Selective chemical frequency modification of Josephson junction resonators.

Abstract

Techniques are provided for selectively adjusting the operating frequency of a superconducting Josephson junction resonator. For example, one or more embodiments described herein may include a method that may include chemically altering Josephson junctions of the Josephson junction resonator via a plasma treatment. The method may also include selectively adjusting the operating frequency of the Josephson junction resonator based on attributes of the plasma treatment.

Description

[Technical field]

[0001] The present disclosure relates to chemically modifying the frequency of selected Josephson junction resonators (e.g., qubits), and more particularly to adjusting the operating frequency of selected Josephson junction resonators by changing the electrical resistance of the Josephson junctions via one or more plasma treatments. [Background technology]

[0002] The scaling of quantum computer technology facilitates complex architectures of multi-qubit processors, where maintaining low gate error rates in the limit supported by the coherence time is of special importance. Quantum processors using fixed-frequency superconducting Josephson junction-based transmon qubits and / or cross-resonant gates may experience gate error rates due to at least frequency collisions and / or frequency crowding. For example, adjacent qubits may be degenerate in one or more conditions that reduce gate fidelity.

[0003] To mitigate frequency collisions and / or frequency crowding, the fixed frequency of a superconducting qubit can be manipulated by modifying the Josephson junction resistance and / or transmon capacitance. For example, Josephson junctions can be laser annealed to increase their electrical resistance and lower the qubit frequency. However, laser annealing provides a very narrow tuning range (e.g., 15-20 percent) with respect to the initial Josephson junction resistance. Furthermore, fabrication of multi-qubit arrays can produce a large distribution of Josephson junction resistances from chip to chip. The limited tuning range provided by laser annealing may prove insufficient to tune qubits over a large resistance distribution and may also prevent setting the average Josephson junction resistance of the chip to the target frequency range (e.g., hundreds of megahertz for transmons with frequencies as high as 5 gigahertz). Summary of the Invention

[0004] The following presents a summary in order to provide a basic understanding of one or more embodiments of the present invention. This summary is not intended to identify key or critical elements or to delineate the scope of particular embodiments or claims. Its sole purpose is to present concepts in a simplified form as a prelude to the more detailed description presented later. In one or more embodiments described herein, a method, system, and / or apparatus for tuning the operating frequency of a Josephson junction resonator (e.g., a superconducting qubit) via one or more plasma processes is described.

[0005] According to one embodiment, a method is provided. The method may include chemically altering Josephson junctions of a Josephson junction resonator via a plasma treatment. The method may also include selectively tuning an operating frequency of the Josephson junction resonator based on an attribute of the plasma treatment. An advantage of such a method may be the ability to modify the operating frequency over a wide range with respect to an initial operating frequency.

[0006] In some examples, the attribute may be at least one member selected from the group consisting of a treatment time of the plasma treatment, a chemical composition of the plasma treatment, an amount of energy delivered to the Josephson junction by the plasma treatment, and a partial pressure of a gas used by the plasma treatment. An advantage of such a method may be considerable control over the amount of chemical modification achieved by the plasma treatment.

[0007] According to another embodiment, a method is provided. The method may include chemically altering Josephson junctions of a Josephson junction resonator via a plasma treatment. The method may also include adjusting an electrical resistance of the Josephson junctions based on an attribute of the plasma treatment. An advantage of such a method may be modification of a qubit chip to achieve a target average electrical resistance.

[0008] In some examples, the method may further include localizing the plasma treatment in proximity to the Josephson junction via a plasma beam. An advantage of such a method may be a quick transition between plasma treatment and electrical resistance measurement, such that repeated uses of plasma treatment may be assessed and performed in a rapid manner.

[0009] According to another embodiment, a method is provided. The method can include exposing a Josephson junction of a Josephson junction resonator to a plasma treatment. The plasma treatment can tune an operating frequency of the Josephson junction resonator to a target operating frequency by modifying an electrical resistance of the Josephson junction. An advantage of such a method can be tuning a fixed frequency superconducting qubit to mitigate occurrences of frequency collisions and / or frequency crowding.

[0010] In some examples, the method can further include shielding the second Josephson junction from the plasma treatment, where the second Josephson junction is proximate to the Josephson junction of the Josephson junction resonator. An advantage of such a method can be selective tuning of a target Josephson junction.

[0011] According to another embodiment, an apparatus is provided. The apparatus may include an actuator operably coupled to a cover sheet including a hole disposed on a platform configured to structurally support a Josephson junction resonator die. An advantage of such an apparatus may be the ability to precisely control the time the Josephson junction is exposed to a plasma treatment.

[0012] In some examples, the apparatus may further include a guide housing disposed adjacent to the cover sheet and configured to guide movement of the cover sheet initiated by the actuator. An advantage of such an apparatus may be that the apparatus can guide sequential modifications to target Josephson junctions on the qubit die.

[0013] According to another embodiment, a system is provided. The system may include an actuator operably coupled to a cover sheet including holes. The system may also include a computer readable storage medium having program instructions embodied therein. The program instructions may be executable by the processor to cause the processor to control operation of the actuator such that the actuator adjusts the position of the holes with respect to Josephson junctions on a Josephson junction resonator die shielded by the cover sheet. An advantage of such a system may be controlled implementation of one or more plasma treatments to selectively tune each Josephson junction resonator of a qubit array.

[0014] In some examples, the program instructions may further cause the processor to control operation of the actuator such that the actuator aligns the Josephson junction with the hole in the cover sheet. An advantage of such a system may be that multiple Josephson junction resonators may be adjusted in parallel or sequentially based on the alignment of the cover sheet. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 illustrates an example, non-limiting diagram of a first stage of a Josephson junction resonator frequency tuning process, in which one or more Josephson junction resonators (e.g., superconducting qubits) may be identified for exposure to one or more subsequent plasma treatments, according to one or more embodiments described herein. [Diagram 2] FIG. 10 illustrates an exemplary, non-limiting diagram of a second stage of a Josephson junction resonator frequency tuning process, in which one or more masks may be patterned to protect one or more Josephson junction resonators while exposing one or more identified Josephson junction resonators, according to one or more embodiments described herein. [Diagram 3]1 shows a diagram of an exemplary, non-limiting Josephson junction resonator die at least partially covered by one or more masks comprising one or more electrodes capable of controlling the movement of one or more reactive gas species of a plasma process according to one or more embodiments described herein. [Figure 4] 1 illustrates a diagram of an exemplary, non-limiting Josephson junction resonator die at least partially covered by one or more multi-layer masks according to one or more embodiments described herein. [Diagram 5] FIG. 10 illustrates an example, non-limiting diagram of a third stage of a Josephson junction resonator frequency tuning process, in which one or more exposed Josephson junction resonators may be subjected to one or more plasma treatments, according to one or more embodiments described herein. [Figure 6] FIG. 10 illustrates an exemplary, non-limiting diagram of a third stage of a Josephson junction resonator frequency tuning process, in which one or more plasma treatments may be localized, according to one or more embodiments described herein. [Figure 7] FIG. 1 illustrates an exemplary, non-limiting cross-sectional view of a cover sheet arrangement that can control the alignment of one or more cover sheets to facilitate one or more Josephson junction resonator frequency tuning processes according to one or more embodiments described herein. [Figure 8] FIG. 1 is an exemplary, non-limiting, top-down view of a cover sheet arrangement that can control the alignment of one or more cover sheets to facilitate one or more Josephson junction resonator frequency tuning processes according to one or more embodiments described herein. [Figure 9] FIG. 1 illustrates an exemplary, non-limiting top-down view of a cover sheet arrangement that can control the alignment of one or more cover sheets to facilitate one or more Josephson junction resonator frequency tuning processes according to one or more embodiments described herein. [Figure 10]FIG. 1 illustrates a flow diagram of an exemplary, non-limiting method by which the operating frequency of one or more selected Josephson junction resonators (e.g., superconducting qubits) can be modified in accordance with one or more embodiments described herein. [Figure 11] FIG. 1 illustrates a flow diagram of an exemplary, non-limiting method by which the operating frequency of one or more selected Josephson junction resonators (e.g., superconducting qubits) can be modified in accordance with one or more embodiments described herein. [Figure 12] FIG. 1 illustrates a block diagram of an exemplary, non-limiting operating environment in which one or more embodiments described herein may be facilitated. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The following detailed description is merely illustrative and is not intended to limit the embodiments or the application or uses of the embodiments or combinations thereof, nor is it intended to be bound by any expressed or implied information presented in the preceding Background or Summary sections or in the Detailed Description section.

[0017] One or more embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a more thorough understanding of one or more embodiments. However, it will be apparent that in various instances, one or more embodiments may be practiced without these specific details.

[0018] Various embodiments described herein may relate to methods, apparatus, or systems, or combinations thereof, that may chemically modify the electrical resistance of one or more Josephson junctions to change the operating frequency of selected Josephson junction resonators (e.g., superconducting qubits). In one or more embodiments, one or more Josephson junction resonators may be subjected to one or more plasma treatments to change the Josephson junction electrical resistance. In various embodiments, one or more Josephson junction resonators may comprise Josephson junctions that may transition (e.g., have an altered electrical resistance) from a first electrical resistance to a second electrical resistance when a plasma source is applied to the one or more Josephson junctions. For example, the electrical resistance of one or more Josephson junctions may be increased or decreased from an initial resistance value to a target resistance value based on one or more attributes of the plasma treatment. Exemplary attributes that may affect the electrical resistance transition may include, but are not limited to: a treatment time of the plasma treatment, a chemical composition of the plasma treatment, an amount of energy delivered to the Josephson junctions by the plasma treatment, a partial pressure of the plasma gas, a combination thereof, or the like.

[0019] When the electrical resistance of the one or more Josephson junctions transitions, the operating frequency of the one or more Josephson junctions may thereby be altered. For example, an increase in the electrical resistance of the one or more Josephson junctions may be correlated with a decrease in the operating frequency of the one or more Josephson junction resonators. For example, one or more plasma treatments may increase the electrical resistance of the one or more Josephson junctions, thereby lowering the operating frequency of the one or more Josephson junction resonators. In another example, a decrease in the electrical resistance of the one or more Josephson junctions may be correlated with an increase in the operating frequency of the one or more Josephson junction resonators.

[0020] In various embodiments, the plasma treatment(s) may be directed at the target Josephson junction resonators using one or more patterned masks. For example, the patterned mask(s) may shield the one or more Josephson junction resonators from the plasma treatment while exposing the one or more target Josephson junction resonators. In another example, the plasma treatment(s) may be implemented via one or more localized techniques, such as one or more direct write processes.

[0021] In one or more embodiments, the one or more devices and / or systems can further facilitate the frequency tuning method by constraining one or more sliding shields. For example, movement of the one or more sliding shields can be directed with respect to Josephson junction placement on a Josephson junction resonator die (e.g., a qubit die). The sliding shields can include one or more holes for directing application of one or more plasma treatments, where the one or more holes can be aligned with a target Josephson junction resonator by moving the one or more sliding shields.

[0022] 1 illustrates an exemplary, non-limiting diagram of a first stage of a Josephson junction resonator frequency tuning process 100 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. During the first stage of the Josephson junction resonator frequency tuning process 100, one or more target Josephson junction resonators 102 may be identified for operating frequency modification.

[0023] 1, multiple Josephson junction resonators 102 may be included within a Josephson junction resonator die 104. For example, multiple Josephson junction resonators 102 may be disposed on a semiconductor substrate 106. Those skilled in the art will appreciate that the arrangement of Josephson junction resonators 102 on the semiconductor substrate 106 may vary depending on the function and / or type of qubit processor being fabricated.

[0024] The semiconductor substrate 106 may be crystalline, semi-crystalline, microcrystalline, or amorphous. The semiconductor substrate 106 may essentially (e.g., except for contaminants) comprise a single element (e.g., silicon or germanium) or a compound (e.g., aluminum oxide, silicon dioxide, gallium arsenide, silicon carbide, silicon germanium, combinations thereof, or the like, or combinations thereof) or both. The semiconductor substrate 106 may also have multiple layers of material, such as, but not limited to, a semiconductor-on-insulator substrate ("SeOI"), a silicon-on-insulator substrate ("SOI"), a germanium-on-insulator substrate ("GeOI"), a silicon-germanium-on-insulator substrate ("SGOI"), combinations thereof, or the like, or combinations thereof. In addition, the semiconductor substrate 106 may also have other layers, such as an oxide having a high dielectric constant ("high-K oxide") and / or a nitride. In one or more embodiments, the semiconductor substrate 106 can be a silicon wafer. In various embodiments, the semiconductor substrate 106 can include single crystal silicon (Si), silicon germanium (e.g., characterized by the chemical formula SiGe), a III-V semiconductor wafer or surface / active layer, combinations thereof, or the like, or combinations thereof.

[0025] In various embodiments, the Josephson junction resonators 102 may be qubits (e.g., fixed frequency superconducting transmons) or traveling wave or parametric amplifiers using Josephson junction technology, or a combination thereof. For example, one or more of the Josephson junction resonators 102 may comprise one or more capacitors 108 or Josephson junctions 110 or both. Additionally, one or more of the Josephson junction resonators 102 may be interconnected with one another and / or operably coupled to one or more readout devices or circuit elements or both. In one or more embodiments, one or more of the Josephson junction resonators 102 may be fabricated with or without a substrate. Although FIG. 1 illustrates a Josephson junction resonator die 104 (e.g., a qubit die) comprising three exemplary Josephson junction resonators 102, one skilled in the art will appreciate that embodiments including fewer than three Josephson junction resonators 102 or more than three Josephson junction resonators 102 are also contemplated. For example, the Josephson junction resonator die 104 may comprise an array of Josephson junction resonators 102 disposed in various configurations on a semiconductor substrate 106. Additionally, the composition and / or structure of the Josephson junction resonators 102 may vary or may be substantially the same.

[0026] FIG. 1 illustrates an exploded view of one Josephson junction 110 of an exemplary Josephson junction resonator 102. As illustrated in FIG. 1, one or more Josephson junctions 110 may comprise a three-layer structure comprising: a first superconducting metal layer 112, a metal oxide or nitride layer 114, and a second superconducting metal layer 116. As used herein, the term "superconducting" may refer to a characteristic of a material that exhibits superconducting properties below a superconducting critical temperature, such as aluminum (e.g., superconducting critical temperature of 1.2 Kelvin) or niobium (e.g., superconducting critical temperature of 9.3 Kelvin). In addition, one skilled in the art will appreciate that other superconductor materials (e.g., hydride superconductors, e.g., lithium / magnesium hydride alloys) may be used in various embodiments described herein.

[0027] In various embodiments, the first superconducting metal layer 112 and the second superconducting metal layer 116 may have the same, or substantially the same, metal composition. Additionally, the metal oxide or nitride layer 114 may include the metal composition of the first superconducting metal layer 112 and the second superconducting metal layer 116 oxidized or nitrided. Exemplary metals that may comprise the first superconducting metal layer 112 and the second superconducting metal layer 116 may include, but are not limited to, the following: aluminum (Al), niobium (Nb), niobium nitride (NbN), combinations thereof, or the like, or combinations thereof. For example, the first superconducting metal layer 112 and the second superconducting metal layer 116 may include Al, and the metal oxide or nitride layer 114 may include aluminum oxide (AlOx), magnesium oxide (MgO), or aluminum nitride (AlN), or a combination thereof, representing a Josephson junction 110 having an Al / AlOx / Al tri-layer structure. As also shown in FIG. 1, one or more Josephson junctions 110 may be disposed in parallel or series between and / or operably coupled to one or more superconducting capacitors 108 (e.g., including superconducting metals, e.g., Nb, Nb, NbCN, NbTiN, Pb, NbN, TiN, Ta, or the like, or a combination thereof).

[0028] In various embodiments, the one or more Josephson junctions 110 may have an effective critical current in the range of, for example, 10 or more and 100 nanoamperes or less. The critical current may be related to the electrical resistance of the one or more Josephson junctions 110 prior to achieving a superconducting state as described by the Ambegaokar-Baratoff relationship. For example, the electrical resistance of the one or more Josephson junctions 110 prior to achieving a superconducting state may be inversely proportional to the critical current after becoming superconducting. Similarly, the critical current may be inversely proportional to the inductance of the one or more Josephson junctions 110. The resonant frequency of the one or more Josephson junction resonators 102 may thereby range, for example, from hundreds of megahertz or more to 20 gigahertz or less.

[0029] In one or more embodiments, the Josephson junction resonator 102 may be a single junction transmon qubit, thereby being less susceptible to tuning using magnetic fields and having a resonant frequency fixed by the parameters of the capacitor 108 and the Josephson junction 110 formed during fabrication. Additionally, in various embodiments, the Josephson junction resonator 102 may be a phase or charge or both qubit. For example, the Josephson junction resonator 102 may comprise two or more Josephson junctions 110 arranged in series or parallel circuit elements. Furthermore, the Josephson junction 110 may be formed according to various fabrication methods, including, for example, subtractive patterning of a three-layer structure, or a Doran Bridge process.

[0030] Herein, one or more Josephson junctions 110 may be subjected to one or more plasma treatments to alter the electrical resistance of the Josephson junctions 110, thereby altering the operating frequency of the respective Josephson junction resonators 102. Additionally, one or more plasma treatments may be applied to the target Josephson junctions 110 to selectively modify the target Josephson junction resonators 102. As shown in FIG. 1, the initial electrical resistance of one or more Josephson junctions 110 may be measured to identify the Josephson junction resonators 102 for modification. For example, an electrical resistance probe may be used to measure the electrical resistance of a particular Josephson junction 110 and / or Josephson junction resonators 102. For example, FIG. 1 illustrates the use of an exemplary four-prong electrical resistance probe 118 to measure the electrical resistance. In various embodiments, the junction resistance measurements may be an inexpensive proxy for the junction resonator frequency. Additionally, the Josephson junction resonator die 104 may be cooled through the superconducting transition and the resonant frequency may be measured directly by measuring the frequency-dependent device impedance with a network analyzer.

[0031] In various embodiments, the measured electrical resistance and / or resonant frequency may be compared to one or more defined thresholds to determine whether the Josephson junction resonator 102 should be targeted for a subsequent plasma treatment. For example, one or more Josephson junctions 110 and / or Josephson junction resonators 102 may be identified as target Josephson junctions 110 and / or target Josephson junction resonators 102 based on whether the measured electrical resistance is greater than or less than a defined resistance threshold. In one or more embodiments, the measured electrical resistance of a first Josephson junction 110 and / or Josephson junction resonator 102 may be compared to the measured electrical resistance of a second Josephson junction 110 and / or Josephson junction resonator 102. For example, the electrical resistances of adjacent Josephson junctions 110 may be measured and compared to one another to identify one or more Josephson junctions 110 and / or Josephson junction resonators 102 for targeting by one or more plasma treatments.

[0032] 2 illustrates an exemplary, non-limiting diagram of a second stage of the Josephson junction resonator frequency tuning process 100 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. During the second stage of the Josephson junction resonator frequency tuning process 100, one or more masks 202 may be deposited and / or patterned onto the multiple Josephson junction resonators 102.

[0033] In various embodiments, one or more masks 202 may be deposited and / or patterned onto the plurality of Josephson junction resonators 102 based on the measured electrical resistance of the Josephson junctions 110. For example, the one or more masks 202 may cover one or more Josephson junctions 110 of the Josephson junction resonators 102 that are not subject to modification by one or more subsequent plasma treatments while leaving one or more other Josephson junctions 110 of the Josephson junction resonators 102 that are subject to modification exposed. The one or more masks 202 may shield one or more basic Josephson junctions 102 and / or Josephson junctions 110 from the plasma treatments. For example, the one or more masks 202 may prevent one or more reactant species of one or more plasma treatments from interacting with the covered Josephson junction resonators 102 and / or Josephson junctions 110. Exemplary materials that may be included in the one or more masks 202 may include, but are not limited to, the following: stainless steel, Al, steel, copper (Cu), molybdenum (Mo), titanium (Ti), tantalum (Ta), glass, silicon (Si), silicon carbide (SiC), quartz, other metals, combinations thereof, or the like, or combinations thereof.

[0034] As shown in FIG. 2, one or more mask holes 204 may be patterned in the one or more masks 202. The one or more mask holes 204 may be aligned with one or more Josephson junctions 110 targeted for modification based on the measured electrical resistance. Thereby, the one or more target Josephson junctions 110 may remain exposed (e.g., uncovered) despite the presence of the one or more masks 202. In various embodiments, the one or more mask holes 204 may have a polygonal shape (e.g., triangular, rectangular, square, etc.) or a circular shape. In addition, the size of the one or more mask holes 204 may vary based on the size of the one or more target Josephson junctions. Furthermore, the size of the one or more mask holes 204 may account for one or more hole manufacturing tolerances (e.g., dicing tolerances, laser cutting tolerances) or alignment tolerances or a combination thereof. For example, the mask hole(s) 204 may be square holes in the mask(s) 202 and may have dimensions ranging from, for example, 50 micrometers (μm)×50 μm to 500 μm×500 μm.

[0035] In one or more embodiments, the one or more masks 202 may be a hard material (e.g., flat or substantially flat) that may be patterned with one or more mask holes 204 before being placed on the plurality of Josephson junction resonators 102. For example, the one or more mask holes 204 may be engraved into the hard material at locations based on the placement of the Josephson junction resonators 102 on the semiconductor substrate 106. An exemplary cutting process may include, but is not limited to, dicing and / or laser cutting. For example, locations of Josephson junctions 110 included in the Josephson junction resonator die 104 may be mapped on the one or more masks 202. Locations of Josephson junctions 110 of interest may be identified on the mapped mask 202, where material of the mask 202 may be removed from the identified locations to form the mask holes 204. Thereby, when the one or more masks 202 are placed on the Josephson junction resonator die 104, the one or more mask holes 204 can be aligned with one or more Josephson junctions 110 that are subject to exposure to a plasma treatment based on the measured electrical resistance.

[0036] In some embodiments, the mask(s) 202 may be deposited on the Josephson junction resonator(s) 102 via one or more deposition processes. As used herein, the terms “deposition process” and / or “deposition processes” may refer to processes, or combinations thereof, that grow, overlay, deposit, or otherwise transfer one or more first materials onto one or more second materials. Exemplary deposition processes may include, but are not limited to, physical vapor deposition ("PVD"), chemical vapor deposition ("CVD"), electrochemical deposition ("ECD"), atomic layer deposition ("ALD"), low pressure chemical vapor deposition ("LPCVD"), plasma enhanced chemical vapor deposition ("PECVD"), high density plasma chemical vapor deposition ("HDPCVD"), near atmospheric chemical vapor deposition ("SACVD"), rapid thermal chemical vapor deposition ("RTCVD"), in situ radical assisted deposition, high temperature oxide deposition ("HTO"), low temperature oxide deposition ("LTO"), limited reaction processing CVD ("LRPCVD"), ultra-high vacuum chemical vapor deposition ("UHVCVD"), metal organic chemical vapor deposition ("MOCVD"), physical vapor deposition ("PVD"), chemical oxidation, sputtering, plating, evaporation, spin-on coating, ion beam deposition, electron beam deposition, laser assisted deposition, chemical solution deposition, combinations thereof, or the like.

[0037] Additionally, the mask hole(s) 204 may be formed by not depositing the mask(s) 202 at the mask hole(s) 204 location during the deposition process(es). Alternatively, the mask hole(s) 204 may be formed by removing one or more portions of the deposited mask(s) 202 via one or more etching and / or removal processes. As used herein, the terms "etch process", "etch processes", "removal process" or "removal processes" or combinations thereof may refer to any process that removes one or more first materials from one or more second materials. Exemplary etching and / or removal processes may include, but are not limited to, wet etching, dry etching (e.g., reactive ion etching ("RIE")), chemical mechanical planarization ("CMP"), combinations thereof, or the like.

[0038] The one or more masks 202 may have a thickness (e.g., along the y-axis) of, for example, 10 micrometers (μm) or more and 5 millimeters (mm) or less. As shown in FIG. 2, the one or more mask holes 204 may span the entirety, or substantially the entirety, of the thickness of the one or more masks 202. Furthermore, in various embodiments, the one or more mask holes 204 may be directly aligned with the location of the target Josephson junction 110 or may be offset with respect to the location of the target Josephson junction 110. For example, FIG. 2 illustrates an exemplary embodiment in which the mask holes 204 are directly aligned with the target Josephson junction 110 (e.g., the left-most Josephson junction 110). However, embodiments in which the mask holes 204 are only partially aligned with the target Josephson junction 110 (e.g., thereby causing at least a portion of the target Josephson junction 110 to be covered by the one or more masks 202) are also contemplated.

[0039] In various embodiments, the dimensions of the one or more mask holes 204 may depend on the dimensions of the one or more target Josephson junctions 110 and / or the measured electrical resistance of the one or more target Josephson junctions 110. In one or more embodiments, the dimensions of the one or more mask holes 204 may follow one or more defined standards. Further, where one or more masks 202 comprise multiple mask holes 204, the mask holes 204 may have the same dimensions or various dimensions. For example, a first mask hole 204 may be characterized by a first set of dimensions, while a second mask hole 204 may be characterized by a second set of dimensions, where the first and second sets of dimensions may be substantially equivalent or different.

[0040] The dimensions of the one or more mask holes 204 may directly affect the extent of chemical change achieved by one or more subsequent plasma treatments. Thus, the dimensions of the mask holes 204 may be defined based on the amount of resistive transition planned for the target Josephson junctions 110 aligned or partially aligned with the respective mask holes 204. For example, in one or more embodiments, the first mask hole 204 corresponding to the first Josephson junction 110 may be larger than the second mask hole 204 corresponding to the second Josephson junction 110, such that the first Josephson junction 110 may be subject to a greater amount of electrical resistive transition than the second Josephson junction 110. In addition, the extent of chemical change may be further affected by other characteristics of the plasma treatment according to various embodiments described herein (e.g., the type of reactant species used in the plasma treatment, the amount of energy imparted by the plasma treatment, the time the target Josephson junctions 110 are exposed to the plasma treatment, combinations thereof, or the like, or combinations thereof). In one or more embodiments, the mask holes 204 may have uniform dimensions, where a desired degree of chemical transformation may be achieved through manipulation of one or more of the other plasma processing properties.

[0041] 3 illustrates an exemplary, non-limiting diagram of a second stage of the Josephson junction resonator frequency tuning process 100 including one embodiment of one or more masks 202 having one or more electrodes 302 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. As shown in FIG. 3, in various embodiments, the one or more masks 202 may further include one or more electrodes 302 disposed around the periphery of the one or more mask holes 204.

[0042] As shown in FIG. 3, one or more electrodes 302 may be incorporated into one or more masks 202 that surround or at least partially surround one or more mask holes 204. Additionally, embodiments including one or more electrodes 302 disposed on the top of one or more masks 202 that surround or at least partially surround one or more mask holes 204 are also envisioned. The one or more electrodes 302 may have a thickness (e.g., along the y-axis) that is less than, the same as, or greater than the thickness of the one or more masks 202. Exemplary types of electrodes 302 that may be disposed adjacent one or more mask holes 204 may include, but are not limited to: charged plates, magnetic coils, combinations thereof, or the like. In various embodiments, the one or more electrodes 302 may be deposited via one or more deposition processes subsequent to the formation of one or more mask holes 204.

[0043] In various embodiments, the one or more electrodes 302 can generate one or more electric and / or magnetic fields that can modulate the movement of plasma species through the one or more mask holes 204. Current can be supplied to the one or more electrodes 302 to generate an electric and / or magnetic field that can repel one or more plasma process reactant species. Activating the one or more electrodes 302 can thereby generate one or more electric and / or magnetic fields that can protect the corresponding target Josephson junctions 110 from the plasma process even though the target Josephson junctions 110 are exposed by the mask holes 204.

[0044] In one or more embodiments, each electrode 302 may be disposed adjacent to a respective mask hole 204 such that migration of plasma reactant species through the mask hole 204 may be selectively controlled. For example, a first electrode 302 disposed adjacent to a first mask hole 204 may be activated at a different time during plasma treatment than a second electrode 302 disposed adjacent to a second mask hole 204. Thereby, a first Josephson junction 110 aligned with a first mask hole 204 may have a different exposure time to plasma treatment than a second Josephson junction 110 aligned with a second mask hole 204. Thus, the amount of chemical change achieved by plasma treatment may differ between the first Josephson junction 110 and the second Josephson junction 110 based on activation or deactivation of the first and second electrodes 302.

[0045] FIG. 4 illustrates an exemplary, non-limiting diagram of a second stage of the Josephson junction resonator frequency tuning process 100 including one embodiment of one or more masks 202 having multiple layers according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. As shown in FIG. 4, in various embodiments, one or more masks 202 may further comprise one or more layers that can impart various functionality to one or more masks 202. For example, one or more masks 202 may comprise a first layer 402 or a second layer 404 or both. Embodiments are envisioned in which one or more masks 202 comprise a first layer 402, a second layer 404, or both a first layer 402 and a second layer 404 (e.g., as shown in FIG. 4).

[0046] In one or more embodiments, the first layer 402 may include one or more inert materials that do not contaminate the one or more Josephson junction resonators 102. For example, the first layer 402 may be disposed on one or more sides of the mask 202 facing the one or more Josephson junction resonators 102. Furthermore, the first layer 402 may contact the one or more Josephson junction resonators 102 upon deposition and / or placement of the one or more masks 202. In addition, the first layer 402 may include one or more soft and / or elastic materials to avoid physical damage when contacting the one or more Josephson junction resonators 102. Furthermore, the first layer 402 may include one or more materials that can absorb one or more plasma species of one or more plasma processes (e.g., thereby further protecting and / or isolating the Josephson junction resonators 102 adjacent to the one or more target Josephson junctions 110). Exemplary materials that may be included in the first layer 402 may include, but are not limited to, the following: polymers (e.g., polyimide, Teflon), epoxy resins, silicon, metals (e.g., stainless steel, Mo, or the like, or combinations thereof), Ti, Ta, dielectrics (e.g., TiN, SiC, Al 2 O 3 ), combinations thereof, or the like, or combinations thereof. In various embodiments, the first layer 402 can have a thickness (e.g., along the y-axis) of, for example, 100 nanometers (nm) or more and 1 mm or less. In one or more embodiments, the first layer 402 can be disposed across the entire, or substantially the entire, width (e.g., along the x-axis) of the mask 202, or across a portion of the mask 202 width. For example, the first layer 402 can be selectively disposed on portions of the mask 202 aligned with the covered Josephson junction resonators 102.

[0047] In one or more embodiments, the second layer 404 may include one or more materials that may be inert to one or more plasma treatments. For example, the second layer 404 may include one or more materials that remain unreacted during one or more plasma treatments. The second layer 404 may be disposed on one or more sides of the mask 202 facing away from the one or more Josephson junction resonators 102. For example, the second layer 404 may be disposed on one or more sides of the mask 202 that face the one or more plasma treatments. For example, the one or more masks 202 may include both the first layer 402 and the second layer 404, where each layer may be disposed on the opposite surface and / or side of the one or more masks 202. Exemplary materials that may be included within the second layer 404 may include, but are not limited to, the following: stainless steel, Al, steel, Cu, Mo, Ti, Ta, glass, quartz, Si, SiC, other metals, combinations thereof, or the like, or combinations thereof. In various embodiments, the second layer 404 can have a thickness (e.g., along the y-axis) of, for example, 25 μm or more and 10 mm or less. In one or more embodiments, the second layer 404 can be disposed across the entire or substantially the entire width (e.g., along the x-axis) of the mask 202, or across a portion of the mask 202 width.

[0048] 5 shows an exemplary, non-limiting diagram of a third stage of the Josephson junction resonator frequency tuning process 100 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. During the third stage of the Josephson junction resonator frequency tuning process 100, one or more plasma treatments may be implemented.

[0049] In one or more embodiments, the plasma process(es) can discharge the reactant plasma 502 into the one or more masks 202. Additionally, the reactant plasma 502 can flow through one or more mask holes 204 and interact with one or more target Josephson junctions 110. As shown in FIG. 5, the Josephson junctions 110 covered by the one or more masks 202 can be protected from the reactant plasma 502, while the one or more target Josephson junctions 110 not covered by the one or more masks 202 can be exposed to the reactant plasma 502 through the one or more mask holes 204. In various embodiments, all or substantially all of the target Josephson junctions 110 can be chemically altered by the reactant plasma 502 in parallel (e.g., simultaneously). For example, by discharging the reactant plasma 502 into the entirety, or substantially the entirety, of the one or more masks 202, the reactant plasma 502 can access the mask holes 204 in parallel, thereby chemically altering the electrical resistance of the target Josephson junctions 110 in parallel.

[0050] Exemplary forming gases that may be used during the one or more plasma processes and thereby included in the reactant plasma 502 may include, but are not limited to, the following: hydrogen, oxygen, nitrogen, helium (He), methane, ethane, propane, butane, ammonia, hydrogen peroxide, combinations thereof, or the like, or combinations thereof. In one or more embodiments, the one or more plasma processes may be performed at vacuum pressure or atmospheric pressure. In one or more embodiments, the one or more plasma processes may be exposed to the one or more target Josephson junctions 110 for a time period ranging from, for example, 1 second or more and 300 seconds or less. In one or more embodiments, at least one of the one or more plasma processes is a hydrogen plasma process, where the reactant plasma 502 is a hydrogen plasma.

[0051] As used herein, the plasma treatment(s) can chemically alter the electrical resistance of the exposed target Josephson junctions 110. The amount of electrical resistance transition experienced by the target Josephson junctions 110 can depend, for example, on the treatment time of the plasma treatment(s) (e.g., how long the target Josephson junctions 110 are exposed to the plasma treatment(s), the chemical composition of the plasma treatment(s), the amount of energy delivered to the target Josephson junctions 110 by the plasma treatment(s), the partial pressure of the plasma gas, a combination thereof, or the like. In one or more embodiments, the characteristics of the plasma treatment(s) (e.g., reactant composition, plasma frequency, exposure time, or the like, or a combination thereof) can be adjusted to affect the amount of electrical resistance transition achieved.

[0052] In various embodiments, the third stage can include a series of plasma treatments, where each plasma treatment in the series can use a different species of reactant plasma 502. For example, during a first plasma treatment, the reactant plasma 502 can include a hydrogen plasma, where a second plasma treatment can be subsequently used that discharges an oxygen plasma as the reactant plasma 502. Additionally, each plasma treatment in the series of plasma treatments can have one or more of the same characteristics and / or one or more different characteristics (e.g., different reactant compositions, plasma frequencies, exposure times, and the like, or a combination thereof).

[0053] 6 shows an exemplary, non-limiting diagram of a third stage of the Josephson junction resonator frequency tuning process 100, in which one or more plasma treatments are localized according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. During the third stage of the Josephson junction resonator frequency tuning process 100, one or more plasma treatments may be implemented sequentially on localized portions of the Josephson junction resonator die 104 to sequentially modify the target Josephson junctions 110.

[0054] As shown in FIG. 6, the plasma process(es) can be via an atmospheric plasma source 602 that can discharge the reactant plasma 502 by using a plasma source with a narrow beam that is a directional or focused source, where the motion of the plasma gas beam can be further constrained with one or more apertures such that the reactant plasma 502 is a directed narrow beam of gas rather than a cloud. The advantage of the beam is that the mask 202 may not need to be in close proximity to the Josephson junction resonator die 104, but rather just an aperture some way above. The plasma beam source can be moved to be localized in proximity to one or more specific mask holes 204. The entirety of the mask holes 204 can thereby receive the reactant plasma 502 via a series of plasma discharges, where each plasma discharge can be selectively applied to a mask hole 204 in sequence (as opposed to in parallel, for example, as shown in FIG. 5). In one or more embodiments, the plasma process characteristics (e.g., reactant composition, plasma frequency, exposure time, or the like, or a combination thereof) can be different between discharges. Thereby, the degree of electrical resistance transition can be varied between target Josephson junctions 110 by varying the plasma treatment characteristics between successive plasma discharges.

[0055] For example, a plasma treatment may include at least two plasma discharges directed at at least two target Josephson junctions 110. A first plasma discharge of an exemplary plasma treatment may be directed at a first target Josephson junction 110 and may use a first set of characteristics (e.g., reactant composition, plasma frequency, exposure time, or the like, or a combination thereof). However, a second plasma discharge of an exemplary plasma treatment may be directed at a second Josephson junction 110 and may use a second set of characteristics (e.g., reactant composition, plasma frequency, exposure time, or the like, or a combination thereof). Thus, the first target Josephson junction 110 and the second target Josephson junction 110 may experience different amounts of electrical resistance change due at least in part to differences in the two sets of plasma treatment characteristics.

[0056] In one or more embodiments, the mask(s) 202 may be an inert gasket disposed over the Josephson junction resonator(s) 102 under compression to protect some Josephson junctions 110 while exposing the target Josephson junctions 110. For example, the placement of the mask(s) 202 may be limited to a portion of the Josephson junction resonator die 104 that corresponds to a localized discharge proximity of the plasma process, where the mask(s) 202 may be repositioned when the plasma source is subsequently repositioned to remain within the localized discharge proximity. For example, when the atmospheric plasma source 602 is relocated from the location of one exposed Josephson junction 110 to the location of another Josephson junction 110, the mask(s) 202 (e.g., an inert gasket) may be similarly relocated to facilitate the desired guidance of the discharged reactant plasma 502.

[0057] In various embodiments, the electrical resistance of the Josephson junction resonator 102 may be re-measured after one or more plasma treatments, such that if the transferred electrical resistance (e.g., measured after one or more plasma treatments) remains different from the desired electrical resistance, one or more plasma treatments may be repeated to achieve the desired electrical resistance.

[0058] FIG. 7 illustrates a diagram of an exemplary, non-limiting shielding device 700 that can facilitate the Josephson junction resonator frequency tuning process 100 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. As shown in FIG. 7, the shielding device 700 can house the Josephson junction resonator die 104 during the Josephson junction resonator frequency tuning process 100. In addition, the shielding device 700 can control another cover sheet 702 that can further direct the discharge of plasma during one or more plasma processes.

[0059] In various embodiments, the shielding device 700 may include a support platform 704. As shown in FIG. 7, one or more Josephson junction resonator dies 104 may be disposed on at least a portion of the support platform 704. The support platform 704 may thereby provide structural and / or mechanical support to the Josephson junction resonator die 104. Additionally, the support platform 704 may include one or more rigid materials. Exemplary materials that may be included in the support platform 704 may include, but are not limited to: stainless steel, Al, steel, Cu, Mo, Ti, Ta, glass, quartz, Si, SiC, other metals, combinations thereof, or the like, or combinations thereof. Additionally, the shielding device 700 may include a pocket 706 that may accommodate the Josephson junction resonator die 104 when the Josephson junction resonator die 104 is positioned on the support platform 704. For example, the pocket 706 may surround or substantially surround a side of the Josephson junction resonator die 104. In one or more embodiments, the pocket 706 may limit movement of the Josephson junction resonator die 104 on the support platform 704. In some examples, the pocket 706 may be integrally formed with the support platform 704. In other examples, the pocket 706 may be a separate and / or adjustable feature (e.g., the position of the pocket 706 may be adjusted on the support platform 704 depending on the dimensions of the Josephson junction resonator die 104). Exemplary materials that may be included within the pocket 706 may include, but are not limited to, the following: stainless steel, Al, steel, Cu, Mo, Ti, Ta, glass, quartz, Si, SiC, other metals, combinations thereof, or the like, or combinations thereof.

[0060] In one or more embodiments, the one or more masks 202 may be deposited and / or patterned onto the one or more Josephson junction resonators 102 prior to placement of the Josephson junction resonator die 104 on the support platform 705. In various embodiments, the one or more masks 202 may be deposited and / or patterned onto the one or more Josephson junction resonators 102 after placement of the Josephson junction resonator die 104 on the support platform 705. For example, the one or more masks 202 may extend over the pocket 706 (e.g., as shown in FIG. 7 ). The one or more masks 202 may be deposited and / or patterned according to various embodiments described herein.

[0061] As shown in FIG. 7 , one or more slide guides 708 may further be disposed on the pocket 706. For example, the one or more slide guides 708 may be secured to the pocket 706 via one or more fastening devices 709 (e.g., screws, bolts, nails, adhesives, or the like, or a combination thereof). In various embodiments, the one or more slide guides 708 may guide the movement of the one or more cover sheets 702. For example, the cover sheet 702 may move laterally (e.g., along the x-axis shown in FIG. 7 ) relative to the housed Josephson junction resonator die 104. For example, the lateral direction may be in a plane substantially parallel to a surface of the Josephson junction resonator die 104 that includes the one or more Josephson junction resonators 102. Additionally, the cover sheet 702 may include one or more cover sheet holes 710. As the cover sheet 702 moves along the lateral direction (e.g., along the x-axis shown in FIG. 7 ), the one or more cover sheet holes 710 may be aligned or misaligned with the one or more mask holes 204.

[0062] Movement of the cover sheet 702 may be controlled via one or more actuators 712 (e.g., linear or screw-driven, rotary, piezoelectric, pneumatic, hydraulic, combinations thereof, or the like) operably coupled to the one or more cover sheets 702. Additionally, the one or more actuators 712 may be controlled by one or more computing devices 714. The one or more computing devices 714 may include one or more processors (e.g., a central processing unit ("CPU"), microprocessor, or the like, or a combination thereof) capable of executing program instructions for controlling the operation of the one or more actuators 712 and thereby the movement of the cover sheet 702. The one or more computing devices 714 may include one or more computerized devices, which may include, but are not limited to, the following: a personal computer, a desktop computer, a laptop computer, a cellular telephone (e.g., a smart phone), a computerized tablet (e.g., including a processor), a smart watch, a keyboard, a touch screen, a mouse, combinations thereof, or the like, or a combination thereof.

[0063] In various embodiments, the one or more computing devices 714 may be operatively coupled to the one or more actuators 712 via one or more networks 716. The one or more networks 716 may include wired and wireless networks, including, but not limited to, a cellular network, a wide area network (WAN) (e.g., the Internet), or a local area network (LAN). For example, the one or more computing devices 714 may communicate with the one or more actuators 712 (and vice versa) using virtually any desired wired or wireless technology, including, but not limited to, the following: cellular, WAN, Wireless Fidelity (Wi-Fi), Wi-Max, WLAN, Bluetooth technology, combinations thereof, or the like, or any combination thereof.

[0064] One or more plasma processes described herein can discharge a plasma into the cover sheet 702. For example, the one or more plasma processes can discharge a reactant plasma 502 into a side of the cover sheet 702 facing away from the Josephson junction resonator die 104 (e.g., the top side of the cover sheet 702 along the y-axis depicted in FIG. 7). The reactant plasma 502 can then be exposed to the one or more masks 202 through one or more cover sheet holes 710. There, the one or more cover sheet holes 710 can be aligned or partially aligned with the one or more mask holes 204 (e.g., as shown in FIG. 7), and the reactant plasma 502 can be further exposed to the one or more target Josephson junctions 110. As the cover sheet 702 moves laterally (e.g., along the x-axis depicted in FIG. 7), different portions of the one or more masks 202 (e.g., different mask holes 204) can be exposed or covered by the cover sheet 702.

[0065] In various embodiments, the shielding device 700 can allow the target Josephson junction 110 to be continuously exposed to the plasma treatment, even though the plasma treatment is not localized to a particular region. For example, one or more plasma treatments can discharge a reactant plasma 502 into the cover sheet 702, such that fluid communication of the reactant plasma 502 with the mask holes 204 can be established or not by the placement of one or more cover sheet holes 710 controlled by the movement of the cover sheet 702.

[0066] FIG. 8 illustrates an exemplary, non-limiting top view diagram of an exemplary shielding device 700 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. FIG. 8 depicts an exemplary cover sheet hole 710 configuration in which a cover sheet 702 includes a single cover sheet hole 710. As shown in FIG. 8, the cover sheet hole 710 can have dimensions that exceed one or more mask holes 204. In various embodiments, the dimensions of the one or more cover sheet holes 710 can be large enough to encompass multiple mask holes 204 such that the cover sheet hole 710 can expose multiple mask holes 204 simultaneously from a single position. It will be understood by those skilled in the art that the size, configuration, and / or number of the cover sheet holes 710 can vary depending on the size, configuration, and / or number of the mask holes 204. As shown in FIG. 8, at least a portion of the one or more cover sheet holes 710 may be aligned or partially aligned with one or more mask holes 204 depending on the arrangement of the cover sheet 702.

[0067] FIG. 9 illustrates an exemplary, non-limiting top view diagram of an exemplary shielding device 700 according to one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for brevity. FIG. 9 illustrates a cover sheet 702 in a second position compared to the first position depicted in FIG. 8. The cover sheet 702 can move (e.g., controlled by one or more actuators 712 and / or guided by one or more sliding guides 708) along a lateral direction from the first position depicted in FIG. 8 to the second position depicted in FIG. 9.

[0068] For example, in the first cover sheet 702 position depicted in Figure 8, the leftmost Josephson junction 110 may be subject to modification by plasma treatment, while the middle Josephson junction 110 and the rightmost Josephson junction 110 may be shielded from the plasma treatment. In the second cover sheet 702 position depicted in Figure 9, the middle Josephson junction 110 may be subject to modification by plasma treatment, while the leftmost and rightmost Josephson junctions 110 may be shielded from the plasma treatment. A comparison of Figures 8 and 9 may thereby show an example of how target Josephson junctions 110 (e.g., the leftmost and middle Josephson junctions 110) may be successively exposed to plasma treatment by movement of the cover sheet 702 while maintaining shielding of one or more Josephson junctions 110 (e.g., the rightmost Josephson junction 110) that are to remain unaltered by the plasma treatment.

[0069] Various embodiments herein may include a sequence of plasma treatments, where characteristics of the plasma treatment (e.g., reactive composition) may vary between the sequence of plasma discharges. Additionally, the position of the cover sheet 702 along the lateral direction (e.g., along the x-axis) may vary between the sequence of plasma discharges. Additionally, in one or more embodiments, the position of the cover sheet 702 may be controlled to adjust the plasma exposure time experienced by selected Josephson junctions 110, thereby adjusting the amount of electrical resistance transition experienced by selected Josephson junctions 110. For example, the cover sheet 702 may remain in the first position depicted in FIG. 8 for a longer or shorter period of time than in the second position depicted in FIG. 9, whereby the amount of electrical resistance change experienced by the leftmost Josephson junction 110 and the middle Josephson junction 110 may differ while other characteristics of the plasma treatment remain unchanged.

[0070] 10 illustrates a flow diagram of an exemplary, non-limiting method 1000 that can facilitate a Josephson junction resonator frequency tuning process 100 according to various embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for the sake of brevity.

[0071] At 1002, the method 1000 may include chemically altering one or more Josephson junctions 110 of one or more Josephson junction resonators 102 via one or more plasma treatments. For example, an electrical resistance of one or more Josephson junctions 110 may be altered by exposure to one or more reactant plasmas 502 of one or more plasma treatments. For example, one or more Josephson junction resonators 102 may be included in an array of Josephson junction resonators 102 (e.g., disposed on a semiconductor substrate 106 as a Josephson junction resonator die 104). Additionally, chemically altering one or more Josephson junctions 110 may include targeting one or more Josephson junctions based on a measured electrical resistance and / or directing the performance of one or more plasma treatments through one or more patterned masks 202.

[0072] At 1004, the method 1000 may include selectively adjusting the operating frequency of one or more Josephson junction resonators based on attributes of one or more plasma treatments. For example, the chemical change performed at 1002 may be affected at 1004 by controlling one or more attributes of the one or more plasma treatments. Exemplary plasma treatment attributes that may affect the chemical change may include, but are not limited to: a treatment time of the plasma treatment, a chemical composition of the plasma treatment, an amount of energy delivered to the Josephson junctions by the plasma treatment, a partial pressure of the plasma gas, a combination thereof, or the like, or a combination thereof. By varying one or more of the plasma treatment attributes, the amount of electrical resistance modification experienced by one or more Josephson junctions 110 may also be changed, thereby adjusting the operating frequency of selected Josephson junctions 110.

[0073] In various embodiments, the Josephson junctions 110 may be selectively tuned by adjusting the amount of time each Josephson junction 110 is exposed to one or more plasma treatments. Thus, multiple Josephson junctions 110 are tuned and the plasma exposure time may be varied among the Josephson junctions 110, thereby varying the amount of electrical resistance transition. Additionally, in one or more embodiments, the one or more plasma treatments may include a series of plasma discharges, where different Josephson junctions 110 may be targeted by each discharge, or different plasma treatment characteristics may be used by each discharge, or both. For example, the one or more plasma treatments may implement a localized discharge of reactant plasma 502 to chemically alter multiple Josephson junctions 110 in sequence (e.g., one Josephson junction 110 at a time, or a group of Josephson junctions 110 at a time). In another example, multiple Josephson junctions 110 targeted for chemical alteration (e.g., all Josephson junctions 110 targeted for chemical alteration) may be exposed to one or more plasma treatments in parallel (e.g., simultaneously). In one or more embodiments, one or more Josephson junctions 110 may be exposed to a hydrogen plasma discharge followed by an oxygen plasma discharge.

[0074] 11 illustrates a flow diagram of an exemplary, non-limiting method 1100 that can facilitate the Josephson junction resonator frequency tuning process 100 according to various embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein are omitted for the sake of brevity.

[0075] At 1102, the method 1100 may include identifying one or more Josephson junction resonators 102 for tuning based on measured electrical resistances of one or more Josephson junctions 110 of the one or more Josephson junction resonators 102. For example, identifying one or more Josephson junction resonators 102 at 1102 may be performed according to a first stage of the Josephson junction resonator frequency tuning process 100, and according to various embodiments described herein. For example, one or more Josephson junction resonators 102 may be identified for chemical alteration based on having a measured electrical resistance that deviates from a target electrical resistance by more than a defined threshold.

[0076] At 1104, the method 1100 may include depositing one or more mask layers (e.g., mask 202) on the one or more Josephson junction resonators 102, where the mask layer may include one or more holes (e.g., mask hole 204) that may correlate with one or more locations of the one or more Josephson junctions 110. For example, depositing the one or more mask layers at 1104 may be performed according to a second stage of the Josephson junction resonator frequency tuning process 100 and according to various embodiments described herein. As described herein, the one or more mask layers (e.g., mask 202) may leave the identified Josephson junction resonator 102 at least partially exposed while shielding one or more adjacent Josephson junction resonators 102. Furthermore, as described herein, the one or more mask layers may include one or more patterned electrodes 302 (e.g., located adjacent to the one or more holes) or multiple layers (e.g., first layer 402 or second layer 404 or both).

[0077] At 1106, the method 1100 can include chemically altering one or more Josephson junctions 110 of the one or more Josephson junction resonators 102 via one or more plasma treatments, where one or more mask layers can protect the one or more second Josephson junction resonators 102 from the one or more plasma treatments. For example, chemically altering one or more Josephson junctions 110 at 1106 can be performed according to a third stage of the Josephson junction resonator frequency tuning process 100 and according to various embodiments described herein. For example, an electrical resistance of one or more Josephson junctions 110 can be altered by exposure to one or more reactant plasmas 502 of the one or more plasma treatments. For example, the one or more Josephson junction resonators 102 can be included in an array of Josephson junction resonators 102 (e.g., disposed on a semiconductor substrate 106 as a Josephson junction resonator die 104). Additionally, the chemical change may be a modification to the electrical resistance of one or more Josephson junctions 110 and may be affected by controlling one or more attributes of one or more plasma treatments. Exemplary plasma treatment attributes that may affect the chemical change may include, but are not limited to: the treatment time of the plasma treatment, the chemical composition of the plasma treatment, the amount of energy delivered to the Josephson junctions by the plasma treatment, combinations thereof, or the like. By varying one or more of the plasma treatment attributes, the amount of electrical resistance modification experienced by one or more Josephson junctions 110 may also be varied, thereby adjusting the operating frequency of selected Josephson junctions 110.

[0078] In various embodiments, the Josephson junctions 110 may be selectively tuned by adjusting the amount of time each Josephson junction 110 is exposed to one or more plasma treatments. Thus, multiple Josephson junctions 110 are tuned and the plasma exposure time may be varied among the Josephson junctions 110, thereby varying the amount of electrical resistance transition. Additionally, in one or more embodiments, the one or more plasma treatments may include a series of plasma discharges, where different Josephson junctions 110 may be targeted by each discharge, or different plasma treatment characteristics may be used by each discharge, or both. For example, the one or more plasma treatments may implement a localized discharge of reactant plasma 502 to chemically alter multiple Josephson junctions 110 in sequence (e.g., one Josephson junction 110 at a time, or a group of Josephson junctions 110 at a time). In another example, multiple Josephson junctions 110 targeted for chemical alteration (e.g., all Josephson junctions 110 targeted for chemical alteration) may be exposed to one or more plasma treatments in parallel (e.g., simultaneously). In one or more embodiments, one or more Josephson junctions 110 may be exposed to a hydrogen plasma discharge followed by an oxygen plasma discharge.

[0079] At 1108, the method 1100 may include measuring an electrical resistance of the chemically altered one or more Josephson junctions 110. For example, measuring at 1108 may also be performed according to a first stage of the Josephson junction resonator frequency tuning process 100 and according to various embodiments described herein. At 1110, the method 1100 may proceed based on whether the measured electrical resistance is equal to or substantially equal to a target electrical resistance. For example, the method 1100 may include, at 1102, determining whether the electrical resistance achieved via the plasma treatment deviates from the target electrical resistance by more than a defined threshold used to identify one or more Josephson junction resonators 102. If the measured electrical resistance is substantially equal to the target electrical resistance (e.g., the electrical resistance deviation is less than a defined threshold), the measured Josephson junction resonator 102 may be considered tuned to a desired operating frequency, and the method 1100 may end. If the measured electrical resistance is not substantially equal to the target electrical resistance (e.g., the electrical resistance deviation is greater than a defined threshold), method 1100 can repeat steps 1106-1110 until the target electrical resistance is achieved.

[0080] To provide additional context for the various embodiments described herein, FIG. 12 and the following discussion provide a general overview of a suitable computing environment 1200 in which various embodiments of the embodiments described herein may be implemented. For example, one or more computing devices 714 described herein may use the computing environment 1200 to execute one or more program instructions that may control the operation of one or more actuators 712 and the cover sheet 702. Although the embodiments are described above in the general context of computer-executable instructions that may be executed by one or more computers, those skilled in the art will appreciate that the embodiments may also be implemented in combination with other program modules, or as a combination of hardware and software, or both.

[0081] Generally, program modules include routines, programs, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Furthermore, those skilled in the art will appreciate that the methods of the invention may be practiced with other computer system configurations, including single-processor or multi-processor computer systems, minicomputers, mainframe computers, Internet of Things ("IoT") devices, distributed computing systems, as well as personal computers, handheld computing devices, microprocessor-based or programmable consumer electronics, and the like, each of which may be operatively coupled to one or more associated devices.

[0082] The illustrated embodiments of the embodiments herein may be practiced in a distributed computing environment where certain tasks are performed by remote processing devices linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices. For example, in one or more embodiments, computer-executable components may be executed from a memory that may include or consist of one or more distributed memory units. As used herein, the terms "memory" and "memory unit" are interchangeable. Furthermore, one or more embodiments described herein may execute code of computer-executable components in a distributed manner, e.g., multiple processors cooperatively coupled or operating to execute code from one or more distributed memory units. As used herein, the term "memory" may encompass a single memory or memory unit in one location or multiple memories or memory units in one or more locations.

[0083] A computing device typically includes various media, which may include computer-readable storage media, machine-readable storage media, or communication media, or a combination thereof, and the two terms are used differently from each other herein as follows. A computer-readable storage medium or machine-readable storage medium may be any available storage medium that can be accessed by a computer, and includes both volatile and non-volatile media, removable and non-removable media. By way of example and not limitation, a computer-readable storage medium or machine-readable storage medium may be implemented in association with any method or technology for storage of information, such as computer-readable or machine-readable instructions, program modules, structured or unstructured data, etc.

[0084] A computer-readable storage medium may include, but is not limited to, random access memory ("RAM"), read-only memory ("ROM"), electrically erasable programmable read-only memory ("EEPROM"), flash memory or other memory technology, compact disk read-only memory ("CD-ROM"), digital versatile disk ("DVD"), Blu-ray disk ("BD") or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, solid state drives or other solid state storage devices, or other tangible or non-transitory medium that may be used to store the desired information, or combinations thereof. In this regard, the terms "tangible" or "non-transitory" as applied to storage, memory or computer-readable medium herein should be understood as qualifiers to exclude merely conveying only a transitory signal per se, and does not waive any right to all standard storage, memory or computer-readable media that do not convey only a transitory signal per se.

[0085] A computer-readable storage medium may be accessed by one or more local or remote computing devices for various operations with respect to the information stored by the medium, e.g., via an access request, query or other data retrieval protocol.

[0086] Communication media typically embodies computer-readable instructions, data structures, program modules or other structured or unstructured data in a data signal, such as a modulated data signal, e.g., a carrier wave or other transport mechanism, and includes any information delivery or transport media. The term "modulated data signal" or signal refers to a signal that has one or more of its characteristics set or changed in such a manner as to encode information in one or more signals. By way of example, and not limitation, communication media includes wired media, e.g., a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media.

[0087] Referring again to FIG. 12, an exemplary environment 1200 for implementing various embodiments of the aspects described herein includes a computer 1202 including a processing unit 1204, a system memory 1206, and a system bus 1208. The system bus 1208 couples system components including, but not limited to, the system memory 1206 to the processing unit 1204. The processing unit 1204 can be any of a variety of commercially available processors. Dual microprocessors and other multi-processor architectures can also be used as the processing unit 1204.

[0088] The system bus 1208 may be any of several types of bus structures that may be further interconnected to a memory bus (with or without a memory controller), a peripheral bus, and a local bus using any of a variety of commercially available bus architectures. The system memory 1206 includes a ROM 1210 and a RAM 1212. A basic input / output system ("BIOS") may be stored in non-volatile memory, such as a ROM, erasable programmable read-only memory ("EPROM"), EEPROM, etc., and the BIOS contains basic routines that help to transfer information between elements within the computer 1202, for example, during start-up. The RAM 1212 may also include a high-speed RAM, such as a static RAM, for caching data.

[0089] The computer 1202 further includes an internal hard disk drive ("HDD") 1214 (e.g., EIDE, SATA), one or more external storage devices 1216 (e.g., a magnetic floppy disk drive ("FDD") 1216, a memory stick or flash drive reader, a memory card reader, etc.), and an optical disk drive 1220 (e.g., capable of reading from or writing to CD-ROM disks, DVDs, BDs, etc.). Although the internal HDD 1214 is shown as being located within the computer 1202, the internal HDD 1214 may also be configured for external use in a suitable chassis (not shown). Additionally, although not shown in the environment 1200, a solid state drive ("SSD") may be used in addition to or in place of the HDD 1214. The HDD 1214, external storage device 1216, and optical disk drive 1220 may be connected to the system bus 1208 by an HDD interface 1224, an external storage interface 1226, and an optical drive interface 1228, respectively. The interface 1224 of external drive implementations may include at least one or both of Universal Serial Bus ("USB") and Institute of Electrical and Electronics Engineers ("IEEE") 1394 interface technologies. Other external drive connection technologies are within the contemplation of the embodiments described herein.

[0090] The drives and their associated computer-readable storage media provide non-volatile storage of data, data structures, computer-executable instructions, and the like. For the computer 1202, the drives and storage media provide for the storage of any data in a suitable digital format. Although the foregoing description of computer-readable storage media refers to each type of storage device, those skilled in the art should understand that other types of storage media that are readable by a computer, whether currently existing or developed in the future, may also be used in the exemplary operating environment, and further, that any such storage media may include computer-executable instructions for performing the methods described herein.

[0091] A number of program modules may be stored in the drives and RAM 1212, including an operating system 1230, one or more application programs 1232, other program modules 1234 and program data 1236. All or portions of the operating system, applications, modules, and / or data may also be cached in RAM 1212. The systems and methods described herein may be implemented using various commercially available operating systems or combinations of operating systems.

[0092] The computer 1202 may optionally include emulation technology. For example, a hypervisor (not shown) or other intermediary may emulate the hardware environment of the operating system 1230, and the emulated hardware may optionally differ from the hardware depicted in FIG. 12. In one such embodiment, the operating system 1230 may include one of a number of virtual machines ("VMs") hosted on the computer 1202. Additionally, the operating system 1230 may provide a runtime environment for the application 1232, e.g., a Java runtime environment or a .NET framework. The runtime environment is a consistent execution environment that allows the application 1232 to run on any operating system that includes the runtime environment. Similarly, the operating system 1230 may support containers, and the application 1232 may be in the form of a container, which is a lightweight, standalone, executable package of software that includes, for example, code, runtime, system tools, system libraries, and the application's settings.

[0093] Additionally, computer 1202 may be enabled with a security module, such as a Trusted Processing Module ("TPM"). For example, with a TPM, boot components may then hash at time boot components and wait for a match of the result to a secure value before loading the next boot component. This process can occur at any layer within the code execution stack of computer 1202, for example, applied at the application execution level or at the operating system ("OS") kernel level, thereby enabling security at any level of code execution.

[0094] A user may enter commands and information into the computer 1202 via one or more wired / wireless input devices, such as a keyboard 1238, a touch screen 1240, and a pointing device, such as a mouse 1242. Other input devices (not shown) may include a microphone, an infrared ("IR") remote control, a radio frequency ("RF") remote control, or other remote control, a joystick, a virtual reality controller and / or virtual reality headset, a game pad, a stylus pen, an image input device, such as a camera, a gesture sensor input device, a vision movement sensor input device, an emotion or face detection device, a biometric input device, such as a fingerprint or iris scanner, or the like. These and other input devices are often connected to the processing unit 1204 via an input device interface 1244 that may be coupled to the system bus 1208, but may also be connected by other interfaces, such as a parallel port, an IEEE 1394 serial port, a game port, a USB port, an IR interface, a BLUETOOTH® interface, etc.

[0095] A monitor 1246 or other type of display device may also be connected to the system bus 1208 via an interface, such as a video adapter 1248. In addition to the monitor 1246, a computer typically includes other peripheral output devices (not shown), such as speakers, printers, etc.

[0096] The computer 1202 can operate in a networked environment using logical connections via wired and / or wireless communications to one or more remote computers, e.g., remote computer 1250. The remote computer 1250 can be a workstation, a server computer, a router, a personal computer, a portable computer, a microprocessor-based entertainment device, a peer device or other common network node, and typically includes many or all of the elements described in connection with the computer 1202, although only a memory / storage device 1252 is shown for simplicity. The depicted logical connections include wired / wireless connectivity to a local area network ("LAN") 1254 or a larger network, e.g., a wide area network ("WAN") 1256, or both. Such LAN and WAN networking environments are commonplace in offices and businesses, facilitating enterprise-wide computer networks, e.g., intranets, all of which can connect to a global communications network, e.g., the Internet.

[0097] When used in a LAN networking environment, the computer 1202 may be connected to the local network 1254 via a wired and / or wireless communication network interface or adapter 1258. The adapter 1258 may facilitate wired or wireless communication to the LAN 1254, which may also include a wireless access point ("AP") disposed thereon for communicating with the adapter 1258 in a wireless mode.

[0098] When used in a WAN networking environment, the computer 1202 may include a modem 1260 or be connected via other means for establishing communications over the WAN 1256, e.g., via the Internet, to a communications server on the WAN 1256. The modem 1260, which may be internal or external and a wired or wireless device, may be connected to the system bus 1208 via the input device interface 1244. In a networked environment, program modules depicted relative to the computer 1202, or portions thereof, may be stored in the remote memory / storage device 1252. It will be appreciated that the network connections shown are examples and other means of establishing a communications link between the computers may be used.

[0099] When used in either a LAN or WAN network environment, the computer 1202 can access a cloud storage system or other network-based storage system in addition to or instead of the external storage device 1216 as described above. In general, the connection between the computer 1202 and the cloud storage system can be established via the LAN 1254 or WAN 1256, respectively, by, for example, an adapter 1258 or a modem 1260. When the computer 1202 is connected to an associated cloud storage system, the external storage interface 1226 can manage the storage provided by the cloud storage system as with other types of external storage, using the adapter 1258 or the modem 1260, or both. For example, the external storage interface 1226 can be configured to provide access to cloud storage sources as if those sources were physically connected to the computer 1202.

[0100] The computer 1202 may be operable to communicate with any wireless device or entity operatively arranged for wireless communication, such as printers, scanners, desktop and / or portable computers, personal digital assistants, communications satellites, any equipment or location associated with a wirelessly detectable tag (e.g., a kiosk, newsstand, shelf, etc.), and telephones. This may include Wireless Fidelity ("Wi-Fi") and BLUETOOTH® wireless technologies. Thus, communication may be of a predefined structure, such as a traditional network or simply ad-hoc communication between at least two devices.

[0101] The foregoing includes merely examples of systems, computer program products, and computer-implemented methods. It is of course not possible to describe every conceivable combination of components, products, or computer-implemented methods or combinations thereof for purposes of describing the present disclosure, but those skilled in the art will appreciate that numerous further combinations and permutations of the present disclosure are possible. Furthermore, to the extent that "comprises," "has," "possess," and similar terms are used in the detailed description, claims, appendices, and drawings, such terms are intended to be inclusive in a manner similar to the term "comprises," as "comprises" is interpreted when used as a transitional word in the claims. The description of the various embodiments is presented for purposes of illustration, but is not intended to be exhaustive or limited to the disclosed embodiments. Numerous modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been selected to best explain the principles of the embodiments, practical applications, or technical improvements of the technology found in the marketplace, or to enable those skilled in the art to understand the embodiments disclosed herein.

Claims

1. Selecting a target Josephson junction resonator from among a plurality of Josephson junction resonators; chemically modifying a Josephson junction of the target Josephson junction resonator via plasma treatment; Selectively adjusting an operating frequency of the target Josephson junction resonator based on an attribute of the plasma treatment. A method comprising:

2. 2. The method of claim 1, wherein the attribute is at least one member selected from the group consisting of a treatment time of the plasma treatment, a chemical composition of the plasma treatment, an amount of energy delivered to the Josephson junction by the plasma treatment, and a partial pressure of a gas used by the plasma treatment.

3. 3. The method of claim 1, wherein the plasma treatment comprises exposing the Josephson junction to a series of plasmas, the plasma treatment modifying the electrical resistance of the Josephson junction.

4. localizing the plasma treatment in proximity to the Josephson junction via a plasma beam. The method of any one of claims 1 to 3, further comprising:

5. depositing a mask layer over the Josephson junction resonator; chemically modifying a Josephson junction of the Josephson junction resonator via plasma treatment; Selectively adjusting an operating frequency of the Josephson junction resonator based on an attribute of the plasma treatment. Including, the mask layer includes holes that correlate with the locations of the Josephson junctions; the mask layer protects the second Josephson junction from the plasma treatment; method.

6. 6. The method of claim 5, wherein the mask layer includes a first surface facing the Josephson junction and a second surface facing the plasma treatment, the first surface being characterized by a chemical composition that absorbs plasma species of the plasma treatment and the second surface being characterized by another chemical composition that is inert to the plasma treatment.

7. patterning an electrode on a periphery of the hole in the mask layer; controlling transport of reactive species of the plasma process across the mask layer via operation of the electrodes; The method of any of claims 5 to 6, further comprising:

8. placing an inert gasket over the Josephson junction resonator; chemically modifying a Josephson junction of the Josephson junction resonator via plasma treatment; Selectively adjusting an operating frequency of the Josephson junction resonator based on an attribute of the plasma treatment. Including, the inert gasket includes holes that correlate with the locations of the Josephson junctions; and the inert gasket insulates a second Josephson junction adjacent to the Josephson junction from the plasma treatment. method. selecting a target Josephson junction resonator from among a plurality of Josephson junction resonators; chemically modifying a Josephson junction of the target Josephson junction resonator via plasma treatment; adjusting the electrical resistance of the Josephson junction based on an attribute of the plasma treatment; and A method comprising:

10. 10. The method of claim 9, wherein the plasma treatment exposes the Josephson junction to a series of plasmas, the plasma treatment alters the electrical resistance of the Josephson junction, and the attribute is at least one member selected from the group consisting of a treatment time of the plasma treatment, a chemical composition of the plasma treatment, an amount of energy delivered to the Josephson junction by the plasma treatment, and a partial pressure of a gas used by the plasma treatment.

11. localizing the plasma treatment in proximity to the Josephson junction via a plasma beam. The method of any of claims 9 to 10, further comprising:

12. depositing a mask layer over the Josephson junction resonator; chemically modifying a Josephson junction of the Josephson junction resonator via plasma treatment; adjusting the electrical resistance of the Josephson junction based on an attribute of the plasma treatment; and Including, the mask layer includes holes that correlate with the locations of the Josephson junctions; and the mask layer protects a portion of the Josephson junction resonator from the plasma treatment; method.

13. 13. The method of claim 12, wherein the mask layer includes a first surface facing the Josephson junction resonator and a second surface facing the plasma treatment, the first surface being characterized by a chemical composition that absorbs plasma species of the plasma treatment, and the second surface being characterized by another chemical composition that is inert to the plasma treatment.

14. placing an inert gasket over the Josephson junction resonator; chemically modifying a Josephson junction of the Josephson junction resonator via plasma treatment; adjusting the electrical resistance of the Josephson junction based on an attribute of the plasma treatment; and Including, the inert gasket includes holes that correlate with the locations of the Josephson junctions; and the inert gasket insulates a second Josephson junction adjacent to the Josephson junction from the plasma treatment. method. selecting a target Josephson junction resonator from among a plurality of Josephson junction resonators; exposing the Josephson junctions of said target Josephson junction resonator to a plasma treatment. Including, the plasma treatment adjusts the operating frequency of the Josephson junction resonator to a target operating frequency by modifying the electrical resistance of the Josephson junction. method.

16. The method of claim 15 , wherein the plasma treatment exposes the Josephson junction to a series of plasmas.

17. A method of manufacturing a Josephson junction resonator comprising: exposing a Josephson junction of the Josephson junction resonator to a plasma treatment; Shielding the second Josephson junction from said plasma treatment. Including, the plasma treatment adjusts an operating frequency of the Josephson junction resonator to a target operating frequency by modifying an electrical resistance of the Josephson junction; the second Josephson junction is adjacent to the Josephson junction of the Josephson junction resonator; method.

18. localizing the plasma treatment in proximity to the Josephson junction via a plasma beam.

18. The method of any of claims 15 to 17, further comprising:

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