Vapor jet printing

Embodiments of the disclosed subject matter provide systems and methods of depositing a film on a selective area of a substrate. A first jet of a first material may be ejected from a first nozzle assembly of a jet head having a plurality of nozzle assemblies to form a first portion of a film deposition on the substrate. A second jet of a second material may be ejected from a second nozzle assembly of the plurality of nozzle assemblies, the second nozzle assembly being aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate, and the second material being different than the first material. The second material may react with the first portion of the film deposition to form a composite film deposition on the substrate when using reactive gas precursors.

FIELD

The present invention relates to compounds for use as emitters, and devices, such as organic light emitting diodes, including the same.

BACKGROUND

SUMMARY

According to an embodiment, an organic light emitting diode/device (OLED) is also provided. The OLED can include an anode, a cathode, and an organic layer, disposed between the anode and the cathode. According to an embodiment, the organic light emitting device is incorporated into one or more device selected from a consumer product, an electronic component module, and/or a lighting panel.

According to an embodiment, a method of depositing a film on a selective area of a substrate may be provided. A first jet of a first material may be ejected from a first nozzle assembly of a jet head comprising a plurality of nozzle assemblies to form a first portion of a film deposition on the substrate. A second jet of a second material may be ejected from a second nozzle assembly of the plurality of nozzle assemblies, the second nozzle assembly being aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate, and the second material being different than the first material. The second material may react with the first portion of the film deposition to form a composite film deposition on the substrate when using reactive gas precursors.

Each nozzle of the plurality of nozzle assemblies may include jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures may be perpendicular to the substrate, and a confinement flow ejected from the confinement apertures may be parallel to the substrate. A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate.

The selective area of the substrate upon which the composite film deposition is formed may be less than 50% of the surface area of the substrate, and may be less than 10% of the surface area of the substrate. A size of the jet head may be less than 10% of a surface area of the substrate. At least one of a length and width dimension of the jet head may be less than 25% of at least one of a length and width dimension of the substrate. The distance between the substrate and the jet head may be 10-100 μm, but may extend up to 1 mm for low resolution printing applications.

The composite film deposition may include at least one of an inorganic film, a metal film, and an organic film. The composite film deposition may be formed by using at least one of an atomic layer deposition (ALD), an atomic layer epitaxy (ALE), a chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), and remote plasma enhanced chemical vapor deposition (RPECVD). The composite film deposition may form a multi-layer barrier film over at least a portion of an organic light emitting device (OLED). The composite film deposition may include at least one of Group III-V materials. The Group III-V materials may be deposited using a showerhead having separate gas pathways for the Group III materials and the Group V materials. The composite film deposition may be formed from at least one of GaAs, AlAs, InGaAs, InP, InGaAlP, GaN, AlGaN, GaInN, and AlN. The composite film deposition may be a three-dimensional structure of at least one material selected from an organic material, an inorganic material, a metallic material, and a dielectric material. The composite film deposition may be a spatially-localized thin film transistor, a light emitting device, or an organic light emitting device.

The method may include detecting, with a sensor, one or more surface features of a device, where the composite film deposition is formed on the one or more detected surface features of the device. One of the detected surface features may be a surface defect.

An embodiment of the disclosed subject matter may provide a device to deposit a film on a selective area of a substrate. The device may include a jet head having a plurality of nozzle assemblies. The plurality of nozzle assemblies may include a first nozzle assembly to eject a first jet of a first material to form a first portion of a film deposition on the substrate, and a second nozzle assembly to eject a second jet of a second material, the second nozzle assembly being aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate, and the second material being different than the first material. The second material may react with the first portion of the film deposition to form a composite film deposition on the substrate when using reactive gas precursors.

Each nozzle of the plurality of nozzle assemblies may include of jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures is perpendicular to the substrate, and a confinement flow ejected from the confinement apertures is parallel to the substrate. A deposition channel in each of the plurality of print head assemblies may be in fluid communication with the jetting apertures. Exhaust channels, in fluid communication with the exhaust apertures, may be disposed adjacent to each deposition channel. Confinement channels, in fluid communication with the confinement apertures, may be disposed between the exhaust channels.

A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate. The nozzle assemblies that eject the first material and the second material may be surrounded by a perimeter of inert convectors that do not emit reactive gasses.

According to an embodiment, a method of depositing films on a selective area of a substrate may rely on different source gases that react at or close to a deposition site may be provided. A first jet of a first material may be ejected from a first nozzle assembly of a jet head that is separate from a second nozzle assembly of the jet head. On a surface of the substrate, a first layer deposition may be formed using the first material. The substrate or the jet head may be moved a distance corresponding to a spacing between the first nozzle assembly and the second nozzle assembly. A second jet of a second material may be ejected from the second nozzle assembly of the jet head. The second nozzle assembly may be aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate. The second material may react with the first portion of the film deposition to form a composite film deposition on the substrate when using reactive gas precursors.

The first nozzle assembly and the second nozzle assembly may be confined from one another. Each nozzle of a plurality of nozzle assemblies of the jet head may include jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures may be perpendicular to the substrate, and a confinement flow ejected from the confinement apertures may be parallel to the substrate. A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate.

The substrate or the jet head may be moved the distance corresponding to the spacing between the first nozzle assembly and the second nozzle assembly. The composite film deposition may be added to using the first material that is emitted from the first nozzle assembly.

The first nozzle assembly and the second nozzle assembly may form a nozzle assembly pair, where a number of nozzle assembly pairs of the plurality of nozzle assemblies may be equal to a film thickness divided by a bi-layer atom thickness.

The selective area of the substrate upon which the composite film deposition is formed may be less than 50% of the surface area of the substrate, and may be less than 10% of the surface area of the substrate. A size of the jet head may be less than 10% of a surface area of the substrate. At least one of a length and width dimension of the jet head may be less than 25% of at least one of a length and width dimension of the substrate. The distance between the substrate and the jet head may be 10-100 μm, but may extend up to 1 mm for low resolution printing applications.

The composite film deposition may include at least one of an inorganic film, a metal film, and an organic film. The composite film deposition may be formed using at least one of an atomic layer deposition (ALD), an atomic layer epitaxy (ALE), a chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), and remote plasma enhanced chemical vapor deposition (RPECVD). The composite film deposition forms a multi-layer barrier film over at least a portion of an organic light emitting device (OLED). The composite film deposition may be a spatially-localized thin film transistor, a light emitting device, or an organic light emitting device.

The method may include detecting, with a sensor, one or more surface features of a device, where the composite film deposition is formed on the one or more detected surface features of the device. One of the detected surface features may be a surface defect.

According to an embodiment, a system may be provided to deposit a film on a selective area of a substrate. A jet head having a plurality of nozzle assemblies may include a first nozzle assembly to eject a first jet of a first material to form, on a surface of the substrate, a first layer deposition using the first material, and a second nozzle assembly to eject a second jet of a second material when the substrate or the jet head is moved a distance corresponding to a spacing between the first nozzle assembly and the second nozzle assembly. The second nozzle assembly may be aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate. The second material may react with the first portion of the film deposition to form a composite film deposition on the substrate when using reactive gas precursors.

The first nozzle assembly of a jet head may be separate from a second nozzle assembly of the jet head, where the first nozzle assembly and the second nozzle assembly are confined from one another, and where each nozzle of a plurality of nozzle assemblies of the jet head is comprised of jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures is perpendicular to the substrate, and a confinement flow ejected from the confinement apertures is parallel to the substrate. A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate. The first nozzle assembly and the second nozzle assembly may form a nozzle assembly pair, wherein a number of nozzle assembly pairs of the plurality of alternating nozzles is equal to a film thickness divided by a bi-layer atom thickness.

According to an embodiment, a method of depositing a film on a selective area of an object may be provided. The method may include switching between a source for a first gas and a second gas. The first gas may be ejected from a first nozzle assembly of a jet head having a plurality of nozzle assemblies, and the second gas may be ejected from a second nozzle assembly of the jet head, where the second nozzle assembly is aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the object. The method may include forming, on a surface of the object, a composite film deposition by alternating the exposure of the surface of the object to the first gas and the second gas by the switching, where the composite film deposition is formed using reactive gas precursors.

Each nozzle of the plurality of nozzle assemblies is comprised of jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures is perpendicular to the object, and a confinement flow ejected from the confinement apertures is parallel to the object.

A shape and a thickness profile of the composite film deposition, and the selective area of the object upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the object. The object may be a substrate or a device.

The selective area of the object upon which the composite film deposition is formed may be less than 50% of the surface area of the object, and may be less than 10% of the surface area of the object. A size of the jet head may be less than 10% of a surface area of the object. At least one of a length and width dimension of the jet head may be less than 25% of at least one of a length and width dimension of the object. The distance between the object and the jet head may be 10-100 μm, but may extend up to 1 mm for low resolution printing applications. The formed composite film deposition may include at least one of an inorganic film, a metal film, and an organic film.

The composite film deposition may be formed using at least one of an atomic layer deposition (ALD), an atomic layer epitaxy (ALE), a chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), and remote plasma enhanced chemical vapor deposition (RPECVD). The composite film deposition may form a multi-layer barrier film over at least a portion of the device that is an organic light emitting device (OLED).

According to an embodiment, a system to depositing a film on a selective area of an object may be provided. The system may include a first source for a first gas, a second source for a second gas, and a switch to select between the first source and the second source. The first gas may be ejected from a first nozzle assembly of a jet head comprising a plurality of nozzle assemblies, and the second gas may be ejected from a second nozzle assembly of the jet head. The second nozzle assembly may be aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the object. A composite film deposition may be formed on a surface of the object by alternating the exposure of the surface of the object to the first gas and the second gas using the switch. The composite film deposition may be formed using reactive gas precursors.

Each nozzle of the plurality of nozzle assemblies may include of jetting apertures, exhaust apertures, and confinement apertures, and a jetting flow ejected from the jetting apertures is perpendicular to the object, and a confinement flow ejected from the confinement apertures is parallel to the object. A shape and a thickness profile of the composite film deposition, and the selective area of the object upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the object.

DETAILED DESCRIPTION

In some embodiments of the emissive region, the emissive region further comprises a host.

In some embodiments, the compound can be an emissive dopant. In some embodiments, the compound can produce emissions via phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence), triplet-triplet annihilation, or combinations of these processes.

The organic layer can also include a host. In some embodiments, two or more hosts are preferred. In some embodiments, the hosts used maybe a) bipolar, b) electron transporting, c) hole transporting or d) wide band gap materials that play little role in charge transport. In some embodiments, the host can include a metal complex. The host can be an inorganic compound.

Combination with Other Materials

Various materials may be used for the various emissive and non-emissive layers and arrangements disclosed herein. Examples of suitable materials are disclosed in U.S. Patent Application Publication No. 2017/0229663, which is incorporated by reference in its entirety.

A hole injecting/transporting material to be used in the present invention is not particularly limited, and any compound may be used as long as the compound is typically used as a hole injecting/transporting material.

An electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped), or doped. Doping may be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complexes or organic compounds may be used as long as they are typically used to transport electrons.

Charge Generation Layer (CGL)

Embodiments of the disclosed subject matter may provide OLED (organic light emitting device) encapsulation by alternating deposition channels in a Confined Organic Printing (COP) type device to produce aluminum oxide. This may be similar to forming an atomic deposition layer (ALD). Because of the small size of the deposition channels and the isolation between channels, a growth rate may be very rapid. This may address one of the biggest problems for ALD encapsulation, which is slow growth rate. Using the micro-CVD (chemical vapor deposition) printing aperture system discussed throughout, encapsulation may be used to form features and/or cover defects or particles on a device, a display, or the like.

Embodiments of the disclosed subject matter may provide local encapsulation. For example, ALD or multi-layer stack (that may be, for example, organic, inorganic, ALD, a combination thereof, or the like) over selective areas of a display and/or device to add specific strength to local areas. For example, the ALD and/or multi-layer stack may be added along the fold region of a foldable OLED display. Micro-ALD or micro-ALE (atomic layer epitaxy) may provide close spacing of deposition channels to provide a high growth rate.

High aluminum content Group III-nitride materials may be difficult to grow rapidly due to gas phase interaction between trimethyl aluminum and ammonia. In embodiments of the disclosed subject matter, using a depositor-exhaust-confinement type (DEC-type) showerhead, extremely high growth rates may be achieved, which may be beneficial for forming deep ultraviolet light emitting devices (e.g., for purification purposes).

Embodiments of the disclosed subject matter may provide selective area deposition by micro CVD. A DEC-type print aperture may be used to print materials in the same manner as ink jet, but using CVD materials and technique (e.g., by using cold gas and a hot substrate). This could be used, for example to “print” optical elements on silicon devices. Although some initiatives have attempted to do this with bulk films, small structures may be easier to grow using lattice mis-matched materials.

Implementations of the disclosed subject matter may be used to form organic TFTs (thin film transistors) for display backplanes, where it may be desirable to cover a small portion of the pixel area. Embodiments of the disclosed subject matter may also use Plasma Enhanced Chemical Vapor Deposition (PECVD), or micro PECVD.

Embodiments of the disclosed subject matter may provide additive deposition of thin films of different materials to form and/or build up three-dimensional (3D) stacks. Locally deposited thin films may be used to repair holes and/or other defects in existing films.

Some prior systems, such as described in U.S. Patent Publn. No. 2016/0068953, require separate pressure gages and controllers for each exhaust channel. In contrast, embodiments of the disclosed subject matter provide configurations with small dimensions that are controlled by flow restriction in the exhaust channels.

In some embodiments, a similar concept to those described above may be used for Group III-V epitaxy, where TMA (trimethyl aluminum) may react with ammonia in the gas phase. The highest quality material and fastest growth rates may be achieved when TMA and NH3do not mix in the gas phase.

Group III-V materials may be separated in the delivery system that may include a “showerhead.” Typically, the Group III and Group V materials may mix in the gas space between the showerhead and substrate. For AlN, the TMA and NH3may react in the gas phase to form adducts, which may reduce the growth rate (as it consumes TMA) and creates particles. Injecting TMA and NH3in separate regions minimizes the issue of reduction in growth rate. Using DEC, such a reduction in growth rate may be eliminated.

There may be applications where it is desirable to accurately deposit or print thin films on a specific location on a substrate. Vapor jet printing may lower printing costs by applying materials in a particular location, as opposed to coating a complete substrate. The use of a small monolithic printing head assembly may reduce heating from a hot printing head to a substrate, which can avoid damage to devices already deposited on to the substrate. This is because in VJP or spatial ALD (atomic layer deposition), source-to-substrate distances may be less than 1 mm, so if a large print head is heated to high temperatures (e.g., 300° C.) and placed less than 1 mm from a substrate for a plurality of seconds, the substrate surface may heat.

The use of DEC print heads may enable the deposition of films that use different source gases that react at, or close to, a deposition site. For example, in ALD, a first gas may be placed on a substrate for a monolayer deposition. When the first gas is removed and a second gas is applied to the same location, a monolayer growth may occur when the second gas reacts with the surface layer deposited from the first gas. These operations may be repeated to build up monolayers of film. Spatial ALD may benefit from DEC VJP technology to avoid mixing of gases prior to the gasses meeting at the growth site. Use of a monolithic print head may provide pinpoint and/or line deposition over one or more selective areas of a substrate to avoiding wasting material.

The two gases may be introduced to the growing surface by several approaches. Firstly, multiple heads may be used, each jetting a different gas and aligned such that a nozzle from one jet head emitting gas A is aligned with a nozzle from a second jet head emitting gas B. The growing surface may experience a series of ABAB gas exposures to grow an ALD film. A second approach may have one jet head with alternating ABABAB nozzles confined from each other. The substrate or print head may be moved a distance corresponding to the nozzle spacing, so the second source gas may reach the growing surface. The assembly may then may be moved back to have the first source gas jetted on to the growing surface. In some embodiments, a plurality of alternating nozzles may be stacked to yield a desired film thickness on one printing pass. The number of pairs of nozzles may be equal to a film thickness divided by the bi-layer atom thickness. A third approach could be to have the gases coming out of the nozzle switched at the source to create an ABAB growth pattern on the substrate surface. The advantages of using monolithic assembly VJP for spatial ALD is that the small volumes inherent in VJP may provide fast purging times and deposition rates, unlike conventional ALD where the purging times to remove one gas before another is introduced lead to low deposition rates. Another advance of using monolithic assembly VJP for spatial ALD is for high utilization of material. Both of these features may reduce production costs.

Many devices, particularly organic devices such as OLEDs, solar cells, and transistors, may be sensitive to air and moisture, and thin film barrier films may be deposited on such devices to provide isolation. One such encapsulation approach may use ALD, as described above. For OLEDs, a multi-layer system having dyads or pairs of alternating films may be used, where one film is organic and one film is inorganic. In some embodiments, a single layer barrier with both organic and inorganic properties in the same film may be used. The approaches described above may be used to produce a multi-layer system with nozzle A producing a deposition, for example, of inorganic barrier film, and a second nozzle B producing an organic film. Using one of the three operations discussed above, a multi-layer film may be grown. This may rely on CVD or remote plasma PECVD processes for individual film deposition.

As ALD encapsulation may have very high quality, one approach may be to coat an OLED with a blanket thin film encapsulation, and then apply an ALD based system locally using VJP in regions where it is desirable to have a very high quality film, such as for a foldable AMOLED display, along the region which will undergo repetitive folding.

Vapor deposition of III-V materials such as GaAs, AlAs, InGaAs, InP, InGaAlP, GaN, AlGaN, GaInN, and AlN may be deposited using showerheads. The Group III materials and Group V materials may have separate gas pathways. The Group III and Group V materials mix in the gas phase between the vapor injector and heated substrate. Trimethyl aluminum is particularly reactive with the Group V precursors (e.g., arsine, phosphine, or ammonia) and may react in the gas space between the substrate and gas injector. Any adducts formed may reduce the efficiency of material utilization and may produce particulates if the adducts grow to sufficient size. In the case of AlN, the adduct formation may limit the growth rate of AlN to less than 1 μm/hour. In some deposition systems, increasing the flow of TMA may reduce the growth rate due to an increase in the rate of adduct formation. In one embodiment, the formation of adducts may be minimized by adding a purge flow between the TMA and NH3injectors to minimize gas phase mixing.

Using DEC print heads for Group III-V epitaxy may eliminate the issue of efficiency of material utilization and the production of particulates. Gas phase mixing may be eliminated by the introduction of exhaust channels adjacent to each deposition channel and adding a confinement channel between exhaust channels. The sequence of channels may be: C-E-TMA-E-C-E-NH3-E (where C=Confinement, and E=Exhaust). This sequence may be repeated a plurality of times to increase growth rate in a linear system, or may be spaced radially in the case of a showerhead-type system with a rotating susceptor.

Chemical vapor deposition (CVD) processes and plasma assisted CVD may be applied to local regions of a substrate using gases ejected from nozzles of a VJP system. Advantages of this arrangement may include high material utilization by particular coating regions of need.

CVD is a chemical process that may be used to produce high quality, high-performance, solid materials. The process may be used in the semiconductor industry to produce thin films. In typical CVD, the wafer (substrate) may be exposed to one or more volatile precursors, which react and/or decompose on the substrate surface to produce the desired deposit. Frequently, volatile by-products are also produced, which may be removed by gas flow through the reaction chamber.

CVD may be performed in a variety of process formats. These processes generally differ in how the chemical reactions may be initiated. For example, CVD may be classified by the type of substrate heating, such as hot wall CVD, in which the chamber is heated by an external power source and the substrate is heated by radiation from the heated chamber walls. With another type of substrate heating, such as cold wall CVD, the substrate may directly heated either by induction or by passing current through the substrate itself or a heater in contact with the substrate. The chamber walls may be at room temperature.

CVD may be classified by the type of plasma processing used. For example, CVD may be classified as microwave plasma-assisted CVD (MPCVD). CVD may be classified as Plasma-Enhanced CVD (PECVD), which may utilize plasma to enhance chemical reaction rates of the precursors. PECVD processing may allow for deposition at lower temperatures, which may be beneficial in the manufacture of semiconductors. The lower temperatures may allow for the deposition of organic coatings, such as plasma polymers, that have been used for nanoparticle surface functionalization. CVD may also be classified as remote plasma-enhanced CVD (RPECVD), which may be similar to PECVD except that the wafer substrate is not directly in the plasma discharge region. RPECVD may include removing the wafer from the plasma. This approach may enable micro PECVD using VJP, given the very small dimensions of the system, which may not allow a plasma to be struck between ejection nozzle and substrate.

Three-dimensional (3D) printing, which may be used to fabricate 3D structures, is based on printing a range of materials from a liquid form. VJP may be used to form complex 3D structures having a plurality of materials deposited from a vapor, as opposed to liquid form. Such materials could be organic, metallic, dielectric, or the like. Stacks of alternating materials may not be limited to similar materials, such as inorganics on top of inorganics (ALD of Al2O3). Organics may be deposited on top of inorganics, metals, or oxides to form composite multi-layer structures.

Large area devices may often have defects arising from particulates. For organic devices which are very sensitive to the environment, any pin holes in the thin film encapsulation barrier protecting them from ambient conditions may lead to black spots and degradation of the organic devices. Encapsulation films deposited by VJP may be used the seal any pin-holes when they are detected. Detection and encapsulation may be performed locally relatively quickly, without needing to coat the whole device area. If a defect or black spot is detected from a test where all pixels of a device are illuminated, the location of the defect or black spot may be noted and the device may be placed into a VJP chamber and the jet head placed over the detected defective area to re-seal it and prevent further degradation. This may increase the yield of fabricating very large area devices, where the probability of defects and/or pin holes becomes significant and the cost of rejecting a device or display is also high, making repair desirable. This approach may be used with any device having pin holes and/or defects in a thin film barrier layer.

An array of patterned thin film features comprised of compound material formed from reactive gas precursors may be deposited by VJP using a grid of isolated convective cells. Each convective cell may include one of the relevant precursors, and may be isolated from its neighbors. The compound material may be a Group III-V semiconductor or a Group II-VI material grown in a manner analogous to MOCVD or ALD, respectively. VJP may be differentiated from these techniques primarily by the capability of printing pinpoint features without the use of shadow masks or subtractive patterning. Other material sets may be possible for VJP, and any solid material that can be formed from two or more vaporized precursors may be used.

Organic Vapor Jet Printing (OVJP) may utilize a carrier gas to transport organic material from a heated source container to the print nozzle assembly which is in close proximity to a substrate. The nozzle assembly then forms the organic vapor into jets that condense onto well-defined zones of the substrate, allowing patterns to be generated in the resulting film. A micronozzle array, such as disclosed in U.S. Patent Publn. No. 2015/0376787, incorporated by reference herein, may utilize a combination of deposition apertures surrounded by exhaust apertures and a gas confinement flow to confine the line width and overspray. This arrangement may be referred to as DEC (Deposition-Exhaust-Confinement).

Overspray may be eliminated by using a flow of confinement gas to prevent the diffusion and transport of organic material away from a desired deposition region. Preferably, a chamber pressure range of 50 to 300 Torr may be used.FIGS. 3A-3Bshow an OVJP depositor, and a micronozzle array on which one or more OVJP depositors are arranged. A depositor design, shown from the perspective of the substrate inFIG. 3A, may include one or more rectangular delivery apertures301located between a pair of exhaust apertures302. The flow through the delivery apertures301may include organic vapor entrained in an inert delivery gas. The exhaust apertures302may withdraw gas from the region under the depositor at a mass flow rate exceeding the delivery flow. The exhaust apertures302may remove the delivery flow and any surplus organic vapor entrained within it, as well as a balance of confinement gas drawn from the ambient surrounding the depositor. Delivery apertures301and exhaust apertures302may be separated by a width of a DE (Deposition-Exhaust) spacer303. Delivery apertures301and exhaust apertures302may be arranged so that the long axes are parallel to the direction of printing304. A solid section called the flow retarder305may be positioned between the delivery apertures301to modulate the delivery gas flux profile impinging onto the substrate (e.g., substrate314shown inFIG. 3B).

Depositors306may be arranged linearly on a micronozzle array307, so that each depositor may border another on at least one of its side boundaries308. The top and bottom edges309of the depositor are defined by the edges of a linear micronozzle array (e.g., micronozzle array307shown inFIG. 3A). Distribution channels310placed between depositors306may provide a source of confinement gas along the sides of each of the depositors306. Alternately, confinement gas may flow in from the edges of the depositors306, particularly if these channels are omitted. Micronozzle array307may be configured to minimize crosstalk between depositors306so that multiple printed features are as close to identical as possible across the width of the depositor array (e.g., the array of depositors306of the micronozzle array307).

FIG. 3Bshows a cross-section of a depositor (e.g., one of the depositors306shown inFIG. 3A). The channels shown inFIG. 3Bmay be etched into silicon and sealed on the top and bottom by wafer bonding techniques. Delivery channels311may carry organic vapor laden delivery gas to delivery apertures301that are surrounded on each side by exhaust apertures302. The exhaust apertures302may connect to exhaust channels312that may remove excess vapor from the desired printing zone315. Confinement gas may be fed into the sides of the depositor by the distribution channels310. The confinement gas may sweep inward through the gap313created between the depositor and the substrate314. The inward sweep of confinement gas driven by negative pressure at the exhaust aperture may prevent the flow of organic vapor laden gas from the delivery aperture from migrating beyond the desired printing zone315. Organic vapor from the delivery aperture may adsorb to the substrate314within the printing zone to produce a well-defined thin film feature with no overspray beyond it.

FIG. 4shows a section of a micronozzle array having a time-stable DEC VJP depositors according to an embodiment of the disclosed subject matter. Depositors401may deposit reactant A, and depositors402may deposit reactant B. Each depositor401,402may create a convective cell over the substrate. Depositors401,402may be arranged in rows403of alternating depositor types with dispersed confinement gas sources404located between adjacent rows.

FIG. 5shows a cross-section of a time stable DEC VJP micronozzle array printing a compound material onto a substrate according to an embodiment of the disclosed subject matter. A depositor array501having print heads and substrate502are show cross section inFIG. 5parallel to the plane of the substrate502and perpendicular to the direction of motion502a. If the depositor array501is moved linearly with respect to a substrate502, discrete lines of deposition may form, corresponding to the rows on the print head. As the substrate502moves relative to the depositors, the printed zones on the substrate502may alternate between exposure to rows of convective cells503to deposit reactant A and convective cells504to deposit reactant B. This may result in the buildup of an ordered compound material505.

FIG. 6shows a frontal section of a time stable DEC VJP micronozzle array printing a compound material onto a substrate according to an embodiment of the disclosed subject matter. The print head and substrate are illustrated in cross-section transverse to the direction of substrate motion. Each column of depositors601(orthogonal to rows) may correspond to a line of compound material602. Confinement flow may be distributed between adjacent rows of depositors by porous tracks603in the print head that run parallel to the direction of substrate motion.

FIG. 7shows streamlines of flow of process gasses for a time stable DEC VJP micronozzle array according to an embodiment of the disclosed subject matter. That is, convective cells generated by the print head are shown inFIG. 7. The cells are arranged in a two-dimensional grid. In this particular configuration, rows701contain cells of vapor A and rows702contain cells of vapor B. In one configuration, depositors of varying types may be arranged in a checkerboard configuration. Confinement gas may be distributed through rows of nozzles703that run orthogonally to the rows701,702of like material depositors. A positive pressure (relative to a chamber pressure) feed of confinement gas may be used to maintain uniformity for this ALD-VJP structure, since confinement gas may be evenly distributed to depositors that may be several rows deep within an array and do not share a perimeter with the chamber ambient.

The streamlines704generated by each depositor705may not cross into neighboring depositors. This may indicate that each depositor and the convective cell within it are isolated from its neighbors. A high level of uniformity between depositors may be obtained by a repeating array, since uniformity is equivalent to two-dimensional periodic symmetry in this context.

FIG. 8shows a ring of inert convectors around a time stable DEC VJP micronozzle array according to an embodiment of the disclosed subject matter. As shown inFIG. 8, inert convectors801may surround the perimeter of a micro-nozzle array containing depositors jetting precursors802(precursor A) and precursor803(precursor B) to minimize edge effects. These inert convectors801may have exhaust and confinement flows but the delivery flow like depositors, if present, may not contain any reactive vapor.

Micro-valves can be monolithically integrated into a VJP depositor array as described in U.S. patent application Ser. No. 16/243,393 filed Jan. 9, 2019, incorporated by reference herein, in its entirety. In addition to switching flow on and off, the valves can switch the source of flow feeding the delivery aperture between two sources of dissimilar vapor.FIG. 9shows a MEMS (Micro-Electro-Mechanical Systems) valve used in a time-variable DEC VJP micronozzle array according to an embodiment of the disclosed subject matter. In particular, an example of a depositor within a valved print head is shown in a cross-section inFIG. 9. Two plug valves901,902may be separated from their surrounding channels903by etching. The plug valves901,902may be connected to the sidewalls of the channels904by flexures905. The plug valves901,902may be actuated by pushrods attached to the far ends of stems906that may be actuated by a piezoelectric array. A central channel907may feed a continuous stream of inert delivery gas that is not laden with a reactive vapor.

The left hand channel (i.e., the channel to the left of central channel907) with a micro-valve (e.g., plug valve901) may carry delivery gas with reactive species A. The right hand channel (i.e., the channel to the right of central channel907) may carry delivery gas with reactive species B. When the left hand stem906is depressed and the right hand valve (e.g., plug valve902for the channel to the right of central channel907) is not depressed, as shown inFIG. 9, vapor containing species B flows downward to the delivery aperture908. Vapor with species A flows through the delivery aperture when the valve positions are reversed (i.e., when plug valve902is closed and plug valve901is open). Both stems906may be depressed so vapor flow from both channels is blocked by the plug valves901,902. This may be done to purge the delivery plenum909so that species A and B do not react within it. A feature made from compound material may be deposited by repeatedly cycling the valves901,902(i.e., alternating the opening and closing of each valve independently) so that species A is jetted from the delivery aperture908, then the delivery aperture908is purged, then species B is jetted form the delivery aperture908, and the delivery aperture908is again purged, at which point the cycle repeats.

The depositor may include other features of the DEC depositor as discussed above. The delivery aperture may be flanked on both sides by exhaust channels910that remove unreacted vapor from the deposition zone. The confinement channels previously discussed may be replaced with “scallop” type transverse channels911that extend through the thickness of the micronozzle array and draw confinement gas from the chamber ambient. Due to the greater internal complexity of this structure, it may be more practical to arrange depositors abreast as shown inFIGS. 3A-3B, as opposed to in a two dimensional array as shown inFIG. 4. Since a single depositor can alternate material types, it may not be necessary to overfly a feature with multiple depositors. An advantage of a time-variable print head is that it may allow discontinuous features to be printed. Features printed by a time-stable print head may begin and end in the runout zone of the substrate. Otherwise, the beginning and end portions of the feature will be thinner than the central portions, since fewer depositors will pass over them. Another advantage of a time-variable print head is that the use of microvalves and close coupled exhaust may permit the switching of precursors with very small time constants. Since the growth rate is often limited by the time needed to switch between precursors for each atomic layer, this may greatly increase the overall deposition rate. Due to the very small volume of the delivery plenum, up to 3,000 complete cycles per second of A and B deposition, with intra-cycle purges, may be possible.

As shown inFIGS. 3A-9and described above, a film (e.g., compound material505,605shown inFIGS. 5-6) may be formed on a selective area of a substrate (e.g., substrate502shown inFIGS. 5-6). A first jet of a first material may be ejected from a first nozzle assembly (e.g., depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5may eject reactant A) of a jet head comprising a plurality of nozzle assemblies to form a first portion of a film deposition on the substrate. A second jet of a second material may be ejected from a second nozzle assembly (e.g., depositor402shown inFIG. 4, and/or convective cell504shown inFIG. 5may eject reactant B) of the plurality of nozzle assemblies, the second nozzle assembly being aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the substrate, and the second material being different than the first material. The second material may react with the first portion of the film deposition to form a composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) on the substrate when using reactive gas precursors.

Each nozzle of the plurality of nozzle assemblies may include jetting apertures (e.g., delivery aperture301shown inFIG. 3), exhaust apertures (e.g., exhaust apertures302shown inFIG. 3), and confinement apertures (e.g., distribution channels310shown inFIG. 3), and a jetting flow ejected from the jetting apertures may be perpendicular to the substrate, and a confinement flow ejected from the confinement apertures may be parallel to the substrate. A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate.

The selective area of the substrate upon which the composite film deposition is formed may be less than 50% of the surface area of the substrate, and may be less than 10% of the surface area of the substrate. For example, the compound material602sshown inFIG. 6may be less than 50% of the surface area of the substrate502. A size of the jet head may be less than 10% of a surface area of the substrate. For example, the size of each of the convective cells503,504shown inFIG. 5and/or the depositors601shown inFIG. 6may be less than 10% of the surface area of the substrate502. At least one of a length and width dimension of the jet head may be less than 25% of at least one of a length and width dimension of the substrate. As shown inFIGS. 5-6, the size of each of the convective cells503,504and/or the depositors601may be less than 25% of the surface area of the substrate502. The distance between the substrate and the jet head may be 10-100 μm, but may extend up to 1 mm for low resolution printing applications.

The composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) may include at least one of an inorganic film, a metal film, and an organic film. The composite film deposition may be formed by using at least one of an atomic layer deposition (ALD), an atomic layer epitaxy (ALE), a chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), and remote plasma enhanced chemical vapor deposition (RPECVD). The composite film deposition may form a multi-layer barrier film over at least a portion an organic light emitting device (OLED). The composite film deposition may include at least one of Group III-V materials. The Group III-V materials may be deposited using a showerhead having separate gas pathways for the Group III materials and the Group V materials. The composite film deposition may be formed from at least one of GaAs, AlAs, InGaAs, InP, InGaAlP, GaN, AlGaN, GaInN, and AlN. The composite film deposition may be a three-dimensional structure of at least one material selected from an organic material, an inorganic material, a metallic material, and a dielectric material. The composite film deposition may be a spatially-localized thin film transistor, a light emitting device, or an organic light emitting device.

One or more surface features may be detected, where the composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) is formed on the one or more detected surface features of the device. One of the detected surface features may be a surface defect.

In some embodiments, films (e.g., compound material505,605shown inFIGS. 5-6) may be deposited on a selective area of a substrate (e.g., substrate502shown inFIGS. 5-6) that rely on different source gases that react at or close to a deposition site (e.g., desired printing zone315shown inFIG. 3B). A first jet of a first material may be ejected from a first nozzle assembly (e.g., depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5may eject reactant A) of a jet head that is separate from a second nozzle assembly (e.g., depositor402shown inFIG. 4, and/or convective cell504shown inFIG. 5may eject reactant B) of the jet head. On a surface of the substrate (e.g., substrate502shown inFIGS. 5-6), a first layer deposition may be formed using the first material. The substrate or the jet head may be moved a distance (e.g., in direction502ashown inFIG. 5) corresponding to a spacing between the first nozzle assembly and the second nozzle assembly. A second jet of a second material may be ejected from the second nozzle assembly (e.g., depositor402shown inFIG. 4, and/or convective cell504shown inFIG. 5may eject reactant B) of the jet head. The second nozzle assembly may be aligned with the first nozzle assembly parallel to a direction of motion (e.g., direction502ashown inFIG. 5) between the plurality of nozzle assemblies and the substrate. The second material may react with the first portion of the film deposition to form a composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) on the substrate when using reactive gas precursors.

The first nozzle assembly and the second nozzle assembly may be confined from one another. Each nozzle of a plurality of nozzle assemblies of the jet head may include jetting apertures (e.g., delivery aperture301shown inFIG. 3), exhaust apertures (e.g., exhaust apertures302shown inFIG. 3), and confinement apertures (e.g., distribution channels310shown inFIG. 3), and a jetting flow ejected from the jetting apertures may be perpendicular to the substrate (e.g., substrate502shown inFIGS. 5-6), and a confinement flow ejected from the confinement apertures may be parallel to the substrate. A shape and a thickness profile of the composite film deposition, and the selective area of the substrate upon which the composite film deposition is formed, may be based on a size and shape of the first nozzle assembly and the second nozzle assembly, and a distance between the jet head and the substrate.

The substrate or the jet head may be moved the distance (e.g., in direction502ashown inFIG. 5) corresponding to the spacing between the first nozzle assembly and the second nozzle assembly (e.g., the space between depositors401and402shown inFIG. 4, or the space between convective cell503and convective cell504shown inFIG. 5). The composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) may be added to using the first material that is emitted from the first nozzle assembly (e.g., depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5).

The first nozzle assembly (e.g., depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5) and the second nozzle assembly (e.g., depositor402shown inFIG. 4, and/or convective cell503shown inFIG. 5) may form a nozzle assembly pair, where a number of nozzle assembly pairs of the plurality of nozzle assemblies may be equal to a film thickness divided by a bi-layer atom thickness.

In some embodiments, a film (e.g., compound material505,605shown inFIGS. 5-6) may be deposited on a selective area of an object (e.g., substrate502shown inFIGS. 5-6, or a device), where there is switching between a source for a first gas (e.g., reactant A that may be ejected from depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5) and a second gas (e.g., reactant B may be ejected by depositor402shown inFIG. 4, and/or convective cell504shown inFIG. 5). The first gas may be ejected from a first nozzle assembly (e.g., depositor401shown inFIG. 4, and/or convective cell503shown inFIG. 5) of a jet head having a plurality of nozzle assemblies, and the second gas may be ejected from a second nozzle assembly (e.g., depositor402shown inFIG. 4, and/or convective cell504shown inFIG. 5) of the jet head, where the second nozzle assembly is aligned with the first nozzle assembly parallel to a direction of motion between the plurality of nozzle assemblies and the object. On a surface of the object, a composite film deposition (e.g., compound material505shown inFIG. 5, and/or compound material602shown inFIG. 6) may be formed by alternating the exposure of the surface of the object to the first gas and the second gas by the switching, where the composite film deposition is formed using reactive gas precursors.