Pulsed power supply for a compact system for direct coupling of radio

Abstract

A system and related methods are described. The system includes a controlled power source for generating electrical pulses for a plasma discharge source. The controlled power supply includes an output pulse track, a DC power supply, and a storage capacitor coupled to the DC power supply. The storage capacitor is configured to supply a primary negative rail voltage, a positive kick rail voltage, and at least one intermediate rail voltage. The set of controlled pulse power transistors includes a plurality of transistors interposed between the energy storage capacitor and the output pulse track, and a transfer controller configured to control power transfer. The transfer controller is configured to specify a positive kick pulse waveform defined by parameters specified by a user that configure operation of the plurality of transistors to control timing and voltage of the positive kick track voltage and the at least one intermediate track voltage.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a non-provisional application of U.S. Provisional Application No. 63 / 338,090, filed on May 4, 2022, entitled “IMPULSE POWER SUPPLY FOR COMPACT SYSTEM FOR COUPLING RADIO FREQUENCY POWER DIRECTLY INTO RADIO FREQUENCYLINACS,” and claims priority to that application, the entire contents of which (including any references contained therein) are expressly incorporated by reference.

[0003] This application is related to U.S. application serial number 15 / 803,320 (USP 10,624,199), entitled “A COMPACT SYSTEM FOR COUPLING RF POWER DIRECTLY INTO RF LINACS,” filed on November 3, 2017, which is a non-provisional application of U.S. provisional application serial number 62 / 416,900, entitled “A COMPACT SYSTEM FOR COUPLING RF POWER DIRECTLY INTO RF LINACS,” filed on November 3, 2016, the entire contents of each of these applications (including any references therein) are expressly incorporated herein by reference.

[0004] This application is related to U.S. application serial number 16 / 006,357, filed on June 12, 2018, entitled “PULSED POWER MODULE WITH PULSE AND ION FLUX CONTROL FOR MAGNETRON SPUTTERING,” which is a non-provisional application of U.S. provisional application serial number 62 / 518,362, filed on June 12, 2017, entitled “PULSED POWER MODULE WITH PULSE AND ION FLUX CONTROL FOR MAGNETRON SPUTTERING,” the entire contents of each of these applications (including any references therein) are expressly incorporated herein by reference.

[0005] This application is related to U.S. patent application serial number 16 / 801,002, filed on February 25, 2020, entitled “METHOD AND APPARTUS FOR METAL AND CERAMIC NANOLAYERING FOR ACCIDENT TOLERANT NUCLEAR FUEL, PARTICLE ACCELERATORS & AEROSPACE LEADING EDGES,” which is a non-provisional application of U.S. provisional patent application No. 62 / 810,230, filed on February 25, 2019, entitled “METHOD AND APPARATUS FOR METAL AND CERAMIC NANOLAYERING FOR ACCIDENT TOLERANT NUCLEAR FUEL,” the entire contents of each of these applications (including any references therein) are expressly incorporated herein by reference. Technical Field

[0006] The present invention relates generally to injecting power into accelerator devices and, more particularly, to relatively compact high power radio frequency linear accelerator (RF LINAC) systems. Background Art

[0007] High-power RF cavities, such as those in RF LINACs, require not only enormous RF powers (on the order of tens to hundreds of kilowatts and above), but also a vacuum environment to prevent arcing and sparking within the RF cavity due to the strong electric fields associated with such high powers. The RF power required to achieve a specific electric field within the resonant cavity is determined by the quality factor (Q), which is the integrated energy stored divided by the energy lost per cycle. For a resonant RF cavity, the formula simplifies to Because RF energy propagates along the surface, and the surface resistance The surface resistance is a function of the RF frequency, which is proportional to the square root of the RF frequency. Higher quality factors lead to higher efficiency, higher achievable voltages, and accelerating gradients. However, there are engineering tradeoffs in cavity design and operation because the electrical skin depth at GHz frequencies is on the order of microns. RF cavities are typically plated with copper to reduce the surface resistance, or constructed from a solid substrate block for room temperature cavities.

[0008] Typically, RF power is coupled into a high power RF cavity via a waveguide and a sealed RF window. This approach, while feasible in high power LINAC applications, requires additional hardware, which increases the cost, size and complexity of a compact high power RF LINAC system. An alternative to the above approach is to couple RF power directly into the RF cavity via an RF amplifier assembly mounted on the RF cavity, and the output stage is directly coupled to the RF cavity. This approach is described in U.S. Patent 5,084,682 to Swenson. However, due to processes such as multiple factors, containing the entire vacuum tube (and its associated tuning elements) within a vacuum envelope makes it impossible to operate at high power. Therefore, the RF and bias circuits need to be at atmospheric pressure as much as possible. In addition to this constraint, if these structures are not actively cooled, the structures described in Swenson will also have problems due to the high power dissipation in the antenna and vacuum tube anode. Swenson's method of installing an RF amplifier in a high power RF LINAC is further complicated by the fact that the vacuum tube anode is usually maintained at a high voltage, which requires careful selection of a coolant.

[0009] Furthermore, in a high power pulsed magnetron sputtering (HiPIMS) arrangement, high current pulses are applied to a magnetron target, which results in intense sputtering and the formation of a target material rich plasma environment characterized by a high ionization fraction of neutral species relative to the sputtered target material particles. In some HiPIMS pulse arrangements, the sputtering gas (e.g., argon) is diluted and displaced into a self-sputtering regime as the sputtered target material (metal) exceeds the local gas density. During HiPIMS, achieving high ionization fractions with a dominant metal plasma can facilitate novel material deposition mechanisms and process conditions that are not achievable by thermal sputtering.

[0010] As further background, in a HiPIMS arrangement, the sputtered metal ions are positioned near a sputtering target within a magnetic confinement region (magnetic trap). Application of a rapid voltage reversal (e.g., a positive kick) to the target electrode generates a transient voltage drop across the magnetic trap and accelerates the ions away from the target electrode, for example toward a substrate to be coated or treated. This voltage drop is called the short kick phase and typically occurs within the first 20 microseconds after application of the rapid voltage reversal. During the long kick phase, the dense plasma diffuses toward the substrate, resulting in the generation of a local sheath potential along the surface and further accelerating the gas and metal ions onto the substrate. The present disclosure provides improvements to the above aspects of known HiPIMS operation. Summary of the invention

[0011] A system is disclosed that includes a controlled power supply for generating electrical pulses for a plasma discharge source. The controlled power supply includes an output pulse rail, a DC power supply, and a storage capacitor coupled to the DC power supply. The storage capacitor is configured to supply the following via corresponding power rails: a main negative rail voltage, a positive kick rail voltage, and at least one intermediate rail voltage with a voltage amplitude between the main negative rail voltage and the positive kick rail voltage. The system also includes a controlled pulse power transistor group that includes: a plurality of transistors inserted between the storage capacitor and the output pulse rail, and a transmission controller configured to control power transmission from the storage capacitor to the output pulse rail. The transmission controller is configured to specify a positive kick pulse waveform based on a user-specified input. The positive kick pulse waveform is defined by user-specified parameters that configure the operation of the plurality of transistors to control the timing and voltage of the following: the positive kick rail voltage; and at least one intermediate rail voltage.

[0012] The present disclosure also relates to a method of operating the above-mentioned system to perform output power generation according to a user-specified positive kick pulse waveform using the system disclosed herein.

[0013] Other features and advantages of the present invention will become apparent from the following detailed description of illustrative examples with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] While the appended claims set forth the features of the present invention with particularity, the present invention and its objects and advantages will be best understood from the following detailed description taken in conjunction with the accompanying drawings:

[0015] Figure 1 is a schematic diagram of a system suitable for incorporating features of the present invention;

[0016] Figure 2A Depicted Figure 1 A cross-sectional view of the enclosed circuit breaker subassembly elements of the system schematically depicted in FIG, including an RF antenna, a socket interface, and a vacuum flange terminal;

[0017] Figure 2B An illustrative RF power amplifier is depicted, which is, for example, a compact planar triode structure;

[0018] Figure 2C Depicted Figure 2A and Figure 2B The subcomponents in are arranged as Figure 1 A power amplifier component of an RF LINAC system schematically depicted in;

[0019] Figure 3 Depicted is a cross-sectional view of an RF LINAC system comprising four power amplifier assemblies (eg, Figure 2C depicted);

[0020] Figure 4 Schematically depicts an example of Figure 2C Equivalent circuit diagram / model of the power amplifier components depicted in operation;

[0021] Figure 5A is a photo of the exterior of the RF LINAC cavity used in the radio frequency quadrupole accelerator;

[0022] Figure 5B is a photograph of the interior quadrant of the RF cavity formed by the rigid attachment of four blade structures prior to surface modification and formation of a continuous RF seal;

[0023] Figure 5C is a prior art showing a primary-secondary blade configuration for RFQ with alignment gaskets and RF seals at each interface;

[0024] Fig. 6A depicts a cross-sectional view of an illustrative example of surface modification, etching, and deposition of a thin film on a cavity;

[0025] Figure 6B yes Fig. 6A An example of a photograph of an operation in which highly conductive copper is deposited directly onto a mechanical RF seal is shown;

[0026] Figure 6C A composite RF LINAC cavity composed of one or more bulk substrate materials having one or more material coatings is depicted;

[0027] Figure 6C A composite RF LINAC cavity composed of one or more bulk substrate materials having one or more material coatings is depicted;

[0028] Fig.6D An in-situ sputtering electrode that emits ions and neutral particles to coat one or more substrates is depicted;

[0029] Fig. 6E Depicted is a close-up view of a composite RF LINAC cavity, where the blade material is rigidly fixed to the vacuum enclosure via a mechanical / thermal interface, and a thin film continuous coating serves as the electrical interface;

[0030] Fig. 7A An axial internal view of a sputtering electrode emitting ions and neutrals is depicted to highlight the internal coolant flow, magnetic components, and external plasma generation;

[0031] Figure 7B A cross-sectional view of a sputtering electrode is depicted to highlight the relative rotation of the target material and the magnetic assembly;

[0032] Figure 7C is a photograph of an illustrative example of a 1.5 meter long sputtering electrode, wherein a magnetic field is arranged to produce a single serpentine dense plasma region around the sputtering electrode;

[0033] Fig.7D It is used for cleaning, etching and surface modification +Super Kick TM photos of illustrative examples;

[0034] Fig. 7E It is used for injection, mixing, adhesion, stress control, morphology control, diffusion barrier and coating +Positive Kick TM A photograph of an embodiment of the invention;

[0035] Figure 7F is a photograph of an example of a sputtering electrode having a diameter of 6.3 mm, wherein the magnetic field is arranged to produce a plurality of dense plasma regions around the sputtering electrode that can be axially translated;

[0036] Fig. 8A Depicts conformal coating for substrates +Positive Kick TM pictorial diagram;

[0037] Figure 8B is a photo of the coaxial cylindrical magnetron technology, which has PositiveKick TM and Super Kick TM For conformal thin-film copper coatings to replace conventional electroplating and wet electrochemistry on stainless steel cryogenic accelerator bellows;

[0038] Fig.9A A diagram depicting erosion and wear of a sputtering target with narrow V-grooves;

[0039] Fig. 9B depicts a diagram of sputtering target erosion where there is relative motion between the dense plasma region and the sputtering target material for uniform erosion;

[0040] Fig.10 Depicts conventional DC sputtering, pulsed DC, conventional HiPIMS, and +Positive Kick TM Comparison between;

[0041] Fig.11 Illustration depicting the first of three phases during IMPULSE pulse operation – the ultrafast HiPIMS phase;

[0042] Fig.12 Diagram depicting the second of the three phases during the IMPULSE maneuver - the short kick phase;

[0043] Fig.13 A diagram depicting the 3rd of 3 phases during the IMPULSE operation - the long kick phase;

[0044] Fig.14 Depicted for use without breaking vacuum, interruption or segmentation +PositiveKick TM +Super Kick TM A diagram of a continuous process;

[0045] Fig.15 is an oscilloscope waveform of a copper sputtering plasma reaching a 2kA peak current in 20 microseconds during the ultrafast HiPIMS phase, followed by a +200V positive pulse showing the short kick and long kick phases;

[0046] Fig.16 It highlights the use of Positive Kick TM and Super Kick TM Photographs of examples of deposition and etching;

[0047] Fig.17A is an oscilloscope trace showing ~10-100 kHz quasi-RF modulation of a positive pulse to generate a plasma with a positive RF bias;

[0048] Fig. 17B It's Super Kick TM Photographs for plasma generation in etching mode;

[0049] Fig.18 Describes the Schematic diagram of the thin film deposition, etching and surface modification system with pulse modules and power supplies;

[0050] Fig.19 is a graphical representation of a structural area diagram with two independent axes representing the effective temperature T* and the effective sputtered particle energy E*, which can be used and Positive Kick TM To address;

[0051] Fig. 20A yes Photos of the 2-2 system;

[0052] Fig. 20B yes Photos of the 20-20 system;

[0053] Fig.21A It is the existing technology for electroplated stainless steel cryogenic bellows for RF accelerators;

[0054] Fig. 21B is the prior art of superconducting RF accelerator sections including multiple bobbins, bellows and RF cavities requiring specific material properties;

[0055] Fig. 21C is the prior art, showing the RF power loss and heat dissipation due to the poor conductivity of electroplated copper;

[0056] Fig.22A is the prior art, showing surface defects, corrosion, trapped materials, inclusions, and surface roughness in conventional electroplated copper that lead to poor accelerator performance;

[0057] Fig. 22B It is the prior art that shows the inclusions in electroplated copper by size and material impurities;

[0058] Fig.23A is used +Positive Kick TM Photographs of representative multilayer metal-insulator-metal stacks deposited on substrates with barrier interfaces, demonstrating surface smoothness and the ability to control layer properties;

[0059] Fig. 23B It is used +Positive Kick TM Scanning electron micrograph of a diamond-like carbon layer deposited by the technique;

[0060] Fig.23C is a scanning electron micrograph of a diamond-like carbon layer deposited using conventional DC magnetron sputtering, highlighting its porosity and voids;

[0061] Fig.24A Depicted are snapshots of the spatial distribution of plasma potential for a representative long-kick case, where the vacuum chamber dominates over the surface area of ​​the substrate and smaller sputtering target, and the distance between the target and substrate is many mean free paths—very small potential drops reach the substrate to achieve local conformality;

[0062] Fig. 24B Snapshots of the spatial distribution of plasma potential are depicted for a representative long-kick case, where the surface area of ​​the substrate is much larger than that of the sputtering target, and the vacuum chamber components are negligible, and the distance between the target and substrate is many mean free paths—a small potential drop reaches the substrate to achieve local conformality;

[0063] Fig.24CSnapshots of the spatial distribution of plasma potential are depicted for a representative long-kick case, where the target and substrate regions are of the same order of magnitude, the vacuum chamber components are negligible, and the distance between the target and substrate is small—almost all of the potential drop occurs on the substrate to achieve good conformality of plasma bombardment;

[0064] Fig.25A Depicted Fig.24A - a graphical representation of the potential distribution shown in C and its corresponding ion energy distribution function; and

[0065] Fig.25B A diagram depicting the situation where an additional active bias is applied to a substrate to obtain additional ion bombardment energy;

[0066] Fig.26 Illustration depicting the precision fixture used to align and space the RFQ LINAC blades;

[0067] Fig.27A A graphical representation depicting surface current path lengths, interface losses, and multifactorial stresses for adjacent RF surfaces and structures for conventionally processed materials;

[0068] Fig.27B Depicted with +Positive Kick TM and Super Kick TM Graphical representation of surface current path lengths, interface losses, and multi-factor stresses on adjacent RF surfaces and structures treated by the technology;

[0069] Fig.27C depicts a graphical representation of locations along the axial direction of a cavity having regions of poor electrical contact due to macroscopic effects;

[0070] Fig.28 Illustration depicting the challenges of blade alignment and clearance;

[0071] Fig.29 is a graphical representation of a low-Q cavity that requires more input RF power to meet the cavity energy storage threshold for particle acceleration and risk of electric field variation at the blade tip;

[0072] Fig.30 It is a high-Q cavity processed with a precision alignment fixture and Graphic illustration of technology-treated coatings used to reduce RF power requirements and reduce blade tip variations to support higher axial acceleration gradients, resulting in overall compactness and power savings;

[0073] Fig.31A is a graphical depiction of the three main modes of operation of the super-kick technology achieved via modulation of the positive kick, including photographs showing representative plasma changes for the different modes;

[0074] Fig.31B depicts a diagram of the three main super-kick modes with representative values ​​of voltage amplitude, pulse width, and repetition frequency for RF-like plasma generation, high-energy ion etching suitable for insulating substrates, and high-energy metal ion implantation with stress control and densification;

[0075] Fig.32 is a prior art diagram depicting existing sputtering technology;

[0076] Fig.33A is a prior art illustration depicting an example of the variability of the turn-on dithering process under some conditions;

[0077] Fig.33B is an illustration of the prior art showing application of a shock pulse at the beginning of a main negative voltage waveform to accelerate plasma breakdown, thereby increasing the chance of arc formation;

[0078] Fig.33C An illustrative application of a super kick waveform is provided to provide pre-ionization immediately prior to application of a main negative pulse;

[0079] Fig.34A is an illustrative example of RF-like voltage modulation on the envelope of a super-kick pulse to generate additional plasma for interaction with a substrate having an average voltage greater than zero;

[0080] Fig.34B is an illustrative example of RF-like voltage modulation on the envelope of a super-kick pulse to generate additional plasma for interaction with a substrate having an average voltage less than zero;

[0081] Fig.35A is an illustrative example of a super kick waveform that facilitates deep ion etching of a substrate using RF-like voltage modulation to provide charge removal via electron bombardment in a negative cycle, thereby refreshing the substrate surface for the next ion bombardment cycle;

[0082] Fig.35B is a diagram depicting the ion energy distribution function at the substrate by modifying the effective frequency of the super-kick pulse envelope;

[0083] Fig.36 is a non-RF-like application of super-kick, exemplarily depicting the ion energy distribution for controlling metal ions of a target originating from a short kick phase and gas ions in a diffuse plasma originating from a long kick phase;

[0084] Fig.37A is a diagram depicting RF-like applications of super-kick for plasma and free radical generation;

[0085] Fig.37BAdditional illustrative details are provided on the application of RF-like super-kick pulse envelopes after termination of the main negative HiPIMS pulse, including enhanced plasma formation, radical and ion generation near the substrate, and low-energy ion bombardment;

[0086] Fig.38A is a diagram depicting RF-like applications of Super Kick for deep ion etching of insulating substrates;

[0087] Fig.38B Additional illustrative details are provided regarding the application of an RF-like super-kick pulse envelope using very high energy ion bombardment on the substrate after termination of the main negative HiPIMS pulse to etch insulating substrates using AC-like electron charge removal;

[0088] Fig.39A is a diagram depicting non-RF applications of Super Kick for high energy metal ion implantation and low energy carrier gas ion shot peening to manage film stress;

[0089] Fig.39B Additional illustrative details are provided regarding the application of a non-RF, multi-step positive kick pulse after termination of the main negative HiPIMS pulse to accelerate metal ions from a magnetic trap while limiting the energy of carrier gas ions that reach the substrate later in the super-kick pulse envelope;

[0090] Fig.40A , Fig.40B and Fig.40C is a high-level depiction of a sputtering system configured to support the generation of configurable pulse power waveforms, including super-kick and plasma effects near the substrate surface, including ion / radical formation and sheath voltage in different super-kick modes of operation;

[0091] Fig.41A is an illustration of a circuit topology for implementing user-configurable super-kick pulse generation with four discrete voltage rails (2 positive and 2 negative) and corresponding energy storage capacitors;

[0092] Fig.41B is an illustration of a circuit topology for implementing user-configurable super-kick pulse generation with three discrete voltage rails (1 positive, 1 negative, and 1 floating) and corresponding energy storage capacitors; and

[0093] Fig.41C is a diagram showing parallel combinations of series transistor switches to achieve the desired current, power, voltage, and repetition rate. DETAILED DESCRIPTION

[0094] The following detailed description of the drawings should not be taken in a limiting sense but is merely for the purpose of describing the principles of the described embodiments.

[0095] A structural assembly and system are described which, in operation, inject RF power directly into an accelerator, such as a radio frequency quadrupole (RFQ) LINAC, while placing the RF power amplifier itself, as well as the RF input circuitry and bias circuitry, outside the vacuum environment occupied by the LINAC cavity. A key aspect of the present disclosure is that it allows the LINAC cavity itself to be used as the output stage of the amplifier, thereby eliminating any need for transmission lines between the final amplification stage and the LINAC cavity. The described structural assembly arrangement exhibits a number of advantageous features. The arrangement mitigates the deleterious effects of multiple factors associated with placing components associated with the RF power amplifier in a vacuum environment. In addition, the arrangement enables inspection / replacement of the RF power amplifier without breaching the vacuum seal of the RF LINAC cavity.

[0096] The low capacitance hermetic HV breaker is particularly important for the function of the RF power amplifier arrangement described herein. The low capacitance characteristics of the hermetic HV breaker (described in detail below) ensure that the capacitance between the output stage of the RF power amplifier and the LINAC cavity is sufficiently low. As an illustrative example, the hermetic HV breaker is a piece of alumina ceramic (or other suitable dielectric material) bonded to copper (or other suitable conductive material) at both ends, for example by brazing or other suitable metal material bonding techniques.

[0097] Another aspect of the illustrative example is that the output stage of the RF power amplifier and the antenna are both placed at the same DC potential as the LINAC system. Furthermore, the illustrative example provides a mechanism to directly and easily cool the amplifier and antenna elements via a flowing liquid (e.g., water) cooling loop. An illustrative example of this aspect of the disclosure is to have the cooling loop pass through the antenna itself, with one end of the antenna mounted to the anode electrode and the other end grounded.

[0098] As an illustrative example, a system is described herein for injecting RF power directly into an RF LINAC, such as a radio frequency quadrupole (RFQ) accelerator, while placing the RF power amplifier, RF input circuitry, and bias circuitry outside the vacuum environment occupied by the LINAC cavity. Figure 1 An illustrative example of such a system is schematically depicted in .

[0099] Go to Figure 1, the main components of the exemplary depicted system include: a vacuum chamber 1 containing a cavity 2 (e.g., one or more LINAC cavities), one or more of the power amplifier components 3 (including RF power amplifier 6, hermetic circuit breaker 5 and antenna 4) directly coupled to the cavity 2 structure, and an electronic circuit interface including a set of inputs 7. The set of inputs 7 of the electronic circuit interface is configured to provide power, bias voltage / current and sufficiently high power RF energy to one or more of the power amplifier components 3. The received RF energy is amplified by one or more of the power amplifier components 3 for transmission into the cavity 2 structure.

[0100] As a further explanation / definition, the "direct coupling" used above to describe the structural relationship between the power amplifier assembly 3 and the cavity 2 is defined as an electrical energy coupling relationship such that the power transmission line between the output interface of the power amplifier assembly 3 and the cavity 2 structure is negligible. In the illustrative example, this direct coupling is achieved by the power amplifier assembly 3 having a sealed circuit breaker 5 barrier between the antenna 4 (which is coupled to the cavity 2 and maintained in a vacuum) and the RF power amplifier 6 (operating at atmospheric pressure).

[0101] As an illustrative example, Figure 2C A power amplifier assembly comprising two subassemblies is depicted. Each of the two subassemblies is further specifically illustrated in Figure 2A and Figure 2B Depicted in. Figure 2A A subassembly comprising a hermetic circuit breaker 5 is depicted. Thereafter, Figure 2B An example of an RF power amplifier 6 subassembly is illustratively depicted by way of example in the form of a compact planar triode subassembly 17 .

[0102] Go to Figure 2A , a subassembly including the enclosed circuit breaker 5 will now be described by way of a detailed example. As an illustrative example, the enclosed circuit breaker 5 is substantially cylindrical. The enclosed circuit breaker 5 includes a dielectric body 23, which is substantially cylindrical and made of, for example, a ceramic material. The enclosed circuit breaker 5 also includes a first conductive material 16a and a second conductive material 16b located at opposite ends. In the illustrative example, the first conductive material 16a and the second conductive material 16b are substantially annular and occupy the ends of the substantially cylindrical dielectric body 23 of the enclosed circuit breaker 5. Figure 2A The subassembly exemplarily depicted in FIG. 1 also includes a socket interface 9 to which the output of the RF power amplifier 6 is connected. Figure 2B , depicts a suitable structure for connecting the output of the RF power amplifier 6 to the enclosed circuit breaker 5, namely a compact planar triode (CPT) 17. Figure 2A and Figure 2B, the CPT 17 is attached at the anode electrode 18 (also called the plate electrode) to the socket interface 9 of the subassembly containing the enclosed circuit breaker 5 structure.

[0103] Continue to refer Figure 2A , the subassembly including the enclosed circuit breaker 5 also includes a fixed potential electrode 8 connected to the antenna 4. For example, the fixed potential electrode 8 is also roughly cylindrical. Therefore, in the illustrative example, a roughly cylindrical space 24 is formed between the fixed potential electrode 8 and the dielectric 23 of the enclosed circuit breaker 5. The antenna 4, which occupies an area in the range of approximately 0.1 square inches to 5 square inches, is also connected to the electrode of the socket interface 9. Since the operation of the exemplary LINAC system involves high currents, the antenna 4, the socket interface 5 and the fixed potential electrode 8 are all made of a highly conductive material (such as copper), or at least coated with a sufficiently thick layer of a highly conductive material. The term "sufficiently thick" is defined here as being equal to or greater than one skin depth at the expected operating frequency of the LINAC system. In combination with the cavity 2, the above-mentioned conductive structure determines / establishes the effective electrical impedance (Z1) observed from the output interface of the RF power amplifier 6.

[0104] Continue to refer Figure 2A , the enclosed circuit breaker 5 is physically connected to the socket interface 9 (set as two physical joints 9a and 9b in the illustrative example) and the fixed potential electrode 8 (set as two physical joints 8a and 8b in the illustrative example) at the first conductive material 16a and the second conductive material 16b. The electrically insulating ceramic material of the dielectric 23 provides a high voltage breakpoint between the RF output of the RF power amplifier 6 received via the socket interface 9 and the fixed potential electrode 8. The enclosed circuit breaker 5 also exhibits the characteristic of sufficiently low inter-electrode capacitance, which electronically manifests itself as a capacitive load C1 in parallel with the load Z1 provided by the combination of the antenna 4 and the cavity 2. The above circuit characteristics of the enclosed circuit breaker 5 are summarized in Figure 4 In the effective circuit model of the system schematically depicted in .

[0105] By way of further explanation / definition, "sufficiently low" inter-electrode capacitance is defined as such that the inverse of the inter-electrode capacitance is greater than or equal to the angular frequency of the RF input times the magnitude of the antenna impedance. Figure 2AIn the depicted illustrative example, the high voltage breaking characteristics of the hermetic circuit breaker 5 are achieved by joining the first conductive material 16a and the second conductive material 16b to the dielectric 23 through two ceramic-metal seals (e.g., alumina-copper joints achieved via brazing or diffusion bonding), each of which is located at the end of the generally cylindrical dielectric. The metal side of each joint formed by the first conductive material 16a and the second conductive material 16b, respectively, has a mechanical stress relief structural property / feature 16 to account for the difference in thermal expansion coefficients between the two different materials (metal and ceramic) of the hermetic circuit breaker 5 and thereby promote reliable bonding. Various insulator breaking and hermetic sealing configurations are considered for coupling the RF amplifier output with the cavity structure and vacuum chamber signals. In a specific illustrative example, directly joining the high conductivity copper (16a and 16b) to the ceramic material (23) produces excellent RF power transmission capabilities compared to the conventional Kovar to ceramic brazing process, thereby avoiding the potential difficult / challenging further step of subsequently coating the exposed metal surface in a highly conductive material (such as copper). Although in Figure 2A 8. Although shown as separate physical features in FIG. 1, it should be noted that in other illustrative examples, the first conductive material 16a can be an integral part of the structure of the fixed potential electrode 8. Similarly, the second conductive material 16b can be an integral part of the structure of the socket interface 9.

[0106] When the antenna 4 is configured as a loop antenna structure, such as Figure 2A As is the case in the example exemplarily depicted in , antenna 4 may be constructed from a hollow tube through which a coolant may be controllably passed to achieve desired temperature control of system components. Figure 2A 1 and 2. A coolant input / output structure 13 is depicted in FIG. The coolant input / output structure 13 is connected to the antenna 4 (hollow tube structure) via a set of two channels 14 passing through the fixed potential electrode 8, into which the coolant input / output structure 13 and the antenna 4 tube are inserted and then welded, brazed, epoxyed or otherwise sealed. In addition, a cavity 15 for coolant flow within the socket interface 9 allows for more efficient cooling of the RF power amplifier 6.

[0107] according to Figure 2A In the illustrative example depicted in FIG, a ConFlat (CF) flange 10 can be used in conjunction with a bellows 11 to ensure that the structural interface of an RF power amplifier assembly can mate with a vacuum chamber while maintaining tolerance for manufacturing errors in the power amplifier assembly 3, cavity 2, or vacuum chamber 1, which requires the power amplifier assembly 3 to maintain a certain variability / adjustability in its positioning.

[0108] An alternative to the above approach is to make the vacuum seal permanent, rather than removable. This can be achieved, for example, by replacing the CF flange 10 with a welded, brazed or epoxy joint. The fixed potential electrode 8 and the bellows 11 are connected via a cylindrical housing 12, the function of which is simply to provide a structurally reliable vacuum barrier between where the power amplifier assembly 3 fits into the cavity 2 and where it fits into the vacuum chamber 1.

[0109] Regardless of any specific illustrative example, with the RF power amplifier 6 located on the air side of the vacuum chamber 1, detrimental effects such as multiplicity factors and surface flashover can be minimized or even eliminated for power conditions of a LINAC or other RF cavity structure. This is a significant improvement over the current state of the art. Power dissipation and cooling can further be managed outside of the vacuum environment.

[0110] Furthermore, by way of illustrative example, the RF power amplifier 6 of the illustrative RF power amplifier assembly (which may include several instances of the RF power amplifier 6) may be quickly replaced for programmed maintenance or replaced at the end of its life without evacuating the vacuum chamber 1. Figure 2C In the illustrative example depicted, this is accomplished by removing the electronic interface to which the input 7 is applied, and then removing the RF amplification element 6, which is replaced before reinserting the physical interface for the input 7. Figure 2C In the depicted example, the socket interface 9 comprises a threaded socket into which the threaded anode electrode 18 of the CPT 17 is screwed. Figure 2B In the illustrative example provided in , the grid electrode 19 , cathode electrode 20 , and filament electrode 21 of the CPT 17 are connected to a connector interface providing input 7 .

[0111] Go to Figure 3 An illustrative example of the disclosed system / apparatus includes integrating 4 to 12 power amplifiers onto a radio frequency quadrupole accelerator to produce a particle beam with an energy of approximately 2 to 5 MeV. Figure 3 An illustrative cross section is shown in Figure 2, showing four power amplifier assemblies 3a, 3b, 3c and 3d arranged symmetrically around cavity 2. Such a system can be used to generate neutrons, gamma rays and high energy ions for a variety of scientific, medical or industrial purposes. The power amplifiers are integrated directly onto the RF quadrupole accelerator, eliminating the entire equipment rack, RF power combining equipment, waveguides and power conditioning hardware. Since the RFQ cavity is essentially a power combining cavity, the exemplary depicted / described system / apparatus uses the power combining cavity for dual purposes: (1) combining multiple amplifiers for use on a single LINAC system, and simultaneously (2) establishing electromagnetic fields to accelerate particles to high energies.

[0112] It can thus be seen that a new and useful system for coupling / injecting RF power into an RF LINAC has been described. In view of the fact that the principles of the present disclosure can be applied to many possible embodiments, it should be recognized that the examples described herein with respect to the accompanying drawings are merely illustrative and should not be considered to limit the scope of the present disclosure. For example, those skilled in the art will recognize that the elements of the illustrative examples depicted in the functional blocks and depicted structures can be implemented in a variety of electronic circuits and physical structures understood by those skilled in the art. Therefore, the illustrative examples may be modified in arrangement and detail without departing from the spirit of the invention. Therefore, the invention described herein covers all such embodiments that may fall within the scope of the following claims and their equivalents.

[0113] Conventional structures and systems for manufacturing RF LINAC systems involve taking large blocks of special grades of material or alloys, such as niobium metal, beryllium metal, ultra-high purity oxygen-free copper, and precision machining them to obtain precise dimensional tolerances for narrowband resonant cavities used for RF acceleration. For many accelerator components, only a few percent of the bulk material is used, resulting in a significant loss of material, time and labor. This comes at a great expense to maintain material properties; and to minimize the number of lossy interfaces, tolerance / stack-up errors, seal breakages and mismatches. Typically, substrate materials are used for their excellent structural properties, but at the expense of electrical or thermal properties. Compromise options include using stainless steel instead of copper, or conversely choosing niobium instead of copper. Because at high frequencies (e.g., MHz), electrical properties dominate the skin depth of electromagnetic propagation in the material, a composite structure with a surface layer that exhibits excellent electrical and vacuum properties is used.

[0114] For composite structures, different materials can be selected for different components to obtain thermal properties, structural support, expansion and contraction, vibration resistance, etc. With the ability to form composite structures, novel methods of manufacturing, alignment, fixation, and segmentation help reduce costs and increase design flexibility for reduced weight, size, and power, and ease of integration. In particular, ideal surface material properties (e.g., low electron emission), material purity (e.g., low inclusions, low field concentration), cavity smoothness (e.g., low field emission, high gradient), near-surface morphology (e.g., limited whisker growth, spark initiation), and vacuum tolerance (e.g., low vapor pressure, surface mobility) can be designed to improve the characteristics of RF LINACs.

[0115] The fabrication operations and techniques described herein also allow for the use of stronger, more thermally conductive and more easily formed / machined / processed materials, replacing bulk solid niobium materials with thin layers for superconducting cavities. Due to the diversity of materials that can be deposited on a variety of substrates, this technology provides more options and choices for accelerator cavities and components.

[0116] RFQ LINACs are complex to manufacture due to the precision blade structure that requires the blade tips to be aligned, spaced, and assembled into four equally sized quadrants to achieve RF load balance. Conventional RFQ LINACs are manufactured using a primary-secondary blade configuration that is integrated together with multiple axial components to achieve the desired acceleration length. Typical RFQLINACs operating around 200-425 MHz are tens of meters in length and are used for hydrogen ion acceleration to several MeV. These machines are large, costly, and are typically found in national laboratories, medical centers, and research universities. Direct sputter coating of the interior can seal interfaces between components such as blades, spacers, tuning rods, bellows, etc. However, the sputter coating methods and structures described in this article are broadly applicable to a variety of applications beyond coating the internal surfaces of RFQLINACs.

[0117] The thin film deposition, etching, and surface modification methods herein enable composite architectures, low-complexity integration, and improvements in surface material properties to enable higher-gradient operations. Figure 5A is a photograph of the exterior of an RF LINAC cavity for a radio frequency quadrupole accelerator. In the example shown, the RF cavity serves as an external vacuum chamber with multiple ports designed to receive Figure 1 RF power amplifier components depicted in FIG.

[0118] Figure 5B is a photograph of the interior quadrant of an example RF cavity formed by the rigid attachment of four blade structures prior to surface modification and formation of a continuous RF seal. The four blade structures 5101 are inserted into the RF cavity and bonded in place with material 5102. A precision fixing fixture (not shown) is attached to the four blade structures 5101 and blade tip alignment, positioning, gap spacing and tolerances are performed externally prior to insertion into the RF cavity substrate 5100. Once the properly gapped and aligned blade structures 5101 are inserted, the fixed blades are rigidly attached to the RF cavity substrate 5100. The attachment structures vary and include, for example, welds, machine screws, turnbuckles, epoxy, low temperature brazing, etc. In the Figure 5B In the example shown, conventional solder is baked at a low temperature in an inert oven. As described in detail in the following sections, Thin film deposition, etching and surface modification techniques are used to coat the interface with a highly conductive copper layer for continuous cavity surfaces to achieve high Q values. Figure 5C In contrast, Figure 5CA prior art primary-secondary blade structure for RFQ with alignment gaskets and RF seals at each interface is shown. Because the RFQ LINAC is thermally cycled and materials age, the interface between the primary and secondary blades requires additional compressive forces and restorative contact to maintain low resistance for high surface conductivity to the RF current. Therefore, under ideal operating conditions, for example, a cavity Q of 4500 versus 10000 achievable with smooth solid surface copper, the achievable cavity Q may be 10-80% of the theoretical maximum. During sputtering deposition operations, a variety of mixed materials, including ceramics, semiconductors, and metals, can be deposited on the RF cavity walls, with most of the RF current and energy being used to deposit the cavity Q at known locations. +Positive Kick TM As an illustrative example, the sputtering deposition technique provides good coverage and sealing surfaces for room temperature Cu and superconducting cavities such as Nb or Nb / NbN, Nb3Sn or MgB2.

[0119] Fig. 6A and Figure 6B The applications of the surface coating systems and operating methods disclosed herein are illustratively depicted. That is, thin film etching and deposition on particle accelerator electrodes and electromagnetic cavity structures are illustratively depicted. Fig. 6A The cross-sectional area of ​​a four-blade radio frequency quadrupole (RFQ) accelerator cavity is depicted. The inner four quadrants of the RFQ accelerator cavity are subject to intense electromagnetic fields and surface RF currents during operation. In order to achieve high accelerating gradients during operation, very high electric fields are used. Therefore, the quality of the surface coatings within the cavity, including microstructure and conductivity, is critical to achieving high performance. The surface coating structures and methods disclosed herein facilitate surface preparation, cleaning, etching, adhesion, and deposition of high-quality materials, thereby improving the quality and performance of deposited coatings during RFQ accelerator operation. Fig. 6A In the illustrative example of , a sputtering target (e.g., sputtering target 6001) is inserted into a vacuum environment 6011 of an accelerator chamber substrate 6006. A magnetic assembly (e.g., assembly 6038) within the sputtering target 6001 generates a magnetic field 6012 that generates and maintains a dense plasma region 6013 to generate ions and neutral particles 6004 that are well deposited on the substrate 6006. For example, this is achieved by introducing a gas in the range of 0.01-100 mTorr into the vacuum environment 6011, typically an inert gas such as Ar or a reactive gas such as N2, a voltage in the range of 200-2000 V, and a magnetic field of 100-1000 s Gauss. During operation of the sputtering deposition operation, energetic ions and neutral particles 6004 are generated and directed toward the substrate 6006.

[0120] Figure 6B yes Fig. 6AAn illustrative example of a photograph during actual operation for depositing highly conductive copper directly onto the inner surface of the RFQ accelerator chamber, where the blade structure is fixed and directly soldered to the RFQ accelerator chamber surface. The sputter-deposited copper is directly coated on the inner surface including the solder material to form a continuous copper layer that exhibits excellent sealing and surface properties. Figure 6B , four (4) sputtering targets 6001 with dense plasma regions 6013 are contained within a vacuum environment 6011, visible during insertion of an RFQ chamber substrate 6006. The dense plasma regions 6013 are clearly visible within the vacuum environment 6011. Highly conductive copper with a dense nanograin structure can be deposited with an ultra-smooth surface roughness to withstand high electric field gradients. The nanograin texture resists slip plane whisker growth, which promotes surface electric field concentration and sparking under high electric field gradients. The illustrative examples described herein avoid this problem.

[0121] Furthermore, the presently disclosed material deposition operations, described in the context of providing excellent sealed copper conductive surfaces for RFQ accelerator cavities, can also be used for superconducting thin films and layers, such as Nb, Nb / NbN, etc. and PositiveKick TM and aspects of the present disclosure, controlling film morphology and crystallinity to achieve preferred grain orientation, grain size, lattice plane matching, surface roughness, and other parameters to obtain excellent residual resistivity ratios, current density, and magnetic properties.

[0122] Figure 6C A composite RF LINAC cavity composed of one or more bulk substrate materials with one or more material coatings is depicted. The materials that make up the blades, such as blade 6101, are fixed to the walls of the RFQ accelerator cavity relative to each other according to the specific design of the RFQ accelerator and are attached to the RFQ accelerator cavity substrate 6100 using a bonding material 6102. The material of the cavity substrate 6100 is selected based on its desired material properties, such as: structural, thermal, cost and ease of manufacturing. The materials that make up the blades, such as blade 6101, are selected based on their properties, such as thermal conductivity, coefficient of thermal expansion, machinability, compatibility with copper coatings, etc. The actual bonding of the blade 6101 to the surface of the cavity substrate 6100 is performed using the bonding material 6102, for example using a combination of mechanical and chemical attachment structures. A sputtering target, including a sputtering target 6001 with a corresponding magnetic assembly 6038, is inserted into a vacuum environment 6011 for surface modification, etching and deposition. The sputtering target 6001 material can be any of a variety of materials selected to obtain different compositions with different properties for specific RFQ accelerator applications.

[0123] Fig.6DAn enlarged view of the previous figure is depicted to provide a more detailed description of an in-situ sputtering electrode that emits ions and neutral particles (neutrals) to coat one or more surfaces of an RFQ accelerator cavity substrate 6100. A stream of energetic ions and neutron particles 6004 is directed to surfaces within the RF cavity and accelerator components to produce thin or thick film surface coatings 6103 having engineered properties.

[0124] Fig. 6E A further magnified close-up view of a composite RF LINAC cavity is depicted, where the blades 6101 are rigidly secured to the vacuum enclosure via a mechanical / thermal interface, and a thin film continuous coating serves as an electrical interface. The thin / thick film surface coating 6103 provides a continuous, smooth electrical path in the transition from the RFQ accelerator cavity substrate 6100 to the bonding material 6102 to the material on the outer surface of the blades 6101. At MHz RF frequencies, the electrical skin depth of electromagnetic propagation is only a few microns. Therefore, from the vantage point of the RF cavity, the RF energy cannot reach ("see") the underlying materials (beyond the skin depth), and the performance of the multi-layer composite structure can therefore be optimized, where the electric field characteristics are emphasized within the skin depth range, and the mechanical, structural, cost, manufacturing characteristics / considerations dominate at distances beyond the skin thickness layer.

[0125] Conventional wet chemical and electroplating techniques are limited in terms of substrate material selection, substrate shape, contamination, surface material finish, and adhesion strength. The innovative manufacturing features of the present disclosure described herein are based on the use of conformal physical vapor deposition of various materials in combination with surface etching, preparation, and modification techniques.

[0126] Fig. 7A An axially inside cross-sectional view of an end cap cylindrical magnetron emitting ions and neutral particles is illustratively depicted, highlighting the internal coolant flow, magnetic assembly, and external plasma generation. A sputtering target electrode 7001 is mounted on an end cap assembly 7106, wherein internal cooling channels 7105 flow coolant through the magnetic assembly 7038 and the sputtering target material 7001. There may be a target support between the material 7001 and the cooling water and magnetic assembly 7038. For example, the magnetic assembly is mounted to a structure that facilitates the rotation 7039 of the structure that provides a dense plasma region 7013 around the sputtering target electrode 7001.

[0127] Figure 7B exist Fig. 7AThe sputtering electrodes are depicted in an orthogonal cross-sectional view of the structure depicted in the side cross-sectional side view of FIG. 7039, highlighting the relative rotation of the sputtering target material and the magnetic assembly. The rotation 7039 allows the magnetic field 7029 from the magnetic assembly 7038 to move relative to the target material 7001. In the illustrative example, the magnetic assembly 7038 is mounted to the target support 7008. The dense plasma region 7013 generates energetic ions and neutral particles 7003, which are directed outward from the sputtering target material 7001 toward the surface to be coated, etched and modified of the RFQ accelerator cavity substrate (not shown).

[0128] Figure 7C 7001 ) is a photograph of a 1.5 meter long sputtering electrode embodiment in which the magnetic field is arranged to produce a single serpentine dense plasma zone around the sputtering electrode. The electrons are caused by the Hall effect ExB force (also known as the "magnetron effect") generated by the voltage applied to the sputtering target electrode 7001 to run around the continuous serpentine track, resulting in the generation of an intense plasma zone 7013. Because it is a single track, the plasma density can be better load balanced on the cylindrical magnetron surface, thereby achieving better uniformity over the entire length. In this specific example, a 1.5 m long plasma region is formed over a length suitable for azimuthal rotation with good uniformity.

[0129] Fig.7D is a photograph of an end cap cylindrical magnetron 7106 operating with a single serpentine racetrack dense plasma region 7013 on a sputtering target electrode 7001. Fig.7D In the end cap cylindrical magnetron 7106 adopts +SuperKick TM The plasma mode is used to generate electromagnetic fields to perform cleaning, etching and surface modification, as evidenced by the blue-pink-purple color on the copper sputtering target electrode 7001 (when operated in situ). In this plasma mode, the end cap cylindrical magnetron 7106 generates high energy Ar+ ions and directs the ions radially outward to clean the surface of the object to be processed (e.g., the RFQ accelerator cavity).

[0130] Advantageously, during surface machining and processing operations, changes can be made in less than a second. Operating parameters to switch the operation of the component from performing a cleaning / etching operation to a deposition / implantation operation. Fig. 7E yes Fig.7D Photo of the same system shown, using +Positive Kick TM Technology is used to generate electromagnetic fields for performing implantation, mixing, adhesion, stress control, morphology control, diffusion barriers and capping layers, as evidenced by the bright green copper plasma color of the sputtering target electrode 7001 (when operated in situ).

[0131] Figure 7F is a photograph of a 6.3 mm diameter end cap cylindrical magnetron 7106 with various illustrative examples in which a magnetic field assembly 7038 is arranged to produce multiple axially translatable dense plasma zones 7013 around a sputtering target electrode 7001. This configuration is suitable for processing the inner surfaces of very small diameter structures and coating the inside of small tubes and hard to reach locations. However, the structure can also be used to process the surfaces of larger items.

[0132] Using the cylindrical magnetron configuration discussed above, as well as other configurations including inverted cylindrical, planar, and rotary, Ultrafast High Power Impulse Magnetron Sputtering (HiPIMS) technology can be used to generate dense metal plasma and ultrafast voltage reversal for Positive Kick TM and Super Kick TM Technology to accelerate ions and plasmas to substrates for modification. Fig. 8A Describes the use +Positive Kick TM Example of conformal coating of a substrate. During the HiPIMS pulse, the current can be 10-1000 times higher than in conventional DC sputtering. Combined with ultrafast Pulse technology can achieve a peak power density of <<100usec, thus generating a very high plasma density. TM The voltage reversal and forward bias pushes the ions and plasma away from the dense magnetic field region on the magnetron to increase the local plasma density near the substrate during the pulse. This high density bulk plasma 831 will have a short Debye length, enabling it to penetrate the 3D structure 823 of the substrate 806. Applying a positive kick will initially accelerate the ions from the magnetic confinement region with a directional energy 868 that follows Grad B, and eventually cause the bulk plasma potential to rise so that a conformal sheath 881 appears around the substrate 806 and additional ions 869 are accelerated to the substrate. If the feature is larger than several Debye lengths, conformal deposition will occur. Another result of the positive kick is an increase in ion capture efficiency 864, which is important from an economic point of view.

[0133] Figure 8B is a photograph that depicts the use of Positive Kick TM and SuperKick TMThe end cap cylindrical magnetron technology is used to perform surface coatings achieved with conformal thin film copper coatings to replace conventional electroplating and wet electrochemistry of stainless steel cryogenic accelerator bellows. In the foreground, the substrate 8006 to be coated is made of hydroformed stainless steel suitable for cryogenic applications. The received material is inserted into the cylindrical magnetron system and Apply Positive Kick TM , for adhesion and surface adsorption atom mobility, and for applying Super Kick TM , for etching / cleaning. Continuous thin / thick film 8013 is conformal deep within the bellows channels. Adhesion and film quality are sufficient to survive a 400°C air bake and immediate immersion in LN2 without flaking, delamination, or material failure. Material is cycled through over 1000 full range expansion / compression strokes without film failure.

[0134] Conformal coatings are achieved on accelerator surfaces, including the RF cavity, RF seals, bellows and actual blade tips, IH structures, dielectric load structures, tuning elements and electrodes. Low secondary electron emission, smooth and high field emission limit materials can be deposited and adhere well at high stress locations, while highly conductive bulk materials can be coated in areas where low resistance is required. In the case of a four-blade RFQ accelerator cavity surface treatment, the blade tips are coated with a coating for the high field region and the cavity region is coated with different types of membrane structures. For example, ultra-smooth, nanocrystalline or amorphous high gradient materials on the blade tips and preferentially oriented high conductivity copper in the cavity region.

[0135] Fig.9A A graphic representation of sputtering target erosion and wear of a narrow V-groove is depicted. Under HiPIMS conditions, higher magnetic field positions 9044 generate higher plasma density 9013, resulting in more local current and sputtering from positions 9045 on the cosine 9047 relative to the surface normal. The deeper the V-shaped channel 9043, the smaller the solid angle 9046 for material escape and the higher the amount of material recovery, reducing the overall deposition efficiency of the system. For multiple racetracks, the racetrack grooves on some racetracks may be deeper than on others. This speeds up maintenance cycles. Fig. 9B An illustration of sputtering target erosion is depicted where there is relative motion between the dense plasma region and the sputtering target material for uniform erosion. Higher uniformity and fewer grooves 9047 can be achieved through rotation or axial adjustment of the magnetic field relative to the target to obtain greater solid angle emission 9049 and target utilization 9048.

[0136] Fig.10 The conventional DC magnetron sputtering (low current, low ionization), pulsed DC (low current, low ionization, but better for reactive gases), conventional HiPIMS (high current, high ionization, but low deposition rate) and +Positive Kick TM (High Current, High Ionization Rate, and High Deposition Rate) comparison. Typically, HiPIMS plasma current density is ~0.3A / cm2. Using ultrafast pulses followed by a positive kick pulse can exceed 3A / cm2 with good film properties and is used as a factor in the design of inverted magnetron structures for more intense ionization, high peak power conformal plasma etching and deposition.

[0137] Fig.11 Schematic depicting the first of three phases during IMPULSE pulse operation - the ultrafast HiPIMS phase. Fig.11 Adapted from US application publication US20180358213A1, and exemplarily depicts ultrafast high-power pulsed magnetron sputtering and the potential distribution between the sputtering target and the substrate.

[0138] Fig.12 Depicted Illustration of the second of the three phases during the maneuver - the short kick phase. Fig.12 Adapted from US20180358213A1 and illustratively depicts ultrafast switching and reversal of positive to positive voltage on the target electrode and the evolution of the potential distribution over the magnetically confined region near the target electrode—short kicks accelerate ions from the dense HiPIMS plasma region away from the target electrode, typically perpendicular to the magnetic field lines.

[0139] Fig.13 Depicted Illustration of the 3rd of 3 phases during the operation - the long kick phase. Fig.13 Adapted from US20180358213A1, and illustratively depicts the evolution of the positive potential into a long kick phase, where the plasma potential of the bulk increases and a conformal sheath forms over the substrate and other surfaces to which the bulk plasma is commutated.

[0140] One aspect of the disclosure provided herein is the ability to control the flux and energy of ions deposited / impinged onto a substrate during operation of the apparatus described herein for the preparation and deposition of thin films with engineered properties. By combining ultrafast high current pulses with rapid positive voltage reversals of a cylindrical magnetron configuration, a high level of customization is provided, resulting in superior and novel films, including advanced nano-layered composites and functionally gradient materials with specific properties, including high electrical gradient spacing, high voltage tolerance, high electrical conductivity, ultra-smooth surfaces, oxidation resistance, thermal fracture toughness, crack arrest characteristics, diffusion barriers and wear resistance, corrosion resistance, ductility and stiffness, lubricity, etc. In particular, deposition of superconductor-insulator-superconductor layers with low bulk temperatures is highly desired by superconducting wires, tapes, RF cavities, and accelerator engineers.

[0141] Fig.14 Illustratively depicts core advantages in combined cleaning 14072, etching 14073, ion implantation 14074, adhesion control 14075, stress management 14076, bulk material deposition 14077, diffusion barrier or insulating layer 14078, and reactive / capping layer 14079 deposition. Ultrafast with positive voltage reversal through precise ion energy control Surface contaminants can be removed, near-surface damage can be etched, hybrid interfaces can be developed for good adhesion layers to support stress control layers, and bulk films can be grown through suitable interfaces and capping layers. Fig.14 Depicted for use without breaking vacuum, interruption or segmentation +Positive Kick TM +Super Kick TM Illustration of the continuous process 14071.

[0142] Fig.15 is an oscilloscope waveform of a copper sputtering plasma reaching a 2kA peak current in 20 microseconds during the ultrafast HiPIMS phase, followed by a +200V positive pulse showing the short kick and long kick phases. Voltage waveform 15055 and current waveform 15058 for a -750V, 2kA peak current HiPIMS pulse to achieve a plasma current density of 5A / cm2 on a cylindrical magnetron with a copper sputtering target with a +200V, 125A peak current positive kick pulse highlighting the short kick 15056 and long kick 15057. Technology drives plasma generation with high dI / dt to achieve rapid ionization for subsequent voltage reversal and positive kick TM , to accelerate ions and plasma into the substrate for excellent cleaning, etching, preferred orientation deposition, and deposition with stress and morphology control. This technology also allows synchronization with a pulsed DC bias power supply for time window acceleration into the substrate for additional control, as taught in US20180358213A1.

[0143] The main negative pulse on the voltage waveform 15055 is typically in the range of -400V to -1200V, depending on local factors such as pre-ionization, target material, magnetic field, pressure, geometric curvature, sputtering gas, surface chemistry, adsorbed gas, etc. Using ultra-fast switching topology, the typical high current pulse width is less than 100usec, with a typical range of 20-50usec. Positive Kick on the voltage waveform 15055 TMThe amplitude is typically in the range of +0-600V. For users who do not want the short kick ion group to accelerate away from the sputtering target, the start delay of the positive kick will be set after this period, as shown in the current waveform of the short kick 15056, which is typically set to 20-40usec. The ionization rate and plasma density near the sputtering target are highly coupled to the effective current density. The effective current density is in the range of 0.1-10A / cm2.

[0144] Fig.16 is a photo of a conventional planar magnetron using an ultrafast short main pulse for deposition followed by a positive kick TM The quasi-RF modulation of the pulse operates to generate and maintain a secondary plasma with a positive potential relative to the substrate for etching. Each pulse cycle will be a combination of deposition and etching - in the case of a copper sputtering target, copper deposition of preferred orientations such as Cu(211) vs. Cu(111) vs. Cu(100) is achieved. The etching parameters are adjusted for preferred orientation and epitaxial growth conditions. Sputtering target 16001 is processing a negative main pulse and an RF modulated positive pulse. The dense plasma region 16013 above the racetrack is a bright white-green color emitted by the Cu I and Cu II light emission lines. The central plasma region 16080 excited by the RF modulation of the positive voltage is colored pink by the excitation of Ar I and Ar II. The central plasma region 16080 extends all the way down to the insulating substrate 16082, which exhibits a combination for deposition and etching surface 16083. The conformal plasma sheath 16081 extends down to the insulating substrate 16082. Using this combination for deposition and etching, a thin film of preferred orientation can be deposited.

[0145] Fig.17A φ(R) is an oscilloscope trace showing a -10-100 kHz RF-like modulation (such as frequency and / or amplitude) of a positive pulse to generate a plasma with a positive RF bias. Fig.17A and Fig. 17B It is the highlight of Super Kick TM Photograph of a mode for extended plasma generation away from a magnetic field and etching on a substrate, sample oscilloscope waveform 17086 ( Fig.17A ) shows the current waveform 17058 of the RF-like oscillation operated at 77kHz and the voltage waveform 17085 of the RF-like voltage applied. Fig. 17BThe photo in shows a bare target electrode 17001 with no bright visible emission from the racetrack region. The absence of any dense plasma region indicates that no sputtering is occurring on the target. The bright central plasma region 17080 follows the magnetic nozzle / tip into the target electrode and is commutated to the target electrode 17001 at an elevated positive potential. The resulting etching plasma extends down to the substrate 17084 with a visible plasma sheath 17081 in line with the sample. Super Kick TM The pattern can persist indefinitely under a range of direct etch operating conditions. TM It can also be used in conjunction with a negative DC bias on the substrate to increase flexibility in material processing.

[0146] Fig.18 Describes the Schematic diagram of the thin film deposition, etching and surface modification system with pulse modules and power supplies. Fig.18 It is a diagram showing the sputtering target electrode, return electrode, substrate, plasma in a vacuum environment, and one or more The HiPIMS pulse module (its main and kick supplies) and any Schematic block diagram of an illustrative example of an electrical component / circuitry arrangement between bias pulse module power supplies. Fig.18 The schematic diagram in the figure outlines the process for deposition and etching. General setup of the system. High voltage electrical pulses are provided directly to the sputtering target from an external pulse power module through appropriate insulation and low impedance connections. This allows a low impedance electrical connection to the sputtering target holder through a rotating magnetic assembly for efficient power transfer and coupling. The modules are designed for parallel synchronous and asynchronous operation. Therefore, multiple units can be pulsed in parallel to deliver the power, rise time and plasma density required for the sputtering target configuration.

[0147] Fig.19 An example structural area diagram with two independent axes representing effective temperature (T*) and effective sputtered particle energy (E*) is exemplarily depicted, which can be represented by and Positive Kick TM Perform addressing. Fig.19Illustration of a modified Thornton structural zone diagram via Andre Anders' generalized energy condensation, extending the control of film microstructure and morphology. Adjustment of the HiPIMS pulse amplitude, pulse width, timing, peak current density, repetition rate and pressure for a given substrate to sputtering target distance, magnetic field geometry and field distribution allows control of the main pulse particle flux (T*) approximated as a thermal spike. More intense short pulses with higher particle loading in a shorter time have a high temperature effect that equilibrates the deposited material and adjusts it towards fibrous transitional grains (zone T), columnar grains (zone 2) and recrystallized grain structures (zone 3). Adjustment of the HiPIMS pulse amplitude, pulse width, timing, peak current density, repetition rate and pressure for a given substrate to sputtering target distance, magnetic field geometry and field distribution allows control of the main pulse particle flux (T*) approximated as a thermal spike. More intense short pulses with higher particle loading in a shorter time have a high temperature effect that equilibrates the deposited material and adjusts it towards fibrous transitional grains (zone T), columnar grains (zone 2) and recrystallized grain structures (zone 3). Adjustment of the positive kick pulse amplitude, short / long kick pulses, start delay and any super-kick effects of RF-like oscillations of the available plasma generated by HiPIMS pulses will allow for tuning of the effective energy (E*) and adjustment of film microstructure and morphology. And positive kicking allows moving around Anders / Thornton SZDs to even achieve fine-grained nanocrystalline films and dense amorphous glass films with preferred orientation and low-temperature low-energy ion-assisted epitaxial growth regions. Process engineers can move around SZDs to achieve tensile / compressive stress control, columnar growth with nanocrystals with preferred orientation, etc.

[0148] Fig. 20A and Fig. 20B is used as a power source in the system described herein in the embodiments of the present disclosure 2-2 System and Photo of the 20-20 system.

[0149] Fig.21A is an example of a bellows structure having a surface treatment / formation using prior art methods, for electroplating stainless steel cryogenic bellows for RF accelerators. Fig.21A In the images provided, the varying quality of copper plating can be observed due to mask and nickel strike layer difficulties that prevented deposition of the sheet on the sidewalls of the vacuum bellows section. Prior art methods can be replaced with the beneficial results of better surface preparation / plating by using the deposition / sputtering operation of the present disclosure.

[0150] Fig. 21B Illustratively depicted is a prior art arrangement for a superconducting RF accelerator section, the arrangement comprising multiple bobbins, bellows and RF cavities requiring specific material properties.The present disclosure relates to multiple sections having a wide range of applications.

[0151] Fig. 21CThe performance characteristics of the prior art are depicted illustratively, showing the RF power losses and heat dissipation due to the poor conductivity of electroplated copper. The thickness of the film determines the magnitude of the RF losses and the ability of the structure to conduct the deposited thermal energy outward. This is important not only for the accelerator cavity, but also for bellows sections, transfer tubes and other beam structures.

[0152] Trapped RF modes are a source of heat present in accelerator structures such as bellows. For superconducting accelerator cryomodules maintained at liquid helium temperatures, any heat energy deposited here will be removed only via conduction along the bellows surface to its edges. To minimize heating, near-pure (e.g. high RRR) copper films with thicknesses >10μm are highly desirable for these applications. +Positive Kick TM The technology solves this problem by enabling stress control in the deposited film. This enables process engineers to deposit films with little to no internal stress, which is critical for thick, large-area films.

[0153] like Figure 8B As shown, the present invention allows very thick, stress controlled, fully dense, highly conductive, well adhered coatings to meet this challenge. Low temperature deposition using positive kick and IMPUSLE allows higher effective T* and E* to obtain the correct orientation without high bulk temperature that causes interdiffusion between layers. Increasing the kick voltage / duration knob makes sense. Changes T* on the Thornton zone plot without directly heating the substrate. Low actual substrate temperature prevents diffusion in nanolayered materials (e.g. SIS structures). Adjustable surface mobility that favors low defects is critical for SC films.

[0154] Fig.22A is a collection of photographs of surfaces treated according to the prior art, showing surface defects, corrosion, trapped material, inclusions and surface roughness in conventional electroplated copper that lead to poor accelerator performance. +Positive Kick TM and Super Kick TM Pattern controls net deposition, etching or both for smooth / rough fill. Re-planarization of the surface favors high gradient (i.e. spark resistant or spark resistant) accelerator films. Initial spark resistance is smooth, but overall resistance comes more from the lack of inclusions provided by depositing a controlled film in an atom-by-atom process rather than batch casting and machining. After the first arc, the local surface is no longer smooth. Therefore, film impurities / defects / inclusions determine the properties of the treated surface.

[0155] Fig. 22Bis an illustrative summary of surface properties treated in accordance with the prior art. The summary shows the size and material impurities of inclusions present in electroplated copper. According to the present disclosure, the surface treatment and formation operations and structures described herein enable controlled deposition of materials on an atom-by-atom basis, greatly limiting the size and composition of inclusions to suppress local field enhancement and multiplicity factors and sparking.

[0156] The illustrative example presented uses conformal ionization physical vapor deposition to replace wet chemical plating (e.g. copper) for stainless steel bellows and specialized vacuum parts on accelerator structures. Wet chemical plating is being phased out due to its damaging effects on the environment, handling of hazardous chemicals, high costs, and lack of experienced tradespeople in this field. In the EU, there are proposals and timelines to completely phase out all electroplating within the next few years, making investment in alternative technologies very important. Surface finish / roughness (including macroscopically visible streaks in the deposit), inclusions, particles from the copper plating itself, and particles that may be introduced during plating or subsequent surface smoothing steps (e.g. molybdenum wool polishing or sandblasting) are all known issues.

[0157] Fig.23A is used +Positive Kick TM Photograph of a representative multilayer metal-insulator-metal stack deposited on a substrate with a barrier interface, demonstrating surface smoothness and the ability to control layer properties. Fig. 23B It is used +Positive Kick TM Scanning electron micrograph of a diamond-like carbon layer deposited using the TU / D-type technique. Fig.23C This is a SEM image of a diamond-like carbon layer deposited by conventional DC magnetron sputtering, highlighting its porosity and voids. The microstructure and morphology of the thin film coating can be measured using +Positive Kick TM Control is performed as described in U.S. Application Serial No. 16 / 801,002, filed on February 25, 2020, and entitled “METHOD AND APPARTUS FOR METAL AND CERAMIC NANOLAYERING FOR ACCIDENT TOLERANT NUCLEAR FUEL, PARTICLE ACCELERATORS & AEROSPACE LEADING EDGES.” Producing nanocrystalline or preferentially oriented films near the surface can minimize surface roughness, whisker growth, and slip plane stretching growth dynamics, which are partially responsible for electric field concentration, multiplication, and spark / arc formation.

[0158] like Fig. 8AAs shown, Positive Kick TM An important aspect for applications in conformal deposition is the long kick and the ability to create a dense plasma and a local sheath potential drop around the substrate to be coated. If the target plasma area is small compared to the vacuum chamber and the vacuum chamber is located near the sputtering target, most of the positive kick TM The energy flow will go to the vacuum chamber instead of the substrate. Fig.24A Depicted are theoretical snapshots of the plasma potential spatial distribution for a representative long-kick case, where the vacuum chamber dominates over the surface area of ​​the substrate and a smaller sputtering target, and the distance between the target and substrate is many mean free paths—very small potential drops reach the substrate to achieve local conformality.

[0159] Fig. 24B Depicted are the corresponding snapshots of the plasma potential spatial distribution for a representative long-kick case, where the surface area of ​​the substrate is much larger than that of the sputtering target, as well as the vacuum chamber components are negligible, and the distance between the target and substrate is many mean free paths—a small potential drop reaches the substrate to achieve local conformality. Fig.24C Better conditions are illustratively depicted in , showing the spatial distribution of the plasma potential for a representative long-kick case, where the sputtering target is of the same order as the substrate area to be treated / coated with material from the sputtering target, the vacuum chamber components are negligible, and the distance between the target and the substrate is small—almost all of the potential drop occurs on the substrate to obtain good conformality of the plasma bombardment.

[0160] Fig.25A Illustrative depiction Fig.24A -C, the potential distribution for the long kick and its corresponding ion energy distribution function. The contribution of ions to the short kick and to the acceleration away from the dense magnetic region is not shown. These illustrations highlight the normal, abnormal and hindered glow discharge conditions encountered during the long kick phase. Fig.25B A diagram depicting the case where an additional active bias is applied to the substrate to obtain additional ion bombardment energy.

[0161] because The technology can conformally deposit high-quality thin and thick films on composite surfaces, thus separating the typically difficult and physically challenging process of RFQ blade tip alignment from the fabrication of the sealed RFQ cavity structure. Figure 5CDepicted exemplary prior art, the traditional method of assembling an RF LINAC structure is to fabricate an entire 3D cross-section cavity, such as a primary-secondary blade structure, for assembly. Typically very precise and complex construction procedures and machinery, such as a 5-axis or 6-axis CNC milling machine, are required. According to the present disclosure, the blade sections can be bonded to the RF cavity and then conformally coated. This staged method of manufacturing an RF LINAC allows for the use of cheaper manufacturing techniques and smaller sized components.

[0162] Fig.26 An example of a precision fixture that aids in aligning and spacing the RFQLINAC blades is illustratively depicted. The particle beam channel 26113 is defined by the relative positions of the accelerator blade tips, such as at Fig.26 Blade tips 26112 are positioned around a center point in a cross-sectional view provided. Each of the four blades (including, for example, blade 26101) is aligned and spaced by a precision fixture 26110 and secured to a mechanical support such as mechanical support 26111. Vertical, horizontal, angular, blade fluctuation, intra-blade capacitance, blade tip spacing, and other characteristics can be measured and controlled by removable fasteners or other mechanical means (such as pins, turnbuckles, shims, and spacers) that allow access to the blades without introducing additional degrees of freedom and error sources to the rest of the RF cavity structure. The precision alignment fixture 26110 additionally includes, for example, measurement slots and ports for performing diagnostics and inserting probes (e.g., optical, vibration, acoustic, electromagnetic, capacitance beads, hairpin probes, etc.). The precision alignment fixture 26110 can be made of a material different from the underlying blade 26101 material. Depending on the bonding method and processing conditions used to join the blade 26101 to the rest of the RF cavity 26100, the precision alignment fixture 26110 material can be selected based on CTE characteristics, stiffness, etc. to maintain the alignment and gap spacing of the blade tip 26112 during bonding to the RF cavity 26100.

[0163] The performance of RF accelerators depends largely on the electrical properties of the RF accelerator cavity. The electrical properties are affected by skin depth effects, surface roughness, grain size and boundaries, microcracks, electron transport and scattering effects of defects and inclusions, local permittivity, magnetic permeability and field diffusion. These properties can be measured by +Positive Kick TM and Super Kick TM The technology is modified to improve the intrinsic electrical characteristics. The external characteristics are affected by changes in cavity shape and blade tip position and alignment, affecting frequency, eigenmodes, dipole or higher order modes, etc. Combined with the macro shape, the changes are shape, interference, frequency, temperature, expansion effects and heat dissipation characteristics, surface roughness and retention capabilities and its electrical characteristics. The following describes Fig.27AA diagram of interface losses of adjacent RF surfaces and structures is illustratively depicted.

[0164] Fig.27A A cross-sectional view of an electrical component is depicted to illustratively depict the surface current path length, interface losses, and multi-factor stresses of adjacent RF surfaces and structures of conventionally processed materials, which result in relatively uneven outer conductive surfaces. Conventional room temperature RF LINACs use electropolished copper coatings or are machined from solid copper blocks to obtain the required / desired surface material properties. Wet chemical techniques for electropolishing and planarization vary based on the complex polar dynamics of conformal anode material structure, water flow, temperature, orientation of the etching / plating system, processing length, solution buffering, and high current bath power sources. Even using these techniques, conventional wet chemistry typically reaches surface roughness values ​​that exceed the skin depth of higher frequency microwave drivers, such as >500MHz. As a result, the skin depth current 26130 is very close to the surface. Because the skin depth current 26130 is carried near the surface within several skin depths, the effective current path length is significantly greater than the circumference of the RF cavity. This additional path length increases the effective resistance of the RF cavity, setting an upper limit on the cavity Q. The interfaces between different components and materials become more problematic for local electric fields and potential differences.

[0165] exist Fig.27A In the example of FIG. 2 , the undercut (gap) between the RF cavity sidewall 26100 and the blade 26101 adds additional path length (the distance added to the path entering and leaving the undercut (gap)). In addition, a potential difference will appear across the junction, resulting in the risk of multiple breakdown electron emission sites.

[0166] Fig.27B Illustrative depiction of the use +Positive Kick TM and Super Kick TM The surface current path length, interface losses and multi-factor stress of adjacent RF surfaces and structures produced by RF accelerator cavity surface treatment are reduced by the technology. The surface cleaning and etching process provides a flattening effect for high hills and allows re-sputtering to fill valleys. The deposition process allows injection / mixing to obtain boundary adhesion and strength of the final continuous conductive surface 26103, which can be deposited to the desired thickness by controlling film stress, nanostructure and orientation by sputtering / deposition using the sealing surface material deposition procedure described in this article. By adjusting the positive kick TM To obtain the best mobility of adsorbed atoms, the average roughness can be smaller than the skin depth. Depositing ultra-smooth surfaces. The resulting ultra-smooth surface path length approaches the ideal geometry for lower effective resistance. In addition, microcracks and surface interfaces are coated and covered by the continuous film 26103, minimizing the risk of multi-factor sites. The continuous film 26103 is selected from a variety of source / sputtering target materials, including superconducting materials, depending on the desired conductivity of the resulting cavity surface. The resulting continuous film 26103 increases the cavity Q to support higher acceleration gradients and / or reduce power consumption.

[0167] Fig.27C Illustrative depictions are of axial locations along the cavity having areas of poor electrical contact due to macroscopic effects such as bending stresses, thermal expansion, material mismatch, and poor mechanical RF seals at the interfaces. For RF LINACs of segmented or sectioned construction, mechanical fasteners 26114 are used to attach and compress the interfaces. RF compression seals are commonly used to achieve hard metal to metal contact, thereby minimizing electrical impedance. Unfortunately, the formation of macroscopic discontinuities 26115 results in uneven current flow in the RF cavity, lower Q performance, and variability in accelerator operating parameters. Ideally, the interface between the RF cavity 26100 and the blades 26101 is continuously fixed along the entire length of the accelerator cavity structure. This is typically achieved using high temperature brazing. Unfortunately, the electrical conductivity of the braze material is lower than that of the bulk alloy. In addition, thermal cycling of the RF LINAC has a significant impact on dimensional tolerances and stability. However, for the resulting continuous coating, the use of Technology eliminates added engineering costs and development.

[0168] like Fig.28 RF LINAC performance is further affected by the cross-sectional misalignment / positioning of the blades and the gaps between the blade ends, as shown in the illustrative cross section in Figure 1. Particle acceleration occurs as the particle undergoes quasi-continuous acceleration over the channel length formed by a set of blades at the center of the RF accelerator cavity. The alternating blade fluctuations change continuously as the particle velocity increases.

[0169] Fig.28 Highlights common blade misalignments in the critical blade tip region, which result in loss of beam transmission and very high electric fields in the gap, leading to sparking at the blade tip. Blade 26101 is positioned relative to the beam axis at the origin of the xy line. Basic misalignments include inline offsets along the x-axis 26122, y-axis 26121, and z-axis (not shown). Due to the introduction of misalignments (such as Fig.28As shown), the blade tips are no longer equidistant, which affects the intra-blade capacitance caused by gaps (such as gap 26120) in each quadrant. The varying capacitance affects the parallel impedance, electromagnetic power balance, and reduces the power injection efficiency of the accelerator. Overcoming signal degradation by increasing the input RF power increases the local electric field 26125 at the blade tip, thereby increasing the probability of a spark exceeding the critical field threshold. Misalignment and deformation due to heating can introduce distortions in the blades, such as the distortion misalignment on blade 26123, causing the surface normal of the blade tip to change and introducing additional edges to the local electric field 26125, resulting in the asymmetric focusing field of the quadrupole mode directing particles off-axis 26124. The net result of these effects is detuned RF cavity characteristics, lower cavity Q, increased risk of sparks, and lost beam transmission. Some of the adverse effects caused by blade misalignment can be compensated by increasing the RF power, higher blade tip voltage, longer LINAC cavity length to reduce overall gradients, etc. However, the precision alignment fixture discussed previously provides a means to mitigate blade misalignment, and Technology allows for continuous coating to reduce power consumption and / or reduce LINAC size, weight and power, i.e. RFQ LINAC System.

[0170] Fig.29 A low-Q cavity is graphically represented, which requires a high level of input RF power to meet the cavity energy storage threshold for particle acceleration and risk of blade tip electric field variation. In this representation, the cavity energy storage threshold 26117 is a function of LINAC parameters such as frequency, acceleration gradient, accelerator length, blade tip spacing and beam envelope, as well as the effective conductivity of the cavity, parallel impedance and the resulting Q factor. This is equivalent to the nominal blade tip electric field threshold 26117 for a perfectly aligned system. Variations in blade alignment will result in deviations from the optimal case at each position along the cavity, as well as suboptimal surface conductivity, increased path length, higher order modes and vector harmonics of cavity resonances. The resulting blade tip electric field distribution 26116 is shifted up to an elevated blade tip magnetic field distribution 26119 to achieve the threshold required for acceleration along the accelerator length. The cost is an increase in RF power 26118 to achieve the desired particle acceleration size. This comes at a cost because the peak blade tip electric field 26119 limits spark conditions and overall risk.

[0171] Fig.30 The high Q cavity is graphically illustrated by fabrication using the fabrication and surface treatment techniques described herein, including the use of a precision alignment fixture and forming a The resulting improved blade alignment accuracy and surface quality facilitates the production of RFQ accelerators that achieve lower RF power requirements and reduced blade tip variations to support higher axial acceleration gradients, resulting in overall compactness and power savings. With increased conductivity and reduced resistive losses, the higher cavity Q keeps the required cavity storage energy at a lower input RF power threshold of 26117, comparable to Fig.29 26126. The peak blade tip electric field 26119 is greatly reduced by an amount 26128 approaching the cavity threshold level 26117, with a well-regulated blade tip electric field distribution 26129. As shown in distribution 26129, the reduction in blade tip electric field variation allows for greater safety margins and relaxes the Kilpatrick limit for RF breakdown, thereby allowing higher acceleration gradients, wider operating frequencies, and beam configurations, such as achieving acceleration gradients of >4 MV / m, for reduced power, size, weight, and cost.

[0172] In general, the range of achievable accelerating gradients is limited by the arc / spark within the cavity itself. This is usually the dominant factor in determining the maximum electric field strength that can be sustained within the cavity. For example, the Kilpatrick criterion for breakdown-free operation is given by It specifies the maximum electric field in a 600MHz copper cavity structure (again, for no-breakdown operation) to be about 23MV / m. This is effectively a soft limit on the maximum electric field at the blade tip of the RFQ structure, with the so-called "bravery factor" (a multiple of the Kilpatrick criterion) typically being 1-2. As the electric field rises above this value, arcing may become increasingly frequent. Since the electric field is responsible for acceleration, this effectively limits the achievable acceleration gradient, which is in the range of Fig.30 The upper limit of the electric field at the blade tip is set in .

[0173] However, since arcing / sparking occurs almost exclusively at the blade tips in RFQ structures, where current is nearly zero, it is possible to 1) coat the blade tips with arc / spark resistant materials such as Be or TiN as a finishing step, or 2) have the arc / spark resistant material already present (either as a film coating or as bulk blade material itself), and then selectively apply a high conductivity coating everywhere except the blade tips, thereby achieving a high Q and arc / spark resistant overall structure. In short, the ability to utilize different materials for the cavity walls (where current is high) and the blade tips (where electric fields are high and arcing is a problem) allows arc confinement to be effectively decoupled from the material confinement of the high conductivity (Cu) cavity coating. The technology improves the smoothness of the blade tip surface to minimize local electric field concentration. However, the material purity of the coating, work function and field enhancement / secondary electron emission characteristics, coating morphology and nanostructure to minimize / suppress whisker growth and surface atomic mobility, and the elimination of inclusions and local field concentrators (such as particles and impurities found in traditional wet chemistry) are also the key factors influencing the process of the present disclosure. and deposition techniques are important variables to control.

[0174] The disclosure provided below is intended to enhance the above-mentioned devices and methods of operating these devices. More specifically, methods and devices capable of performing these methods are provided, which are based on the above-discussed Fig.16 , Fig.17A and Fig. 17B In the illustrative examples provided herein, the detailed timing diagrams include various specific forms of positive kicks, including specific modulations of timing, amplification, and polarity, which help achieve specific plasma dynamic effects for processing materials.

[0175] According to the disclosure below, the positive kick (referred to herein as the super kick) is modulated to achieve various (four) separate effects / results. First, the super kick is modulated to control / manipulate the diffuse plasma emitted from the magnetron target to generate additional plasma and free radicals for processing the substrate and / or the surrounding chamber. Second, the super kick is manipulated to control / modify the generation of high-energy ions that can etch substrates (such as, for example, glass, polymers, and ceramics). Third, the super kick is manipulated to achieve a first voltage value during the short kick phase and a second voltage value during the long kick phase. This control of the short kick and long kick phases is particularly suitable for operation of systems that require high-energy acceleration of metal ions from self-sputtering of a dense plasma confinement region near the target during the short kick phase, and then change to a low voltage during the long kick phase, where primarily argon ions will diffuse to the substrate and pass through the sheath, only to obtain this lower voltage value to achieve, for example, shot peening and densification without the need for argon injection. Fourth, the super-kick is manipulated to provide a super-kick before triggering the main negative pulse, thereby obtaining pre-ionization of particles in the magnetic trap to seed the plasma, thereby rapidly pulsing the plasma current and minimizing the turn-on jitter for process repeatability.

[0176] Go to Fig.31A , three main operating modes of Super Kick are provided. The first (top) waveform image illustratively depicts the main negative pulse that generates a HiPIMS-like discharge with a plasma current density exceeding (greater than) 0.03A / cm2 on the target area. The positive kick portion of the pulse waveform switches between a low positive voltage and an intermediate negative value at a configured modulation frequency. The switching frequency of the positive kick ranges from 0Hz (standard positive kick) to about 1MHz. The recommended switching frequency is in the range of 10kHz to several hundred kHz.

[0177] Continue to refer Fig.31A , the second (middle) waveform image includes a positive kick pulse, where the pulse is initially at a high positive voltage (e.g., about 500 volts), having the effect of accelerating metal ions from the near-target magnetic confinement region to the substrate during an initial short kick phase. Thereafter, the voltage is reduced to a lower (still positive) voltage value during a long kick phase. In the illustrative example, a two-step effect is shown that occurs after each main negative HiPIMS pulse. This positive kick (middle) waveform has been determined to effectively achieve metal implantation while minimizing argon implantation and defects in the surface film.

[0178] Finally, continue to refer to Fig.31A , the third (bottom) waveform image includes a positive kick pulse waveform determined to provide the desired results when performing etching. In this mode of operation, the voltage is modulated with a relatively high positive voltage so that during modulation, the waveform has a high voltage value that is typically greater than 300V and a low voltage that is slightly below zero volts. Modulating the pulse waveform signal in the third manner helps drive a RF-like discharge that is initially seeded with a dense HiPIMS plasma and then expanded and multiplied by the RF-like discharge from the magnetron target. The slightly negative lower voltage during modulation helps charge clear and refresh the surface for Fig.31A The next iteration of the positive kick pulse waveform is shown at the bottom. Depending on the frequency of the super kick, there will be a distribution of ion energies on the substrate. The side photo represents and demonstrates Fig.31A The wide variability in discharge type and quality for each of the three positive kick pulse waveforms depicted in .

[0179] Briefly go to Fig.31B , Fig.31A Each of the three positive kick pulse waveforms depicted in FIG. 1 shows exemplary maximum and minimum voltages for various modes of operation of the positive kick pulse. From left to right in this set of example waveforms, these modes are referred to as Aggressive Super Kick, Etch Super Kick, and Injection SK, respectively.

[0180] Fig.32 Prior art pulse waveforms for performing DC sputtering, pulsed DC, conventional HiPIMS with very long main negative pulses, and positive kick are summarized. The present disclosure relates to changes to the basic kick pulse to affect the plasma and the resulting deposition / etching functionality.

[0181] This is also beneficial to improving the reliability of the plasma process. Fig.33A, shows a conventional HiPIMS main negative pulse. At time t=0, the main voltage waveform 3300 is applied. The resulting current waveform 3301 requires an initial time 3302 to guide the plasma in the magnetron and increase the current density. As a result, there may be a turn-on jitter 3303, which may cause process variations. This turn-on jitter has previously been addressed by designing the power supply to provide an initial impact pulse at turn-on.

[0182] Fig.33B An illustrative waveform is shown with a shock pulse 3304 added to the beginning of the pulsed voltage waveform 3300. The amplitude of the shock pulse 3304 can be, for example, more than twice the size of the nominal operating condition, and therefore presents technical challenges to the operation of the HiPIMS device. By applying the shock pulse 3304, the high voltage causes a very steep bootstrap of the electrons in the magnetic trip, greatly accelerating the gas multiplication and ionization on the target to achieve higher densities and current ramps for self-sputtering. While the shock pulse 3303 may be relatively easy (conceptually) to implement, the introduction of this effect in the HiPIMS waveform can cause problems for targets that are dirty, require conditioning, or are of a material type that is prone to arcing. In this case, the shock pulse may have a detrimental effect due to the generation of particles and the formation of molten droplets, which is a curse for semiconductor manufacturing.

[0183] Fig.33C An illustrative waveform is provided that facilitates features such as providing the necessary preionization near the magnetron for current bootstrapping without requiring very high voltage surge pulses that are prone to arcing and droplet particle generation (see Fig.33B ).exist Fig.33C , a modulated super-kick pre-ionization pulse 3305 is applied immediately prior to the main negative voltage 3300 to achieve the high current densities of the HiPIMS. Through the properties of the magnetic field present around the magnetic trap, applying an RF-like oscillating voltage directly to the target electrode will cause the electrons to oscillate back and forth and gain energy to initiate the ionization cascade, thereby having the effect of "seeding" the plasma for this activity. This enables the current indicated by the current waveform 3301 to rise rapidly. Note that the pre-ionization pulse 3305 waveform can take a variety of forms, from an RF oscillating signal to a relatively simple application of a short negative voltage pulse of at least on the order of 100V to cause the electrons to cause impact ionization or Penning ionization within the magnetic trap. This allows for a sustained strike, especially for materials that are difficult to sputter and prone to arcing.

[0184] Go to Fig.34A, another exemplary positive kick pulse waveform is provided that incorporates the application of an RF-like positive kick pulse after terminating the main negative voltage waveform 3400. This RF-like application occurs on a super kick pulse envelope 3410. The duration of the envelope 3410 can be set to accommodate several RF cycles during the super kick portion of the waveform. There is a V_kick+ positive voltage 3406 and a V_kick- negative voltage 3407. The duration of the pulse width 3408 of the V_kick+ pulse is separately configured / established relative to the duration of the pulse width 3409 of the V_kick- pulse. Several RF-like oscillations occur within the envelope 3410. Fig.34A In the illustrative example of , the main negative pulse 3400 generates a dense HiPIMS plasma that exceeds the 0.03A / cm3 threshold. After the dense plasma is generated, it then diffuses toward the substrate. The positive width 3408 of V_kick+ is adjusted in conjunction with the adjustment of the negative width 3409 of Vkick- to produce different fluxes of ions and electrons to the substrate and different results. For substrates that are strong insulators, "charge removal" is very important to prevent cracking, prevent surface arcing, and minimize particle generation and defects. The V_kick+ rail voltage 3406 is set together with the opposite V_kick- rail voltage 3407 to define the upper and lower voltage boundaries of the envelope 3410 during the super kick operation. Note that the envelope of the super kick can have a relatively long duration. With a sufficient voltage difference between Vkick+ 406 and Vkick- 407, Fig.34A The signal modulation within the super kick envelope 3410 results in the generation of a quasi-RF-like discharge.

[0185] Go to Fig.34B , the Super Kick Envelope 3410 appears modulated again. However, unlike Fig.34A The voltage levels are all reduced compared to the voltage levels shown. In particular, the positive Vkick+ voltage is kept low to minimize the ion energy delivered to the substrate from Vkick+ 3406 (e.g., no greater than 100V). In addition, Vkick- 3407 is reduced to provide the required ~300V voltage difference between the high and low voltage levels (rails) of the super kick envelope 3410. With sufficient voltage difference between the positive and negative levels within the modulated signal within the envelope 3410, the RF-like nature of the electron motion can be maintained and the remote plasma is bootstrapped.

[0186] In operation, during the main pulse 3400, a plasma consisting of a working gas and sputtered material from a sputtering target is ionized to form a plasma. A bipolar super kick pulse follows in a super kick envelope 3410. The bipolar super kick pulse includes a series of voltage level modulations between a positive voltage level at Vkick+ 3406 and a negative voltage level or a smaller positive voltage level at Vkick- 3407, which ionizes the working gas and sputtered material, which has the additional effect of generating ionized and neutral free radicals. In the case of neutral free radicals, the free radicals diffuse to the substrate, or they can be accelerated by the positive potential applied during the bipolar super kick pulse train within the envelope 3410. In addition, during the super kick envelope 3410, the persistent plasma maintained by the modulated electric field produces a bipolar potential at a material boundary (such as a substrate), which also accelerates the ionized free radicals into the substrate. Furthermore, according to an illustrative example, the Vkick+ and Vkick- potentials can be modified in value and / or duration to not only generate plasma and free radicals, but also to control the average amount of current delivered to the substrate by the plasma according to the selected Vkick+ and Vkick- values. During deposition, the free radicals generated primarily regulate chemical reactions at the substrate plate, but also regulate chemical reactions in the gas phase.

[0187] Go to Fig.35A , an exemplary positive kick waveform is provided for processing insulating substrates that require deep etching. A main negative pulse 3500 is applied to generate a HiPIMS plasma with sufficient current density to achieve high plasma density and ionization fraction. For the very short duration of the main pulse 3500, the particle species produced will be mainly carrier gas, such as Ar. A super kick pulse is applied according to a super kick envelope 3510, where the positive voltage level is relatively very high for the VKick+ track 3506 over a pulse width 3508. The very positive voltage is commutated through the dense plasma in the target-substrate gap, and ultimately a sheath is generated on the substrate for high pressure ion bombardment. The high voltage ions have sufficient energy to induce etching on the substrate from ion energies of hundreds of eV. For insulating substrates, the surface can be charged to inhibit and repel future ion etching. However, during the period depicted by the pulse width 3509, this effect is countered by reducing the super kick voltage to the negative voltage potential of the negative track Vkick-3507 multiple times during the period of the super kick envelope 3510. The negative bias voltage (usually only tens to hundreds of volts) is sufficient to balance the surface charge with the bulk plasma, thus Fig.35A The next example of a positive super-kick pulse is depicted to prepare the substrate.

[0188] Since the superkick acts like an RF-like pulse, the effective ion energy to the substrate is modified by the effective frequency of the superkick pulse envelope 3510. Modulating the input voltage within the envelope 3510 at a sufficiently high frequency establishes an effective RF bias 3511. Fig.35B The effective ion energy 3512 is illustratively depicted for the case of low super kick frequency 3514 and high super kick frequency 3513. The low frequency case, typically in the range of 10-100 kHz, will produce an ion energy distribution 3514 with a peak energy 3506 defined by V_kick + higher orbit voltage, with ion energies in the middle 3511. For modulation of the voltage within the super kick envelope 3510 at higher repetition rates (e.g., greater than 200 kHz and up to the MHz range), the ion population in the plasma near the substrate becomes less responsive to the applied field with a slower transit time, causing the ion energy distribution function to become tighter and more centered in the bandwidth at half the value of V_Kick+ based on the difference between V-Kick+ 3506 and V_Kick- 3507.

[0189] After the main negative pulse 3500, an intermediate frequency pulse with a higher potential positive pulse is generated. Fig.35A As shown, a high voltage positive kick pulse for accelerating ions away from the sputtering target toward the substrate and an additional negative pulse at an intermediate potential between the short high kicks operate to modify the sputtering target surface by one or more of the following processes: neutralizing surface charge, implanting plasma ions into the surface, cleaning the surface, and generating plasma in the sputtering target-substrate gap to achieve plasma activation of the substrate, cleaning the substrate, implanting ion species in the substrate (including for generating pores), and ionizing / activating gas species and particles in the intermediate space. Independently controllable pulse widths between tracks allow selection and adjustment of any one or more of the target surface treatment processes listed above.

[0190] Go to Fig.36 , schematically depicting a non-RF-like application of a super kick for controlling the ion energy distribution of metal ions from a target and gas ions in a diffuse plasma. A main negative pulse 3600 is applied to generate a HiPIMS plasma with a suitable metal ion population in a magnetic trap region having a high density. The main pulse 3600 ends and immediately during a short kick phase 3615, a relatively very high positive voltage pulse of voltage level 3617 is applied for the duration of pulse width 3619, which causes the metal ions currently in the magnetic trap region to be accelerated to a substate having a relatively very high energy according to a relatively high voltage level 36117. During the short kick phase 3615, the very voltage, high energy short kick phase of the pulse primarily accelerates metal ions or high Me / Ar ratios towards the substrate. The injection of high energy metal ions in the substrate in turn results in collision cascades and efficient energy transfer to enter a wider area of ​​the structural zone map. With Fig.36 Operations performed in the manner outlined in are very effective for sub-planar processing of substrates, where energetic metal ions penetrate several atomic layers of the substrate and enter the sub-layers, where phase changes or desired material properties can be induced in these layers of the substrate. After completing the short kick phase 3615, the voltage of the super kick pulse is reduced to a relatively low, but still positive voltage level 3618 to reduce the positive voltage bias of the commutation to the diffuse plasma in contact with the substrate. At a relatively low voltage, the subsequent long kick phase 3616 is characterized by the acceleration of gas ions and some metal ions, which fall into the near-substrate plasma sheath. The long kick phase 3616 has a time period 3620, the duration of which is configured to enable the diffuse plasma to be reduced. The voltage level of the positive voltage level 3618 is adjusted to a level that minimizes or inhibits injection, allowing the Ar ions to provide surface mobility, densification, and thermal energy without causing defects or embedding Ar into gaps that may cause residual compressive stresses.

[0191] For the implantation and stress control super kick, a two-stage super kick pulse that is kept positive is used. As with other methods, the main pulse 3600 generates a dense plasma rich in sputtering target material. The high Vlick+ 3619 is typically short to accelerate only the ionized sputtering target material toward the substrate while minimizing the amount of working gas accelerated toward the substrate. The high energy ions are then implanted into the substrate surface, which can also promote mixing of the materials. The Vkick low voltage 3618 then accelerates the residual plasma (both ionized working gas and ionized sputtering material) toward the substrate. This generates a lower ion energy flux on the substrate, which can control film stress by modulating the surface mobility of adsorbed atoms.

[0192] Controlling the voltage level of the positive kick pulse to include a very high initial kick pulse voltage to inject ionized sputtered species, followed by a significantly lower voltage pulse between the main negative pulse and the kick pulse voltage, helps control one or more of the following: controlling film stress via lower energy ion bombardment (shot peening) to achieve stress control, porosity control, introduction of ionized gas species, substrate cleaning, and chemical reaction processes. The disclosed voltage level and duration control is also used to improve the conformality of the sputtered film by initially achieving a high ionization fraction of the sputtered atoms in flight, and then reducing the applied voltage to shrink the plasma sheath and reduce the possibility of re-sputtering of the substrate surface. In addition, maintaining a high ion fraction after the initial plasma formation main pulse allows bipolar diffusion to distribute the sputtered material more conformally than traditional PVD line-of-sight methods. In addition, the resulting increased low-energy bombardment has the effect of providing a controllable increase in the mobility of adatoms, which, depending on the material, allows control of film density and stress, as well as further increased conformality due to the reduction in sheath thickness.

[0193] Go to Fig.37A and Fig.37B, provides a combination of waveforms and illustrative depictions of the corresponding physical / electrical effects on magnetron sputtered structures, highlighting the above reference Fig.34A and Fig.34B Aspects of voltage / timing control of the super kick pulse discussed. The main negative HiPIMS pulse 3700 voltage applied to the magnetron target 3721 causes dense metal sputtering and plasma to be generated within the magnetic confinement region 3723. When the super kick pulse is at a high voltage 3706 of the positive track applied across the magnetic field, metal ions 3725 are generated and accelerated toward the substrate 3722. Dense plasma 3724 diffuses toward the substrate 3722 and produces a conformal sheath. After the main negative HiPIMS pulse 3700, the voltage between the negative track voltage 3707 and the positive track voltage 3706 is modulated within the envelope of the super kick pulse (at a sufficiently high frequency as discussed above) to generate additional plasma in the gap between the target 3721 and the substrate 3722. The positive track voltage 3706 biases the diffuse plasma 3724, which will obtain an RF bias that bombards the substrate 3722 with a low effective bias 3711. During the superkick operation phase, the combined effects of the RF superkick and plasma generation by RF-like electric field modulation generate additional radicals and ions 2726 near the substrate 3722. The radicals and ions are potentially beneficially used as: dopants, reactive gas bonding materials, and surface modifiers.

[0194] Like the "bipolar" super kick for free radical generation, the etch super kick uses a series of positive pulses 3506 after the main pulse 3500, and lower voltage or negative pulses 3507 between the positive super kick pulses. The positive and negative pulse structures in the super kick do not need to be symmetrical, which means that the width of the positive pulse 3508 can be different from the pulse width of the negative pulse 3509. For the etch super kick, a higher Vkick+ is selected so that the ions arrive at the substrate with sufficient energy to remove material via sputtering of the substrate. The return of the super kick voltage to a lower or negative potential generates a changing electric field and plasma formation, which is necessary to form ions for completing the etching. The size and width of the negative pulse 3509 can be used to control the starting position and type of ions accelerated toward the substrate. For example, a long negative Vkick-3507 may cause plasma formation to be primarily at the sputtering surface, so the starting position will be near the sputtering target surface. When the positive polarity reversal occurs, these ions are then accelerated away from the sputtering target, typically by electric field lines that are substantially perpendicular to the magnetic flow lines, resulting in a directed flux of ions toward the substrate surface, which can allow for deep trench etching / re-sputtering processes. The positive or, to a lesser extent, negative Vkick-3507 can play a complementary role by forming a plasma in the volume between the sputtering target and the substrate, producing a quasi-conformal flux of ions at the substrate surface. The negative portion of the superkick pulse can also regenerate near-surface species, such as oxides, on the sputtering target for sputtering during a subsequent main pulse.

[0195] In summary, the main negative pulse 3700 is followed by a super kick pulse characterized by a modulated voltage between relatively high and medium voltages, producing a series of RF-like voltage pulses of positive, negative, or both polarities to generate plasma and accelerate ion species into substrates and sputtering targets to achieve cleaning, ion implantation, surface porosity control, texturing, etching, charge neutralization, ion species reactions, and stress control. At sufficiently high modulation frequencies, the RF-like pulses generate plasma outside the magnetic confinement region 3723 to allow good conformality on all surfaces, even for insulating films that may be charged to high surface potentials under conventional sputtering conditions. In addition, Fig.37A The RF-like pulses within the super-kick envelope of the pulse generation scheme outlined in facilitate controlled addition of ion energy during reactive deposition by ensuring charge removal on the insulating substrate.

[0196] Similarly, refer to Fig.38A and Fig.38B, shows a relatively higher voltage, etching mode, super kick pulse operation by applying a high voltage 3806 after applying a main negative voltage HiPIMS pulse 3800 to form a plasma. The negative orbit voltage 3807 of the super kick pulse is a slightly negative voltage to induce a charge removal action on the substrate 3822 to prepare for the next wave of ion bombardment at an effective ion energy based on the repetition rate. The magnetic sub-target 3821 is pulsed with a negative electric field generated by the main negative voltage HiPIMS pulse 3800, and a dense plasma is generated in the magnetic confinement region 3823. For short main pulse widths, the gas ion concentration in the plasma will be high relative to the metal ion concentration, especially when the applied negative orbit voltage 3807 is below the self-sputtering threshold. In this case, the super kick pulse electric field engages and diffuses the dense plasma in the magnetic confinement region 3823 toward the target-substrate gap. As Fig.38A As shown in the depicted waveform, the superkick pulse track high voltage 3806 uses the charge balancing characteristics of the superkick-like RF response to generate an effective RF bias for etching on plastics, glass, and ceramics. The high-energy ions in the sheath region 3826 are accelerated into the substrate for etching.

[0197] Turning to FIG. 39 , yet another example for controlling the voltage of a positive kick pulse is provided to achieve specific characteristics of the resulting surface treatment operation. In the illustrative example, the process for metal ion energy control is quasi-independent from the generation of sputtering gas ions. In the illustrative example, a main negative HiPIMS pulse 3900 is applied to generate an electric field that engages and generates a dense and metal-dominated plasma from a target 3921 in a magnetic confinement region 3923. Metal ions 3955 are accelerated perpendicular to the gradient in the magnetic field 3927 by applying a fast positive kick at a high voltage 3917 to accelerate metal ions 3925 into a substrate 3922. The high voltage 3917 is applied during a relatively short kick period, and thereafter the voltage of the positive kick pulse is reduced to a relatively low voltage 3918, for a relatively long shot peening stage, in which the diffuse plasma 3924 expands to contact the substrate 3922, generating a quasi-conformal sheath on the surface of the substrate 3922, and accelerating lower energy carrier gas ions 3928 to provide energy to the substrate 3922 surface without damage.

[0198] Fig.40A is another illustration of a remote plasma generation process using a magnetron 4021 with a super kick power waveform provided by a pulse power module 4032. The diffuse plasma 4024 expands to interact with the substrate 4022 and the resulting thin film 4029 on the surface. Super kick voltage modulation controls the sheath 1030 voltage and ion energy and flux.

[0199] according to Fig.40BIn the process outlined in, the super kick rail voltage is increased to be very high, enabling etching of the film 4029 or substrate 4022 on the substrate from a diffuse plasma with a high pressure sheath 4031.

[0200] exist Fig.40C In the super kick pulse generation scenario, it is suitable to perform metal implantation, where ions are accelerated from the magnetron 4021 and travel through the chamber toward the substrate 4022 and the film 4029. The metal appears as an ion gun beam and / or has a very high sheath distance at the substrate because the plasma is not balanced during the short kick phase. Subsequently, a longer duration, relatively low voltage kick voltage sheath 4030 produces shot peening and densification, while deposition onto metals such as Ta is less problematic.

[0201] for Fig.40A In the radical super kick mode, typical set points are +100V kick positive, -300V super mid-rail, to drive an "RF-like" plasma with 300-400V "increments" at high frequencies of 0.01-1MHz. The positive voltage is limited to about +100V to avoid ion damage to the substrate, while still generating a large number of plasma radicals such as O, N, C, etc. This method was developed to generate additional plasma near the substrate in reactive applications, while still extracting a dense HiPIMS plasma from the main negative pulse and kicking it toward the substrate. The core of the technology is to drive an asymmetric pulsed DC / symmetric RF-like plasma at a frequency of about 0.1MHz to generate an extended plasma between the substrate and the target. The voltage difference is sufficient to maintain the plasma, but the energy is not enough to damage the sensitive substrate.

[0202] For Fig.40B In-situ deposition / etching of insulating substrate shown, dense HiPIMS plasma is generated by main negative pulse and thereafter ions are accelerated towards substrate by high positive kick voltage. Asymmetric pulsed DC / symmetric RF-like plasma is driven with modulation of about 0.1 MHz to generate extended plasma on substrate. High +V for Ar+ etch with -V voltage reversal for charge removal on insulating substrate. AC-Like Kick TM Allows Ar+ to bombard the substrate with high energy to perform direct etching.

[0203] for Fig.40CImplant / stress controlled super kick mode shown with typical values ​​of +400-600V kick positive and +20-50V mid rail. This maximizes metal ion implantation at the beginning and then shot peening is performed without Ar implantation to control stress. This technique was developed to implant only metal ions and maintain Ar shot peening during the "short kick" phase. During the positive kick pulse phase, the dense metal-rich HiPIMS plasma from the main negative pulse is kicked towards the substrate. The short high +V pulse portion of the positive kick pulse accelerates metal ions from the magnetic trap for implantation before the potential is reversed. Thereafter, the relatively long low +V portion of the positive kick pulse provides a conformal sheath around the substrate at low energy for shot peening without etching / implantation.

[0204] like Fig.41A As shown, a controllable power supply device for providing power via multiple discrete power supplies (rails). The device includes multiple rails, including a -V main negative rail 4134, a +kick positive rail 4137, and an intermediate super kick positive kick pulse rail, respectively -Vsk rail 4135 and +Vsk rail 4136. Parallel operation of semiconductor high voltage (HV) switches arranged in series for HV isolation 4138 is used to pulse each of the four voltage rails. The power supply can use isolated DC converters on the low side and high side, and a buck converter on the super kick rail.

[0205] Fig.41B Shown is a 3-track Fig.41A However, in the 3-track embodiment, the positive kick pulse is generated by the floating adjustable track 4140. In principle, Fig.41B The operation of the circuit is basically similar to Fig.41A operation of the device in.

[0206] The device can include multiple rails to get higher switching duty cycles. The setup can also be used for true bipolar operation where two magnetrons are running and one magnetron is used as the anode return path and the magnetrons flip / alternate to function. The switching topology is based on a platform with many discrete switches for speed, fast turn-off and excellent arc handling compared to monolithic bricks which have slow response times, low transition di / dt rates and problematic capture. The system can have many N-grade SiC switches / transistors operating in parallel to get TEMP, I_peak, I_avg, kHz. In one illustrative embodiment, the system has a fully adjustable super kick rail with a +1200V main negative kick and a +600V positive kick.

[0207] Each group of N-stage transistors 4138 Fig.41CDetailed further in the illustrative exemplary circuit diagram provided in . The input line from the energy storage capacitor 4145 feeds a plurality of parallel N-stage transistor switch stacks 4147. Each of the N-stage transistor switch stacks 4147 consists of 1 or more series connected transistors 4144 supported by a series transistor leveling and balancing circuit 4141 to achieve a high voltage switch interval to support the voltage difference between the energy storage capacitor 4145 and any other line voltage present on the output line of the output pulse track 4146. The output blocking diode 4143 has the appropriate polarity for positive or negative pulses from the parallel N-stage transistors 4138. The number of parallel stacks in 4138 is indicated by the label X or Y and can be as small as 1 to greater than 100. In one embodiment, there are 20 parallel N-stage transistors 4138 supporting the main negative rail 4134, 20 supporting the positive kick rail 1137, and 5 supporting each of the positive super kick rail 4137 and the negative super kick rail 4136.

[0208] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety herein.

[0209] Unless otherwise indicated herein or clearly contradictory to the context, the use of the terms "a", "an" and "the" and similar references in the context of describing the present invention (especially in the context of the following claims) should be interpreted as covering the singular and the plural. Unless otherwise indicated, the terms "comprising", "having", "including" and "comprising" should be interpreted as open terms (i.e., meaning "including but not limited to") unless otherwise indicated herein. Unless otherwise indicated herein, the recitation of the range of values ​​herein is intended only to be used as a shorthand method of individually referring to each individual value falling within the range, and each individual value is incorporated into the specification as if it were individually recited herein. Unless otherwise indicated herein or clearly contradictory to the context, all methods described herein can be performed in any suitable order. The use of any and all examples or exemplary language (e.g., "such as") provided herein is intended only to better illustrate the present invention and will not limit the scope of the present invention unless otherwise stated. No language in the specification should be interpreted as indicating that any unclaimed element is essential to the practice of the present invention.

[0210] Exemplary embodiments known to the inventor for implementing the present invention are described herein. After reading the foregoing description, variations of these embodiments may become apparent to those of ordinary skill in the art. The inventor expects that a skilled person will appropriately adopt such variations, and the inventor hopes that the present invention can be practiced in a manner different from that specifically described herein. Therefore, the present invention includes all modifications and equivalents to the subject matter described in the appended claims as permitted by applicable law. In addition, unless otherwise indicated herein or clearly contradictory to the context, any combination of the above elements in all possible variations thereof is included in the present invention.

Claims

1. A system comprising a controlled power source for generating electrical pulses for a plasma discharge source, the controlled power source comprising: Output pulse track; DC power supply; a storage capacitor coupled to the DC power supply, wherein the storage capacitor is configured to supply the following via corresponding power rails: Main negative rail voltage, positive kick rail voltage, and at least one intermediate rail voltage having a voltage amplitude between said main negative rail voltage and said positive kick rail voltage; A controlled pulse power transistor group comprising: a plurality of transistors interposed between the energy storage capacitor and the output pulse rail, and a transfer controller configured to control the transfer of power from the energy storage capacitor to the output pulse rail; wherein the transmission controller is configured to specify a positive kick pulse waveform according to a user specified input, and wherein the positive kick pulse waveform is defined by user-specified parameters that configure the operation of the plurality of transistors to control the timing and voltage of: the positive kick rail voltage; and The at least one intermediate rail voltage.

2. The system according to claim 1, further comprising: a vacuum apparatus comprising a sputtering magnetron and a target electrode connected to the output pulse track; substrate; Wherein, the controlled power supply is configured as: generating a high power pulsed plasma magnetron discharge by applying the main negative rail voltage to the target electrode; as well as After applying the negative pulse, a configurable positive kick pulse applied to the target electrode is generated by adjusting at least one pulse characteristic selected from the group consisting of: start delay, duration, pulse width, pulse amplitude, short kick and long kick timing, pulse envelope and frequency including its modulation.

3. The system according to claim 1, wherein: The controlled pulse power transistor group includes a number Y of transistor switch stacks that can be modulated to fire sequentially or in series to adjust one or more characteristics of the group consisting of: peak power transferred to the output pulse track, peak current, and pulse repetition frequency.

4. The system according to claim 3, wherein: Each of the Y transistor switch stacks comprises: N discrete transistors connected in series, and Leveling and balancing circuits.

5. The system according to claim 2, wherein: During operation, a super-kick mode for pre-ionization is used to generate an RF-like voltage waveform for the magnetron sputtering target to excite and fill electrons near the magnetron before the main negative DC pulse is started.

6. The system according to claim 2, wherein: During operation, a super-kick mode is selected for RF-like plasma maintenance and free radical generation at the substrate by controlled ion energy.

7. The system according to claim 2, wherein: During operation, the super kick mode was selected for etching.

8. The system according to claim 2, wherein: During operation, the super kick mode is selected for metal injection with the short kick and shot peening with the long kick.

9. The system according to claim 2, wherein: The energy distribution of ions directed to the substrate is controlled by adjusting the super kick orbit pulse modulation frequency, super kick orbit amplitude and positive orbit amplitude.

10. A method for providing a pulsed power waveform, the method being performed by a system comprising a controlled power supply for generating electrical pulses for a plasma discharge source, in, The controlled power supply comprises: Output pulse track; DC power supply; a storage capacitor coupled to the DC power supply, wherein the storage capacitor is configured to supply the following via corresponding power rails: Main negative rail voltage, positive kick rail voltage, and at least one intermediate rail voltage having a voltage amplitude between said main negative rail voltage and said positive kick rail voltage; A controlled pulse power transistor group comprising: a plurality of transistors interposed between the energy storage capacitor and the output pulse rail, and a transfer controller configured to control the transfer of power from the energy storage capacitor to the output pulse rail; wherein the transmission controller is configured to specify a positive kick pulse waveform according to a user specified input, and wherein the method includes operating the transmit controller according to the user-specified input to generate a positive kick pulse waveform defined by user-specified parameters, the user-specified parameters configuring the operation of the plurality of transistors to control the timing and voltage of: the positive kick rail voltage; and The at least one intermediate rail voltage.

11. A method for performing surface modification on a substrate by generating and controlling an ion flux for high power pulsed magnetron sputtering using a super kick mode, wherein: The method comprises: providing a vacuum apparatus including a sputtering magnetron and a target electrode connected to an output pulse track; providing a substrate having a surface to be modified by the method; generating a high power pulsed plasma magnetron discharge by applying the main negative rail voltage amplitude to the target electrode; and After terminating the negative DC pulse, a configurable super-kick pulse waveform is generated for the magnetron target electrode to achieve a super-kick mode, wherein the configurable super kick pulse is performed using capacitive stored power delivered through one or more pulsed power transistor groups to supply positive voltage, negative voltage, or both, Wherein, during said generating, the control signal is used to adjust at least one super kick pulse characteristic selected from the group consisting of: start delay, duration, pulse width, pulse amplitude, short kick and long kick timing and frequency including modulation thereof.

12. The method according to claim 11, further comprising: configuring the super kick mode for enhanced plasma generation in a target-substrate region with minimal substrate damage from ion energy; Configuring the positive kick track to be within the range of positive 10-100V; Configuring the negative super kick rail to be within the range of negative 200-300V; The positive kick and negative super kick pulse periods are configured to be 5-50us; The super kick pulse envelope is configured to have a duration of 100-500us; and, Therein, the substrate surface is further modified by plasma bombardment.

13. The method according to claim 11, further comprising: configuring the super kick mode for etching a substrate with enhanced ion energy; Configuring the positive kick track to be within the range of positive 400-600V; configuring the negative super kick rail to be within the range of negative 10 to 100 V; The positive kick and negative super kick pulse periods are configured to be 5-20us; The super kick pulse envelope is configured to have a duration of 100-1000us; and, Therein, the substrate surface is further modified by plasma bombardment.

14. The method according to claim 11, further comprising: The super kick mode is configured for metal ion implantation with a short kick and surface shot peening and densification with a long kick; Configuring the positive kick track to be within the range of positive 400-600V; configuring the positive super kick rail to be within the range of negative 10 to 50 volts; The positive kick pulse width is configured to be 5-20us; The positive super kick pulse width is configured to have a duration of 20-200us; Therein, the substrate surface is further modified by plasma bombardment.

15. The method according to claim 11, further comprising: configuring the super kick mode for performing deep metal ion implantation with a short kick and performing enhanced plasma generation in a target-substrate region with minimal substrate damage from ion energy; Configuring the positive kick track to be within the range of positive 400-600V; The positive kick pulse width is configured to be 5-20us; configuring the positive super kick rail to be within the range of positive 10-100V; Configuring the negative super kick rail to be within the range of negative 200-300V; The positive kick and negative super kick pulse periods are configured to be 5-50us; The super kick pulse envelope is configured to have a duration of 100-500us; and, Therein, the substrate surface is further modified by plasma bombardment.

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