Patent Description:
Plasmas are ionized gases that may be created by a variety of methods. One way of creating plasmas is by using electromagnetic energy to ionize a gas. Plasmas may conduct electricity and interact with electromagnetic radiation. Acoustic sources produce pressure waves in a medium through which acoustic waves travel, such as a solid, liquid, or gas. These pressure waves may change the local density of the material through which the acoustic waves travel.

Metamaterials are manmade materials having properties not normally found in nature. For example, some metamaterials display a negative index of refraction. Many metamaterials are constructed from multiple elements of composite materials arranged in a repeating pattern or structure. The elements of a metamaterial are generally smaller than the wavelength of the phenomena a metamaterial influences. For example, a metamaterial acting as an optical wave guide may have a pattern made of elements smaller than the wavelength of light which interacts with the metamaterial.

<CIT> describes a method of prevention of plasma contamination in a plasma reactor system comprising applying electrostatic, electromagnetic, mechanical, thermal, pressure, hygroscopic or chemical means to eliminate particle contamination in situ in said plasma reactor system, as well as corresponding apparatus.

<CIT> describes a system and method for harmonic modulation of standing wavefields for spatial focusing, manipulation, and patterning of particles, cells, powders, aerosols, colloids, and solids using a multifrequency wave source, a chamber, a control module and an analysis module to generate standard wavefields useful for tissue engineering, micro fabrication, therapeutic treatment, and diagnostic tests.

<CIT> describes a plasma etching device which is used, in particular, for dry etching of a wafer and which makes use of a device for generating a standing sound wave in the plasma in order to achieve an increased etching rate in conjunction with increased anisotropy.

<CIT> describes an acoustically enhanced deposition processes, and a system for performing the same. In one embodiment, the method comprises providing a substrate having a layer of insulating material formed there above, the layer of insulating material having a plurality of openings formed therein, performing a deposition process to form a layer of metal at least in the openings in the layer of insulating material, and actuating at least one acoustic generator to generate sound waves during the deposition process.

According to a first aspect of the invention, there is provided an apparatus for producing a plasma having a three dimensional shape, as defined in claim <NUM>. Optional and/or preferable features are set out in dependent claims <NUM>-<NUM>.

According to a second aspect of the invention, a method is provided for producing a three dimensional shape in a plasma, as defined in claim <NUM>. Optional and/or preferable features are set out in dependent claims <NUM>-<NUM>.

Technical advantages of certain embodiments may include creating a plasma with properties of a metamaterial that may replace solid metamaterials in certain applications. Additionally, certain embodiments may include creating a plasma that may be formed into a varying metamaterial, allowing the properties of the plasma metamaterial to be varied in time and space. In certain embodiments, a plasma may be formed into an arbitrary three dimensional shape. Such a shape may be placed in contact with a complex object to apply a coating or to etch certain areas of the object, in some embodiments.

To provide a more complete understanding of the present invention and the features and advantages thereof, reference is made to the following description taken in conjunction with the accompanying drawings, in which:.

Examples of the present invention and its advantages are best understood by referring to <FIG> of the drawings, like numerals being used for like and corresponding parts of the various drawings.

Acoustic waves applied to gases may change the pressure and density of gases in localized areas. By applying acoustic waves from more than one source, a standing wave pattern may be created in the gas, due to interactions between the acoustic waves, forming areas of higher pressure and density and lower pressure and density. In some examples, the acoustic waves may be high intensity ultrasonic waves. In other examples, the acoustic waves may be audible to the human ear. In other examples, the acoustic waves may be infrasonic acoustic waves, having a frequency lower than the human ear can detect. In some examples, the acoustic waves may have any frequency and any intensity.

A plasma is an ionized gas. The charge density of a plasma is dependent upon the background neutral pressure of the gas and the coupling of the input energy. Areas of different neutral pressure may have different plasma densities. In some examples, areas of increased neutral density may have increased plasma density. In other examples areas of decreased neutral density may have increased plasma density. The operational regime may be determined by one or more of the neutral-electron mean free path, the electron-ion recombination length, and the ion-neutral mean free path.

<FIG> illustrates an example of a plasma shaped in two dimensions by acoustic waves. In the illustrated example, acoustic sources <NUM> produce acoustic waves <NUM>. Acoustic waves <NUM> may be high intensity ultrasonic waves. Acoustic waves <NUM> may be audible to the human ear. Acoustic waves <NUM> may be infrasonic acoustic waves, having a frequency lower than the human ear can detect. Acoustic waves <NUM> may have any frequency and any intensity.

Acoustic waves 120A produced by acoustic source 110A may interact with acoustic waves 120B produced by acoustic source 110B. Interaction between acoustic waves 120A and acoustic waves 120B may create density fluctuations in a fluid, such as a gas or plasma, through which acoustic waves 120A and 120B propagate. Interaction between acoustic waves 120A and acoustic waves 120B may create a standing wave pattern with areas having higher density and areas having lower density in the fluid through which the acoustic waves <NUM> pass. These areas of higher density and lower density may be configured by adjusting acoustic waves 120A and acoustic waves 120B produced, respectively, by acoustic source 110A and acoustic source 110B. Configuration of the high density areas and low density areas may allow a gas or plasma to be fashioned into a shape, with a greater amount of plasma in regions determined by the neutral pressure profile. For example, a higher density areas of plasma <NUM> may be configured to have a shape as shown in <FIG> by an interaction between acoustic waves 120A and acoustic waves 120B.

Any number of acoustic sources may be used to produce acoustic waves. A greater number of acoustic sources <NUM> may allow for more complex shapes to be created by enabling complex interactions between acoustic waves <NUM> produced by multiple acoustic sources <NUM>. <FIG> illustrates an example in two dimensions, with two acoustic sources in the plane illustrated. However, it should be noted that acoustic waves propagate in three dimensions in a fluid, and the shape of plasma <NUM> may be affected by acoustic waves produced by acoustic sources not shown in <FIG>. For example, acoustic sources located above or below the plane illustrated by <FIG> may affect the shape of plasma <NUM>.

Acoustic sources <NUM> may be variable so as to produce variable acoustic waves <NUM>. Acoustic sources <NUM> may be capable varying the frequency and amplitude of acoustic waves <NUM>. Varying acoustic waves <NUM> may cause the standing wave pattern created by the interaction of acoustic waves <NUM> to change, thereby causing the shape of plasma <NUM> to change. By controlling acoustic waves <NUM> they shape of plasma <NUM> may be controlled.

<FIG> illustrates a plasma shaped in three dimensions by acoustic waves and an apparatus <NUM> for shaping the plasma, according to certain examples. In a similar manner to the example illustrated by <FIG>, acoustic sources <NUM> produce acoustic waves, similar to acoustic waves <NUM>. Acoustic waves are not illustrated in <FIG> for simplicity. In some examples, the acoustic waves may be high intensity ultrasonic waves. In other examples, the acoustic waves may be audible to the human ear. In other examples, the acoustic waves may be infrasonic acoustic waves, having a frequency lower than the human ear can detect. In some examples, the acoustic waves may have any frequency and any intensity.

Acoustic waves produced by each acoustic source <NUM> may interact, resulting in a standing wave pattern with areas of higher density and lower density. These interactions may be used to shape a fluid, such as a gas or a plasma. In the illustrated example, a plasma <NUM> is shaped into a torus by acoustic waves produced by acoustic sources <NUM>. In other examples, plasma <NUM> may be shaped into any shape by acoustic waves produced by acoustic sources <NUM>. Areas of high plasma density <NUM> and areas of low plasma density <NUM> may result from interactions of acoustic waves produced by acoustic sources <NUM>. In some examples, the density of plasma <NUM> may be continuously variable throughout plasma <NUM> according to interactions between acoustic waves produced by acoustic sources <NUM>. In certain examples, areas of low plasma density <NUM> may have a density so low as to be negligible (e.g., resulting in a permittivity very close to vacuum permittivity for a specified frequency).

In some examples, acoustic sources <NUM> may be affixed to the interior of a chamber <NUM>. Chamber <NUM> may have any shape and may contain plasma <NUM>. Chamber <NUM> may also have an energy source <NUM>. Energy source <NUM> may provide energy to ionize a gas contained in chamber <NUM>, resulting in a plasma <NUM>. In some examples, energy source <NUM> may be a radio frequency (RF) source. In other examples, energy source <NUM> may be a high power microwave source. In other examples, energy source <NUM> may be an electron beam. In some examples, chamber <NUM> may have more than one energy source <NUM>.

In some examples, chamber <NUM> may include a computer system <NUM> that controls the shaping of plasma <NUM> by providing instructions to the elements of chamber <NUM>, such as acoustic sources <NUM> and energy source <NUM>. In some examples, computer system <NUM> may provide instructions based on inputs computer <NUM> receives from sensors <NUM> located on or in chamber <NUM>. Sensor <NUM> may include any type of sensor, including but not limited to temperature sensors, acoustic sensors, visible light sensors or cameras, capacitive sensors, inductive sensors, pressure sensors, or any other type of sensor. Computer system <NUM> may be either external to chamber <NUM> or incorporated into chamber <NUM>. Certain examples of computer system <NUM> are discussed in more detail below with respect to <FIG>.

In some examples, the interior of chamber <NUM> may be held at a pressure greater than or equal to <NUM> pascal (<NUM> millitorr (mTorr)), and less than or equal to <NUM> pascal (<NUM> torr). In some examples, plasma <NUM> contained in chamber <NUM> may have a density high enough to sufficiently modify the permittivity for a given electromagnetic frequency as compared to vacuum permittivity.

Plasma <NUM> may be shaped into a metamaterial by interaction of acoustic waves from acoustic sources <NUM>, in some examples. Metamaterial plasma <NUM> may be shaped to have a repeating pattern or structure that effects how non-ionizing electromagnetic radiation interacts with plasma <NUM>. Metamaterial plasma <NUM> may be a three dimensional metamaterial having a pattern or structure that repeats in three dimensions. In some examples, a three dimensional metamaterial plasma <NUM> have a pattern or structure that varies between each axis of its three dimensional structure. For example, a plasma metamaterial could be created by shaping plasma <NUM> to interact with certain frequencies of electromagnetic radiation, such as microwaves or radio waves. Examples of interactions between non-ionizing electromagnetic radiation and plasma <NUM> that may be desirable include shaping plasma <NUM> to bend, focus, or steer radio waves. Other examples of interactions between non-ionizing electromagnetic radiation and plasma <NUM> that may be desirable include shaping plasma <NUM> to act as a filter to pass only certain frequencies of electromagnetic waves, or to act as a prism to split apart different frequencies of electromagnetic waves. In certain examples, plasma <NUM> may be shaped to have properties similar to a photonic crystal, which may enable plasma <NUM> to be used as a waveguide or as the whole or a portion of a nonlinear optical device.

In some examples, the properties of plasma <NUM> shaped into a metamaterial may be varied by varying acoustic waves emitted by acoustic sources <NUM> and by varying the energy emitted by energy source <NUM>. By changing the frequency or amplitude of acoustic waves emitted from each acoustic source <NUM>, the properties of a plasma metamaterial <NUM> may be changed by changing the structure of plasma <NUM> caused by the standing wave pattern created by the interaction of acoustic waves produced by each acoustic source <NUM>. By changing the energy emitted by energy source <NUM>, the density of a plasma metamaterial <NUM> may be changed. For example, the index of refraction or the frequency of electromagnetic radiation with which plasma metamaterial <NUM> may interact may be changed by changing the energy emitted by energy source <NUM>. The structure and function of the plasma metamaterial <NUM> may be changed by changing the acoustic waves produced by each acoustic source <NUM>.

In other examples, an object may be placed in contact with plasma <NUM>. In such examples, plasma <NUM> may act on the surface of the object in a variety of ways. Examples of how a plasma may interact with an object placed in contact with the plasma include applying a coating to surfaces of the object with which plasma <NUM> is in contact, or etching the surface of an object with which plasma <NUM> is in contact. For example, by shaping a plasma used in processes such as plasma vapor deposition or plasma polymerization with acoustic waves produced by acoustic sources <NUM>, the plasma could be shaped to contact only certain areas of an object placed in chamber <NUM>.

In some examples, plasma formation and shaping inside of chamber <NUM> may be controlled by computer system <NUM>. Computer system <NUM> may be any suitable computer system in any suitable physical form. In general, computer system <NUM> may store one or more digital representations desired shape and properties, such as temperature and density, of plasma <NUM> and provide chamber <NUM> with information to form and shape plasma <NUM>. For example, computer system <NUM> may store a mathematical model of plasma <NUM> and provide instructions to acoustic sources <NUM> and energy sources <NUM> of chamber <NUM> based on measurements from sensors <NUM> to form and shape plasma <NUM>.

Computer system <NUM> may be integrated into chamber <NUM>, connected to chamber <NUM>, or be multiple computer systems both integrated into chamber <NUM> and separate from chamber <NUM>. As an example and not by way of limitation, computer system <NUM> may be a virtual machine (VM), an embedded computer system, a system-on-chip (SOC), a single-board computer system (SBC) (e.g., a computer-on-module (COM or a system-on-module (SOM)), a desktop computer system, a laptop or notebook computer system, a mainframe, a mesh of computer systems, a server, an application server, or a combination of two or more of these. Where appropriate, computer system <NUM> may include one or more computer systems <NUM>; be unitary or distributed; span multiple locations; span multiple machines; or reside in a cloud, which may include one or more cloud components in one or more networks. A particular example of computer system <NUM> is described in more detail below in reference to <FIG>.

<FIG> illustrates an object <NUM> placed in contact with plasma <NUM>, according to certain examples. In the illustrated example, plasma <NUM>, formed into a torus, contacts object <NUM> at points of intersection <NUM> where the plasma torus <NUM> intersects object <NUM>. In the illustrated example, this intersection is two circles on each side of plate shaped object <NUM>. However, plasma <NUM> may be shaped into any arbitrary structure by acoustic waves generated by acoustic sources <NUM>, and therefore could be shaped to contact a complexly shaped object <NUM> at any number of desired areas.

In certain examples plasma <NUM> may be configured to apply a coating at points of intersection <NUM> with object <NUM>. For example, by plasma vapor deposition or plasma polymerization. In other examples, plasma <NUM> may be configured to etch object <NUM> at points of intersection <NUM>.

<FIG> illustrates an example in which non-ionizing electromagnetic radiation <NUM> is directed into plasma <NUM> after the plasma has been formed. Non-ionizing electromagnetic radiation <NUM> may be any form of electromagnetic energy, including but not limited to, radio waves, microwaves, infrared light, or visible light. In certain embodiments, plasma <NUM> may be shaped as a metamaterial and configured to steer or focus non-ionizing electromagnetic radiation <NUM> applied to plasma <NUM>.

In the embodiment illustrated in <FIG>, plasma <NUM> is shaped to steer non-ionizing electromagnetic radiation <NUM> at a <NUM> degree angle to the direction from which non-ionizing electromagnetic radiation <NUM> enters into plasma <NUM>. In this embodiment, non-ionizing electromagnetic radiation <NUM> exiting plasma <NUM> is illustrated as non-ionizing electromagnetic radiation <NUM>. In other embodiments, plasma <NUM> may be shaped into a metamaterial capable of steering non-ionizing electromagnetic radiation <NUM> at any angle. In other embodiments plasma <NUM> may be shaped into a metamaterial capable of focusing non-ionizing electromagnetic radiation <NUM> in a manner similar to a lens or series of lenses. In yet other embodiments, plasma <NUM> may be shaped into a metamaterial capable of separating different frequencies of non-ionizing electromagnetic radiation <NUM> in a manner similar to a prism or a filter.

<FIG> illustrates an example computer system <NUM>. Computer system <NUM> may be utilized by computer system <NUM> of <FIG>. In particular embodiments, one or more computer systems <NUM> perform one or more steps of one or more methods described or illustrated herein. In particular embodiments, one or more computer systems <NUM> provide functionality described or illustrated herein. In particular embodiments, software running on one or more computer systems <NUM> performs one or more steps of one or more methods described or illustrated herein or provides functionality described or illustrated herein. Particular embodiments include one or more portions of one or more computer systems <NUM>. Herein, reference to a computer system may encompass a computing device, and vice versa, where appropriate. Moreover, reference to a computer system may encompass one or more computer systems, where appropriate.

As example and not by way of limitation, computer system <NUM> may be an embedded computer system, a system-on-chip (SOC), a single-board computer system (SBC) (such as, for example, a computer-on-module (COM) or system-on-module (SOM)), a desktop computer system, a laptop or notebook computer system, an interactive kiosk, a mainframe, a mesh of computer systems, a mobile telephone, a personal digital assistant (PDA), a server, a tablet computer system, or a combination of two or more of these.

In particular embodiments, processor <NUM> includes hardware for executing instructions, such as those making up a computer program. As an example and not by way of limitation, to execute instructions, processor <NUM> may retrieve (or fetch) the instructions from an internal register, an internal cache, memory <NUM>, or storage <NUM>; decode and execute them; and then write one or more results to an internal register, an internal cache, memory <NUM>, or storage <NUM>. In particular embodiments, processor <NUM> may include one or more internal caches for data, instructions, or addresses. This disclosure contemplates processor <NUM> including any suitable number of any suitable internal caches, where appropriate. As an example and not by way of limitation, processor <NUM> may include one or more instruction caches, one or more data caches, and one or more translation lookaside buffers (TLBs). Instructions in the instruction caches may be copies of instructions in memory <NUM> or storage <NUM>, and the instruction caches may speed up retrieval of those instructions by processor <NUM>. Data in the data caches may be copies of data in memory <NUM> or storage <NUM> for instructions executing at processor <NUM> to operate on; the results of previous instructions executed at processor <NUM> for access by subsequent instructions executing at processor <NUM> or for writing to memory <NUM> or storage <NUM>; or other suitable data. The data caches may speed up read or write operations by processor <NUM>. The TLBs may speed up virtual-address translation for processor <NUM>. In particular embodiments, processor <NUM> may include one or more internal registers for data, instructions, or addresses. This disclosure contemplates processor <NUM> including any suitable number of any suitable internal registers, where appropriate. Where appropriate, processor <NUM> may include one or more arithmetic logic units (ALUs); be a multi-core processor; or include one or more processors <NUM>. Although this disclosure describes and illustrates a particular processor, this disclosure contemplates any suitable processor.

In particular embodiments, memory <NUM> includes main memory for storing instructions for processor <NUM> to execute or data for processor <NUM> to operate on. As an example and not by way of limitation, computer system <NUM> may load instructions from storage <NUM> or another source (such as, for example, another computer system <NUM>) to memory <NUM>. Processor <NUM> may then load the instructions from memory <NUM> to an internal register or internal cache. To execute the instructions, processor <NUM> may retrieve the instructions from the internal register or internal cache and decode them. During or after execution of the instructions, processor <NUM> may write one or more results (which may be intermediate or final results) to the internal register or internal cache. Processor <NUM> may then write one or more of those results to memory <NUM>. In particular embodiments, processor <NUM> executes only instructions in one or more internal registers or internal caches or in memory <NUM> (as opposed to storage <NUM> or elsewhere) and operates only on data in one or more internal registers or internal caches or in memory <NUM> (as opposed to storage <NUM> or elsewhere). One or more memory buses (which may each include an address bus and a data bus) may couple processor <NUM> to memory <NUM>. Bus <NUM> may include one or more memory buses, as described below. In particular embodiments, one or more memory management units (MMUs) reside between processor <NUM> and memory <NUM> and facilitate accesses to memory <NUM> requested by processor <NUM>. In particular embodiments, memory <NUM> includes random access memory (RAM). This RAM may be volatile memory, where appropriate. Where appropriate, this RAM may be dynamic RAM (DRAM) or static RAM (SRAM). Moreover, where appropriate, this RAM may be single-ported or multi-ported RAM. This disclosure contemplates any suitable RAM. Memory <NUM> may include one or more memories <NUM>, where appropriate. Although this disclosure describes and illustrates particular memory, this disclosure contemplates any suitable memory.

In particular embodiments, communication interface <NUM> includes hardware, software, or both providing one or more interfaces for communication (such as, for example, packet-based communication) between computer system <NUM> and one or more other computer systems <NUM> or one or more networks. As an example and not by way of limitation, communication interface <NUM> may include a network interface controller (NIC) or network adapter for communicating with an Ethernet or other wire-based network or a wireless NIC (WNIC) or wireless adapter for communicating with a wireless network, such as a WI-FI network. This disclosure contemplates any suitable network and any suitable communication interface <NUM> for it. As an example and not by way of limitation, computer system <NUM> may communicate with an ad hoc network, a personal area network (PAN), a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), or one or more portions of the Internet or a combination of two or more of these. One or more portions of one or more of these networks may be wired or wireless. As an example, computer system <NUM> may communicate with a wireless PAN (WPAN) (such as, for example, a BLUETOOTH WPAN), a WI-FI network, a WI-MAX network, a cellular telephone network (such as, for example, a Global System for Mobile Communications (GSM) network), or other suitable wireless network or a combination of two or more of these. Computer system <NUM> may include any suitable communication interface <NUM> for any of these networks, where appropriate. Communication interface <NUM> may include one or more communication interfaces <NUM>, where appropriate. Although this disclosure describes and illustrates a particular communication interface, this disclosure contemplates any suitable communication interface.

The components of computer system <NUM> may be integrated or separated. In some embodiments, components of computer system <NUM> may each be housed within a single chassis. The operations of computer system <NUM> may be performed by more, fewer, or other components. Additionally, operations of computer system <NUM> may be performed using any suitable logic that may comprise software, hardware, other logic, or any suitable combination of the preceding.

<FIG> illustrates a method <NUM> for forming and shaping a plasma, according to certain embodiments. Method <NUM> may be carried out by an apparatus for containing, forming, and shaping a plasma, such as apparatus <NUM> of <FIG>. Method <NUM> begins at step <NUM>, where a chamber, such as chamber <NUM> of <FIG>, is filled with a gas. At step <NUM>, chamber <NUM> may be filled with a gas to a desired pressure. In some embodiments, the interior of chamber <NUM> may be filled to a pressure greater than or equal to <NUM> pascal (<NUM> millitorr (mTorr)) and less than or equal to <NUM> pascal (<NUM> torr) at step <NUM>.

At step <NUM>, electromagnetic radiation may be applied to the gas occupying chamber <NUM> to ionize the gas, forming a plasma. In some embodiments, electromagnetic radiation may be supplied by an energy source such as energy source <NUM> of <FIG>. In some embodiments, the electromagnetic energy applied to the gas may be radio frequency (RF) energy. In other embodiments, the electromagnetic energy applied to the gas may be may be high energy microwave radiation. In other embodiments, the electromagnetic energy applied to the gas may be an electron beam. In some embodiments, the electromagnetic energy may be applied to the gas from more than one source or from multiple directions.

After the plasma has been formed at step <NUM>, acoustic waves may be applied to the plasma at step <NUM>. The acoustic waves may be generated by a plurality of acoustic sources <NUM> as illustrated in <FIG>. Application of acoustic waves to the plasma may form the plasma into a shape. Acoustic waves produced by each acoustic source <NUM> may be configured to produce a standing wave pattern when the acoustic waves interact with each other. This standing wave pattern shapes the plasma and may cause the plasma to form a shape having areas of higher density and areas of lower density.

In some embodiments, the acoustic waves may be tuned so as to create a plasma having the properties of a metamaterial.

Step <NUM> may occur prior to step <NUM>, in certain embodiments. Acoustic waves may be applied to the gas inside of chamber <NUM> prior to a plasma being formed at step <NUM>. In such embodiments, the acoustic waves applied at step <NUM> may shape the neutral gas into the desired shape prior to ionization and formation of the plasma at step <NUM>.

At step <NUM>, the apparatus for producing and shaping the plasma may determine if the plasma has reached the desired shape. If the plasma has not reached the desired shape, one or more acoustic sources <NUM> may alter the acoustic waves being produced to induce a change in the shape of the plasma. For example, computer system <NUM> of <FIG> may use information obtained from sensors <NUM> to determine of plasma <NUM> has reached a desired shaped. If computer system <NUM> determines that plasma <NUM> has not reached the desired shape, or deviates from the desired shape by a specified amount, then computer system <NUM> may instruct one or more acoustic sources <NUM> to change the acoustic waves those acoustic sources are producing.

In some embodiments, the acoustic sources <NUM> may constantly alter acoustic waves in order to maintain a shape in the plasma, as the plasma may naturally dynamically change shape. In some embodiments, the acoustic waves may be altered based on the plasma's deviation from a desired shape using a feedback loop controlled by computer <NUM>. In certain embodiments, the acoustic waves may be altered to change the shape of the plasma from a first shape to a second desired shape. When the plasma has reached its desired shape, the acoustic waves may be maintained at a constant level until the plasma deviates from the desired shape by a set amount, in certain embodiments.

In some embodiments, at step <NUM>, an object may be placed in contact with the plasma maintained in step <NUM>. For example, an object such as object <NUM> of <FIG> may be placed in contact with plasma <NUM>. Plasma <NUM> may be configured to apply a coating to object <NUM> or may be configured to etch object <NUM>. In some embodiments, the object may be placed in chamber <NUM> prior to formation and shaping of plasma <NUM> at step <NUM> and step <NUM>.

At step <NUM>, non-ionizing electromagnetic radiation is applied to the plasma maintained at step <NUM>. For example, if plasma <NUM> is shaped as a metamaterial, radio frequency waves applied to plasma <NUM> may be guided or focused by plasma <NUM> at step <NUM> as illustrated in <FIG>.

Modifications, additions, or omissions may be made to the methods described herein without departing from the scope of the invention. For example, the steps may be combined, modified, or deleted where appropriate, and additional steps may be added. Additionally, the steps may be performed in any suitable order without departing from the scope of the present disclosure.

Claim 1:
An apparatus (<NUM>) for producing a plasma (<NUM>) having a three dimensional shape comprising:
a chamber (<NUM>) filled with a gas;
a first energy source (<NUM>) operable to provide energy to ionize the gas in the chamber to form a plasma;
a plurality of sensors (<NUM>) operable to measure one or more properties of the plasma; and
a plurality of acoustic sources (<NUM>) capable of producing acoustic waves (<NUM>), wherein the acoustic waves produced by each of the plurality of acoustic sources interact to create a standing wave pattern forming a three dimensional shape in the plasma; and
a second energy source capable of applying non-ionizing electromagnetic radiation to the plasma, wherein the non-ionizing electromagnetic radiation is guided by the three dimensional shape.