (Micro-Electro-Mechanical System) microelectromechanical systems. This solution has the disadvantage of a considerable degradation in insulation performance and insertion losses at low temperatures. Furthermore, the manufacturing process for MEMS components is complex and expensive. In addition, the MEMS connecting components themselves require a bias current during the operation of the transmission device.

[0010] A second known solution involves implementing connection components using GaN HEMT transistors. This solution has the disadvantage of poor isolation in the blocking state for high frequencies. This makes GaN HEMT technology incompatible with radio frequency (RF) signal transmission devices.

[0011] A third known solution involves manufacturing connecting components using structures based on germanium telluride. This material exhibits a crystalline phase and an amorphous phase depending on the applied temperature. To switch from one phase to the other, a series of heating and cooling steps is necessary. Therefore, this solution has the disadvantage of a considerable increase in energy consumption due to the heating and cooling cycles. Furthermore, the heating temperature can reach 200°C, making this solution unsuitable for operation at cryogenic temperatures.

[0012] To overcome the limitations of existing solutions regarding the energy consumption induced by connection components in an RF signal transmission device, the invention proposes a configurable connection component for controlling the signal flow in an RF signal transmission device. The component according to the invention is made by a A stack of layers comprising a layer of a superconducting cuprate material. The superconducting cuprate layer exhibits three configurable conductivity states: the first is a superconducting state, the second is an insulating state, and the third is an intermediate resistive state. The different conductivity states are remanent and reversible. Thus, the component according to the invention does not require the application of a supply voltage (or current) to maintain its conductivity state. The remanence of the conductivity states of the connecting component according to the invention thus solves the problem of energy consumption due to the biasing of connecting components in an RF signal transmission device.

[0013] The device according to the invention enables switching operation by toggling between the superconducting state (conducting switch) and the insulating state (blocking switch). Superconductivity provides a better connection in the conducting state than the semiconductor materials used in state-of-the-art solutions.

[0014] The device according to the invention allows for attenuator operation by varying its electrical resistance continuously when it is in the intermediate resistive state.

[0015] The device according to the invention also has the advantage of a stability of the physical phase (solid, liquid, gas) since it remains in the solid state for all conductivity states.

[0016] The invention further relates to a method for manufacturing a waveguide on a substrate comprising at least one connection component according to the invention. The manufacturing method is compatible with microelectronic integrated circuit manufacturing techniques. This offers the advantage of simple implementation of the method by semiconductor industry production lines. Thus, the method according to the invention has lower implementation and manufacturing costs compared to the alternative solutions previously discussed.

[0017] The invention relates to a configurable electronic connection component, fabricated on a substrate, and intended for operation as a switch and / or attenuator, said electronic component comprising a stack of layers including: - a first layer made of a first material of the superconducting cuprate type, - a second layer made of a second material that is more electronegative than the first material and deposited on the first layer; - a third layer made of an electrically conductive material and deposited on the second layer forming a control electrode; Said first layer having a resistivity that varies according to the mole fraction of oxygen in said first material so as to obtain one of the following conductivity states: a superconducting state or an insulating state or an intermediate resistive state.

[0018] The first material exhibiting remanent conductivity states.

[0019] According to a particular aspect of the invention, the first material exhibits reversible conductivity states.

[0020] According to a particular aspect of the invention, the first material is in the solid state for each conductivity state.

[0021] According to a particular aspect of the invention, the thickness of the first layer is between 50 nm and 700 nm.

[0022] According to a particular aspect of the invention, the thickness of the second layer is between 2 nm and 50 nm.

[0023] According to a particular aspect of the invention, the electronic component further comprises a fourth layer of a dielectric material confined between the second layer and the third layer.

[0024] According to a particular aspect of the invention, the thickness of the fourth layer is greater than 100nm.

[0025] According to a particular aspect of the invention, the first material is YBa2Cu3O7 ô or Bi2Sr2CaiCu2O8 s or NdBa2Cu3O7 s, with ô the variation of the mole fraction of oxygen in the first layer.

[0026] According to a particular aspect of the invention, the second material is chosen from aluminium or silver or yttrium or gold or molybdenum or silicon.

[0027] According to a particular aspect of the invention, the substrate is made of sapphire or MgO or SrTiO3 or Silicon.

[0028] According to a particular aspect of the invention, the electronic component further comprises a buffer layer confined between the substrate and the first layer when the substrate is made of Silicon.

[0029] According to a particular aspect of the invention, the buffer layer is made of cerium oxide or yttrium-stabilized zirconia.

[0030] According to a particular aspect of the invention, the stacking of layers forms a parallelepiped having a base of length greater than 1 Opm.

[0031] The invention also relates to a radio frequency signal transmission device implemented on a substrate comprising: - a first microstructure configured to propagate a radio frequency signal; - a second microstructure connected to an electrical niasse voltage; - an electronic connection component according to the invention such as: • the first microstructure is connected to the second microstructure via the first layer of the component; • The control electrode is configured to receive a control signal to control the conductivity states of the first layer.

[0032] According to a particular aspect of the invention, the transmission device further comprises control means configured to generate the control signal in two configurations:

[0033] a first configuration enabling the first layer to achieve a superconducting state so as to short-circuit the first microstructure with the second microstructure; and a second configuration enabling the first layer to achieve an insulating state so as to electrically isolate the first microstructure from the second microstructure. The electronic component having a switch function.

[0034] According to a particular aspect of the invention, the transmission device further comprises control means configured to generate the control signal so as to vary the variable resistivity of the electronic component over a range of values ​​corresponding to the intermediate resistive state. The electronic component has an attenuator function.

[0035] According to a particular aspect of the invention, the first microstructure and the second microstructure each comprise: - a guiding structure made with the first superconducting cuprate-type material; - a metallic layer deposited on the guide structure forming a feed electrode.

[0036] The invention also relates to a method for manufacturing a radio frequency signal transmission device comprising the following steps: a. fabricate at least a first microstructure and a second microstructure and at least a first layer linking said microstructures s. the first layer being made of a first material of the superconducting cuprate type. b. deposit, on each first layer, a second layer of a second material that is more electronegative than the first material. c. deposit, on each second layer, a third layer of an electrically conductive material. Each stack of the first, second and third layers forms a configurable electronic connection component linking two adjacent guide structures.

[0037] According to a particular aspect of the invention, step a) comprises the following substeps: i. deposit an intermediate layer of the first superconducting cuprate-type material distributed on a substrate; ii. deposit an intermediate metallic layer on the intermediate layer of the first material; iii. selectively etch the metallic layer to create at least two feed electrodes; iv. selectively etch the layer of the first material to: • create, for each feed electrode, a guiding structure composed of the first material; • and to create, between at least two adjacent guiding structures, at least one first layer linking said two adjacent guiding structures; each microstructure comprising: a guiding structure made with the first material and a feed electrode.

[0038] Other features and advantages of the present invention will become more apparent from the following description in relation to the following accompanying drawings.

[0039] [Fig.la] [Fig.la] illustrates a perspective view of a first embodiment of the connection component according to the invention.

[0040] [Fig. 1b] [Fig. 1b] illustrates a cross-sectional view of the first embodiment of the connection component according to the invention.

[0041] [Fig. le] The [Fig. le] illustrates a top view of the first embodiment of the connection component according to the invention.

[0042] [Fig.2a] [Fig.2a] illustrates a cross-sectional view of a second embodiment of the connection component according to the invention.

[0043] [Fig.2b] [Fig.2b] illustrates a cross-sectional view of a third embodiment of the connection component according to the invention.

[0044] [Fig.3a] [Fig.3a] illustrates a perspective view of a first embodiment of an RF signal transmission device comprising a connection component according to the invention.

[0045] [Fig.3b] [Fig.3b] illustrates a top view of the first embodiment of an RF signal transmission device comprising a connection component according to the invention.

[0046] [Fig.4] [Fig.4] illustrates a perspective view of a second embodiment of an RF signal transmission device comprising a connection component according to the invention.

[0047] [Fig. 5] [Fig. 5] illustrates the variation in attenuation of a transmission device of RF signals when the connection component according to the invention operates as an attenuator.

[0048] [Fig.6] Fig.6 illustrates a manufacturing process of the first embodiment of an RF signal transmission device

[0049] Figure 1a illustrates a perspective view of a first embodiment of the connecting component 10 according to the invention in an (x, y, z) coordinate system. The connecting component 10 is formed by a stack of thin films on a substrate SUB. The axis of component A is the axis perpendicular to the horizontal (x, y) plane formed by the upper surface of the substrate SUB. The connecting component 10 comprises the following layers, starting from the substrate and along the direction of the axis of component A: a first layer C1 of a superconducting material; a second layer C2 of a material more electronegative than the superconducting material; and a third layer C3 of an electrically conductive material.

[0050] Advantageously, the substrate is made of sapphire, MgO, SrTiO3, or silicon. Thus, the connection component 10 can be manufactured using a process compatible with semiconductor manufacturing processes.

[0051] The first Cl layer constitutes the active region of the connecting component 10. The first Cl layer is made of a first superconducting cuprate material. Superconducting cuprates are "high-temperature superconductors" consisting of alternating layers of copper oxide (CuO2) with layers of charge reservoirs that are oxides of other metals. A "high-temperature superconductor" is defined as a material exhibiting a critical temperature of superconductivity (Tc) that is relatively high compared to conventional superconductors (greater than 30 K).

[0052] Generally speaking, a superconducting cuprate material exhibits a resistivity that varies depending on the mole fraction of oxygen in its chemical composition. The sensitivity of the resistivity to the mole fraction of oxygen is significantly greater in cuprates compared to other superconducting materials. For a given operating temperature, this characteristic allows the following conductivity states to be obtained in the first Cl layer: a superconducting state, an insulating state, or an intermediate resistive state.

[0053] The superconducting state corresponds to an almost zero electrical resistance of the first Cl layer. The insulating state corresponds to a very high electrical resistance of the first CL layer. In the intermediate resistive state, the resistance varies continuously according to the variation of the mole fraction of oxygen in the chemical composition of the first material.

[0054] The conductivity states of the first superconducting cuprate-type material are remanent states. Thus, the conductivity state is maintained without the need for a continuous supply voltage (or current). The connecting component 10 is non-volatile and its energy consumption is reduced.

[0055] The conductivity states of the first superconducting cuprate-type material are reversible states. This allows switching from one conductivity state to another.

[0056] The conductivity states of the first superconducting cuprate-type material always correspond to a solid physical state. This stability of the physical state of the first material allows its integration into a thin-film stacked component.

[0057] By way of non-limiting examples, the first Cl layer is made of YBa2Cu3O7 (or YBCO) or Bi2Sr2CaiCu2O8 or NdBa2Cu3O7, where θ is a positive real number representing the variation in the mole fraction of oxygen in the first Cl layer. For a given operating temperature, when θ is less than a first limiting value, the first material is in a superconducting state. For a given operating temperature, when θ is greater than a second limiting value, the first material is in a superconducting state. When θ is between the first and second limiting values, the first material is in an intermediate resistive state. For example, for a Cl layer made of YBCO at an operating temperature T=70K, the first limiting value is 0.3 and the second limiting value is 0.6.

[0058] The sensitivity of the resistivity of the first material to the mole fraction of oxygen in its chemical composition is exploited to realize the configurable active area of ​​the connecting component 10.

[0059] The second layer C2 is deposited directly onto the first layer CL. The second layer C2 is made of a second material that is more electronegative than the first material. The electronegativity of a material is its ability to attract negative charge carriers. By way of non-limiting examples, the second layer C2 is made of aluminum, silver, yttrium, gold, molybdenum, or silicon.

[0060] The third layer C3 is deposited on the second layer C2. The third layer C3 is made of an electrically conductive material to form a control electrode EL3 receiving a control voltage Vc. For example, the voltage of Vcest control in the form of a square pulse defined by an amplitude and a duration of application.

[0061] We will now explain the operating mechanism of the C1 / C2 / C3 layer stacking to obtain a configurable connection component 10. When a positive control voltage Vc is applied to the control electrode EL3, an electric field is created across the C1 / C2 / C3 layer stack. This electric field induces the creation of oxygen vacancies and causes negative oxygen ions to move from the crystal lattice of the first Cl layer to the interface with the second C2 layer. The second C2 layer is more electronegative than the first Cl layer; therefore, the negative oxygen ions from the first Cl layer are absorbed by the second C2 layer. Thus, the mole fraction of oxygen in the first Cl layer is modified. This results in an increase in the resistivity of the first Cl layer due to the action of the control voltage Vc applied to the control electrode EL3.Conversely, when a negative control voltage Vc is applied to the control electrode EL3, the resistivity of the first Cl layer decreases by the reverse mechanism.

[0062] As illustrated, the first layer Cl has a width 11 and a length L1; the second layer C2 has a width 12 and a length L2; and the third layer C3 has a width 13 and a length L3. The dimensioning example shown has equal widths 11, 12, and 13 to simplify the manufacturing process. For a given conductivity state, the conductivity of the first layer Cl increases with its width 11. The length L1 of the first layer Cl is greater than those of layers C2 and C3 so that two ends of the first layer Cl extend beyond the stack of the Cl / C2 / C3 layers. The first end forms a first connecting electrode E1. The second end forms a first connecting electrode EL2. This results in a connecting component 10 having a control electrode EL3 for receiving the control voltage Vce and two connecting electrodes E1 and EL2.

[0063] The case is described where the connecting component 10 is intended for operation as a switch. The control voltage Vc has a sufficiently high amplitude and / or duration to cause the first layer Cl to switch between extreme conductivity states: a superconducting state or an insulating state. This results in configurable switch operation. By analogy with the operation of a CMOS transistor, the control electrode EL3 acts as the gate; the connecting electrodes ELI and EL2 act as the source and drain.

[0064] The case is described where the connection component 10 is intended for operation as an attenuator. The control voltage Vc has a chosen amplitude and / or duration. in order to gradually vary the resistivity of the first Cl layer through the three conductivity states. This results in operation as a continuously variable impedance attenuator.

[0065] To better understand the dimensioning of the connection component 10, [Fig.lb] illustrates a cross-sectional view in the (x,z) plane of the first embodiment of the connection component 10. The first layer Cl has a thickness el, the second layer C2 has a thickness e2 and the third layer has a thickness e3.

[0066] Advantageously, the thickness el of the first Cl layer is greater than 50 nm to ensure the mechanical robustness of the epitaxially deposited layer. Indeed, if the first Cl layer is not sufficiently thick, it would exhibit mechanical weaknesses. Furthermore, this allows the critical superconductivity temperature Tc of the first layer to be maintained at a high value.

[0067] Advantageously, the thickness el of the first Cl layer is less than 700 nm to avoid a rough top surface. Indeed, if the top surface of the first Cl layer is rough, the interface between the first Cl layer and the second C2 layer would exhibit surface adhesion defects during deposition. These defects reduce the electrical performance of the connecting component and its mechanical robustness. Moreover, surface defects in the form of protrusions can create a local concentration of electric fields, with risks of layer destruction. In addition, the protrusions can create discontinuities in the second C2 layer. These discontinuities induce short circuits at the interface between the two Cl and C2 layers.

[0068] Advantageously, the thickness e2 of the second layer C2 is greater than 2 nm to ensure sufficient oxygen ion attraction. This is necessary to perform the "pumping" function of oxygen ions from the first layer CL. Furthermore, a second layer C2 that is too thin exhibits an irregular structure during deposition, with a risk of creating areas of mechanical and electrical weakness.

[0069] Advantageously, the thickness e2 of the second layer C2 is less than an upper limit value to avoid obtaining irreversible conductivity states. Indeed, if the second layer C2 is too thick, it will have a very strong potential for attracting oxygen ions. The control voltage may become ineffective in controlling the conductivity state of the first layer C1. There is thus a risk of remaining stuck in an insulating conductivity state for a very thick second layer C2. The dimensioning of the second layer therefore depends on the electronegativity of the second material that constitutes it. For example, in the case of silver, the thickness e2 of the C2 layer is between 2 nm and 50 nm. In the case of aluminium, which is more electronegative than silver, the thickness e2 of the C2 layer is between 2nm and 10nm.

[0070] Figure 1a illustrates a top view of the first embodiment of the connecting component 10. The stacking of the C1 / C2 / C3 layers presents a mesa-like structure resting on the first layer Cl, with equal widths for the three layers that constitute said structure. Generally, the greater the width of the structure, the lower its resistance. Advantageously, the width of the three layers 11=12=13 is chosen to be 1 Opm. The length L1 of the first layer Cl is greater than those of the second and third layers in order to create the two connecting electrodes E1 and EL2.

[0071] Figure 2a illustrates a cross-sectional view of a second embodiment of the connecting component 11. In this embodiment, the stack of layers of the connecting component 11 further includes a fourth layer C4 made of dielectric material. The fourth layer is confined between the second layer C2 and the third layer C3. The advantage of inserting the fourth dielectric layer C4 is to prevent the injection of high currents from the control electrode EL3 into the structure of the connecting component 11. By analogy, this dielectric layer plays a role similar to the oxide layer at the gate of a CMOS transistor. This layer thus increases the reliability of the component and its technological robustness, thereby extending its lifespan. For example, the fourth layer C4 is made of silicon dioxide, aluminum oxide, or silicon nitride.Advantageously, the thickness e4 of the fourth layer C4 is greater than 100nm to protect the first layer Cl and the second layer C2 from strong currents from the control electrode during the application of a control voltage.

[0072] Figure 2b illustrates a cross-sectional view of a third embodiment of the connecting component 12. In this embodiment, the substrate SUB is made of silicon. The layer stack of the connecting component 12 further includes a CT buffer layer confined between the substrate SUB and the first layer CL. The CT transition layer enables the crystal lattice of the first material of the first layer Cl to adapt to that of the substrate during epitaxial growth. Advantageously, the CT buffer layer is made of cerium oxide or yttrium-stabilized zirconia. Moreover, the CT buffer layer allows the first layer Cl to be chemically isolated from the substrate SUB.

[0073] We have described the second and third embodiments separately for clarity. A fourth embodiment is conceivable in which the connecting component comprises the following stacking of layers from the substrate: the CT buffer layer, the first layer Cl in superconducting material, second layer C2 in material more electronegative than that of the first layer, fourth layer C4 in dielectric, third layer C3 forming the control electrode.

[0074] Fig. 3a illustrates a perspective view of a first embodiment of an RF signal transmission device, denoted 1, comprising at least one connection component according to the invention.

[0075] The radio frequency signal transmission device 1 is implemented on the SUB substrate. The device 1 comprises: a first microstructure 20 configured to propagate a radio frequency signal Vs, two electrical ground microstructures 30 and 30', each connected to the overall electrical ground of the device 1, and a plurality of connecting components 10 according to the invention. The first microstructure 20 constitutes a transmission track, and the two microstructures 30 and 30' constitute ground tracks. The transmission track 20 is disposed between the two ground tracks 30 and 30'. By way of illustration and without loss of generality, the device 1 comprises four connecting components 10. The transmission track 20 is connected to the first adjacent ground track 30 through two connecting components 10. The transmission track 20 is connected to the second adjacent ground track 30' through two connecting components 10.

[0076] Advantageously, the substrate is made of sapphire or MgO or SrTiO3 or silicon.

[0077] The device 1 further includes control means (not shown here) for generating the control signals (Vci, Vc2, Vc3, Vc4) associated respectively with each connection component 10. By way of example, the various connection components 10 allow the transmission of the signal Vs through the transmission track 20 to be activated or deactivated. When the connection components 10 are configured by the control signals to an insulating resistive state, the transmission track 20 is electrically isolated from the adjacent ground tracks 30 and 30'. Transmission is activated, and the signal Vs is then propagated through the transmission track 20 to the receiving point. When the connection components 10 are configured by the control signals to a superconducting resistive state, the transmission track 20 is electrically connected to the adjacent ground tracks 30 and 30'.Transmission is disabled and the Vs signal is not propagated through transmission track 20 to the receiving point.

[0078] Alternatively, the various connecting components 10 allow the signal Vs transmitted through the transmission track 20 to be attenuated. The connecting components 10 are configured by the control signals to an intermediate resistive state. Thus, the impedance of the connecting components 10 is continuously variable within the range of Values ​​defining the intermediate resistive state. This allows control of the attenuation of the transmitted signal amplitude Vs.

[0079] Fig. 3b illustrates a top view of the first embodiment of an RF signal transmission device comprising a plurality of connection components 10. We limit ourselves to presenting the transmission device 1 from one side only according to the direction of propagation PROP for the sake of simplification.

[0080] The transmission track 20 includes a guiding structure 20 made of an electrically conductive material. The guiding structure 20 serves to confine and propagate the electromagnetic waves of the propagated signal Vs towards the receiving point along the propagation direction PROP.

[0081] The transmission track 20 further comprises a feed electrode 22 made of an electrically conductive material deposited on the guide structure 20. In the illustrated case, the feed electrode 22 is deposited at the end of the transmission track 20 on the receiving end side. The feed electrode 22 is configured to supply the propagated signal Vs to a receiving terminal not shown here. Conversely, when the feed electrode 22 is deposited at the end of the transmission track 20 on the transmitting end side, it is configured to receive the propagated signal Vs generated by a transmitting terminal.

[0082] The ground track 30 comprises a guide structure 31 made of a conductive material and a power supply electrode 32 configured to receive the electrical ground voltage of the device. The ground track 30' is identical to the ground track 30.

[0083] Generally, to connect a first structure 20 to an adjacent second structure 30 via a connecting component 10, said component is arranged as follows: the first connecting electrode ELI is brought into contact with the guide structure 21 of the first structure 20 and the second connecting electrode EL2 is brought into contact with the guide structure 31 of the first structure 30. The connection between the first structure 20 and the adjacent second structure 30' on the other side is made in the same way.

[0084] Advantageously, the guiding structures 21, 31, and 31' are made of the same superconducting material used to produce the first Cl layer of each connecting component 10. This allows the superconductivity of the first material to be exploited for more efficient transmission. Furthermore, this allows the first Cl layer of each connecting component and the guiding structures 21, 31, and 31' to be made from the same layer of the superconducting material. The manufacturing process of the radio frequency signal transmission device 1 is thus simplified, and costs are reduced.

[0085] Figure 4 illustrates a perspective view of a second embodiment of an RF signal transmission device 2 comprising a connection component 10 according to the invention.

[0086] The transmission device 2 comprises a transmission track 20, a connection component 10 according to the invention, and a microstructure 40 in the form of a "mesh". The microstructure 40 is formed by stacking a first layer 41 made of the first superconducting material and a metallic layer 42 forming a power electrode. The transmission track 20 of the second embodiment is identical to that of the first embodiment.

[0087] The microstructure 40 is connected to the transmission track 20 through the connection component 10. The first connecting electrode ELI is brought into contact (or continuity) with the guide structure 21 and the second connecting electrode EL2 is brought into contact (or continuity) with the first layer 41 of the microstructure 40.

[0088] The transmission track 20, the connecting component 10, and the microstructure 40 are fabricated on a first face SUB_a of the substrate SUB. The transmission device 2 further comprises a metallic ground plane 50 deposited on the opposite face SUB_b of the substrate SUB. Advantageously, the substrate is made of sapphire, MgO, SrTiO3, or silicon. The feed electrode of the structure 40 is electrically connected to the ground plane 50, for example, via a wire 51 fabricated using the so-called "wire bonding" technique.

[0089] Thus, it is possible to activate or deactivate transmission through the transmission track 20 by configuring the conductivity state of the connection component 10 between an insulating or superconducting state.

[0090] Alternatively, it is possible to attenuate the signal Vs transmitted through the transmission track 20. The connecting components 10 are configured by the control signals to an intermediate resistive state. Thus, the impedance of the connecting components 10 is continuously variable within the range of values ​​defining the intermediate resistive state. This allows control of the attenuation of the amplitude of the transmitted signal Vs.

[0091] By way of example, [Fig.5] illustrates the variation in the attenuation of the RF signal transmission device 10 when the connection component 10 is configured for attenuator operation.

[0092] When the connecting component 10 is configured in a superconducting ES state, the connecting trace 20 is short-circuited to ground, and an attenuation greater than 40 dB and up to 50 dB is observed. The resistance of the connecting component is on the order of ImQ. Thus, the connecting component 10 exhibits a better performance compared to PIN diodes and germanium telluride-based structures while consuming less energy.

[0093] When the connection component 10 is configured in an intermediate resistive state ER, the resistance covers a wide range of variation from ImQ to 80Q. This allows access to a continuum of resistance values ​​to precisely configure the attenuation.

[0094] When the connecting component 10 is configured in an insulating state E1, the connecting trace 20 is isolated from ground and an attenuation of less than 3 dB is observed. The resistance of the connecting component is on the order of 100 Ω. Thus, the connecting component 10 exhibits insulation comparable to PIN diodes while consuming less power.

[0095] Figure 6 illustrates a manufacturing process for the first embodiment of the transmission device 10 described previously. It starts with a substrate SUB in wafer form. To facilitate understanding of the process, one or two cross-sectional views of the result of each step are shown. The first cross-sectional view corresponds to the cutting axis AA at the end of the transmission track as illustrated in Figure 3b. The second cross-sectional view corresponds to the cutting axis BB at a connecting component as illustrated in Figure 3b.

[0096] The first step (i) consists of depositing an intermediate layer Cl_int of the first superconducting cuprate-type material distributed over the entire surface of the SUB substrate. The deposition of the intermediate layer Cl_int in superconducting cuprate is carried out by epitaxial growth, for example.

[0097] The second step (ii) consists of depositing an intermediate metallic layer CM_int over the entire upper surface of the intermediate layer Cl_int of the first material. The deposition of the intermediate metallic layer CM_int is carried out by sputtering or by chemical vapor deposition, for example.

[0098] The third step (iii) consists of selectively etching the metallic layer to create the feed electrodes 22, 32 along axis AA. The intermediate metallic layer CM_int is removed by etching the remainder of the surface as illustrated in the cross-section along axis BB. The etching can be carried out using an ion beam etching technique, for example.

[0099] The fourth step (iv) consists of selectively etching the layer of the first material to create, for each feed electrode, a guiding structure 21, 31, and 31' with the first superconducting material. The section along axis AA shows the separation between the different guiding structures 31, 21, and 31'. Simultaneously, this step makes it possible to create, between at least two adjacent guiding structures 21, 31, and 31', at least one first layer Cl connecting said two adjacent guide structures 21, 31 and 31' as illustrated by the cross-sectional view according to BB.

[0100] The fifth step (v) consists of reducing the thickness of the first Cl layers by ion beam etching, which offers greater etching precision. This is an optional step to obtain a flat surface. This step also ensures homogeneity in the variation of oxygen ions in the first Cl layers.

[0101] The sixth step (vi) consists of depositing, on each first Cl layer, a second C2 layer in a second material more electronegative than the first material.

[0102] The seventh step (vii) consists of depositing, on each second layer C2, a third layer C3 of an electrically conductive material in order to form the control electrodes EL3 of each connection component 10. Thus, with each stacking of the first, second and third layers, a configurable electronic connection component 10 is obtained, linking two adjacent guide structures.

[0103] All the steps of the process according to the invention are compatible with the usual microelectronic manufacturing techniques in the semiconductor industry. This makes it possible to reduce the cost of implementing and carrying out the manufacturing process according to the invention.

Claims

Demands

1. Configurable electronic connection component (10), made on a substrate (SUB), and intended for operation as a switch and / or attenuator, said electronic component (1) comprising a stack of layers including: - a first layer (Cl) of a first superconducting cuprate type material, - a second layer (C2) of a second material more electronegative than the first material and deposited on the first layer (Cl); - a third layer (C3) of an electrically conductive material and deposited on the second layer (C2) forming a control electrode; - a fourth layer (C4) of a dielectric material confined between the second layer (C2) and the third layer (C3);said first layer (Cl) having a resistivity that varies according to the mole fraction of oxygen in said first material so as to obtain one of the following conductivity states: a superconducting state (ES) or an insulating state (El) or an intermediate resistive state (ER); the first material having remanent conductivity states.

2. Electronic connection component (10) according to claim 1 in which the first material exhibits reversible conductivity states.

3. Electronic connection component (10) according to any one of claims 1 or 2 wherein the first material is in the solid state for each conductivity state.

4. Electronic connection component (10) according to any one of the preceding claims wherein the thickness of the first layer (Cl) is between 50 nm and 700 nm.

5. Electronic connection component (10) according to any one of the preceding claims wherein the thickness of the second layer (C2) is between 2 nm and 50 nm.

6. Electronic connection component (10) according to the preceding claim in which the thickness of the fourth layer (C4) is greater than 100nm.

7. Electronic connection component (10) according to any one of the preceding claims wherein the first material is YBa2Cu3O7 ô or Bi2Sr2CaiCu2O8 ô or NdBa2Cu3O7 ô> with ô the variation of the mole fraction of oxygen in the first layer (Cl).

8. Electronic connection component (10) according to any one of the preceding claims wherein the second material is selected from aluminium or silver or yttrium or gold or molybdenum or silicon.

9. Electronic connection component (10) according to any one of the preceding claims wherein the substrate (SUB) is made of sapphire or MgO or SrTiO3 or Silicon.

10. Electronic connection component (10) according to the preceding claim further comprising a buffer layer (CT) confined between the substrate (SUB) and the first layer (Cl) when the substrate (SUB) is made of Silicon.

11. Electronic connection component (10) according to the preceding claim in which the buffer layer is made of cerium oxide or yttrium-stabilized zirconia.

12. Electronic connection component (10) according to any one of the preceding claims such that the stacking of layers forms a parallelepiped having a base of length greater than 1 Opm.

13. Radio frequency signal transmission device (1) made on a substrate (SUB) comprising: - a first microstructure (20) configured to propagate a radio frequency signal (Vs); - a second microstructure (30, 30') connected to an electrical ground voltage (Vgnd); - an electronic connection component (10) according to any one of the preceding claims such that: • the first microstructure (20) is connected to the second microstructure (30, 30') via the first layer (Cl) of the component; • the control electrode is configured to receive a control signal (Vc) allowing control of the conductivity states of the first layer (Cl);

14. Device (1) for transmitting radio frequency signals according to claim 13 further comprising control means configured to generate the control signal (Vc) in two configurations: a first configuration enabling the superconducting state of the first layer (Cl) so as to short-circuit the first microstructure with the second microstructure; and a second configuration enabling the insulating state of the first layer (Cl) so as to electrically isolate the first microstructure from the second microstructure; the electronic component (10) having a switch function.

15. Device (1) for transmitting radio frequency signals according to claim 13 further comprising control means configured to generate the control signal (Vc) so as to vary the variable resistivity of the electronic component (10) over a range of values ​​corresponding to the intermediate resistive state (ER); the electronic component (10) having an attenuator function.

16. Device (1) for transmitting radio frequency signals according to any one of claims 13 to 15 wherein the first microstructure (20) and the second microstructure (30, 30') each comprise: a guide structure (21,31,31') made with the first superconducting cuprate-type material; a metallic layer deposited on the guide structure (21,31,31') forming a feed electrode (22, 32, 32');

17. Method (PI) of manufacturing a radio frequency signal transmission device (1) comprising the following steps: a. fabricating at least a first microstructure (20) and a second microstructure (30, 30') and at least a first layer (Cl) linking said microstructures (20, 30, 30'); the first layer (Cl) being of a first superconducting cuprate type material;

18. b. deposit, on each first layer (Cl), a second layer (C2) of a second material that is more electronegative than the first material; c. deposit, on each second layer (C2), a third layer (C3) of an electrically conductive material; each stack of the first, second and third layer forming a configurable electronic connection component (1) linking two adjacent guide structures; Method (PI) for manufacturing a radio frequency signal transmission device (1) according to claim 17, wherein step a) comprises the following substeps: i. deposit an intermediate layer (Cl_int) of the first superconducting cuprate-type material distributed on a substrate (SUB); ii. deposit an intermediate metallic layer (CM_int) on an intermediate layer (Cl_int) of the first material; iii. selectively etch the metallic layer to make at least two feed electrodes (22, 32); iv. selectively etch the layer of the first material to: • to produce, for each feed electrode, a guiding structure (21,31,31') composed of the first material; • and to create, between at least two adjacent guidance structures (21,31,31'), at least one first layer (Cl) linking said two adjacent guidance structures (21,31,31'); each microstructure (20,30,30') comprising: a guiding structure (21,31,31') made with the first material and a feed electrode (22, 32, 32').

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