Direct additive synthesis of diamond semiconductor

In an embodiment, a system includes a three-dimensional (3D) printer, a neutral feedstock, a p-doped feedstock, an n-doped feedstock, and a laser. The 3D printer includes a platen and an enclosure. The platen includes an inert metal. The enclosure includes an inert atmosphere. The neutral feedstock is configured to be deposited onto the platen. The neutral feedstock includes a halogenated solution and a nanoparticle having a negative electron affinity. The p-doped feedstock is configured to be deposited onto the platen. The p-doped feedstock includes a boronated compound introduced to the neutral feedstock. The n-doped feedstock is configured to be deposited onto the platen. The n-doped feedstock includes a phosphorous compound introduced to the neutral feedstock. The laser is configured to induce the nanoparticle to emit solvated electrons into the halogenated solution to form, by reduction, layers of a ceramic comprising a neutral layer, a p-doped layer, and an n-doped layer.

TECHNICAL FIELD

The present disclosure relates generally to three-dimensional (3D) printing, and in particular to 3D printing of a ceramic semiconductor.

BACKGROUND

Three-dimensional (3D) printing is an additive manufacturing process that allows for the manufacture of objects by “building up” an object. In contrast to subtractive techniques, such as machining, in which material is removed from a bulk material in order to form the shape of an object, 3D printing lays down successive layers of material to form the shape of an object. Typical materials used for 3D printing may include plastics, ceramics, and metals.

SUMMARY

According to some embodiments, a system includes a three-dimensional (3D) printer, a neutral feedstock, a p-doped feedstock, an n-doped feedstock, and a laser. The three-dimensional (3D) printer includes a platen and an enclosure. The platen includes an inert metal. The enclosure includes an inert atmosphere. The neutral feedstock is configured to be deposited onto the platen. The neutral feedstock includes a halogenated solution and a nanoparticle having a negative electron affinity. The p-doped feedstock is configured to be deposited onto the platen. The p-doped feedstock includes a boronated compound introduced to the neutral feedstock. The n-doped feedstock is configured to be deposited onto the platen. The n-doped feedstock includes a phosphorous compound introduced to the neutral feedstock. The laser is configured to induce the nanoparticle to emit solvated electrons into the halogenated solution to form, by reduction, layers of a ceramic comprising a neutral layer, a p-doped layer, and an n-doped layer.

In other embodiments, a method for additive manufacture includes introducing a boronated compound to a second neutral feedstock to form a p-doped feedstock, wherein the neutral feedstock includes a halogenated solution and a nanoparticle having a negative electron affinity. The method further includes introducing a phosphorous compound to a third neutral feedstock to form an n-doped feedstock. The method also includes depositing a first layer of a third neutral feedstock onto a platen of a three-dimensional (3D) printer. The method further includes inducing the nanoparticle of the third neutral feedstock to emit solvated electrons into the halogenated solution using a laser to form, by reduction, a first layer of a neutral ceramic. The method also includes depositing a second layer of the p-doped feedstock onto the platen of the three-dimensional (3D) printer. The method further includes inducing the nanoparticle of the p-doped feedstock to emit solvated electrons into the halogenated solution using a laser to form, by reduction, a second layer of a p-doped ceramic. The method also includes depositing a third layer of the n-doped feedstock onto the platen of the three-dimensional (3D) printer. The method further includes inducing the nanoparticle of the n-doped feedstock to emit solvated electrons into the halogenated solution using a laser to form, by reduction, a third layer of n-doped ceramic.

In yet other embodiments, a three-dimensional (3D) printer includes an inert atmosphere, a platen, and a control unit. The inert atmosphere is enclosed within the three-dimensional (3D) printer. The platen includes an inert metal. The platen is configured to have a feedstock deposited onto it. The control unit is configured to deposit a first layer of a neutral feedstock onto the platen of the three-dimensional (3D) printer. The neutral feedstock includes a halogenated solution and a nanoparticle having a negative electron affinity. The control unit is further configured to induce the nanoparticle of the neutral feedstock to emit solvated electrons into the halogenated solution using a laser to form, by reduction, a first layer of a neutral ceramic. The control unit is also configured to deposit a second layer of a p-type feedstock onto the platen of the three-dimensional (3D) printer. The p-type feedstock includes a boronated compound introduced into the neutral feedstock. The control unit is further configured to induce the nanoparticle of the p-type feedstock to emit solvated electrons into the halogenated solution using the laser to form, by reduction, a second layer of a p-doped ceramic. The control unit is also configured to deposit a third layer of an n-type feedstock onto the platen of the three-dimensional (3D) printer. The n-type feedstock includes a phosphorous compound introduced into the neural feedstock. The control unit is further configured to induce the nanoparticle of the n-type feedstock to emit solvated electrons into the halogenated solution using the laser to form, by reduction, a third layer of an n-doped ceramic.

Technical advantages of certain embodiments may include using alternating layers of neutral, p-doped, and n-doped feedstocks of negative electron affinity nanoparticle with halogenated solution to form a ceramic semiconductor without a greenware intermediary that requires heating with a kiln to form a final ceramic. Some embodiments may include forming a diamond semiconductor. Other embodiments may include forming a silicon carbide ceramic semiconductor. Other technical advantages will be readily apparent to one skilled in the art from the following figures, descriptions, and claims. Moreover, while specific advantages may have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages.

DETAILED DESCRIPTION

Embodiments of the present disclosure and its advantages are best understood by referring toFIGS. 1 through 4, like numerals being used for like and corresponding parts of the various drawings.

Current techniques of 3D printing ceramics require use of a preceramic polymer or ceramic particles plus binder to create a greenware intermediary. The greenware intermediary requires heating, often through use of a kiln, to thermolyze or sinter into a final ceramic. Heating the greenware intermediary in the kiln causes shrinkage, which must be anticipated during the design of the product.

In order to eliminate the greenware intermediary that requires heating in the kiln, embodiments of the present disclosure include 3D printing a ceramic by inducing a negative electron affinity nanoparticle in a halogenated solution to emit electrons, where the reduced halogenated compound nucleates directly form the ceramic. By 3D printing a ceramic with a negative electron affinity nanoparticle and a halogenated solution, the ceramic may be formed without the greenware intermediary that requires baking in a kiln. The 3D printing with a negative electron affinity nanoparticle and halogenated solution also avoids contaminant in the form of a catalyst or binder, because the nanoparticle is incorporated directly into the ceramic product. Embodiments of the present disclosure may also include forming a 3D ceramic of arbitrary shape at room temperature or lower.

Diamond is a form of the element carbon that has many unique properties. Diamond is among the hardest known materials, has a high melting and boiling point, and is an excellent thermal conductor as well as electrical insulator. Objects made out of diamond may be able to take advantage of these properties. For example, tools made out of diamond, such as drill bits, saws, or knives, may be more durable than tools made of conventional materials due to the hardness of diamond. Diamond can be produced in a variety of ways including as a powder in the form of diamond nanoparticles and from the pyrolysis of a pre-ceramic polymer.

The teachings of this disclosure recognize that using three-dimensional (3D) printing techniques with a negative electron affinity nanoparticle and a halogenated solution may allow for the creation of objects made of a variety of ceramics in a variety of useful shapes. In particular, using 3D printing techniques with a negative electron affinity nanoparticle (for example, a hydrogen-terminated nanodiamond) and a halogenated solution (for example, carbon tetrachloride) may allow for the creation of diamond objects in a variety of shapes. For example, using 3D printing with a negative electron affinity nanoparticle (for example, a nanodiamond) and a halogenated solution (for example, carbon tetrachloride) may allow for the creation of a diamond drill bit having almost any geometry. As other examples, 3D printing with a negative electron affinity nanoparticle (for example, nanodiamond) and a halogenated solution (for example, carbon tetrachloride) may be used to print brake pad inserts, avionics boxes, lightweight armor, diamond dialysis filters, vacuum micro-electronics, or any other appropriate object.

Further, by using different negative electron affinity nanoparticles and halogenated solutions separately or in addition to nanodiamond or carbon tetrachloride, the properties of a printed object could be varied to meet various design objectives. For example, in addition to forming diamond objects, embodiments of the present disclosure may form objects made of other carbides, such as silicon carbide, titanium carbide, hafnium carbide, vanadium carbide, or tungsten carbide.

The teachings of this disclosure recognize that alternating layers of neutral, p-type, and n-type feedstock of negative electron affinity nanoparticle and halogenated solution may be used to 3D print a ceramic semiconductor, without the need to form a greenware intermediary that requires heating in a kiln. For example, ceramic semiconductors that may be 3D printed according to the present disclosure include semiconducting diamond and/or semiconducting silicon carbide.

Further, the teachings of this disclosure recognize that a negative electron affinity nanoparticle and halogenated solution may be used to 3D print a final ceramic, without the need to form a greenware intermediary that requires heating with a kiln. In addition, the teachings of this disclosure recognize that use of a negative electron affinity nanoparticle may act as a pseudocatalyst that is incorporated into the final ceramic, without the need for using a catalyst or binder that would need to be recovered or extracted after the 3D printing is complete. The following describes methods and systems of 3D printing using a negative electron affinity nanoparticle with a halogenated solution.

The system will be described in more detail usingFIGS. 1 through 4.FIG. 1will describe an example of a 3D printer system100, according to certain embodiments.FIG. 2Awill describe the chemical structure of an example negative electron affinity nanoparticle, adamantane diamondoid200, according to certain embodiments.FIG. 2Bwill describe the chemical structure of an example halogenated solution, carbon tetrachloride205, according to certain embodiments.FIG. 2Cwill describe an example boronated compound, boron trichloride, according to certain embodiments.FIG. 2Dwill describe an example phosphorous compound, phosphorous trichloride, according to certain embodiments.FIG. 3will describe a method of additive manufacture, using a negative electron affinity nanoparticle with a halogenated solution, according to certain embodiments.FIG. 4will describe an example computer system that may be used to control the 3D printer ofFIG. 1, according to certain embodiments.

Laser120is configured to raster scan feedstock180deposited on platen130to induce solvated electrons from the negative electron affinity nanoparticle, such as adamantane diamondoid200. Laser120may emit wavelengths in the UV range. Laser120may also emit wavelengths in the visible light range. Laser120may induce a negative electron affinity nanoparticle in feedstock180to emit electrons into the halogenated solution, such as carbon tetrachloride205. The electrons may reduce the halogen solution of feedstock180to form a diatomic halogen gas or liquid and an atom, such as a carbon atom. The carbon atom may nucleate into a ceramic, such as a diamond. Laser120may be set to certain wavelength or wavelength range. For example, laser120may be set to a wavelength between 213 to 223 nm. As another example, laser120may be set to a wavelength of 532 nm. The wavelength or wavelength range may be the wavelength necessary to stimulate the emission of electrons from the negative electron affinity nanoparticle.

In some embodiments, 3D printer system100may include a control unit160. Control unit160may include a computer system that controls the printing of an object by providing instructions to 3D printer110. Control unit160may be either external to 3D printer110or incorporated into 3D printer110. Certain embodiments of control unit160are discussed in more detail below with respect toFIG. 5.

In some embodiments, 3D printer system100may include a flushing mechanism190configured to flush inert atmosphere150in enclosure140and to recover byproduct released into enclosure140. For example, in some embodiments a halogen gas byproduct may be released into enclosure140. Flushing mechanism190may flush the halogen gas byproduct from inert atmosphere150of enclosure140and securely store the halogen gas byproduct. In this way, flushing mechanism190may ensure the halogen gas byproduct does not contaminate inert atmosphere150. In this way, flushing mechanism190may also ensure the halogen gas byproduct is not released from 3D printing system100into the outside atmosphere.

Flushing mechanism190may use any conventional method of flushing necessary to remove halogen gas from enclosure140in a way that prevents release of halogen gas into the outside atmosphere. For example, flushing mechanism190may involve a continuous flow of argon gas through enclosure140and then through any conventional mechanism for recovering of halogen gas, such as by use of filters or compressors.

In some embodiments, 3D printer system100may include a draining mechanism170configured to drain feedstock180. For example, when 3D printing of an object is complete, there may be leftover feedstock180on platen130. Draining mechanism170may drain the leftover feedstock180on platen130into a storage tank. Draining mechanism170may use any conventional method of draining necessary to remove feedstock180from platen130.

Feedstock180includes a halogenated solution, such as carbon tetrachloride205. The halogenated solution, for example, may include bromine or chlorine as the halogen. It may be desirable to use a halogenated solution that is liquid at room temperature or at the temperature of the additive manufacture. For example, in embodiments forming a polycrystalline diamond ceramic, carbon tetrachloride or carbon tetrabromide may be liquid at room temperature. Other considerations in selecting a halogenated solution may also include the ease with which the diatomic halogen byproduct may be recovered. In some embodiments, it may be desirable for the other atoms of the halogenated solution to correspond with the atoms making up the ceramic product. For example, a halocarbon may be desirable as the halogenated solution when forming a polycrystalline diamond ceramic.

In embodiments forming a polycrystalline diamond ceramic, any halocarbon may be used as the halogenated solution. In such embodiments, carbon tetrachloride205, as illustrated inFIG. 28may be used. As another example, in such embodiments, carbon tetrabromide may be used in the halogenated solution. In other embodiments forming boron-nitride ceramics, (dichloroamine)dichloroborane (NCl2BCl2) may be used in the halogenated solution and nanoparticle boron nitride as the negative electron affinity nanoparticle.

In yet other embodiments forming a metal carbide ceramic, a metal or semi-metal halogen may be added to carbon tetrachloride205. For example, in embodiments forming a silicon carbide ceramic, a halogenated solution containing carbon and silicon, such as trimethyltrichlorosilane (i.e., CCl6Si), may be used. In embodiments forming a silicon carbide ceramic, the halogenated solution may include carbon tetrachloride205with the addition of silicon tetrachloride (i.e., SiCl4). In embodiments forming a titanium carbide ceramic, the halogenated solution may include carbon tetrachloride205and titanium tetrachloride (i.e., TiCl4). In embodiments forming a hafnium carbide ceramic, the halogenated solution may include carbon tetrachloride and hafnium tetrachloride (i.e., HfCl4). In embodiments forming vanadium carbide, the halogenated solution may include carbon tetrachloride205and vanadium tetrachloride (i.e., VCl4). In embodiments forming a tungsten carbide ceramic, the halogenated solution may include carbon tetrachloride and tungsten hexachloride (i.e., WCl6).

In yet other embodiments, an n-doped feedstock and a p-doped feedstock may also be formed from the neutral feedstock. For example, carbon tetrachloride may be used as a neutral feedstock. A separate n-doped feedstock may be made by introducing a phosphorous compound, such as phosphorous trichloride215, into the neutral feedstock. Additionally, a separate p-doped feedstock may be made by introducing a boronated compound, such as boron trichloride210, into the neutral feedstock. In certain embodiments, a first layer of neutral feedstock and negative electron affinity nanoparticle may be introduced onto platen130of 3D printer110. Laser120may induce the first layer to emit solvated electrons and form a first layer of neutral ceramic. A second layer of p-doped feedstock and negative electron affinity nanoparticle may be introduced onto platen130of 3D printer110. Laser120may induce the second layer to emit solvated electrons and form a second layer of p-doped ceramic. A third layer of n-doped feedstock and negative electron affinity nanoparticle may be introduced onto platen130of 3D printer110. Laser120may induce the third layer to emit solvated electrons and form a third layer of n-doped ceramic. This may be repeated until any desired number of layers are formed. For example, this may be repeated until 7 or 8 total layers are formed. This may form a ceramic semiconductor without the need for an intermediary greenware ceramic that requires thermolyzing in a kiln. The ceramic semiconductor may include a semiconducting diamond or a silicon carbide semiconductor.

Feedstock180also includes a negative electron affinity nanoparticle. Any negative electron affinity nanoparticle suitable to produce solvated electrons when induced by a laser, such as laser120, may be used depending on the desired ceramic product. The negative electron affinity nanoparticle may act as a pseudocatalyst to produce electrons and nucleate into the ceramic.

In embodiments forming a polycrystalline diamond ceramic, any diamondoid or hydrogen-terminated nanodiamond may be used as the negative electron affinity nanoparticle of feedstock180. For example in such embodiments, adamantane diamondoid200as illustrated inFIG. 2Amay be used. Other examples of negative electron affinity nanoparticles that may be used in forming polycrystalline diamond ceramic include diamantane and tetramantae. The nanodiamond or diamondoid emits electrons when illuminated by a laser, such as laser120. The reduced halocarbon then nucleates on nanodiamond or diamondoid to form diamond in sp3form. In this way, polycrystalline diamond ceramic is formed without the intermediary greenware, and without the need to heat an intermediary greenware in a kiln to form a final ceramic.

In embodiments forming a silicon carbide ceramic, an example negative electron affinity nanoparticle may include hydrogen-terminated silicon carbide nanoparticle. In yet other embodiments forming a boron nitride ceramic, negative electron affinity boron-nitride nanoparticles may be used.

FIG. 2Aillustrates the chemical structure of adamantane diamondoid200(i.e., C10H16), which may be used as a negative electron affinity nanoparticle of feedstock180in certain embodiments forming a polycrystalline diamond.

FIG. 2Billustrates the chemical structure of carbon tetrachloride205(i.e., CCl4), which may be used as a halogenated solution, according to certain embodiments.

FIG. 2Cillustrates the chemical structure of boron trichloride210, which may be used as a boronated compound. The boronated compound may be introduced to the feedstock to form a p-type feedstock.

FIG. 2lillustrates the chemical structure of phosphorous trichloride215, which may be used as a phosphorous compound. The phosphorous compound may be introduced to the feedstock to form an n-type feedstock.

FIG. 2Eillustrates an example semiconductor220, according to certain embodiments. Semiconductor220is an example semiconductor formed in certain embodiments, such as a field effect transistor (PET). Semiconductor220may be formed by performing method300. Semiconductor220includes a source225, a drain230, a p-type substrate240, a gate245, and a body250. Source225includes n-doped ceramic. Drain230includes n-doped ceramic. P-type substrate240includes p-doped ceramic. Gate245may be made of any conductive material suitable for carrying current. An insulator, such as a neutral diamond film, may separate gate245from p-type substrate240. Body250is a base or substrate containing source225and drain230. When current is applied to gate245, electrons or current may flow from source225to drain230.

FIG. 3illustrates a method300for additive manufacture using a negative electron affinity nanoparticle and a halogenated solution. Method300may be implemented by 3D printer110. Method300begins at step305where a boronated compound, such as boron trichloride210, is introduced to a second neutral feedstock to form a p-doped feedstock.

At step310, a phosphorous compound, such as phosphorous trichloride215, is introduced to a third neutral feedstock to form an n-doped feedstock.

At step315, a first layer of a first neutral feedstock is deposited onto platen130of 3D printer110.

The first, second, and third neutral feedstock comprise a halogenated solution and a nanoparticle having a negative electron affinity.

At step320, laser, such as laser120, induces the nanoparticle of the first neutral feedstock to emit solvated electrons into the halogenated solution to form a first layer of a neutral ceramic. The laser inducing the nanoparticle to emit solvated electrons into the halogenated solution may also form a diatomic halogen.

At step325, a second layer of the p-doped feedstock is deposited onto platen130of 3D printer110.

At step330, laser, such as laser120, induces the nanoparticle of the p-doped feedstock to emit solvated electrons into the halogenated solution to form a second layer of a p-doped ceramic. The laser inducing the nanoparticle to emit solvated electrons into the halogenated solution may also form a diatomic halogen.

At step335, a third layer of the n-doped feedstock is deposited onto platen130of 3D printer110.

At step340, laser, such as laser120, induces the nanoparticle of the n-doped feedstock to emit solvated electrons into the halogenated solution to form a third layer of an n-doped ceramic. The laser inducing the nanoparticle to emit solvated electrons into the halogenated solution may also form a diatomic halogen.

When all layers have been formed, method300no longer proceeds back to step305. For example, method300may no longer proceed back to step305after seven or eight layers have been formed. In some embodiments, excess feedstock180may be drained from the platen, such as platen130, and into a storage tank or into a disposal tank.

In embodiments of method300, the first layer of the neutral ceramic, the second layer of the p-doped ceramic, and the third layer of the n-doped ceramic form a ceramic semiconductor. Examples of the ceramic semiconductors that may be formed by method300include a silicon carbide semiconductor or a polycrystalline diamond semiconductor. In other embodiments of method300, a ceramic semiconductor is formed without a kiln.

After printing, the object may be subjected to additional processing steps to prepare the object for use. Examples of post-printing processing may include: painting the object, polishing the object, treating the surface of the object to render it chemically inert or to make it chemically active, and assembly of another object or device from multiple printed objects.

Modifications, additions, or omissions may be made to method300depicted inFIG. 3. Method300may include more, fewer, or other steps. For example, steps may be performed in parallel or in any suitable order. While discussed as various components of system100performing the steps, any suitable component or combination of components of system100may perform one or more steps of the method.

FIG. 4illustrates an example computer system400that may be used by the system ofFIG. 1, according to certain embodiments. One or more computer systems400perform one or more steps of one or more methods described or illustrated herein. In particular embodiments, one or more computer systems400provide functionality described or illustrated herein. In particular embodiments, software running on one or more computer systems400performs 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 systems400. 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.

In particular embodiments, computer system400includes a processor402, memory404, storage406, an input/output (I/O) interface408, a communication interface410, and a bus412. Although this disclosure describes and illustrates a particular computer system having a particular number of particular components in a particular arrangement, this disclosure contemplates any suitable computer system having any suitable number of any suitable components in any suitable arrangement.

In particular embodiments, processor402includes hardware for executing instructions, such as those making up a computer program. As an example and not by way of limitation, to execute instructions, processor402may retrieve (or fetch) the instructions from an internal register, an internal cache, memory404, or storage406; decode and execute them; and then write one or more results to an internal register, an internal cache, memory404, or storage406. In particular embodiments, processor402may include one or more internal caches for data, instructions, or addresses. This disclosure contemplates processor402including any suitable number of any suitable internal caches, where appropriate. As an example and not by way of limitation, processor402may 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 memory404or storage406, and the instruction caches may speed up retrieval of those instructions by processor402. Data in the data caches may be copies of data in memory404or storage406for instructions executing at processor402to operate on; the results of previous instructions executed at processor402for access by subsequent instructions executing at processor402or for writing to memory404or storage406; or other suitable data. The data caches may speed up read or write operations by processor402. The TLBs may speed up virtual-address translation for processor402. In particular embodiments, processor402may include one or more internal registers for data, instructions, or addresses. This disclosure contemplates processor402including any suitable number of any suitable internal registers, where appropriate. Where appropriate, processor402may include one or more arithmetic logic units (ALUs); be a multi-core processor; or include one or more processors402. Although this disclosure describes and illustrates a particular processor, this disclosure contemplates any suitable processor.

In particular embodiments, memory404includes main memory for storing instructions for processor402to execute or data for processor402to operate on. As an example and not by way of limitation, computer system400may load instructions from storage406or another source (such as, for example, another computer system400) to memory404. Processor402may then load the instructions from memory404to an internal register or internal cache. To execute the instructions, processor402may retrieve the instructions from the internal register or internal cache and decode them. During or after execution of the instructions, processor402may write one or more results (which may be intermediate or final results) to the internal register or internal cache. Processor402may then write one or more of those results to memory404. In particular embodiments, processor402executes only instructions in one or more internal registers or internal caches or in memory404(as opposed to storage406or elsewhere) and operates only on data in one or more internal registers or internal caches or in memory404(as opposed to storage406or elsewhere). One or more memory buses (which may each include an address bus and a data bus) may couple processor402to memory404. Bus412may include one or more memory buses, as described below. In particular embodiments, one or more memory management units (MMUs) reside between processor402and memory404and facilitate accesses to memory404requested by processor402. In particular embodiments, memory404includes random access memory (RAM). This RAM may be volatile memory, where appropriate Where appropriate, this RAM may be dynamic PAM (DRAM) or static PAM (SRAM). Moreover, where appropriate, this PAM may be single-ported or multi-ported RAM. This disclosure contemplates any suitable PAM. Memory404may include one or more memories404, where appropriate. Although this disclosure describes and illustrates particular memory, this disclosure contemplates any suitable memory.

In particular embodiments, storage406includes mass storage for data or instructions. As an example and not by way of limitation, storage406may include a hard disk drive (HDD), a floppy disk drive, flash memory, an optical disc, a magneto-optical disc, magnetic tape, or a Universal Serial Bus (USB) drive or a combination of two or more of these. Storage406may include removable or non-removable (or fixed) media, where appropriate. Storage406may be internal or external to computer system400, where appropriate. In particular embodiments, storage406is non-volatile, solid-state memory. In particular embodiments, storage406includes read-only memory (ROM). Where appropriate, this ROM may be mask-programmed ROM, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), electrically alterable ROM (EAROM), or flash memory or a combination of two or more of these. This disclosure contemplates mass storage406taking any suitable physical form. Storage406may include one or more storage control units facilitating communication between processor402and storage406, where appropriate. Where appropriate, storage406may include one or more storages406. Although this disclosure describes and illustrates particular storage, this disclosure contemplates any suitable storage.

In particular embodiments, I/O interface408includes hardware, software, or both, providing one or more interfaces for communication between computer system400and one or more I/O devices. Computer system400may include one or more of these I/O devices, where appropriate. One or more of these I/O devices may enable communication between a person and computer system400. As an example and not by way of limitation, an I/O device may include a keyboard, keypad, microphone, monitor, mouse, printer, scanner, speaker, still camera, stylus, tablet, touch screen, trackball, video camera, another suitable I/O device or a combination of two or more of these. An I/O device may include one or more sensors. This disclosure contemplates any suitable I/O devices and any suitable I/O interfaces408for them. Where appropriate, I/O interface408may include one or more device or software drivers enabling processor402to drive one or more of these I/O devices. I/O interface408may include one or more I/O interfaces408, where appropriate. Although this disclosure describes and illustrates a particular I/O interface, this disclosure contemplates any suitable I/O interface.

The components of computer system400may be integrated or separated. In some embodiments, components of computer system400may each be housed within a single chassis. The operations of computer system400may be performed by more, fewer, or other components. Additionally, operations of computer system400may be performed using any suitable logic that may comprise software, hardware, other logic, or any suitable combination of the preceding.