Processes and uses of photochemical and thermal release layers in device manufacturing.

Abstract

A process is described for transferring a component from a release layer by exposing the release layer to light and heat from different sources, the process includes providing an assembly including a substrate, a release layer, and a component, heating the release layer, and exposing the release layer to light at an actinic wavelength, where the heat source and the actinic radiation source are different sources.

Description

[Technical field]

[0001] Incorporation by reference of any priority application Any and all applications for which a foreign or domestic priority claim is identified in an Application Data Sheet submitted with this application, such as U.S. Provisional Patent Application No. 63 / 278,323, filed November 11, 2021, are incorporated by reference into this specification under 37 CFR 1.57 and Rules 4.18 and 20.6.

[0002] The present invention relates to release layers used to releasably transfer components from one surface to another during the manufacture of microelectronic devices. [Background technology]

[0003] The transfer of microelectronic objects from one surface to another pervades the process of assembly and packaging of functional products, whether these are purely electronic (such as in the case of computer motherboards), optoelectronic (such as in the case of displays or optical communication devices in or between electronic components), sensors, or actuators. The physical properties of the patterning system limit the size of the systems that can be made in one integrated parallel process, and the process compatibility limits the type of materials. Therefore, useful systems require integration at the packaging level.

[0004] Integrated circuits allowed various components (e.g. passive components) to be fabricated by the same technology as transistors, making it possible to create entire functional circuits by parallel processing; that is, simultaneous processing of areas rather than devices. Today, most of the innovation in microelectronics is focused on packaging, and specifically heterogeneous packaging. This means that many different kinds of integration technologies (silicon ICs-digital or analog, compound semiconductor ICs as well as light emitters and receivers, microelectromechanical sensors, and other devices and systems) are brought together in novel ways to achieve better performance.

[0005] Although many techniques are currently used for processing and packaging of microelectronics, for example, serial pick and place, laser ablation, stamping, and adhesives, further advances in the field are still needed. Summary of the Invention

[0006] For purposes of briefly describing the disclosure and the advantages achieved over the prior art, certain specific objectives and advantages of the disclosure are described herein. Not all such objectives or advantages may be achieved in any particular embodiment. Thus, for example, one skilled in the art will understand that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or advantages taught herein without necessarily achieving other objectives or advantages that may be taught or suggested herein.

[0007] All of these embodiments are intended to be within the scope of the invention disclosed herein. These and other embodiments will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments, with reference to the accompanying figures. The invention is not limited to any specific preferred embodiment(s) disclosed.

[0008] In one aspect, a process for transferring a component is described. The process includes: a substrate; Providing an assembly including a release layer and a component includes: the release layer is disposed on a substrate, and the component is adhered to the release layer; heating the release layer from a heating source to at least a decomposition temperature, the heating being selected from the group consisting of conductive heating, radiative heating, and combinations thereof; and exposing the release layer to actinic wavelengths of light from an actinic radiation source; the heating and exposing steps decompose the release layer and transfer the component from the substrate to the target substrate; the heating source and the actinic radiation source are different sources; and at least one of the heating and exposing steps is performed within a pulse period.

[0009] In some embodiments, the heating comprises radiative heating with light at an irradiating wavelength, and the overlap between the irradiating wavelength and the actinic wavelength is at most 20%. In some embodiments, the radiative heating is at an irradiating wavelength selected from the group consisting of UV wavelengths, visible light wavelengths, IR wavelengths, microwave wavelengths, and combinations thereof. In some embodiments, the radiative heating is at an irradiating wavelength between about 300 nm and about 100,000 nm. In some embodiments, the substrate comprises a donor plate and a light absorbing material. In some embodiments, the light absorbing material is selected from the group consisting of Nd2O3, Sm2O3, V2O3, CoO, NiO, MnO2, polycarbonate compounds, aromatic compounds, and combinations thereof. In some embodiments, the radiative heating is applied to a side edge of the assembly.

[0010] In some embodiments, the decomposition temperature is between about 100° C. and about 350° C. In some embodiments, the process further comprises heating the release layer to a first temperature prior to heating the release layer to the decomposition temperature. In some embodiments, the first temperature is between about 100° C. and about 350° C. In some embodiments, the pulse duration is between about 10 ns and about 10 μs. In some embodiments, the heating step is performed before the exposing step. In some embodiments, the heating step is performed after the exposing step. In some embodiments, the heating step is performed simultaneously with the exposing step.

[0011] In some embodiments, the actinic wavelength of the light is selected from the group consisting of UV wavelengths, visible wavelengths, and combinations thereof. In some embodiments, the actinic wavelength of the light is from about 200 nm to about 400 nm. In some embodiments, the actinic radiation source has an intensity of about 10 mJ / cm 2 ~about 200mJ / cm 2 Includes power density.

[0012] In some embodiments, heat is applied directly to the release layer. In some embodiments, heat is applied directly to the part, which heats the release layer to the decomposition temperature. In some embodiments, heat is applied directly to the substrate, which heats the release layer to the decomposition temperature.

[0013] In some embodiments, the assembly further comprises a conductive heat source. In some embodiments, the conductive heat source comprises a transparent conductive heat source. In some embodiments, the transparent conductive heat source is selected from the group consisting of ITO, β-Ga2O3, gold, silver, La-doped SrSnO3, and combinations thereof.

[0014] In another aspect, a process for transferring a component is described, the process comprising: providing an assembly including a substrate, a release layer, and a component, the release layer being disposed on the substrate and the component being adhered to the release layer; heating the release layer from a heat source to at least a decomposition temperature, the heating being selected from the group consisting of conductive heating, radiative heating, and combinations thereof, and the decomposition temperature being about 180° C. to about 220° C.; and exposing the release layer to light at an actinic wavelength from an actinic radiation source, the actinic radiation wavelength being about 230 nm to about 360 nm; the heating and exposing steps decompose the release layer and transfer the component from the substrate to a target substrate; and heating the heat source and the actinic radiation source to at least a decomposition temperature, the decomposition temperature being about 180° C. to about 220° C. are distinct sources; and at least one of the heating and exposing steps is performed within a pulse duration of about 10 ns to about 10 μs.

[0015] In another aspect, an assembly for transferring a component is described, the assembly including: a substrate, a plurality of heating sources disposed over the substrate, and a release layer disposed over the plurality of heating sources.

[0016] In some embodiments, the assembly further comprises a nanoporous material disposed between the substrate and the plurality of heating sources.

[0017] In another aspect, an assembly for transferring a component is described that includes: a substrate, a light absorbing layer disposed over the substrate, a first cladding layer disposed over the light absorbing layer, and a release layer disposed over the first cladding layer.

[0018] In some embodiments, the assembly further comprises a second cladding layer disposed between the substrate and the light absorbing layer, hi some embodiments, the light absorbing layer is a graded light absorbing layer. [Brief description of the drawings]

[0019] [Figure 1]FIG. 1 illustrates an embodiment of a process flow for transferring a part (C) from an optically transparent donor plate (A) to a target substrate (D) using a release layer composition (B). [Diagram 2] FIG. 2 is a flow chart of an embodiment of a process for decomposing the release layer by heating the assembly and / or exposing it to light. [Diagram 3] FIG. 3 is a flow chart of an embodiment of the process in which multiple heating steps are performed in a process for heating the assembly and / or exposing it to light to decompose the release layer. [Figure 4A] FIG. 4A shows a top view of an embodiment of a donor plate assembly including multiple heating sources. [Figure 4B] FIG. 4B shows a side view of an embodiment of a donor plate assembly including multiple heating sources. [Figure 4C] FIG. 4C illustrates a cross-sectional view of an embodiment of a donor plate assembly including multiple heating sources. [Figure 4D] FIG. 4D shows a cross-sectional view of an embodiment of a donor plate assembly including multiple heating sources in electrical contact with a power source. [Figure 5A] FIG. 5A shows a side view of an embodiment of a donor plate assembly including a nanoporous material layer. [Figure 5B] FIG. 5B illustrates a cross-sectional view of an embodiment of a donor plate assembly including a nanoporous material layer. [Figure 6] FIG. 6 shows a top view of an embodiment of a donor plate assembly heated by light injection from the side of the substrate by an array of radiative heating sources. [Figure 7] FIG. 7 illustrates a side view of an embodiment of a donor plate assembly including a light absorbing material. [Figure 8] FIG. 8 shows a side view of an embodiment of a donor plate assembly including a graded light-absorbing material. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] These and other embodiments are provided in greater detail below and throughout the application. An assembly and method for transferring a part using a peelable adhesive layer is discussed in U.S. Patent No. 6,946,178, the contents of which are incorporated herein by reference for all purposes. A triggering process is used to separate the transferred part from the adhesive layer to the substrate. and in U.S. Pat. No. 6,946,178 the triggering process involves exposing the release layer to heat and light in a single step to decompose the release layer.

[0021] In various embodiments of the present disclosure, the release layer is exposed to light and heat from various sources, processes, and / or durations in order to decompose the release layer. Decomposition of the release layer can allow for a process to transfer a component (e.g., a semiconductor component) and / or the component to be transferred. The release layer composition can allow for simultaneous placement of many components on a surface as desired, limited only by how large one wishes to mechanically fasten to the substrate. These components can range in size from microns (e.g., micro LEDs) to centimeters (e.g., large ICs).

[0022] This disclosure describes embodiments that may have capital and / or throughput advantages that may include: 1) reducing the power and energy requirements of the release layer process; 2) reducing or eliminating the need for lasers (except, in some embodiments, optional diodes), at least in the imaging system; 3) improving control of reaction kinetics, including imparting selectable and controllable temperature distributions in space and time; and / or 4) imparting a two-step mechanical implementation in which actinic radiation exposure is separate from chip transfer.

[0023] definition A "release layer" is a layer comprising a polymeric and / or oligomeric material disposed on a substrate (e.g., a donor plate) that allows for the attachment (e.g., adhesion) of components (e.g., semiconductor components) and, when exposed to light and heat, decomposing the release layer and releasing the components, allows for the transfer (e.g., chip transfer) of the components. The release layer can allow for the simultaneous placement of many components on a substrate, if desired, limited only by how large they are to be mechanically fixed to the substrate. These components can range in size from microns (e.g., micro LEDs) to centimeters (e.g., large ICs).

[0024] "Actinic radiation" or "actinic light" is electromagnetic radiation that causes photochemistry in the release layer and decomposes or helps decompose the release layer.

[0025] "Radiative heating" or "optical heating" is electromagnetic radiation that heats the release layer and decomposes or assists in decomposing the release layer.

[0026] "Conduction heating" is heat transfer from physical contact of a source (eg, an electrical heating source) that heats the release layer and breaks down or helps break down the release layer.

[0027] "Pulse period," "pulse length," or "τ" is the period during which a pulse of actinic radiation, radiative heating, and / or conductive heating allows the decomposition reaction of materials in the release layer to proceed to substantial completion so that a component disposed on the release layer can be released and transferred. Gas molecules (e.g., CO and / or HO) may be released from the release layer during the pulse period.

[0028] "Decomposition temperature" or "T sd " is the temperature of the release layer at which the release material decomposition reaction must proceed to substantial completion so that a component disposed on the release layer can be released and transferred. The decomposition temperature of the release layer can vary based on the composition of the material in the release layer.

[0029] overview The use of a release layer as described herein in a transfer process 100 is illustrated in Figure 1. In the process flow shown, a donor plate (A) (e.g., an optically transparent A donor plate (not shown) is applied 102 and coated 104 (e.g., solvent coated) with a film of release layer material composition (B) to form a coated donor plate 106. A desired component (C) to be transferred is then adhered 108 to the release layer (B) of the coated donor plate 106 by contacting the component (C) and release layer (B) with applied pressure and / or heat to form a component-loaded donor plate 110. In some embodiments, the component is attached to a carrier substrate (e.g., tape) before being mounted to the release layer. In some embodiments, a uniform pressure may be applied to the carrier substrate and / or donor plate. In some embodiments, a pressure of 500 N / cm 2 , 1000N / cm 2 , 1500N / cm 2 , 2000N / cm 2 , 2250N / cm 2 , 2500N / cm 2 , 2750N / cm 2 , 3000N / cm 2 , 3250N / cm 2 , 3350N / cm 2 , 3750N / cm 2 or 4000N / cm 2A pressure of about, at most, or at most about 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 1, 1.5, or 2 hours, or any range of values ​​therebetween, is applied to the carrier substrate and / or donor plate. In some embodiments, the pressure may be applied for about, at least, or at least about 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 1, 1.5, or 2 hours, or any range of values ​​therebetween. In some embodiments, while the release layer and the component are in contact for mounting, the release layer may be heated to a temperature of about, at most, or at most about 40° C., 50° C., 60° C., 80° C., 100° C., 110° C., 120° C., 130° C., 140° C., or 150° C., or any range of values ​​therebetween. In some embodiments, the release layer is allowed to cool to room temperature before the pressure is removed.

[0030] In some embodiments, once the components are attached to the release layer, the carrier substrate is removed (e.g., peeled off) to obtain the component-loaded donor plate 110. The component-loaded donor plate 110 is then aligned 112 with the target substrate (D) surface prior to exposure 114 of the release layer (B) to actinic radiation and heat (e.g., radiative and / or conductive heating). In some embodiments, actinic radiation and / or radiative heating of the release layer may be accomplished through an optically transparent donor plate and / or the release layer is directly exposed to actinic radiation and / or radiative heating. The actinic radiation and heating induce a photochemical reaction in the release layer (B) that catalyzes the decomposition of polymeric and / or oligomeric materials into low molecular weight species that are then vaporized to form the components (C) that are released from the donor plate (A) 120. As described herein, actinic radiation and heating 114 may be performed from different sources and, in some embodiments, may be initiated at different, the same, or similar times (e.g., different steps) and / or different, the same, or similar lengths of time (e.g., pulse lengths). Vaporization creates a force that presses the components (C) onto the target substrate (D) 122, where they adhere to the surface to form a component-bearing substrate 124.

[0031] The process illustrated in FIG. 1 relies on the release layer to substantially decompose after exposure to actinic radiation of a particular wavelength and energy (e.g., X-ray, UV, visible, IR) and heating to a decomposition temperature (e.g., about 200° C.), with at least one of the final steps of actinic radiation or heating being performed within a pulse period. In some embodiments, the pulse length (i.e., τ) is about, at most, or at most about 10 ns, 25 ns, 50 ns, 75 ns, 80 ns, 90 ns, 100 ns, 125 ns, 150 ns, 175 ns, 200 ns, 250 ns, 300 ns, 350 ns, 400 ns, 450 ns, 500 ns, 600 ns, 700 ns, 800 ns, 900 ns, 1 μs, 1.2 μs, 1.5 μs, 2 μs, 3 μs, 4 μs, 5 μs, 6 μs, 7 μs, 8 μs, 9 μs, 10 μs, or 12 μs, or any range of values ​​therebetween. In some embodiments, the decomposition temperature (i.e., T sd ) are 100℃, 125℃, 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 225℃, 230℃, 240℃, 250℃, 260℃, 270℃, 275℃, 280℃, 290℃, 300℃, 325℃ or 350° C., or any range of values ​​therebetween, and is about, at least, or at least about such value. In some embodiments, the release layer is a continuous layer disposed over the donor plate. In some embodiments, the release layer can be a patterned release layer comprising multiple release layer elements, each release layer element being separate from the other release layer elements. In the absence of at least one of such light and heat, the release layer maintains chemical integrity and / or good adhesion.

[0032] 2 is a flow chart illustrating an embodiment of a process 200 for decomposing a release layer by heating (e.g., radiatively and / or conductively) the assembly and exposing it to actinic radiation, e.g., actinic radiation and heating step 114 shown in FIG. 1. An assembly including a release layer is provided 202 and may first be heated above a decomposition temperature 204a and then subsequently exposed to actinic radiation in a pulsed period 204b, thereby causing decomposition of the release layer 210. Alternatively, the assembly including a release layer 202 may first be exposed to actinic radiation 206a and then subsequently heated above a decomposition temperature 206b in a pulsed period 210, thereby causing decomposition of the release layer. In another embodiment, the assembly including a release layer 202 may simultaneously be heated above a decomposition temperature and exposed to actinic radiation 208, thereby causing decomposition of the release layer 210, with at least one of the heating and the actinic radiation being performed in a pulsed period.

[0033] FIG. 3 is a flow chart illustrating an embodiment of a process 300 for decomposing a release layer polymeric and / or oligomeric material by heating (e.g., radiative and / or conductive heating) an assembly and exposing it to actinic radiation, where a heating step below the material decomposition temperature and a heating step above the material decomposition temperature are performed. In some embodiments, the heating step below the decomposition temperature is performed by radiative heating and the heating step above the decomposition temperature is performed by conductive heating. In some embodiments, the heating step below the decomposition temperature is performed by conductive heating and the heating step above the decomposition temperature is performed by radiative heating. In some embodiments, both heating steps are radiative heating. In some embodiments, both heating steps are conductive heating. An assembly including a release layer is applied 302 and may first be heated below the decomposition temperature 304a, then may be subsequently exposed to actinic radiation 304b, and then may be subsequently heated above the decomposition temperature within a pulse period 304c, thereby causing decomposition of the release layer 310. Alternatively, the assembly 302 including the release layer may be first exposed to actinic radiation 306a, then subsequently heated to below the decomposition temperature 306b, then subsequently heated to above the decomposition temperature in a pulsed period 306c, thereby causing decomposition of the release layer 310. In another embodiment, the assembly 302 including the release layer may be first heated to below the decomposition temperature 308a, then subsequently heated to above the decomposition temperature 308b, then subsequently exposed to actinic radiation in a pulsed period 308c, thereby causing decomposition of the release layer 310. In some embodiments, actinic radiation exposure may be combined with heating below the decomposition temperature or heating above the decomposition temperature (e.g., steps 304a and 304b are combined, steps 304b and 304c are combined, steps 306a and 306b are combined, steps 308b and 308c are combined).

[0034] In some embodiments, the assembly (e.g., donor plate and / or release layer) is heated to a first temperature and then heated to a second temperature. In some embodiments, the first temperature is at, about, below, or below the material decomposition temperature. In some embodiments, the first temperature is at, about, above, or above the material decomposition temperature. In some embodiments where the first temperature is at, about, above, or above the material decomposition temperature, the assembly is cooled to below the material decomposition temperature before being heated to the second temperature. In some embodiments, the second temperature is The first temperature is at, about, above, or about the material decomposition temperature. In some embodiments, the first temperature is at, about, greater than, or greater than about 40° C., 50° C., 60° C., 70° C., 80° C., 90° C., 100° C., 125° C., 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., 210° C., 220° C., 225° C., 230° C., 240° C., 250° C., 260° C., 270° C., or 275° C., or any range of values ​​therebetween. In some embodiments, the second temperature is about, at least, or at least about 100°C, 125°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 225°C, 230°C, 240°C, 250°C, 260°C, 270°C, 275°C, 280°C, 290°C, 300°C, 325°C, or 350°C, or any range of values ​​therebetween.

[0035] In some embodiments, the actinic radiation and heating of the release layer may be initiated at different, the same, or similar times (e.g., different steps) and / or different, the same, or similar lengths of time (e.g., pulse lengths). In some embodiments, the actinic radiation may be initiated before, simultaneously with, and / or after heating. In some embodiments, the length of time the release layer is exposed to the actinic radiation may fully overlap, partially overlap, or not overlap with the length of time the heating is performed (e.g., the actinic radiation and heating steps are performed sequentially or with a delay between steps). For example, in some embodiments, the heat required to achieve the decomposition temperature is applied to the release layer during a pulse period, and the actinic radiation may be provided to the release layer on any time scale (e.g., before, after, and / or during heating). In another example, in some embodiments, the release layer may be heated continuously to the required temperature, and the actinic radiation may be provided to the release layer during a pulse period (e.g., before, after, and / or during heating). It should be understood that in some embodiments, any intermediate combination of the two examples discussed above may be possible. For example, in some embodiments, the release layer may be at least partially attenuated by T for a period longer than τ. sd (e.g., about 180° C.) and then heated to a value less than T sd The release layer may be further heated (e.g., to about 200° C.) and actinic radiation may be provided to the release layer on any time scale (e.g., before, after, and / or during at least one of the heating steps).

[0036] Decomposing the release layer (e.g., a patterned release layer) includes exposing the release layer to actinic radiation and heat from different sources. In some embodiments, at least one of actinic radiation and heating can be performed by exposing the release layer to light. In some embodiments, the release layer is exposed to light from the release layer-facing side of the assembly or through the donor plate-facing side of the assembly. In embodiments, when light is directed toward the release layer-facing side of the assembly, the donor plate may be opaque or at least partially transparent. In embodiments, when light is directed directly through the donor plate, the donor plate is at least partially transparent at least to the wavelength range of the light to which it is exposed. In some embodiments, the donor plate is opaque or non-transparent, radiant heating light is directed toward the donor plate, and the heated donor plate conductively heats the release layer.

[0037] In some embodiments, the release layer (e.g., a patterned release layer) is configured to control the peel speed and / or trajectory of the parts as the release layer is decomposed to release the parts. In some embodiments, the at least one released part has a peel speed of about, at most, or at most about 0.1 m / s, 0.3 m / s, 0.5 m / s, 0.8 m / s, 1 m / s, 2 m / s, 3 m / s, 4 m / s, 5 m / s, 6 m / s, 8 m / s, or 10 m / s, or any range of values ​​therebetween. In some embodiments, the release layer is configured to control the peel speed and / or trajectory of the parts as the release layer is decomposed to release the parts ... When one component is peeled, it is configured to flip-chip at least one component, and the peel speed and / or trajectory can be controlled in a variety of ways, similar to the control over rotation, for example, by asymmetric positioning of the components and / or use of shaped charge release layer element(s).

[0038] In some embodiments, the release layer (e.g., a patterned release layer) includes voids and / or escape channels. In some embodiments, gas products are configured to flow through the escape channels when the release layer decomposes. In some embodiments, the voids and / or escape channels are configured to control or help control the speed and / or trajectory of the release component when the release layer decomposes. In some embodiments, the escape channels are configured to control or help control the orientation and / or rotation of the component (e.g., flip chip) when the release layer decomposes.

[0039] In some embodiments, the heating generates heat on one side of the release layer, away from the release surface. In some embodiments, the pulse spreads over 0.5 μm in about 1 μs. Thus, the temperature is non-uniform during some percentage of the reaction (after 10 μs, the diffusion distance is still only 1.4 μm). In some embodiments, a thinner film of the release layer may achieve higher heat uniformity. In some embodiments, a thin film of conductive heating source alone may cause the release layer adjacent to this layer to have a higher temperature than the release layer adjacent to the part or the release layer further away from the conductive heating source. In some embodiments, the release layer film may have a gradient of photosensitizer (e.g., photoacid generator ("PAG")) that sensitizes the polymer and / or oligomer to aid in decomposition, with a lower concentration at the top and a higher concentration at the lower part cast after the first time. The decomposition reaction rate depends on the catalyst concentration as well as the temperature, so in some embodiments, the gradient may aid in uniformly peeling the part from the release layer. In some embodiments, the heating source is disposed on an additional polymer layer having a lower thermal conductivity than the polymeric and / or oligomeric material in the release layer. In some embodiments, the additional polymer comprises a nanoporous polymer having a low density. In some embodiments, the release layer is thinner (e.g., on the order of <1 μm or even hundreds of nm). In some embodiments, the additional polymer layer helps to create a uniform temperature of the release layer when heated.

[0040] In some embodiments, the entire apparatus, including the substrate (e.g., donor plate), release layer, and components, and the fixtures holding these elements, can be mounted in a T sd It may be heated to a nearby stable temperature and then photochemistry is initiated by radiative heating and / or a rapid light pulse of actinic radiation.

[0041] In some embodiments, the disclosed processes advantageously allow for the use of photobleachable masks (e.g., based on substituted anthracenes). In some embodiments, the photobleachable masks absorb strongly in the near UV (about 360-380 nm), much more strongly around 260 nm, but do not absorb at or near 300 nm. In some embodiments, irradiation (e.g., laser and / or diode irradiation) may be performed at wavelengths shorter than 300 nm (e.g., about 266 or 248 nm). Additionally, in some embodiments, the processes disclosed herein may allow the possibility of using other photoactive sensitizers (e.g., PAGs) without worrying about specific laser or diode frequencies. In some embodiments, photoactive sensitizers (e.g., PAGs) that operate in the near UV may be utilized, such that anthracene chemistry may be used directly. In some embodiments, sensitization may be utilized.

[0042] Release layers, compositions and compounds The composition of the release layer includes an oligomeric and / or polymeric composition that may include oligomeric and / or polymeric components that include units containing a tetralin or cyclohexene core and linkers connecting the core to other cores and / or portions of the composition.

[0043] In some embodiments, the release layer composition comprises a polymeric material. In some embodiments, the release layer composition comprises a polymeric component intermixed with an oligomeric component. In some embodiments, the polymeric component forms a homogeneous film with the oligomeric component. In some embodiments, the polymeric component comprises multiple polymers. In some embodiments, the polymeric component can be used in an amount effective to adjust the material properties and / or release properties of the release layer film. In some embodiments, the polymeric component comprises a linear homopolymer, a block copolymer, a polymer network, and the like. In some embodiments, the polymeric component acts as a matrix to support the oligomeric component and dictates the physical and / or optical properties of the release layer. Tailoring the material properties of the release layer by modifying the polymeric component can be advantageous because the properties of the release layer can be altered on an application basis without the need to redesign the oligomeric component. Additionally, different polymers can alter the processing conditions for adhering the part to the release layer. Also, the network polymer can help trap non-volatile residues that are transferred during outgassing. In some embodiments, the polymeric component is photochemically inert. In some embodiments, the polymeric component is photochemically active. Examples of possible polymer components include: polymer components containing a tetralin or cyclohexene core and linkers, polypropylene, poly(propyl carbonate), polyurethane, ABS block copolymers, polyester, polyvinyl chloride, polystyrene, copolymers thereof, and combinations thereof. An example of a network polymer could be a polyethylene glycol polymer that is crosslinked by thiolene photochemistry after deposition on a donor substrate.

[0044] In embodiments of the release layer compositions described herein, the decomposition material (e.g., oligomeric component) is the major component (i.e., the component that constitutes the largest weight or mass %) of the release layer formulation. In embodiments of the release layer compositions described herein, the decomposition material (e.g., oligomeric component) is a minor component of the release layer formulation. For example, in embodiments, the polymeric component may be the major component of the release layer, while the oligomeric component is the minor component. In some embodiments, the release layer composition comprises 1 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, 95 wt%, or 98 wt%, or any range of values ​​therebetween, comprises about such value of oligomeric component, comprises at least such value of oligomeric component, comprises at least about such value of oligomeric component, comprises at most such value of oligomeric component, or comprises at most such value of oligomeric component. In some embodiments, the release layer composition comprises 1 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, 95 wt%, or 98 wt%, or any range of values ​​therebetween, comprises about such value of the polymer component, comprises at least such value of the polymer component, comprises at most such value of the polymer component, or comprises at most such value of the polymer component.

[0045] When the chemical bonds in the oligomeric and / or polymeric linkages are cleaved through the application of heat and actinic radiation, the remainder of the linkages are converted to relatively volatile, non-reactive small molecules. The gaseous by-products are then released through a volume expansion that presses the bonded parts onto the target substrate. As described herein, the oligomeric and / or polymeric compound linkages may be cleaved by application of heat (radiative and / or conductive) and actinic radiation. In some embodiments, the oligomeric and / or polymeric compound may be heated directly and / or indirectly through heating of another layer disposed at or near the release layer (e.g., substrate) and / or heating of an element within the release layer composition. For example, in some embodiments, the tetralin core is an aromatic chromophore that may facilitate film heating by radiative heating (e.g., by a laser) with wavelengths in the range of approximately 240-300 nm. The cyclohexene core may be heated indirectly through radiative heating of a compound within the film that acts as a chromophore having a wavelength absorbed by the chromophore.

[0046] In some embodiments, the decomposed core may be converted to a non-reactive and volatile product. For example, a carbonate linkage attached to the benzylic position of tetralin (i.e., tetrahydronaphthalene) will convert the tetrahydronaphthalene core to a non-reactive and volatile naphthalene when the carbonate is cleaved. This also drives the decomposition reaction to completion due to the formation of an aromatic system. As another example, benzylic carbonates (e.g., oligomeric or polymeric components having tetralin (i.e., tetrahydronaphthalene) units and carbonate linkages) may be advantageous because the benzylic functionality stabilizes the cationic intermediate of carbonate cleavage and may result in a much faster and lower energy cleavage type reaction. As a further example, a bis-carbonate core (i.e., an oligomeric or polymeric moiety having tetralin (i.e., tetrahydronaphthalene) or cyclohexene linked to two carbonate linkages) may be advantageous because cleavage of the two carbonates results in the formation of two C=C bonds, thereby resulting in a fully aromatic structure. The formation of an aromatic structure may help drive rapid linkage cleavage and gas formation.

[0047] In some embodiments, the release layer composition includes a photoactive sensitizer. In some embodiments, the photoactive sensitizer may be a thermal sensitizer, a photoacid generator ("PAG"), and combinations thereof. In various embodiments, the release layer composition includes a thermal sensitizer in the form of one or more additives that absorb radiant heating light and convert it to heat. The thermal sensitizer may have a high photon absorption quantum yield, a low fluorescence / phosphorescence quantum yield, and / or a short excited state lifetime that decays through a non-irradiative pathway. They may be used in an effective amount to increase the rate of linkage decomposition and gas formation by aiding the heating rate during radiative heating. These agents may also facilitate heating with lower power and longer wavelength lasers. In some embodiments, the thermal sensitizer will form a homogenous film with the release layer formulation. In some embodiments, the thermal sensitizer will form a transparent film with the release layer formulation. In some embodiments, the thermal sensitizer will form an opaque film with the release layer formulation. Examples of thermal sensitizers include, in some embodiments, inorganic agents, gold plasmonic nanoparticles, silver plasmonic nanoparticles, gold nanowires, silver nanowires, carbon-based agents, carbon nanotubes, carbon black, graphene, graphene oxide, organic agents, and metal formulations. In some embodiments, the organic thermal sensitizers include one or more of the following structural features: aromaticity, fused polycyclic ring systems, S- or N-containing heterocycles, polycyclic ring systems, and / or polyaromatic systems. Examples of organic thermal sensitizers include melamine, eumelanin, indole, pyrrole, quinoline, purine, triphenylmethyl compounds (e.g., (methoxymethanetriyl)tribenzene), fused aromatic compounds (e.g., anthracene and pyrene), dibenzothiophene, thiophene, and derivatives thereof.

[0048] In various embodiments, the release layer composition includes a photoacid generator (PAG). In some embodiments, the PAG includes a chromophore unit and an acid precursor unit. In some embodiments, the chromophore unit includes diphenyliodonium, triphenylsulfonium, and the like. In some embodiments, the acid precursor unit is selected from trifluoromethanesulfonate (i.e., triflate), hexafluorophosphate, nitrate, p-toluenesulfonate, perfluoro-1-butanesulfonate, and combinations thereof. In some embodiments, the PAG is an ionic PAG or a non-ionic PAG. In some embodiments, the ionic PAG is selected from diphenyliodonium nitrate, bis(4-tert-butylphenyl)iodonium perfluoro-1-butanesulfonate, bis(4-tert-butylphenyl)iodonium p-toluenesulfonate, (4-phenylthiophenyl)diphenylsulfonium triflate, triarylsulfonium hexafluorophosphate, and combinations thereof. In some embodiments, the non-ionic PAG is selected from N-hydroxynaphthalimide triflate, N-hydroxy-5-norbornene-2,3-dicarboximide perfluoro-1-butanesulfonate, 2-(4-methoxystyryl)-4,6,-bis(trichloromethyl)-1,3,5-triazine, and combinations thereof. In some embodiments, the PAG is (4-phenylthiophenyl)diphenylsulfonium trifluoromethanesulfonate.

[0049] In another embodiment, additives that absorb radiant heating light and convert it into heat can be the main component of the release layer. They may be used in an effective amount to increase the rate of oligomer and / or polymer decomposition and gas formation by aiding the heating rate during radiant heating. These agents can also facilitate heating with lower power and longer wavelength lasers. Examples of additives include colloidal metals, Si, SiO2, TiO2, SnO2, anthracene, naphthalene, dimethoxybenzene, tetrahydronaphthalene, diphenyl ether, phenylcyclohexane, tert-butylphenol, acetoxy-tetrahydronaphthalene, and derivatives thereof. In some embodiments, the additive is configured to absorb at a wavelength that is about, at most, at most about, at least, or at least about 300 nm, 320 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 950 nm, 1000 nm, 1100 nm, 1300 nm, or 1500 nm, or any range of values ​​therebetween.

[0050] Actinic radiation Actinic radiation of the release layer is used to generate photochemistry in the release layer that decomposes or helps decompose the release layer. In some embodiments, the wavelength of actinic radiation used to decompose or help decompose the release layer (i.e., the release wavelength) is UV light, visible light, or a combination thereof. In some embodiments, the wavelength of actinic radiation used to decompose or help decompose the release layer (i.e., the release wavelength) is 180 nm, 200 nm, 210 nm, 220 nm, 230 nm, 240 nm, 250 nm, 260 nm, 270 nm, 280 nm, 290 nm, 300 nm, 310 nm, 320 nm, 330 nm, 340 nm, 350 nm, 360 nm, 370 nm, 380 nm, 390 nm, 400 nm, or 450 nm, or any value in between, or about such value. In some embodiments, actinic radiation sources include LEDs, lasers (e.g., diode lasers, solid state lasers, gas lasers, liquid lasers, and fiber lasers), and combinations thereof. In some embodiments, actinic radiation may be applied in pulsed and / or continuous wave configurations. In some embodiments, the pulsed actinic radiation is 0.3 ns, 0.5 ns, 0.7 ns, 0.8 ns, 0.9 ns, 1 ns, 3 ns, 5 ns, 8 ns, 10 ns, 25 ns, 50 ns, 75 ns, 80 ns, 90 ns, 100 ns, 125 ns, 150 ns, 175 ns, 200 ns, 250 ns, 300 ns, 350 ns, 400 ns, 450 ns, 500 ns, 600 ns, 700 ns, 800 ns, 900 ns, 1 μs, 1.2 μs, 1.5 μs, 2 μs, 3 μs, 4 μs, 5 μs, 6 μs, 7 μs, 8 μs, 9 μs, 10 μs, or 12 μs, or any range of values ​​therebetween. In some embodiments, the pulse width of the pulsed actinic radiation is a pulse duration, about a pulse duration, at most a pulse duration, or at most about a pulse duration. In some embodiments, the actinic radiation is administered for a pulse duration, about a pulse duration, at most a pulse duration, or at most about a pulse duration. In some embodiments, the energy density of the actinic radiation is 4 mJ / cm 2, 5mJ / cm 2 , 6mJ / cm 2 , 8mJ / cm 2 , 10 mJ / cm 2 , 20mJ / cm 2 , 30mJ / cm 2 , 40mJ / cm 2 , 45mJ / cm 2 , 50mJ / cm 2 , 60mJ / cm 2 , 70mJ / cm 2 , 75mJ / cm 2 , 80mJ / cm 2 , 90mJ / cm 2 , 100mJ / cm 2 , 125mJ / cm 2 , 150mJ / cm 2 , 175mJ / cm 2 or 200mJ / cm 2 , or any range of values ​​therebetween, and may be about, at least, or at least about such value.

[0051] Although the main purpose of the actinic radiation is to cause photochemistry in the release layer, some of the actinic radiation may nevertheless be absorbed by the compounds in the release layer composition and converted to heat. Such heat conversion of actinic radiation may be minimized by the selection of the wavelength and power density of the actinic radiation and / or the selection of the compounds (e.g., polymer and photoactive sensitizer) of the release layer composition. In some embodiments, the polymer of the release layer composition absorbs actinic radiation in an amount of about, at least, or at least about such value, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 95%, or any range of values ​​therebetween. In some embodiments, the photoactive sensitizer of the release layer composition absorbs actinic radiation in an amount of about, at most, or at most about such value, 1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 40% or 50%, or any range of values ​​therebetween. In some embodiments, actinic radiation is absorbed mostly by the polymer of the release layer composition and may not be absorbed or is minimally absorbed by the photoactive sensitizer.

[0052] By way of example, an incident Q-switched Nd:YAG laser pulse may be utilized, with a pulse width of 0-10 μs (e.g., 0-10 ns) of approximately 50 mJ / cm that is useful for producing reactions that decompose or help decompose the release layer. 2 In some embodiments, depending on the laser, the laser wavelength of light, the laser pulsing frequency, and the laser power (more or less than about 50 mJ / cm 2 In some embodiments, less than 50 mJ / cm at an incident laser pulse at 266 nm may be utilized. 2 Only about 30-70% of the absorbed actinic radiation (e.g., light) is absorbed (depending on film thickness). In some embodiments, a fraction of the absorbed actinic radiation (e.g., light) is converted to heat and a percentage is converted to light emission, the yield is unknown but is probably about 20%. This translates to about 20 mJ / cm of heat. 2 It is suggested that 10 ns pulses of 1000 uV enter the polymer. Some of this may be lost to thermal diffusion. 2 Using the simple formula = 2Dt, the penetration distance of a heat pulse through polycarbonate is 0.5 μm at 1 μs and 1.4 μm at 10 μs. The diffusion length in fused silica is 1.3 μm at 1 μs. Without diffusion, 15 mJ / cm2 instantly deposited in polycarbonate 2 can heat it by about 115 K. The required energy is 15 mJ / cm 2 Then, a 20cm x 20cm donor plate (400cm 2 The total energy for the 1000 kW pulse is 6 J. The maximum power output is 600 kW (1.5 kW / cm) when delivered in 10 μs. 2 ) The actual amount needed in practice may be larger due to diffusion losses, but may be smaller when applied in a temporally optimized manner. These numbers set "reasonable goals" for the laser pulses, but are not intended to stipulate explicit requirements.

[0053] Conduction heating The release layer may be heated through conductive heating (e.g., an electrical heating source) to decompose or aid in the decomposition of the release layer. In some embodiments, conductive heating is applied directly to the release layer. In some embodiments, conductive heating is applied to a substrate (e.g., a donor plate), which then conductively heats the release layer.

[0054] In some embodiments, a specific amount of heating energy is delivered to the release layer. In some embodiments, conductive heating (e.g., electrical heating) is performed for a short period (e.g., microseconds) with rapid onset (e.g., <1 μs). In some embodiments, conductive heating is performed for a pulse period, about a pulse period, as long as a pulse period, or as long as about a pulse period. In some embodiments, slow actinic radiation exposure (e.g., beyond the pulse period) may be performed on the release layer before, after, or simultaneously with heating to cause or assist in decomposition (e.g., sensitization) of the release layer. In some embodiments, conductive heating (e.g., electrical heating) is performed within the pulse period to cause or assist in causing the release layer to drop and form a pulse of gas to release (e.g., press) the part from the substrate (e.g., donor plate). In some embodiments, conductive heating performed within the pulse period prevents gas from escaping quickly and exerting a force on the part and / or gas from escaping slowly and without exerting a force on the part. In some embodiments, the release of the part (e.g., the transfer reaction) may not be significantly affected by how quickly the heat is turned off once the release layer decomposition is complete. In some embodiments, the speed at which the heat is turned off may be a consideration for substrate (e.g., donor plate) heating. In some embodiments, the heat may be applied directly to a thin film (e.g., 1 μm thick) of the release layer, and a relatively small amount of the substrate (e.g., on the order of 1 mm or more in thickness) may be heated. In some embodiments, the duty cycle of the heating source may be small (e.g., on the order of 10 -5 s on, approx. 1-10s off).

[0055] In some embodiments, the conductive heating source is an electric heating source. In some embodiments, the electric heating source may include a conductive and resistive material (e.g., a thin film of material) and pass an electric current through the material for a desired time scale to heat the material. In some embodiments, the conductive heating source is disposed on (e.g., disposed on) at least one surface of the substrate (e.g., donor plate) that includes the release layer. In some embodiments, the conductive heating source is disposed on at least one of the top major surface (i.e., the same surface on which the release layer is disposed), the bottom major surface (i.e., the surface opposite to that on which the release layer is disposed), or the side surface. In some embodiments, the conductive heating source (e.g., an electrical conductor) is in electrical communication with a power source. In some embodiments, the conductive heating source is in electrical communication with a power source having electrodes that wrap around one or more edges of the substrate (e.g., donor plate). In some embodiments, the electrode leads may be covered by another metal (e.g., gold, platinum, copper, nickel) (e.g., for protection and / or lower contact resistance). In some embodiments, the power source is in electrical communication (e.g., in contact) with a metal (e.g., a precious metal) using brushes (e.g., as used in electric motors) or in physical contact. In some embodiments, the conductive heat source is transparent or partially transparent (i.e., a transparent conductive heat source) to the wavelength of interest (e.g., actinic radiation wavelengths (e.g., deep UV wavelengths) and / or light heating wavelengths). In some embodiments, the wavelength of interest is 180 nm, 200 nm, 210 nm, 220 nm, 230 nm, 240 nm, 250 nm, 260 nm, 270 nm, 280 nm, 290 nm, 300 nm, 310 nm, 320 nm, 330 nm, 340 nm, 350 nm, 360 nm, 370 nm, 380 nm, 390 nm, 400 nm, or 450 nm, or any range of values ​​therebetween, or about such value. In some embodiments, a transparent conductive heat source exhibits a transmittance at a wavelength of interest of about, at least, or at least about 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90% or 95%, or any range of values ​​therebetween.In some embodiments, the sheet resistance of the conductive heat source ("R s ”) are 5Ω / □, 10Ω / □, 15Ω / □, 20Ω / □, 25Ω / □, 30Ω / □, 35Ω / □, 45Ω / □, 45Ω / □, 50Ω / □, 55Ω / □, 60Ω / □, 70Ω / □, 80Ω / □, 90Ω / □, 100Ω / □, 150Ω / □, 200Ω / □, 250Ω / □, 300Ω / □, 400Ω / □, 500Ω / □, 600Ω / □, 700Ω / □, 800Ω / □, 900Ω / □, 1000Ω / □, 1200Ω / □ or 1500Ω / □, or any range of values ​​therebetween, and is about, at most, or at most about such value. In some embodiments, the conductive heat source has a thickness of about, at most, or at most about 3 nm, 4 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 80 nm, 85 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 150 nm, 175 nm, 200 nm, 250 nm, 300 nm, 400 nm, 500 nm, or 1000 nm, or any value therebetween. In some embodiments, the transparent conductive heat source comprises a transparent conductive oxide ("TCO"). In some embodiments, the TCO includes indium tin oxide ("ITO") (e.g., textured ITO), β-Ga2O3, gold (Au), silver (Ag), and La-doped SrSnO3. In some embodiments, the TCO includes indium tin oxide ("ITO") (eg, textured ITO), β-Ga2O3, gold (Au), and La-doped SrSnO3.

[0056] 4A-4D show an embodiment of a donor plate assembly including multiple heat sources. FIG. 4A shows an assembly 400A including a donor plate 402 and at least one heat source strip 404, where multiple heat source strips 406 are provided on the donor plate 402. The multiple heat source strips 406 are shown separated from one another by a strip distance 408, and each heat source strip 404 is shown having a width 410. At a distal end of the donor plate 402 and multiple heat source strips 406, a distal bus bar 412 is provided on the donor plate 402 and multiple heat source strips 406, and at a proximal end of the donor plate 402 and multiple heat source strips 406, a proximal bus bar 414 is provided on the donor plate 402 and multiple heat source strips 406. Distal busbar 412 is shown with top busbar portion 412a disposed on a distal end of the top major surface of donor plate 402 and side busbar portion 412b disposed on a distal side edge of donor plate 402. Width 416 of top busbar portion 412a is also shown. FIG. 4B shows a side view of assembly 400B including donor plate 422 and at least one heating source 424, with multiple heating sources 426 disposed on donor plate 422. FIG. 4C shows a cross-sectional view of assembly 400C including donor plate 432, heating source 434 disposed on donor plate 432, and busbar 444 disposed on heating source 434 and the top, side and bottom major surfaces of donor plate 432. Also shown is a width 446 of busbars 444 on the top major surface of donor plate 432 and a thickness 448 of busbars 444 on the side edges of donor plate 432. Figure 4D shows a cross-sectional view of assembly 400D including donor plate 452, a heating source 454 on donor plate 452, and busbars 464 on the heating source 454 and the top, side and bottom major surfaces of donor plate 452, and devices 466 in electrical contact 468 (e.g., by use of springs and / or brushes) with busbars 464. The devices are shown in electrical communication with a power source 470.

[0057] In some embodiments, the busbar comprises a metal, such as Au and / or Pt. In some embodiments, the busbar is deposited on the donor plate and the heating source, such as by plating and / or evaporation. In some embodiments, the donor plate is about, at most, or at most about 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, or 10 mm thick, or any range of values ​​therebetween. In some embodiments, the heating source (e.g., TCO) is about 10 nM thick. In some embodiments, the distance between adjacent heating sources is about, at least, or at least about 50 nm, 75 nm, 100 nm, 125 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, or 700 nm thick, or any range of values ​​therebetween. In some embodiments, the width of the heating source strips is about, at least, or at least about 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 10 μm, 50 μm, 100 μm, 500 μm, 1 mm, or 5 mm, or any value in between. In some embodiments, the width of the bus bars disposed on the top major surface of the donor plate is about, at most, or at most about 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, or 8 mm, or any value in between. In some embodiments, the thickness of the busbars disposed on the side edge surfaces of the donor plate is about, at most, or at most about 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, or 8 μm, or any range of values ​​therebetween.

[0058] 5A and 5B show an embodiment of a donor plate assembly including a nanoporous material layer. FIG. 5A shows a side view of assembly 500A including donor plate 502, nanoporous material layer 504 disposed on donor plate 502, multiple heating sources 506 disposed on donor plate 502 and nanoporous material layer 504, bus bars 508 disposed on multiple heating sources 506, and a release layer 510 disposed on bus bars 508. FIG. 5B shows a cross-sectional view of assembly 500B including donor plate 522, nanoporous material layer 524 disposed on donor plate 522, heating sources 526 disposed on nanoporous material layer 524, bus bars 528 disposed on heating sources 526, and a release layer 530 adjacent to bus bars 508 and disposed on heating sources 526. Bus bars 528 are shown disposed on the top major surface, side edge surfaces, and bottom edge surfaces of donor plate 522. The width 534 of the busbars 528 on the top major surface of the donor plate 522 and the thickness 532 of the busbars 528 on the side edge surfaces of the donor plate 522 are also shown.

[0059] Conductive heating requirements (e.g., electrical requirements) may depend on how the heating is performed. There are three ranges to consider: static, real-time, and mixed.

[0060] Radiant heating The release layer may be heated through radiative heating (e.g., an IR heating source) that decomposes or helps decompose the release layer. For example, in some embodiments, a certain amount of heating energy is delivered through a photoheating current with, before, or after the second actinic radiation exposure to cause photochemistry to decompose the release layer.

[0061] The spectrum of electromagnetic radiation may be divided into UV, IR, visible and microwave regions for this purpose. The UV spectrum may be further divided into near UV (e.g., about 300-400 nm), mid UV (e.g., about 200-300), and far UV (e.g., about 100-200). The IR spectrum may be further divided into near IR (e.g., about 800-2000 nm), mid IR (e.g., about 2-10 μm), and far IR (e.g., about 10 μm-1 mm). In some embodiments, radiative heating may be performed in the UV (e.g., near UV, mid UV and / or far UV), IR (e.g., near IR, mid IR and / or far IR), visible or microwave regions, or any combination of these regions. Some In embodiments, radiative heating may be performed in the mid-IR range. In some embodiments, radiative heating may be performed at wavelengths of 280 nm, 300 nm, 310 nm, 320 nm, 330 nm, 340 nm, 350 nm, 360 nm, 370 nm, 380 nm, 390 nm, 400 nm, 425 nm, 450 nm, 475 nm, 500 nm, 525 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 1000 nm, 1100 nm, 1200 nm, 1500 nm, 1600 nm, 1700 nm, 1800 nm, 1900 nm, 2000 nm, 2100 nm, 2200 nm, 2300 nm, 2400 nm, 2500 nm, 2600 nm, 2700 nm, 2800 nm, 2900 nm, 3000 nm, 3100 nm, 3200 nm, 3300 nm, 3400 nm, 350 nm, 360 nm, 370 nm, 380 nm, 390 nm, 400 nm, 425 nm, 450 nm, 475 nm, 500 nm, 525 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 1000 nm, 1100 nm, 1200 nm, 1300 nm, 1400 nm, 1500 nm, 1600 nm, 1700 The radiation heating may be performed using a wavelength of about, at least, or at least about 0 nm, 2000 nm, 2500 nm, 3000 nm, 3500 nm, 4000 nm, 5000 nm, 6000 nm, 7000 nm, 8000 nm, 9000 nm, 10000 nm, 12000 nm, 15000 nm, 20000 nm, 30000 nm, 50000 nm, 75000 nm, or 100000 nm, or any value therebetween. In some embodiments, the radiation heating may be performed in the IR range (e.g., the mid-IR range). In some embodiments, microwaves may be used for the radiation heating, and may be relatively strongly absorbed at certain wavelengths.

[0062] In some embodiments, at least some of the radiative heating is absorbed by the substrate material (e.g., silicon, silica, and BaF2). For example, silicon begins to absorb significantly at wavelengths above 5 μm. 10.6 μm light is absorbed within a few microns at the surface of fused silica. Thus, in some embodiments, 10.6 μm radiative heating light may be applied to a fused silica substrate in a continuous wave (cw) form to heat the substrate. In some embodiments, the substrate comprises multiple substrate materials and / or layers. For example, in some embodiments, a fused silica layer may be deposited on a BaF2 donor plate substrate and used as an exothermic thin film (e.g., by CO2 laser radiation). In some embodiments, such a fused silica layer on BaF2 configuration may utilize radiative heating in a pulsed mode of operation, since heat does not have to diffuse throughout the substrate as may be necessary for a fused silica donor plate substrate. As an example, in some embodiments, a pulsed system requires approximately 20 mJ / cm2 to produce a temperature jump of 200° C. at the surface of the film. 2 is calculated and decreases through the film thickness. This heat is quickly lost by diffusion if it is dosed very quickly (e.g., 5 ns). Therefore, in some embodiments, either longer exposure periods or multiple doses may be utilized. 20 mJ / cm2 in a 20×20 cm donor plate stretched over 1 ns 2 Note that the power dissipation is 8 MW. Another example is that in some embodiments, in a purely cw system, the DP essentially acts as a hotplate, resulting in a power dissipation rate similar to that which occurs when raising the surface temperature of a laboratory hotplate to 200° C., which is roughly 1 kW (at 20×20 cm).

[0063] In some embodiments, at least some of the radiative heating is absorbed by the release layer. In some embodiments, the radiative heating wavelength is selected to be absorbed and heat the polymer of the release layer composition. In some embodiments, the absorption of the polymer in the UV (e.g., near UV, mid UV and / or far UV) is selected for radiative heating. In some embodiments, the polymer has strong absorption in the near UV and weaker absorption in the mid UV (e.g., about 300 nm) and / or far UV. In some embodiments, the monomers (e.g., carbonate monomers) of the polymer of the release layer have absorbance in the near UV and / or mid UV (e.g., about 300 nm).

[0064] In some embodiments, the radiative heating wavelengths (e.g., UV) are absorbed by the components (e.g., Si components, GaN components, SiC components, AlP components, and / or GaAlInP components) disposed on the exfoliation layer. For example, silicon (Si) absorbs strongly at about 375 nm (α about 10 5 cm -1 GaN absorbs at about 355 nm. In some embodiments, the gallium nitride quantum wells have at least some absorption near 6-7 μm. It has near-IR absorption. In some embodiments, laser diodes (LDs) (e.g., high power LDs) may be used for radiative heating (e.g., at about 375 nm). In some embodiments, arrays may be constructed with high enough resolution to address individual components (e.g., chiplets). Typical commercially available laser diodes have large heat removal structures that may make them unsuitable for heating components, but in some embodiments, LDs may be used with low duty cycles (e.g., on for about 10 μs, then off for 1-10 s) to avoid the need for heat removal structures. GaN is transparent above about 360 nm and at this wavelength, but different reports indicate slightly different cut-on frequencies that may be due to purity. In some embodiments, a diode-pumped YAG laser at 355 nm may be utilized (e.g., to optically heat GaN). In some embodiments, a diode-pumped YAG laser may advantageously have simpler optics (e.g., imaging is not required). For example, in some embodiments, a 355 nm YAG or 351 nm YAG laser may be used. XeF excimers may be utilized to produce strong absorption near the surface of GaN components (eg, LED components) or Si components, with Si absorbing approximately 10x stronger than GaN at 355 nm.

[0065] In some embodiments, the wavelengths for radiative heating are selected to avoid causing or assisting in causing photochemistry. In some embodiments, the wavelengths for radiative heating do not overlap or do not substantially overlap with the wavelengths for actinic irradiation. The overlap of the wavelengths for radiative heating and actinic irradiation may be the integrated area under the spectral emission curve of the weaker source relative to the stronger source in the spectral region where they overlap, the spectral emission curves being calibrated as energy / unit area / unit time. In some embodiments, the overlap between the wavelengths for radiative heating and actinic irradiation is about, at most, or at most about such value, 25%, 20%, 15%, 10%, 8%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, or 0%, or any value therebetween. In some embodiments, the overlap between the full width at half maximum (FWHM) wavelength of the radiative heating and the FWHM wavelength of the actinic radiation is about, at most, or at most about 25%, 20%, 15%, 10%, 8%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, or 0%, or any value therebetween. In some embodiments, the wavelength for radiative heating is selected to avoid absorption by the photoactive sensitizer of the release layer composition. In some embodiments, the photoactive sensitizer is a photoacid generator ("PAG") catalyst (e.g., about 300 nm). For example, in some embodiments, the PAG absorbs in the near UV, so far UV radiative heating (e.g., from a high power LED source) is used to heat the polymer of the release layer. In some embodiments, the radiative heating wavelength is longer and / or shorter than the photoactive sensitizer (e.g., PAG) absorption wavelength. In some embodiments, the PAG has its maximum absorption at about 300 nm. As discussed herein, there are LEDs that can function as the actinic radiation source, making the optical system simpler.

[0066] In some embodiments, the radiation used to heat the substrate, release layer (e.g., a patterned release layer), and / or component may be injected parallel (i.e., from the side) into the element (e.g., film) rather than perpendicular (i.e., from the top or bottom major surface). In these embodiments, a waveguiding structure is fabricated on the donor plate surface adjacent to the polymer film. In some embodiments, light, e.g., IR light, may be coupled into this waveguiding structure at one edge of the donor plate and travel from here to the other side. In some embodiments, the wavelength of the light may be less than 0.05 / cm -1 An absorption coefficient of 0.01 can be sufficient for approximately 60% of the light to be absorbed at 20 cm (a typical size for donor plates in manufacturing applications). In some embodiments, this absorption may be slightly non-linear, with 5.0% being absorbed at the entrance edge over a distance of 1 cm, and 2.0% being absorbed at the exit edge over the final cm. However, in some embodiments, light may be injected from multiple edges (e.g., both edges), resulting in approximately uniform absorption across the plate (e.g., between 6.8% and 6.1%). In some embodiments, uniformity is achieved by reducing the absorption coefficient to less than 0.05 cm -1 In another embodiment, the absorption coefficient can be gradually increased across the donor plate during the fabrication process, resulting in a spatially uniform absorption profile.

[0067] FIG. 6 shows a top view of a system 600 including a donor plate assembly 602 having a proximal radiant heat source 604 and a distal radiant heat source 608 located at the side edges of the donor plate assembly 602. The proximal radiant heat source 604 is shown injecting proximal radiant heat 606 (e.g., IR light) and the distal radiant heat source 608 is shown injecting distal radiant heat 610 on each side of the donor plate assembly 602. In some embodiments, the radiant heat source(s) include an array of heat sources (e.g., an array of optical fibers, LEDs, and / or lasers). In some embodiments, the radiant heat source includes a lens (e.g., a cylindrical lens) that collimates, focuses, or diverges the light injected into the donor plate assembly. In some embodiments, the radiant heat source injects light into and / or onto the substrate (e.g., donor plate and / or light absorbing material), component, and / or release layer. In some embodiments, the radiant heat lines injected from the proximal and distal radiant heat sources form a substantially flat profile. In some embodiments, the radiant heating radiation injected from the proximal and distal radiant heating sources is configured to be absorbed quasi-linearly.

[0068] In some embodiments, the substrate (e.g., donor plate) includes a light absorbing material. In some embodiments, the light absorbing material is later incorporated onto and / or into the substrate. In some embodiments, a light absorbing layer is provided over the substrate and includes a light absorbing material and a host material. In some embodiments, the light absorbing material (e.g., a near-IR absorbing material) may be deposited onto or incorporated into a layer (e.g., glass). In some embodiments, the light absorbing material is deposited by vapor deposition. In some embodiments, vapor deposition includes evaporation, sputtering, ion beam assisted deposition, and combinations thereof. In some embodiments, the light absorbing material may have significant absorbance in the UV (e.g., at the wavelength used for actinic radiation). In some embodiments, the light absorbing material may have a UV absorbance greater than its IR absorbance. In some embodiments, a light absorbing material that has a UV absorbance greater than its IR absorbance should not significantly interfere with the application of actinic radiation to the release layer because the thickness is less than 10% of the width of the substrate (e.g., donor plate). -4 This is because the thickness is less than 1-10 μm. In some embodiments, materials suitable for cladding IR waveguides, well known in the field of optical fibers, have similar absorption properties for, for example, UV light and should not interfere with application. In some embodiments, depending on the refractive index of the IR absorbing layer, a fused silica donor plate may serve as one cladding layer.

[0069] 7 illustrates a side view of an assembly 700 including a donor plate 702, a first cladding layer 704 disposed on the donor plate 702, a light absorbing material 706 disposed on the first cladding layer 704, a second cladding layer 708 disposed on the light absorbing material 706, and a release layer 710 disposed on the second cladding layer 708, and a number of components 712 disposed on the release layer 710. In some embodiments, the configuration of the cladding layer and / or the properties of the light absorbing material enable the light absorbing material to act as a waveguide for light injected through the side edges of the donor plate. In some embodiments, the thickness of the light absorbing material is 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 1.2 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or 12 μm, or any range of values ​​therebetween. and is about, at most, or at most about such value. In some embodiments, the assembly does not include a first cladding layer. In some embodiments, the refractive index of the light absorbing material is greater than the donor plate material (e.g., silica). In some embodiments, the second cladding layer has a large evanescent wave transmission value. In some embodiments where cladding layer(s) are utilized, the light of the radiative heating is coupled or substantially coupled between the cladding layer or donor plate and the cladding layer through reflection (e.g., total internal reflection). In some embodiments where cladding layer(s) are utilized, the light of the radiative heating does not contact or does not substantially contact the release layer. In some embodiments where cladding layer(s) are utilized, the wavelength of the radiative heating may overlap or substantially overlap with the wavelength of the actinic radiation exposure.

[0070] 8 shows a side view of an assembly 800 including a donor plate 802, a first cladding layer 806a disposed over the donor plate 802, a graded light-absorbing material 804 disposed over the first cladding layer 806a, and a second cladding layer 806b disposed over the graded light-absorbing material 804. The graded light-absorbing material 804 is shown to decrease in thickness from the proximal to the distal end of the donor plate 802, while the first cladding layer is shown to increase in thickness from the proximal to the distal end of the donor plate 802. In some embodiments, the graded light-absorbing layer may help flatten the profile of light injected from the side edges of the donor plate. In some embodiments, the graded light-absorbing material may decrease in thickness from the proximal end to the middle portion of the donor plate and increase in thickness from the middle portion of the donor plate to the distal end. In some embodiments, the maximum thickness of the graded light-absorbing layer is about, or at least 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 15 μm, 20 μm, or 25 μm, or any value therebetween, In some embodiments, the minimum thickness of the graded light-absorbing layer is about, or at most 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 1.2 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, or 10 μm, or any value therebetween.

[0071] In some embodiments, the light absorbing material is an inorganic light absorbing material or an organic light absorbing material. In some embodiments, the inorganic light absorbing material includes Nd2O3, Sm2O3, VO3, CoO, NiO, and MnO2. In some embodiments, the host material includes SiO2, Al2O3, and other generally transparent dielectrics. In some embodiments, the organic light absorbing material is a polycarbonate compound and / or an aromatic compound. In some embodiments, the aromatic compound includes a quinoxaline compound (e.g., 4,6,7,9-tetra(thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline, and 2,2'-(6,6,12,12-tetraoctyl-6,12-dihydroindeno[1,2-b]fluorene-2,8-diyl)bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)). For example, in some embodiments, a polycarbonate membrane a few microns thick can achieve a thickness of 3000 cm -1 Approximately 10% (3.3μm, CH aromatic ring), 1800cm -1 The 45% absorbance at 1100-1300 (5.5 μm) and 85% absorbance at 1100-1300 (9.1-7.7 μm; the strongest being the OCO band) can be achieved. In some embodiments, a quantum cascade laser (QCL) can provide these wavelengths. Fused silica strongly absorbs >4.6 μm, so in some embodiments BaF can be used for the substrate since it is suitably transparent in both the IR and UV. In some embodiments, aromatic compounds (e.g., 4,6,7,9-tetra(thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline) have strong absorbance in the near IR (e.g., peak at 900 nm). In some embodiments, aromatic compounds absorb in the UV, so a photoactive photosensitizer (e.g., PAG) can be selected that absorbs in the valley between the UV peaks of the aromatic compound.

[0072] In these embodiments, IR laser diodes and / or LEDs may be advantageously used as radiative heating sources for the heating process. In some embodiments, wavelengths in the range of about 700 to about 900 nm may be utilized. In some embodiments, solid state emitters are commercially available with the ability to provide the required energy in pulses not exceeding a few microseconds in duration. In some embodiments, methods and equipment are utilized for coupling the emitted light into a fiber that can emit light into a donor plate waveguide. In some embodiments, other wavelengths and emitter technologies may also be used depending on the choice of absorber.

[0073] In some embodiments, a laser whose output is sufficiently coherent to remain collimated over a propagation distance of tens of centimeters may be used as the light source for radiative heating. In some embodiments, a waveguiding structure may not be required to confine the light to a thin layer. In some embodiments, the laser output is shaped by a suitable lens into a thin slab (e.g., on the order of a few micrometers thick and / or as wide as the donor plate) and directed into the bottom edge of the substrate (e.g., donor plate). In some embodiments, the laser light is directed adjacent to the release layer and / or into the release layer itself.

[0074] In some embodiments, the material to be heated by radiative heating may have sufficient radiative heating absorbance (e.g., IR absorbance) to be heated (e.g., at least to or near its decomposition temperature). In some embodiments, lasers that may be suitable include CO2, YAG (e.g., 355 nm), Nd:YAG (and related lasers, e.g., Nd:YLF) (e.g., about 1 μm and about 1.3 μm), diode lasers (e.g., about 800-900 nm), erbium-doped fiber (e.g., about 1.5 μm), quantum cascade lasers (QCLs) (e.g., multiple emission wavelengths above about 3 μm), CO2 lasers (e.g., about 10.6 μm), Alexandrite lasers (e.g., visible red to near-IR), Ti-sapphire lasers (e.g., visible red to near-IR), excimer lasers (e.g., XeF excimer; 351 nm), and others with fundamental power in the near-IR. In some embodiments, optical parametric amplifiers are utilized to generate the required wavelengths of light (e.g., mid-IR light). In some embodiments, multiple radiative heating sources (e.g., LEDs and / or lasers (e.g., of the same or different types and / or intensities)) may be used. In some embodiments, diode lasers may have the advantage of being fabricated by semiconductor processing (e.g., potentially lower cost than lasers involving crystals or gas discharges). In some embodiments, diode lasers may have variable pulse lengths in the sub-μs regime, and thus may span values ​​of τ in some embodiments. In some embodiments, diode lasers may be combined in arrays (e.g., similar to the “diode bars” used to pump YAG lasers) to provide the required intensity. In some embodiments, diode lasers may be operated in continuous wave (i.e., cw) or pulsed mode. In some embodiments, CO2 lasers may be utilized at high power, e.g., up to 8 kW or 20 kW cw power.In some embodiments, the CO2 laser emits at about 5.5 μm and / or 10.6 μm, with some nearby emission lines. In some embodiments, the high power CO2 laser has a power output of about 1-3 kW. In some embodiments, the CO2 laser may have a pulse width of about 10 μs or more. In some embodiments, the CO2 laser may have a duty cycle of the order of 50%.

[0075] In some embodiments, other wavelengths that match the low levels of absorbance of the material may be useful. It's fine.

[0076] Combination heating In some embodiments, heating of the release layer may include a combination of conductive and radiative heating. In some embodiments, conductive heating may be performed simultaneously with, before, and / or after radiative heating. In some embodiments, conductive heating may be performed for the same amount of time, a similar amount of time, or a different amount of time compared to radiative heating. For example, in some embodiments, a transparent conductive oxide layer may be used to heat the release layer to near its decomposition temperature (e.g., at a slow heating rate compared to the transfer reaction time), and a short pulse of radiative heating (e.g., IR light) is injected into the waveguiding structure to heat the release layer to its decomposition temperature. In some embodiments, the short pulse of radiative heating causes the transfer of the part.

[0077] Heating Form The heating process of the release layer (e.g., conductive heating, optical heating) may be carried out in various forms, including: 1) static forms, 2) real-time forms, and 3) mixed forms, as described herein.

[0078] 1)Stationary form In some embodiments, the release layer slowly (e.g., over a period of about, at most, or at most about 10 μs, 20 μs, 50 μs, 100 μs, 200 μs, 300 μs, 500 μs, 750 μs, 1 ms, 5 ms, 8 ms, 10 ms, 20 ms, 50 ms, 100 ms, 200 ms, 300 ms, 500 ms, 750 ms, or 1 s, or any range of values ​​therebetween) reaches a decomposition temperature T sd In some embodiments, the heating is performed in a static configuration by heating to a temperature (e.g., a photosensitizer decomposition temperature (e.g., a photoacid generator ("PAG") catalyst)). In some embodiments, the heating is performed prior to actinic radiation exposure, and then actinic radiation (e.g., to generate acid) is delivered in a pulse (e.g., quickly; 10 ns to 10 μs). In some embodiments, the heating is performed after actinic radiation exposure. In some embodiments, the heating is performed simultaneously with actinic radiation exposure. In some embodiments, the static configuration heating is performed for a period of about, at least, or at least about 10 μs, 20 μs, 50 μs, 100 μs, 200 μs, 300 μs, 500 μs, 750 μs, 1 ms, 5 ms, 8 ms, 10 ms, 20 ms, 50 ms, 100 ms, 200 ms, 300 ms, 500 ms, 750 ms, or 1 s, or any range of values ​​therebetween.

[0079] In some embodiments, the advantage of this approach is that the heating of the thin film is relatively simple (e.g., electrically simple), where the required power is delivered to reach the desired decomposition temperature while compensating for diffusion losses (e.g., to the SiO2 of the substrate). As an example, in some embodiments, the requirement for a 20 cm x 20 cm donor plate is on the order of magnitude of 1 kW. An additional advantage of this configuration is that the slow temperature rise of the heated system (e.g., donor plate, transparent resistive layer, release polymer, and transferable part, as well as any other layers that may be present) minimizes thermal stresses that may cause cracking or delamination. The rate of heating may vary over a wide range. In some embodiments, the system may be brought to a particular temperature (e.g., as required for sensitized decomposition) and held as long as necessary, or in some embodiments, the system may be heated for a period of seconds or milliseconds and then allowed to cool before the next transfer operation step (e.g., further heating and / or actinic radiation exposure).

[0080] In some embodiments, the static heating may be performed by conductive heating (e.g., electrical heating) and / or radiative heating. In some embodiments, the static heating may be performed by a light source (e.g., a laser) to deliver a rapid initiation light pulse. For example, in some embodiments, 3 mJ / cm at 10 μs 2 At an apparent dose of 300 W / cm 2may be required. In some embodiments, the required power may be provided by a conventional laser and / or LED. In some embodiments, the absorption maximum of the photosensitizer (e.g., PAG catalyst) is about 300 nm. Thus, in some embodiments, a deep UV light source (e.g., LED) may be used to emit up to 1 W for each component (e.g., about 100×100 μm chip). In some embodiments, a heating duty cycle of about, at most, or at most about 1%, 0.5%, 0.1%, 0.05%, 0.01%, 0.008%, 0.005%, 0.004%, 0.003%, 0.002%, 0.001%, 0.0009%, 0.0008%, 0.0005%, 0.0001%, 0.00005%, or 0.00001%, or any value therebetween, is utilized. For example, in some embodiments, the power may be utilized with a low duty cycle (e.g., 1% or less) to effectively remove heat. In other embodiments, the duty cycle may be 10 -3 %, or less. In some embodiments, the radiative heating source (e.g., a laser) is pulsed on for 10 μs and then off for 1-10 s. In some embodiments, the device is not intermittently cooled. In some embodiments, an all-diode-based illuminator is utilized. In other embodiments, a YAG or other large DUV laser is utilized.

[0081] 2) Real-time format In some embodiments, the release layer rapidly (e.g., in less than 10 μs) undergoes a T sdIn some embodiments, the heating is performed in real-time by pulse heating to 1000 K. In some embodiments, the heating is performed prior to actinic radiation exposure, and then actinic radiation (e.g., to generate acid) is delivered in a pulse (e.g., quickly; 10 ns to 10 μs). In some embodiments, the heating is performed after actinic radiation exposure. In some embodiments, the heating is performed simultaneously with actinic radiation exposure. In some embodiments, the heating in real time is performed over a period of about, at most, or at most about 5 ns, 10 ns, 20 ns, 30 ns, 40 ns, 50 ns, 60 ns, 70 ns, 80 ns, 90 ns, 100 ns, 200 ns, 300 ns, 400 ns, 500 ns, 600 ns, 700 ns, 800 ns, 900 ns, 1 μs, 2 μs, 3 μs, 4 μs, 5 μs, 6 μs, 7 μs, 8 μs, 9 μs, 10 μs, 20 μs, 50 μs, 100 μs, or 200 μs, or any range of values ​​therebetween.

[0082] For example, in some embodiments, heating (e.g., radiative heating) is performed while the film is at ambient temperature (e.g., 20° C.) and then at T sd In some embodiments, the heating is performed at a rate of nominally 15 mJ / cm for 10 μs. 2 , or 1.5kW / cm 2 For a 20x20 cm donor plate this is a total of 600 kW.

[0083] In some embodiments, a power supply may be used to generate short pulses of such high current and / or voltage. In some embodiments, voltages in the kV range and currents of hundreds of amperes (A) may be used to balance the requirements between current and voltage. Recognizing that the numerical targets themselves are merely approximations, Table 1 provides examples of voltages, currents, and resistances that may be used to achieve the same power output. Table 1 assumes a single transparent conductive oxide ("TCO") (20 x 20 cm) sheet with voltage applied along one edge. The R described is in Ω, but is also in Ω / □ for this geometry. R is on the order of 30 Ω / □ at 100 nm thickness (e.g., this is the value for La-doped SrSnO3). In some embodiments, the thickness should not be easily increased (due to optical absorbance) but may be decreased (= higher R). Therefore, in some embodiments, higher voltages and lower currents may be preferred. To generate such electrical pulses, There are several ways to achieve this, including built-in output MOSFETs, insulated gate bipolar transistors (IGBTs), output bipolar transistors, and "solidtrons" (these are called thyristors, a trade name from Excelitas Technologies, but are solid-state components). There are also high power switching devices that use vacuum tubes, but semiconductors are smaller, have a longer life, and are cheaper. [Table 1]

[0084] In some embodiments, the heating source (e.g., TCO) may be divided into strips to reduce the current requirements of each supply. When a very narrow gap (e.g., 0.5 μm) is lithographically fabricated between two strips of the heating source (e.g., TCO), all areas of the polymer surface will still be within 0.25 μm of the heating element. Such a structure does not substantially deviate from the uniform heating structure. In some embodiments, even narrower gaps may be utilized, since there should be a minimum potential difference between the strips. Variations in the time characteristics of the driving electronics may result in very small transient differences, not enough to cause a short circuit between the two strips. For example, when a 20 cm square sheet is divided into 10 strips, the power required for each is 1 / 10 of that given in Table 1, with a corresponding reduction in the product of voltage and current. So 60,000 W may be achievable with 4000 V, 15 A, and 267 Ω (with a TCO sheet resistance of 27 Ω / □). 30 Ω / □ is a "safe" number for achievable TCO properties, but lower values ​​may be used in some embodiments depending on the UV power available for photochemistry and the required throughput of the process in question.

[0085] In some embodiments, the disclosed processes may require rapid changes in both voltage and current, so capacitance and inductance must be within acceptable limits. For capacitance, the basic charging equation is involved: V=Vo[1-e-(t / RC). The capacitance of a parallel plate geometry is C=εA / d, where ε=ε0ε r is the dielectric constant, approximately 4 × 8.85 × 10 -12F / m. In some embodiments, when the current return path is on the opposite side of the donor plate from the TCO, the plate thickness d is about 1 mm and C is about 1.5 nF. The time constant to charge the sheet to 1 kV is now t=-RC{ln[1-(V / V0)]}≈4.6RC (charge to 99% of the desired voltage)≈5 ns. In some embodiments, the return path is a wire rather than a conductive surface, and no easy calculations are possible. Bioelectronic-based estimates (e.g., the capacitance of a person carrying a conductive sheet) are at least an order of magnitude lower, leading to correspondingly faster rise times.

[0086] Accounting for parasitic inductances also leads to small (e.g., sub-ns) time constants. Although these numbers and formulas are approximations, they indicate that these effects will not prevent the system from reaching the desired electrical state in the required time.

[0087] In some embodiments, the output components (e.g., solid-state) referenced above may be small enough to be integrated into small-scale units. In some embodiments, the output components may be part of the exposure tool. In some embodiments, the substrate (e.g., donor plate) may contact a copper or gold layer covering a conductive heating source (e.g., TCO) at its edge or in narrow strips on its top and / or bottom major surfaces, as described above. Therefore, in some embodiments, it may not be necessary to remove the substrate (e.g., donor plate) from the exposure tool to perform the thermal transfer process.

[0088] In some embodiments, in a real-time fashion, the amount of heat introduced to the substrate (e.g., donor plate) can vary depending on the thickness of the heated film as well as the time the heat is turned on (e.g., about 10 -5The thermal conductivity of the conductive heat source (e.g., TCO) layer may be limited by the short time between heating (e.g., duty cycle). In some embodiments, the conductive heat source (e.g., TCO) layer is protected by a thin layer (e.g., 100-500 nm) of hard insulator. In some embodiments, the hard insulator comprises a material such as, for example, silicon oxide, silicon nitride, aluminum oxide, boron nitride, diamond, etc.

[0089] 3) Mixed form In some embodiments, the release layer is heated by a combination of static and real-time heating. In some embodiments, the real-time heating is performed before, after, or simultaneously with the static heating. For example, in some embodiments, T sd A slow, static pre-heating of the release layer to a temperature near but below this temperature is achieved, and then a subsequent real-time pulse of heat (e.g., conductive heating (e.g., electrical energy) and / or radiative heating) (e.g., less than those calculated in Table 1) is applied to heat the release layer to at least T sd In some embodiments, a subsequent heating step initiates the decomposition reaction of the release layer.

[0090] In some embodiments, a mixed mode heating process may be advantageous in that it may help control the timing of the steam expansion and may have system mechanic advantages (e.g., reducing the I and V requirements of the pulsed power supply, etc.). In some embodiments, it may be possible to achieve at most T sd Any set of parameters for heating over time that does not exceed but exceed the temperature may be used. In some embodiments, the temperature may also be varied (by varying the heat input) during the reaction.

[0091] Although certain specific embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the present disclosure. Indeed, the novel methods and systems described herein may be embodied in a wide variety of other forms. Furthermore, various omissions, substitutions, and modifications of the systems and methods described herein may be made without departing from the spirit of the present disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as are within the scope and spirit of the present disclosure.

[0092] It should be understood that features, materials, properties, or groups described in connection with a particular aspect, embodiment, or example may be applicable to any other aspect, embodiment, or example described in this section or anywhere in the specification, unless inconsistent therewith. All of the features disclosed in this specification (including any accompanying claims, abstract, and figures), and / or all of the steps of any method or process so disclosed, are intended to be understood as including, but not limited to, all of the features, materials, properties, or groups described in connection with a particular aspect, embodiment, or example, unless inconsistent therewith, all of the features, materials, properties, or groups described in connection with a particular aspect, embodiment, or example may be applicable to any other aspect, embodiment, or example described in this section or anywhere in the specification, unless otherwise stated therein. All of the features, materials, properties, or groups disclosed in this specification (including any accompanying claims, abstract, and figures), and / or all of the steps of any method or process so disclosed, are intended to be understood as including, but not limited to, all of the features, materials, properties, or groups disclosed in this specification (including any accompanying claims, abstract, and figures), except as though at least some of such features and / or steps were mutually exclusive. The invention may be combined in any combination, except in combinations which are otherwise incompatible. Protection is not limited to the details of any of the above embodiments. Protection extends to any novel one or any novel combination of features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one or any novel combination of steps of any method or process so disclosed.

[0093] Moreover, certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a particular combination, one or more features from a claimed combination can in some cases be deleted from the combination, and the combination may be claimed as a subcombination or various subcombinations.

[0094] Furthermore, although operations may be shown in the figures or described herein in a particular order, such operations need not be performed in that particular order or sequence shown, or all of the operations need not be performed, to achieve desired results. Other operations not shown or described may be incorporated into the example methods and processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between the operations described. Furthermore, operations may be rearranged or reordered in other implementations. Those skilled in the art will recognize that in some embodiments, the actual steps employed in the illustrated and / or disclosed processes may differ from those shown in the figures. Depending on the embodiment, certain of the above steps may be removed and others may be added. Furthermore, the features and characteristics of the specific embodiments disclosed above may be combined in different ways to form further embodiments, all of which are within the scope of the present disclosure. Also, the separation of various system components in the above implementations should not be understood as requiring such separation in all implementations, and it should be understood that the components and systems described may generally be integrated together in a single product or packaged in multiple products. For example, any of the components for the energy storage system described herein may be applied separately or integrated together (e.g., packaged together or attached together) to form an energy storage system.

[0095] For purposes of this disclosure, certain aspects, advantages, and novel features have been described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, one skilled in the art will recognize that the disclosure may be embodied or performed in a way that achieves one advantage or advantages taught herein without necessarily achieving other advantages that may be taught or suggested herein.

[0096] Conditional language, such as "can," "could," "might," or "may," is generally intended to convey that a particular embodiment includes certain features, elements, and / or steps but not other embodiments, unless specifically stated otherwise or understood otherwise within the context in which it is used. As such, such conditional language may not necessarily convey that features, elements, and / or steps are required in any way for one or more embodiments, or that one or more embodiments may include those features, elements, and / or steps in any particular embodiment or may be modified in any way to suit the particular embodiment. It is generally not intended to imply that the invention necessarily includes logic for determining, with or without user input or indication, whether a program should be implemented in a program.

[0097] Conjunctive language, e.g., the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is generally understood by the context in which it is used to convey that an item, term, etc. may be either X, Y, or Z. As such, such conjunctive language is generally not intended to imply that a particular embodiment requires the presence of at least one of X, at least one of Y, and at least one of Z.

[0098] As used herein, words of degree, such as the terms "approximately," "about," "generally," and "substantially," when used herein, represent a value, amount, or characteristic that is close to a stated value, amount, or characteristic that still performs a desired function or achieves a desired result.

[0099] The scope of the disclosure is not intended to be limited by the specific disclosure of embodiments in this section or anywhere else herein, but may be defined by the claims presented or hereafter presented in this section or anywhere else herein, which claim language should be interpreted broadly based on the language used in the claims and not limited to the examples described herein or during prosecution of this application, which examples should be interpreted as non-exclusive.

[0100] Although certain specific embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the present disclosure. Indeed, the novel methods and systems described herein may be embodied in a wide variety of other forms. Furthermore, various omissions, substitutions, and modifications in the systems and methods described herein may be made without departing from the spirit of the present disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as are within the scope and spirit of the present disclosure. Thus, the scope of the present invention is defined solely by the appended claims.

Claims

1. 1. A process for transferring a part, comprising: providing an assembly including a substrate, a release layer, and a component, the release layer being disposed on the substrate and the component being adhered to the release layer; heating the release layer from a heat source to at least a decomposition temperature, the heating being selected from the group consisting of conductive heating, radiative heating, and combinations thereof; and exposing the release layer to actinic wavelength light from an actinic radiation source; Including, the heating and exposing step decomposes the release layer and transfers the component from the substrate to a target substrate; the heat source and the actinic radiation source are different sources; and A process wherein at least one of said heating and exposing steps is carried out within a pulse period.

2. 10. The process of claim 1, wherein the heating comprises radiative heating with light at radiative wavelengths, the overlap between the radiative and actinic wavelengths being up to 20%.

3. 3. The process of claim 2, wherein the radiative heating is at a radiation wavelength selected from the group consisting of UV wavelengths, visible wavelengths, IR wavelengths, microwave wavelengths, and combinations thereof.

4. 3. The process of claim 2, wherein the radiative heating is at a radiation wavelength of 300 nm to 100,000 nm.

5. The process of claim 2 , wherein the substrate comprises a donor plate and a light-absorbing material.

6. The light absorbing material is Nd ２ O ３ , Sm ２ O ３ , V ２ O ３ , CoO, NiO, MnO ２ 6. The process of claim 5, wherein the compound is selected from the group consisting of a polycarbonate compound, an aromatic compound, and combinations thereof.

7. The process of claim 2 wherein the radiant heating is applied from a side edge of the assembly.

8. The process of any one of claims 1 to 7, wherein the decomposition temperature is from 100°C to 350°C.

9. The process of any one of claims 1 to 7, further comprising heating the release layer to a first temperature before heating the release layer to the decomposition temperature.

10. 10. The process of claim 9, wherein the first temperature is from 100°C to 350°C.

11. The process of any one of claims 1 to 7, wherein the pulse duration is between 10 ns and 10 μs.

12. The process of any one of claims 1 to 7, wherein the heating step is carried out before the exposing step.

13. The process of any one of claims 1 to 7, wherein the heating step is carried out after the exposing step.

14. The process of any one of claims 1 to 7, wherein the heating step is carried out simultaneously with the exposing step.

15. The process of any one of claims 1 to 7, wherein the actinic wavelengths of light are selected from the group consisting of UV wavelengths, visible wavelengths, and combinations thereof.

16. The process of any one of claims 1 to 7, wherein the actinic wavelength of the light is from 200 nm to 400 nm.

17. The actinic radiation source has a power of 10 mJ / cm ２ ~200 mJ / cm ２ The process of any one of claims 1 to 7, comprising a power density of

18. The process of any one of claims 1 to 7, wherein the heat is applied directly to the release layer.

19. The process of any one of claims 1 to 7, wherein the heat is applied directly to the part, which heats the release layer to the decomposition temperature.

20. The process of any one of claims 1 to 7, wherein the heat is applied directly to the substrate, which heats the release layer to the decomposition temperature.

21. The process of any one of claims 1 to 7, wherein the assembly further comprises a conductive heating source.

22. 22. The process of claim 21, wherein the conductive heat source comprises a transparent conductive heat source.

23. The transparent conductive heat source is made of ITO, β-Ga ２ O ３ , gold, silver, La-doped SrSnO ３ 23. The process of claim 22, wherein the hydroxyl group is selected from the group consisting of:

24. 1. A process for transferring a part, comprising: An assembly is provided that includes a substrate, a release layer, and a component, the release layer comprising: providing an assembly disposed on a substrate, the component being adhered to the release layer; heating the release layer from a heat source to at least a decomposition temperature, the heating being selected from the group consisting of conductive heating, radiative heating, and combinations thereof, and the decomposition temperature being between 180°C and 220°C; and exposing the release layer to actinic wavelength light from an actinic radiation source, wherein the actinic wavelength of the light is between 230 nm and 360 nm; Including, the heating and exposing step decomposes the release layer and transfers the component from the substrate to a target substrate; the heat source and the actinic radiation source are different sources; and The process wherein at least one of the heating and exposing steps is performed within a pulse duration of 10 ns to 10 μs.

25. 1. An assembly for transferring a part, comprising: substrate; a plurality of heating sources disposed above the substrate; and a release layer disposed on the plurality of heating sources; Including the assembly.

26. 26. The assembly of claim 25, further comprising a nanoporous material disposed between the substrate and the plurality of heating sources.

27. 1. An assembly for transferring a part, comprising: substrate; a light absorbing layer disposed on the substrate; a first cladding layer disposed on the light absorbing layer; and a release layer disposed on the first clad layer; Including the assembly.

28. 30. The assembly of claim 27, further comprising a second cladding layer disposed between the substrate and the light-absorbing layer.

29. 29. The assembly of claim 27 or 28, wherein the light absorbing layer is a graded light absorbing layer.

30. The process described in any one of claims 1 to 7, wherein the release layer comprises a photosensitized decomposition compound selected from at least one of a polymer and an oligomer, and the photosensitized decomposition compound is configured to decompose when heated and exposed to light of an actinic wavelength.

31. The process of claim 30, wherein the thermal decomposition temperature of the photosensitized decomposition compound is reduced to at most its decomposition temperature when exposed to light of an actinic wavelength.

32. The process of claim 30, wherein the photosensitized decomposition compound comprises a linking portion and a core unit comprising a tetralin core, a cyclohexane core, copolymers thereof, and combinations thereof.

33. The process of claims 1 to 7, wherein the release layer further comprises a photoactivatable photosensitive material.

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