Biodegradable polymers in microsolid printing processes

Abstract

The present disclosure relates to integrating microsemiconductor devices into a system substrate using a resolvable polymer. In at least one implementation, a method includes: metalizing a substrate by mixing a metal powder in a resolvable polymer under light or heat; patterning using a printing process; and resolving the resolvable polymer to sinter the metal powder.

Description

Priority requirements

[0001] This application claims priority to U.S. Provisional Application No. 63 / 575,512, filed April 5, 2024, entitled “DECOMPOSABLE POLYMER IN MICROSOLIDPRINTING PROCESS,” the entire contents of which are incorporated herein by reference. Summary of the Invention

[0002] This disclosure relates to a method for integrating microdevices into a system substrate using a biodegradable polymer in a MicroSolid printing process. In at least one embodiment, the method includes: metallizing the substrate by mixing metal powder into the biodegradable polymer with light or temperature, patterning it using a printing process, and decomposing the polymer at a high temperature to sinter the metal powder. Attached Figure Description

[0003] The materials described herein are illustrated in the accompanying drawings by way of embodiment rather than limitation. For simplicity and clarity, the elements illustrated in the drawings are not necessarily drawn to scale. For embodiments, for clarity, the dimensions of some elements may be enlarged relative to others. Furthermore, for clarity of discussion, various physical features may be represented in their simplified "ideal" forms and geometries; however, it should still be understood that actual implementations may approximate the illustrated ideal forms. For embodiments, smooth surfaces and square intersections may be drawn while neglecting the finite roughness, fillets, and imperfect angular intersection characteristics of structures formed by nanofabrication techniques. Additionally, reference numerals are repeated in the drawings where deemed appropriate to indicate corresponding or similar elements.

[0004] The foregoing and other advantages of this disclosure will become apparent from reading the following detailed description and referring to the accompanying drawings.

[0005] Figure 1A This is an illustration of a structure in at least one embodiment, wherein a microdevice with pads is positioned above a biodegradable material for bonding.

[0006] Figure 1B In at least one implementation scheme Figure 1A The diagram illustrates the structure in which microdevices are bonded to the top of pads within a biodegradable material.

[0007] Figure 1C In at least one implementation scheme Figure 1C The diagram illustrates the structure in which microdevices undergo bonding processes under pressure and temperature conditions that can decompose the decomposable material and couple the microdevices to the system substrate.

[0008] Figure 1D This is a diagram of a structure in which a microdevice with pads is electrically coupled to conductive bumps as one embodiment of direct bonding.

[0009] Figure 1E In at least one implementation, this occurs after the release layer has been removed. Figure 1D A diagram of the structure in the image.

[0010] Figure 1F This is an illustration of a structure in at least one embodiment, wherein a microdevice with pads is electrically coupled to bonding pads surrounded by a multilayer stack of decomposable material.

[0011] Figure 1G This is in at least one embodiment after a process that decomposes a multilayer stack of decomposable materials. Figure 1F A diagram of the structure in the image.

[0012] Figure 1H Examples are given in at least one embodiment. Figure 1F The reinforced cross section is taken along line A-A' of the structure.

[0013] Figure 1I Examples are given in at least one embodiment. Figure 1F The reinforced cross section is taken along line A-A' of the structure.

[0014] Figure 1J This is a diagram illustrating a structure comprising a dielectric material between a biodegradable material and a conductive pad in at least one embodiment.

[0015] Figure 2 A flowchart illustrating a method for transferring a microdevice from a substrate in at least one embodiment is provided.

[0016] Figure 3 An example is illustrated of a box structure having a thermally degradable polymer (TDP) as a release layer in at least one embodiment.

[0017] Figure 4 An example is given after the process of decomposing and releasing the layer. Figure 2 The box structure in the middle.

[0018] Figure 5 An example is illustrated of a microdevice integrated in a cell using LGT material for cell development in at least one embodiment.

[0019] Figure 6 An example is illustrated of a microdevice integrated in a cell using LGT material for cell development in at least one embodiment.

[0020] Figure 7Examples are given in at least one embodiment. Figure 5 The cross-section of the structure in which the decomposable layers comprise a double-layer stack.

[0021] Figure 8 Examples are given in at least one embodiment. Figure 6 The cross-section of the structure in which the decomposable layers comprise a double-layer stack.

[0022] While this disclosure is open to various modifications and alternative forms, specific embodiments or particular implementations have been shown in the accompanying drawings by way of embodiments and will be described in detail herein. However, it should be understood that this disclosure is not intended to be limited to the specific forms disclosed. Rather, this disclosure is intended to cover all modifications, equivalent substitutions, and alternatives that fall within the substance and scope of the disclosure as defined by the appended claims. Detailed Implementation

[0023] At least one embodiment describes a method for integrating microsemiconductor devices into a system substrate using a microSolid printing process. Integrating microsemiconductor devices into a system substrate provides opportunities to create different functions and applications, such as microLED displays and microsensors. In at least one embodiment, the microSolid printing process involves developing and fabricating microdevices on a virgin substrate and selectively or integrally moving them from the virgin substrate into a system substrate.

[0024] In at least one embodiment, metallization in the form of pads is required to achieve control before or after transferring the microdevices into the system substrate. In at least one embodiment, electrically connecting the microdevices to the system substrate may require a bonding material with electrical connectivity. In at least one embodiment, a housing substrate is implemented to hold the microdevices and selectively release them into the system substrate via pads. This paper discusses the use of thermally degradable polymers to construct various components associated with integrating microdevices into the system substrate. In at least one embodiment, the thermally degradable polymer transforms into vapor or gas at a nominal temperature.

[0025] In at least one embodiment, metallization on a large substrate may limit the potential for printed production of optoelectronic array devices, such as displays and sensors. In at least one embodiment, metallization is performed in a large-area high-vacuum chamber, followed by patterning. In at least one embodiment, metal powder can be mixed with a polymer that can decompose under the influence of light or temperature. Printing processes such as inkjet or spray printing can develop the mixture of polymer and metal powder into a desired pattern. After the desired pattern is formed, the polymer can decompose at a high temperature, and the metal powder can be sintered. In at least one embodiment, two or more metals can be used to achieve low-temperature sintering and high conductivity. In at least one embodiment, silver and indium can be added to a composable polymer solution.

[0026] In at least one embodiment, the biodegradable polymer can be mixed with conductive nanoparticles to facilitate electrical and mechanical bonding between the microdevice and the system substrate. In at least one embodiment, the material can be formed on the receiving substrate in the form of bumps. In at least one embodiment, the microdevice can be positioned and bonded to the bumps at a temperature equal to or higher than the glass transition temperature of the polymer used. In at least one embodiment, after transferring the microdevice, pressure and / or temperature can be applied to decompose the polymer, thereby leaving the conductive nanoparticles between the device and the system substrate to form electrical and mechanical connections. In at least one embodiment, the nanoparticles can be metals (such as silver, gold, copper) or other conductive materials. In at least one embodiment, two or more different nanoparticle types can be used to improve adhesion strength and conductivity, thereby ensuring reliable interconnection between the microdevice and the substrate.

[0027] In at least one embodiment, a polymer material covers the surface of the system substrate, and the microdevice can be bonded to the system substrate at a temperature above the glass transition temperature of the polymer. In at least one embodiment, the microdevice includes pads.

[0028] In at least one embodiment, after alignment, the system undergoes a controlled thermal or pressure process to decompose the polymer material beneath the microdevice pads. This process ensures direct electrical and mechanical contact between the microdevice and the system substrate, leaving only conductive nanoparticles or bumps to establish permanent connections.

[0029] In at least one embodiment, a solution can be used to remove any remaining polymer and particles embedded in the polymer from the surface of the substrate. In at least one embodiment, the polymer material can be deposited on top of the conductive bumps. In at least one such embodiment, once the polymer material decomposes, the microdevice can be bonded to conductive pads on the system substrate.

[0030] Figure 1AThis is an illustration of structure 100A. In at least one embodiment, structure 100A includes a microdevice 108 positioned above system substrate 120. In at least one embodiment, structure 100A also includes a biodegradable material 124 and pads 122 within the biodegradable material 124. In at least one embodiment, structure 100A is an embodiment using biodegradable material for bonding. In at least one embodiment, biodegradable material 124 is coated on system substrate 120. Selective surface coating for microdevice bonding:

[0031] In at least one embodiment, a biodegradable material 124 is uniformly coated on the entire surface of the system substrate 120 prior to microdevice bonding. In at least one such embodiment, the biodegradable material 124 surrounds pads 122. In at least one embodiment, pads 122 extend through the biodegradable material 124 and contact the system substrate 120. In at least one embodiment, pads 122 may be conductive or non-conductive. In at least one embodiment, microdevice 108 includes one or more pads, such as pads 112 electrically coupled to microdevice 108. In at least one example, pads 112 comprise a conductive material.

[0032] In at least one embodiment, the microdevice 108 includes a pair of pads, such as pads 112. In at least one embodiment, the system substrate 120 includes a plurality of pads 122. In at least one such embodiment, the layout of the pads in the microdevice 108 is designed to match the pads 122 on the system substrate 120.

[0033] In at least one embodiment, the biodegradable material 124 includes one of the following: poly(methyl methacrylate) (PMMA), polystyrene (PS), polypropylene carbonate (PPC), or some photoresist that can decompose under certain conditions.

[0034] In at least one embodiment, the pad 122 includes one of the following: indium, gold, copper, tin, tungsten, carbon nanotubes, silver, etc.

[0035] Figure 1B This is a diagram of structure 100B. In at least one embodiment, structure 100B is constructed after a process of aligning the pads 112 of the microdevice 108 with the top surface 122A of the pads 122 within the decomposable material 124. Figure 1A The diagram illustrates structure 100A. In at least one embodiment, pad 122 may be a bonding pad. In at least one embodiment, microdevice 108 is positioned on decomposable material 124 and is bonded using a temperature exceeding the glass transition temperature of decomposable material 124.

[0036] In at least one embodiment, a plurality of microdevices 108 are aligned with a system substrate 120. In an exemplary embodiment, the pads 112 of a single microdevice 108 are shown aligned and bonded to pads 122. In at least one embodiment, the top surface 122A of each pad 122 may have the same or substantially the same cross-sectional shape and size as the lower surface 112A of the pad 112. In at least one embodiment, the top surface 122A of each pad 122 may have a cross-section larger than that of the lower surface 112A of the pad 112.

[0037] In at least one embodiment, after alignment, the microdevice 108 is bonded to pads 122 within the biodegradable material 124. In at least one embodiment, a plurality of microdevices (such as microdevice 108) are aligned and bonded to a plurality of pads 122. In at least one embodiment, after bonding, a selected set of microdevices 108 is left on the system substrate 120. In at least one embodiment, a polymer material within the biodegradable material 124 covers the surface of the system substrate 120 (not visible in the figure), and one or more microdevices 108 can be bonded to the system substrate 120 at a temperature higher than the glass transition temperature of the polymer material within the biodegradable material 124. Microdevice bonding

[0038] A biodegradable material 124 is coated onto the system substrate 120, thereby covering or surrounding the bonding pads 122. The microdevice 108 is then placed on top of the biodegradable material layer, thereby ensuring proper alignment with the bonding pads. Figure 1C This is a diagram of structure 100C. In at least one embodiment, structure 100C is constructed after the process of joining and releasing the decomposable material 124. Figure 1B An illustration of structure 100B. In at least one embodiment, structure 100B undergoes a process at pressures and temperatures capable of decomposing the decomposable material 124, and in at least one embodiment, a microdevice 108 is coupled to a system substrate 120. In at least one example, the microdevice 108 can be subjected to pressures ranging from 0.1 N / mm² to 1000 N / mm² and temperatures ranging from 20°C to 500°C to decompose the decomposable material 124 and couple the microdevice 108 to the system substrate 120, as shown.

[0039] In at least one embodiment, the biodegradable polymer can be mixed with conductive nanoparticles within pad 112. In at least one embodiment, pressure or temperature can be applied to decompose the polymer within the biodegradable material 124, thereby leaving conductive particles between the microdevice 108 and the pad 122 on the system substrate 120. In at least one embodiment, the microdevice 108 can be bonded to the system substrate 120 at a temperature equal to or higher than the glass transition temperature of the polymer within the biodegradable material 124. In at least one embodiment, the nanoparticles can be a metal or other conductive material. In at least one embodiment, two or more materials can facilitate mechanical bonding of the microdevice 108 to the pad 122 in the system substrate 120.

[0040] In at least one embodiment, after the microdevice is transferred, the polymer material within the decomposable material 124 beneath the pad 112 can be decomposed using a high-temperature and / or pressure process. In at least one embodiment, the pad 122 is a conductive pad. In at least one further such embodiment, once the polymer material has decomposed, the microdevice 108 can be bonded to the conductive pad 122 on the system substrate 120, thereby allowing direct conductivity between the pad 112 (or the microdevice 108) and the pad 122 on the system substrate 120.

[0041] In at least one embodiment, to ensure optimal performance and prevent contamination, a solvent or etching solution can be used to remove any remaining polymer, and this solvent or etching solution can be applied to remove any residual polymer and nanoparticles still embedded on the surface 120A of the system substrate 120 after the decomposition process. Residue removal can provide a clean and high-quality electrical interface between the microdevice 108 and the system substrate 120. Conductive bump integration for direct bonding

[0042] In at least one embodiment, conductive bumps may be implemented for direct bonding. Figure 1D This is an illustration of structure 100D. In at least one embodiment, a biodegradable material 124 is selectively deposited on top of conductive bumps 130 pre-formed on the system substrate 120. In at least one embodiment, the bumps may be made of soldering material, metal nanoparticles, or other conductive materials. In at least one embodiment, microdevices 108 are placed on the conductive bumps 130 and are bonded using a temperature-controlled process.

[0043] Figure 1EThis is an illustration of structure 100E. In at least one embodiment, after the decomposable material 124 decomposes, the microdevice 108 forms direct electrical contact with the conductive bump 130, thereby providing a stable and reliable interconnect, as shown. The use of bumps can provide enhanced conductivity and improved mechanical stability, making it suitable for high-performance microdevice applications such as microLED displays, semiconductor integration, and microsensor arrays. Hybrid bonding with multilayer nanoparticle interfaces

[0044] In at least one embodiment, a conductive hybrid bonding with a multilayer nanoparticle interface can be utilized. Figure 1F This is an illustration of a microdevice 108 positioned above a multilayer structure 140 in at least one embodiment. In at least one embodiment, the multilayer structure 140 may be implemented to improve the mechanical stability of the bonded microdevice 108 and enhance its electrical performance.

[0045] In at least one embodiment, the multilayer structure 140 includes a first layer of biodegradable polymer 142 mixed with large conductive particles (e.g., silver or copper microsheets) applied to enhance mechanical anchoring, and a second layer of biodegradable polymer 146 having smaller conductive nanoparticles (e.g., silver nanowires or carbon nanotubes) deposited on top of the first layer of biodegradable polymer 142 to improve conductivity.

[0046] Figure 1G This is a diagram of structure 100H. In at least one embodiment, structure 100F illustrates the process after releasing the multilayer structure 140. Figure 1F Structure 100F in the multilayer structure 140. In at least one embodiment, after the release or decomposition of the first layer of biodegradable polymer 142 and the second layer of biodegradable polymer 146 in the multilayer structure 140, the microdevice 108 is bonded to the pad 122. (See again...) Figures 1F to 1G In at least one embodiment, after the first layer of the layer and the biodegradable polymer 142 has decomposed, the multilayer structure 140 provides a robust conductive path, thereby ensuring high electrical and mechanical properties. In at least one embodiment, the multilayer structure 140 can be used in applications requiring ultra-low resistance electrical interconnects, such as high-speed microprocessors and optoelectronic devices.

[0047] In at least one embodiment, structure 100G includes a conductive structure comprising two types of particles formed by the combination of decomposed polymers 142 and 146. In at least one embodiment, the lower layer comprises large conductive nanoparticles 144, and the upper layer comprises smaller conductive nanoparticles 148 or more nanosheets. In at least one embodiment, after the decomposition of the decomposed polymers 146 and 142, the rectangular layer is removed, and the nanoparticles and nanosheets can be meshed, as shown. In at least one embodiment, the stack of conductive nanoparticles 144 and 148 can be meshed or fused together. In at least one embodiment, the stack of conductive nanoparticles 144 and 148 can have irregular boundaries. Hereinafter, "irregular" can refer to serrated or uneven.

[0048] In at least one implementation scheme, Figure 1H and Figure 1I The example shown is through Figure 1G A cross-sectional view of structure 100G is shown. In at least one embodiment, the conductive nanoparticle 144 is a large nanoparticle, and the conductive nanoparticle 148 may be a nanosheet with a smaller size compared to the conductive nanoparticle 144.

[0049] Figure 1I Along the structure 100I in at least one embodiment Figure 1G The cross-section of line AA is shown. In at least one embodiment, the conductive nanoparticle 144 is a large nanoparticle, and the conductive nanoparticle 148 may be a nanowire with a smaller size compared to the conductive nanoparticle 144.

[0050] In at least one embodiment, although two different nanoparticles are illustrated, multilayer stacking can include more than two different nanoparticles. In at least one embodiment, conductive nanoparticles 144 and conductive nanoparticles 148 comprise the same type of nanoparticles. In at least one embodiment, through layer design, the same microdevice 108 can include two different combinations of nanoparticles over two different pads 122.

[0051] In at least one embodiment, a laser or targeted heating method can be implemented to achieve localized polymer decomposition. In at least one such embodiment, a localized heating method (such as laser-assisted decomposition or infrared heating) can be used to decompose the material 124 ( Figure 1B and Figure 1E Selective decomposition of the bonding and decomposition processes. In at least one embodiment, laser-assisted decomposition or infrared heating can allow for precise control of the bonding and decomposition processes, thereby minimizing the thermal exposure of sensitive microdevices.

[0052] In at least one embodiment, laser-based decomposition can also enable selective reprocessing of specific microdevices without affecting the entire system or microdevice, thereby providing increased flexibility in manufacturing and repair processes.

[0053] Refer again Figure 1A In at least one implementation, dielectric or insulating pads may be implemented to enhance alignment and positioning. Figure 1J This is an illustration of a structure 100J including a dielectric 150 between a biodegradable material 124 and a conductive pad 122 in at least one embodiment. In at least one embodiment, the dielectric 150 may have the form of a spacer surrounding the pad 122. In at least one embodiment, the dielectric may include one of silicon and one or more of oxygen, nitrogen, or carbon. In at least one embodiment, an insulating layer or dielectric layer is added between the biodegradable material 124 and the conductive pad 122 to enhance microdevice positioning and prevent short circuits during the bonding process. In at least one embodiment, the dielectric layer or insulating layer may laterally surround the pad 122 in the form of a spacer to ensure that only the intended conductive areas (such as the upper surface) are exposed after the biodegradable material 124 has decomposed, thereby enabling precise electrical connections. This technique is particularly beneficial for high-density microdevice integration, where precise alignment and controlled interconnect formation are crucial.

[0054] Refer again Figure 1A and Figure 1F Conductive nanoparticles can enhance the electrical connection between the microdevice 108 and the system substrate 120, thereby reducing resistance and improving reliability. In at least one embodiment, Figures 1A to 1I The methods described also offer scalability and flexibility, with the different methods described being compatible with a range of materials and device architectures, including microLEDs, MEMS, and advanced semiconductor devices. In at least one embodiment, laser-assisted or localized thermal decomposition allows for precise control, minimization of damage to surrounding components, selective transfer, and the ability to perform rework processes, such as re-transferring one or more microdevices with minimal impact on any remaining microdevices that may have already been transferred with high fidelity.

[0055] In at least one implementation, the above method can also achieve high-density integration, such as fine-pitch microdevice bonding, which may be useful for applications such as AR / VR microdisplays and compact sensor arrays.

[0056] In at least one embodiment, the above method is also compatible with multi-material integration processes. For implementations, the above method can support hybrid bonding of different microdevices, such as integrating microLEDs with silicon photonic devices or MEMS devices. In at least one embodiment, by combining one or more of the above methods and processing techniques, the MicroSolid printing process using biodegradable polymers or biodegradable materials 124 can be further optimized for next-generation microdevice integration, thereby providing enhanced performance, reliability, and manufacturing efficiency. Advantages of extended process

[0057] Improved electrical performance: Conductive nanoparticles enhance the electrical connection between the microdevice and the system substrate, thereby reducing resistance and improving reliability.

[0058] Scalability and flexibility: This approach is compatible with a variety of materials and device architectures, including microLEDs, MEMS, and advanced semiconductor devices.

[0059] Selective transfer and reworkability: Laser-assisted or localized thermal decomposition allows for precise control, thereby minimizing damage to surrounding components.

[0060] High-density integration: enabling fine-pitch microdevice bonding, which is crucial for applications such as AR / VR microdisplays and compact sensor arrays.

[0061] Compatibility with multi-material integration: This method supports hybrid bonding of different microdevices, such as integrating microLEDs with silicon photonic devices or MEMS devices.

[0062] By combining these advanced implementation schemes and processing technologies, the MicroSolid printing process using biodegradable polymers can be further optimized for next-generation microdevice integration, thereby providing enhanced performance, reliability, and manufacturing efficiency.

[0063] Figure 2This is a flowchart of a method 200 for transferring a microdevice from a housing substrate to a system substrate according to at least one embodiment. In at least one embodiment, method 200 begins at operation 210 by coating the housing substrate with a biodegradable layer. In at least one embodiment, the biodegradable layer is a release layer and facilitates the release of the microdevice to the system substrate. In at least one embodiment, the housing substrate may comprise glass, silicon, ceramic, or sapphire, and the biodegradable layer is a thermally degradable polymer (TDP). In at least one embodiment, the TDP layer is patterned. In at least one embodiment, method 200 continues at operation 220 by positioning a diaphragm structure having a flat bonding region over the biodegradable layer. In at least one embodiment, the diaphragm structure may be secured to the housing substrate through designated openings using anchors. In at least one embodiment, method 200 continues at operation 230 by bonding the microdevice to the diaphragm structure using an adhesive layer. In at least one embodiment, method 200 continues at operation 240 by heating the housing substrate and decomposing the biodegradable layer. In at least one embodiment, the housing substrate undergoes a controlled heating process to decompose the TDP layer, thereby releasing the diaphragm structure. In at least one embodiment, method 200 continues at operation 250 by bonding the microdevice to the system substrate and transferring it by aligning the diaphragm structure with the system substrate. In at least one embodiment, method 200 terminates at operation 260 by removing the diaphragm structure. Box - Release Layer

[0064] In at least one embodiment, the microdevice may be coupled to a diaphragm attached to a housing substrate. In at least one embodiment, the structure for the housing substrate includes a release layer and a diaphragm attached to the housing substrate at at least one point. In at least one embodiment, the microdevice is bonded to a flat surface of the diaphragm using an adhesive material. The release layer is removed before transferring the microdevice from the housing substrate to a system substrate. The release layer may be a biodegradable polymer, wherein a temperature-activated process removes it from the housing substrate in a manner similar to that described above.

[0065] In at least one embodiment, a biodegradable polymer layer (having a temperature threshold) is deposited on the surface of a housing substrate. The biodegradable polymer layer is patterned to form a release layer. In at least one embodiment, patterning can be accomplished by masking and dry etching. The mask can be a photoresist or coating, such as a metal or dielectric. In at least one embodiment, an anchoring material is formed on top of the release layer and is attached to the housing substrate at at least one point. In at least one embodiment, the anchoring material can be mechanically coupled to the housing substrate. In at least one embodiment, additional layers can be implemented between the anchoring material and the housing substrate. In at least one embodiment, the anchoring material can be a metal, dielectric, or other polymer. In at least one embodiment, the anchoring material can be formed using various deposition techniques, such as plasma-enhanced chemical vapor deposition (PECVD), electron beam, sputtering, coating, printing, or any other fabrication technique for thin film deposition. In at least one embodiment, the anchoring material is patterned to have a flat surface for coupling to a microdevice. In at least one embodiment, coupling can be performed via an adhesive layer.

[0066] In at least one embodiment, the microdevice is bonded to the adhesive layer and remains on the flat surface of the anchor. In at least one embodiment, the adhesive layer may have a sacrificial layer that can be separated from the anchor or the device. In at least one embodiment, the adhesive layer is part of the microdevice bonded to the flat surface of the anchor.

[0067] Before transferring the microdevice from the housing substrate to the system substrate, a temperature-activated process is used to decompose and release the structure. In at least one embodiment, the microdevice is aligned with and bonded to the system substrate. In at least one embodiment, the bonding between the microdevice and the substrate can be stronger than the anchoring force, thus removing the microdevice from the housing substrate. In at least one embodiment, the first adhesive layer can be removed from the microdevice by dry etching or wet etching. In at least one embodiment, a sacrificial layer is used, and this layer can be removed to separate the adhesive layer.

[0068] Figure 3 A box structure 300 is illustrated. In at least one embodiment, the box structure 300 includes a microdevice 308 coupled to a box substrate 302 via a diaphragm structure 306. In at least one embodiment, the box structure 300 further includes a thermally degradable polymer (TDP) as a release layer 304 between the box substrate 302 and the diaphragm structure 306.

[0069] In at least one embodiment, the release layer 304 and the diaphragm structure 306 are attached to the housing substrate at specific anchor points. In at least one embodiment, the housing structure 300 allows for precise control during the microdevice transfer process. In at least one embodiment, the microdevice 308 is initially bonded to the diaphragm structure 306, characterized by a flat surface designed for optimal adhesion. An adhesive layer 310 facilitates bonding, and the release layer 304 facilitates efficient and selective transfer of the microdevice 308 to the system substrate.

[0070] In at least one embodiment, a release layer 304 is formed on top of the housing substrate 302. In at least one embodiment, the release layer 304 is formed using a thermally decomposable polymer (TDP) or other decomposable material that can be removed by controlled heating. In at least one embodiment, the decomposition of the release layer 304 allows the diaphragm structure 306 and the attached microdevices 308 to be effectively detached and transferred.

[0071] In at least one embodiment, the release layer 304 has at least one opening to allow the diaphragm structure 306 to contact the housing substrate 302 or material on the surface of the housing substrate 302. In at least one embodiment, the diaphragm structure 306 is formed on top of the release layer 304. In at least one embodiment, the diaphragm structure 306 includes an anchor 306B connected to the housing substrate 302 through the opening. In at least one embodiment, the diaphragm structure 306 has an upper surface 306A. In at least one embodiment, the upper surface 306A is flat and can support the microdevice 308.

[0072] In at least one embodiment, the microdevice 308 is bonded to the upper surface 306A via an adhesive layer 310. In at least one embodiment, the adhesive layer 310 may be formed on the diaphragm structure 306. In at least one embodiment, after deposition, the adhesive layer 310 may be patterned to cover the upper surface 306A of the diaphragm structure 306. In at least one embodiment, the adhesive layer 310 may comprise one of the following: polyamide, photoresist material (such as SU-8 (an epoxy-negative photoresist)), BCB (often used to form photosensitive polymers), or other types of polymers. In at least one embodiment, the adhesive layer 310 may be formed on the microdevice 308. In at least one embodiment, the cassette structure 300 may be examined and its performance characteristics for parameters useful for high-yield transfer may be measured.

[0073] In at least one embodiment, the housing substrate 302 may comprise one of the following: glass, silicon, ceramic, or sapphire. In at least one embodiment, the housing substrate 302 is selected to match one or more properties of the system substrate to facilitate the transfer process. In at least one embodiment, reducing the thermal expansion mismatch between the housing substrate 302 and the system substrate is useful. In at least one embodiment, one or more layers may be added to the top surface 302A of the housing substrate 302 to enhance adhesion or other properties. In at least one embodiment, enhancing the adhesion between the diaphragm structure 306 and the housing substrate 302 may be useful.

[0074] In at least one embodiment, the housing substrate 302 may include different types of alignment marks for various alignment processes. In at least one embodiment, there may be a first set of alignment marks for transferring the microdevice 308 into the housing substrate 302, a second set of alignment marks for processing the housing structure 300, and a third set of alignment marks for transferring the microdevice 308 from the housing substrate 302 to the system substrate. In at least one embodiment, the alignment marks may also be shared by other processes.

[0075] In at least one embodiment, the release layer 304 can be formed by the following sequence of operations. In at least one embodiment, initially, a biodegradable polymer layer can be uniformly deposited onto the surface of the housing substrate 302. In at least one embodiment, the biodegradable polymer layer can be selected based on its decomposition temperature, adhesion properties, and compatibility with the microdevice and subsequent processing steps. In at least one embodiment, after deposition, the biodegradable polymer layer is patterned to form the release layer 304. In at least one embodiment, the patterning method can include masking and dry etching the biodegradable polymer layer using a photoresist, metal, or dielectric material as a mask. In at least one embodiment, laser-assisted ablation can be used to precisely and locally remove material. In at least one embodiment, microimprint lithography can be used to form ultrafine patterns. In at least one embodiment, an anchoring material is formed over the release layer to hold the diaphragm structure 306 in a specific location. In at least one embodiment, the anchoring material can be composed of a metal (such as aluminum, gold, or copper), a dielectric (such as silicon nitride or silicon oxide), or a high-temperature polymer. In at least one embodiment, the anchoring material is patterned to include a flat, smooth surface, thereby optimizing its adhesion to the adhesive layer 310. In at least one embodiment, the anchors are connected at useful points to ensure that the diaphragm structure 306 maintains mechanical integrity during processing, but can be detached if needed. In at least one embodiment, the anchoring layer may further include a buffer layer to manage stress between the diaphragm structure 306 and the housing substrate 302, thereby ensuring durability during thermal cycling.

[0076] In at least one embodiment, the microdevice 308 is bonded to the upper surface 306A via an adhesive layer 310. The adhesive layer 310 may be formed on the diaphragm structure 306. In at least one embodiment, after deposition, the adhesive layer 310 may be patterned to cover the upper surface 306A of the diaphragm structure 306. In at least one embodiment, the adhesive layer 310 may comprise one of polyamide, SU8, BCB, or a UV-curable adhesive, selected based on their mechanical and thermal properties. In at least one embodiment, the adhesive layer 310 may be formed on the microdevice 308. In at least one embodiment, the adhesive layer 310 may incorporate a sacrificial layer designed to be selectively removed after transfer. In at least one embodiment, the sacrificial layer allows the microdevice to detach cleanly from the diaphragm structure 306 after bonding. In at least one embodiment, the adhesive layer 310 is patterned to substantially match the shape of the microdevice 308 and prevent overflow. In at least one embodiment, overflow may interfere with bonding accuracy.

[0077] Before the transfer begins, the cassette structure 300 undergoes inspection to ensure that all microdevices (such as microdevice 308) are correctly aligned and securely bonded to the cassette substrate 302. In at least one embodiment, prior to the transfer, the cassette structure 300 is subjected to detailed inspection using optical microscopy, X-ray imaging, or thermal distribution analysis to ensure that all microdevices are correctly positioned and securely bonded.

[0078] In at least one implementation, the box structure 300 can be examined and measured for performance characteristics and other parameters useful for high-yield transfers.

[0079] Figure 4 This is a diagram of box structure 400. In at least one embodiment, box structure 400 is constructed after the decomposition process of release layer 304. Figure 3 A diagram of box structure 300. (See also: Common Reference) Figure 3 and Figure 4 In at least one embodiment, after measurement and inspection, the housing structure 300 undergoes a release process, wherein a temperature-activated process is used to decompose the release layer 304. In at least one embodiment, the release process may be gradual to avoid damage to the housing structure 300. In at least one embodiment, the release process involves controlled heating to decompose the release layer 304. In at least one embodiment, staged heating can prevent thermal stress and potential damage to the microdevice 308 or the diaphragm structure 306. Localized polymer decomposition using lasers or targeted heating

[0080] In at least one embodiment, alternative methods such as localized laser heating or infrared (IR) light exposure can also be used for precise decomposition. In at least one embodiment, the release layer 304 is decomposed, and the diaphragm structure 306 becomes free for transfer.

[0081] In at least one embodiment, the cassette structure 300 is then loaded into an alignment tool to ensure proper positioning of the diaphragm and attached microdevices 308 relative to the cassette substrate 302. In at least one embodiment, after the release layer 304 is removed, the cassette structure 300 can be further inspected as it is inserted into a tool designed to hold and align it with the system substrate. In at least one embodiment, the cassette substrate 302 is brought into contact with the system substrate, and a selected set of microdevices 308 is bonded to the system substrate. In at least one embodiment, the selected set of microdevices 308 is bonded to the system substrate using mechanical pressure, heat, or a combination of both. In at least one embodiment, the bonding strength between the microdevices 308 and the system substrate is designed to be greater than the anchoring force, thereby facilitating clean removal from the cassette structure 300.

[0082] In at least one embodiment, after transfer, the diaphragm structure 306 can detach naturally, or the bonding adhesive can be selectively dissolved or etched away (using dry or wet etching techniques). In at least one embodiment, the transfer process includes disrupting the diaphragm structure 306 or separating the microdevices 308 from the adhesive layer 310 (bonding material). This process leaves the selected set of microdevices 308 on the system substrate.

[0083] In at least one embodiment, a secondary or tertiary inspection phase may be performed after transfer to confirm the quality of the bonding between the microdevice 308 and the system substrate 302. In at least one embodiment, residual adhesive or decomposed material is removed by plasma cleaning, wet etching, or ultrasonic cleaning to ensure a clean, high-quality final product.

[0084] In at least one embodiment, a multilayer release structure can be implemented. In at least one embodiment, the release layer 304 can be replaced by a multilayer structure comprising multiple biodegradable polymer layers. In at least one embodiment, each layer can have a unique decomposition temperature. This layered approach enables staged release of microdevices, thereby allowing selective transfer or multi-step integration processes. In at least one embodiment, the lower layer within the multilayer structure can be designed to release first under a first thermal condition, followed by the upper layer releasing under a second thermal condition (such as at different temperatures). In at least one embodiment, the lower layer can be in contact with the housing substrate 302. Releasing multiple layers can be useful for integrating complex arrays of microdevices or when multiple transfer stages are required.

[0085] In at least one embodiment, a laser-activated release layer may be implemented in the box structure 300. In at least one embodiment, the release layer 304 may be sensitive to a specific wavelength of laser light, thereby enabling selective and localized decomposition. In at least one embodiment, implementing a laser-activated release layer may be beneficial for transferring delicate microdevices or in scenarios requiring high precision, as it eliminates the risk of thermal damage to adjacent structures.

[0086] In at least one embodiment, the release layer 304 may be chemically degradable. In another approach, the release layer 304 may be designed to decompose upon exposure to a specific chemical vapor or solution. In at least one embodiment, implementing a chemically degradable release layer 304 allows for controlled release without requiring high temperatures. In at least one such embodiment, this process may be suitable when the microdevice 308 is temperature-sensitive.

[0087] In at least one embodiment, the box structure 300 may incorporate a reusable diaphragm structure 306. In at least one embodiment, the diaphragm structure 306 may be designed for reuse to improve process efficiency and provide sustainability. In at least one embodiment, the diaphragm structure 306 can be cleaned and reprocessed after the release and transfer process, thereby allowing for multiple cycles of microdevice bonding and transfer. In at least one embodiment, for this reusable approach, materials such as high-strength silicone, advanced polymers, or metals with protective coatings may be incorporated.

[0088] In at least one embodiment, gradient adhesive bonding can be implemented. In at least one embodiment, the adhesive layer 310 has a gradient composition and a bonding strength that varies across the surface. In at least one embodiment, this variation can occur at the surface in contact with the diaphragm structure 306. In at least one embodiment, an adhesive layer 310 with a gradient composition may be useful because microdevices at some locations can be bonded more firmly, while microdevices at other locations can be easily released. In at least one embodiment, this method allows for precise control of selective transfer and can be applied to high-density or heterogeneous integration processes.

[0089] In at least one embodiment, the release layer 304 may be a self-healing polymer layer. After decomposition and transfer, the remaining structure can be repaired in situ, thereby extending the service life of the box structure 300 and reducing material waste.

[0090] In at least one embodiment, the microdevice is coupled to a cell substrate using a material with a low glass transition temperature. The glass-liquid transition, or glass transition, is a gradual and reversible transformation process in an amorphous material (or an amorphous region within a semi-crystalline material) from a hard and relatively brittle glassy state to a viscous or rubbery state with increasing temperature. Amorphous solids exhibiting a glass transition are called glasses. In at least one embodiment, the glass transition temperature can range from 140°C to 370°C, depending on the grade of the amorphous or semi-crystalline material, the curing process, and the moisture content. The glass transition temperature T of the material... G The temperature range in which the glass transition occurs is characterized. In at least one embodiment, from an experimental perspective, the temperature relaxation time can be approximately 100 s.

[0091] In at least one embodiment, the cell substrate may include one of the following: glass, silicon, ceramic or sapphire, and provide a stable substrate for subsequent layers.

[0092] Figure 5 An illustration of structure 500 is shown. In at least one embodiment, structure 500 includes a microdevice 508 integrated on a cell substrate 502 using a low glass transition temperature (LGT) material 504, which is implemented for cell development. In at least one embodiment, the LGT material 504 may be formed on top of the cell substrate 502.

[0093] In at least one embodiment, the microdevice 508 is coupled to the housing substrate 502 using a material with a low glass transition temperature (Tg). In at least one embodiment, the LGT material 504 can be used to facilitate precise bonding and transfer of the microdevice 508 from the housing substrate 502 to the system substrate. In at least one embodiment, the LGT material 504 includes controllable adhesion properties, thereby enabling efficient microdevice handling, bonding, and release under specific thermal conditions. In at least one embodiment, the LGT material 504 provides handling flexibility, especially when temperature-sensitive microdevices are involved. In at least one embodiment, the LGT material 504 can be a thermally decomposable material and can be cleaned after transfer. In at least one embodiment, the LGT material 504 can be used with a low glass transition temperature (Tg). G The material is deposited uniformly. In at least one embodiment, a low glass transition temperature T G Controlled softening and decomposition can be facilitated during the bonding process. In at least one embodiment, an additional material layer may be present between the cell substrate 502 and the LGT material 504.

[0094] In at least one embodiment, bonding pads 510 may be formed on top of LGT material 504, and microdevices 508 may be bonded to bonding pads 510. In at least one embodiment, bonding pads 510 allow selective integration of one or more microdevices (such as microdevices 508) from a microdevice array into a housing substrate 502. In at least one embodiment, bonding pads may be interposed between LGT material 504 and microdevices 508 to facilitate selective bonding and efficient transfer.

[0095] In at least one embodiment, a buffer layer or adhesion enhancement layer may be inserted between the cell substrate 502 and the LGT material 504 to optimize adhesion and manage stress. This configuration allows for the selective release of microdevices upon controlled heating, thereby ensuring that only the intended devices are transferred while maintaining the integrity of the remaining structure.

[0096] In at least one embodiment, the housing substrate 502 comprises one of the following: glass, silicon, ceramic, or sapphire, providing a stable substrate for subsequent layers. In at least one embodiment, the pads may be identical to the LGT layer. In at least one embodiment, microdevices may be precisely positioned and bonded to the bonding pads or the LGT layer.

[0097] To transfer at least a single microdevice 508 from the housing substrate 502 to the system substrate, the structure 500 is aligned with the system substrate. In at least one embodiment, a selective transfer process may be implemented. In at least one embodiment, thermal energy is applied during transfer to reduce adhesion between the LGT material 504 and adjacent materials. In at least one embodiment, the LGT material 504 is located between the housing substrate 502 and the bonding pads 510 in the structure 500. In at least one such embodiment, thermal energy is applied to reduce adhesion between the LGT material 504 and the bonding pads 510, and between the LGT material 504 and the housing substrate 502. In at least one embodiment, thermal energy is applied to achieve a clean and efficient release of the microdevice 508.

[0098] Figure 6 Structure 500 is illustrated. In at least one embodiment, structure 500 includes a microdevice 508 integrated into a cell substrate 502 for cell development.

[0099] In at least one embodiment, there may be no bonding pad 510 between the microdevice 508 and the LGT material 504. In one such embodiment, the microdevice 508 may be directly bonded to the LGT material 504. In at least one embodiment, the LGT material 504 may be patterned or formed as a continuous layer. This structure allows all microdevices from the microdevice array to be integrated into the system substrate.

[0100] In at least one embodiment, the bonding pad 510 is on top of the housing substrate 502. In at least one such embodiment, the bonding pad 510 is between the LGT material 504 and the housing substrate 502. In at least one embodiment, additional layers, such as a buffer layer or an adhesion enhancement layer, may be included between the housing substrate 502 and the bonding pad 510. In at least one such embodiment, an additional layer may be inserted below the bonding pad 510 on the surface 502A of the housing substrate 502. In at least one embodiment, the bonding pad 510 has a height selected to reduce or avoid interference during microdevice bonding. In at least one embodiment, sufficient height of the bonding pad 510 may help eliminate interference between the housing and other devices during transfer from the housing substrate 502 to the system substrate.

[0101] In at least one embodiment, a structured pad configuration can be implemented to enhance the transfer process. In at least one embodiment, the bonding pad 510 can be formed by depositing a pad layer over the housing substrate 502. In at least one embodiment, the pad layer can be patterned to form the bonding pad 510. In at least one embodiment, the pad layer is not patterned until after the LGT material 504 is deposited. In at least one embodiment, when the pad layer is patterned and formed into the bonding pad 510, it can be used for alignment, conductivity, and mechanical support. In at least one embodiment, the LGT material 504 is applied or deposited over the bonding pad 510. In at least one embodiment, the LGT material 504 contacts the bonding pad 510. In at least one embodiment, selective patterning is performed to match the shape of the bonding pad 510, as shown. In at least one embodiment, the microdevice 508 is bonded to the bonding pad 510 coated with the LGT material 504. In at least one embodiment, the height of the bonding pad 510 can be adjusted to reduce interference during bonding and transfer operations.

[0102] In at least one embodiment, the bonding pad 510 may be made of a conductive material or an adhesive material (such as a metal or a specialized polymer) to ensure a strong initial bond and facilitate electrical connection when needed. In at least one embodiment, additional layers may be present between the bonding pad 510 and the housing substrate 502, between the bonding pad 510 and the LGT material 504, or between the LGT material 504 and the microdevice 508. In at least one embodiment, one or more additional layers include a buffer layer or an adhesion enhancement layer. In at least one embodiment, the adhesion enhancement layer or buffer layer may be applied before or after the formation of the bonding pad 510, or after the formation of the bonding pad 510 but before the formation of the LGT material 504.

[0103] To transfer at least a single microdevice 508 from the housing substrate 502 to the system substrate, structure 600 is aligned with the system substrate. In at least one embodiment, a selective transfer process can be implemented. In at least one embodiment, thermal energy is applied during transfer to reduce adhesion between the LGT material 504 and adjacent materials. In at least one embodiment, in structure 600, the LGT material 504 is located between the microdevice 508 and the bonding pad 510. In at least one such embodiment, thermal energy is applied to reduce adhesion between the LGT material 504 and the bonding pad 510, and between the LGT material 504 and the microdevice 508. In both embodiments, thermal energy is applied to achieve a clean and efficient release of the microdevice 508. The method utilized is particularly useful for batch transfer processes that simultaneously bond and transfer multiple microdevices.

[0104] As a variation of structure 600, in at least one embodiment, microdevice 508 is bonded to LGT material 504 without intermediate bonding pads 510. This simplified method simplifies the manufacturing process and improves bonding efficiency. In at least one embodiment, LGT material 504 is uniformly deposited and can cover the surface of the housing substrate 502. In at least one embodiment, LGT material 504 can be formed as a continuous layer. In at least one embodiment, LGT material 504 can be patterned according to device specifications. In at least one embodiment, microdevice 508 is directly bonded to LGT material 504 using a temperature-controlled process, thereby ensuring sufficient adhesion while allowing easy release upon heating. In at least one embodiment, during transfer, thermal energy is applied to reduce adhesion between LGT material 504 and adjacent materials, thereby achieving clean and efficient microdevice release.

[0105] The selected microdevice 508 is bonded to the system substrate at a temperature that reduces the adhesion of the LGT.

[0106] In at least one embodiment, structure 500 can be implemented using a multilayer structure comprising two or more LGT materials. Figure 5 ) or structure 600 ( Figure 6 ).

[0107] Figure 7 A cross-section of a structure 700 including a multilayer structure 702 in at least one embodiment is illustrated, the multilayer structure comprising two or more LGT materials. In at least one embodiment, the multilayer structure 702 can facilitate selective transfer capability. In at least one embodiment, the multilayer structure 702 may include a primary LGT layer 702A and a secondary LGT layer 702B on the primary LGT layer 702A. In at least one embodiment, the primary LGT layer 702A and the secondary LGT layer 702B comprise materials related to LGT material 504 (… Figure 5The primary LGT layer 702A and the secondary LGT layer 702B are made of the same or substantially the same material, but differ from each other. In at least one such embodiment, the difference may arise from material or property differences discussed below. In at least one embodiment, the primary LGT layer 702A provides initial adhesion and structural support. In at least one embodiment, the secondary LGT layer 702B may be formulated to have a decomposition temperature different from that of the primary LGT layer 702A. In at least one embodiment, the difference in decomposition temperature is designed to facilitate staged release of the microdevices. Staged release can enable selective transfer, where some microdevices are released earlier than others based on a controlled heating profile. In at least one embodiment, one or more additional intermediate layers (such as adhesion enhancement layers) may be added to fine-tune adhesion strength, thermal management, or mechanical stability. In at least one embodiment, the multilayer structure 702 can support multi-stage transfer processes and can be adapted to complex arrays integrating heterogeneous microdevices.

[0108] Figure 8 A cross-section of structure 800, comprising a multilayer structure 702, is illustrated in at least one embodiment, the multilayer structure comprising two or more LGT materials. In at least one embodiment, structure 800 is structure 600 ( Figure 6 A variation of the original LGT material 504 is provided, wherein the single-layer LGT material 504 is replaced by a multilayer structure 702. In at least one embodiment, the multilayer structure 702 can facilitate selective transfer capability. In at least one embodiment, the multilayer structure 702 includes a primary LGT layer 702A and a secondary LGT layer 702B on the primary LGT layer 702A. In at least one embodiment, the multilayer structure 702 is located between the microdevice 508 and the bonding pad 510.

[0109] Refer again Figures 5 to 6 In at least one embodiment, different thermal strategies can be implemented to facilitate the transfer of microdevices from the LGT material 504. In at least one embodiment, the cell substrate 502 is aligned with the system substrate, and heat is applied to reduce the adhesion of the LGT material 504. In at least one embodiment, the decomposition temperature is controlled to be close to but not exceed the glass transition temperature (T0) of the LGT material 504. G In at least one embodiment, a controlled temperature rise can provide a smooth and efficient release without damaging the sensitive microdevice. In at least one embodiment, after transfer, any remaining residual LGT material 504 can be cleaned or etched from the microdevice and substrate to provide a clean bonding interface.

[0110] In at least one embodiment, the LGT material 504 is formulated to be thermally decomposed during the transfer process, with the temperature increasing above a decomposition threshold, resulting in evaporation or degradation of the LGT material 504 layer. In at least one embodiment, evaporation or degradation can facilitate the clean separation of the microdevice 508 from the housing substrate 502, leaving little or no residue. In at least one embodiment, after transfer, residual contaminants can be removed using a cleaning process including plasma treatment and / or solvent cleaning.

[0111] In at least one embodiment, a laser or photoinduced transfer process can be performed to remove the microdevice 508 from the housing substrate 502. In at least one embodiment, a laser or photoinduced heating process can be performed to locally increase the temperature of the LGT material 504 of a selected microdevice. In at least one embodiment, applying localized heating to a specific region of the housing substrate 502 can provide precision in removing the microdevice 508. In at least one embodiment, precise removal can be useful for selectively and locally transferring microdevices without affecting adjacent microdevices. In at least one embodiment, the wavelength and intensity of the laser can be tuned based on the specific decomposition characteristics of the LGT material 504.

[0112] In at least one embodiment, a reusable substrate cassette design can be implemented to enhance sustainability and reduce manufacturing costs. In at least one embodiment, after transferring the microdevice 508, residual LGT material 504 can be cleaned or heat-treated to remove decomposition residues. This method can be applied where the LGT material 504 is directly on the cassette substrate 502. In at least one embodiment, the LGT material 504 is reapplied or deposited, and the cassette substrate 502 can be reprocessed for subsequent bonding cycles. In at least one embodiment, the reusability of the cassette substrate 502 can be supported by using durable substrate materials such as sapphire, reinforced glass, or coated ceramics that can withstand multiple thermal cycles without degradation.

[0113] In at least one embodiment, a hybrid LGT material 504 may be implemented. In at least one embodiment, such a hybrid LGT material 504 may have self-healing properties. In at least one embodiment, the hybrid LGT material 504 can extend the lifespan of the cartridge and improve process efficiency. In at least one embodiment, after decomposition and transfer, the hybrid LGT material 504 comprising the self-healing polymer can be activated via controlled heating or ultraviolet exposure, thereby allowing the hybrid LGT material 504 layer to reform and become smooth for subsequent microdevice bonding. In at least one embodiment, implementing a hybrid LGT material 504 can reduce material waste and the need for continuous reapplication of the LGT material 504, thereby simplifying the manufacturing process.

[0114] Following the transfer, cleaning and quality inspection of the system substrate are critical for the manufacturing process. In at least one embodiment, the system substrate can be cleaned and inspected after the transfer of microdevice 508 to ensure product quality. In at least one embodiment, residue cleaning can be performed by one of the following methods: plasma treatment, solvent immersion, or chemical etching, to remove residual LGT material 504 from the transferred microdevice and system substrate. In at least one embodiment, visual and structural inspections can be performed for quality assurance. In at least one embodiment, visual and structural inspections can include one of the following: optical microscopy, scanning electron microscopy (SEM), or X-ray analysis, to inspect the cleaned bonding interfaces for structural integrity. In at least one embodiment, adhesion strength can be tested. In at least one embodiment, adhesion strength can be measured by performing mechanical tests (such as peel or shear tests) to confirm the integrity of the transferred microdevice.

[0115] In some cases, well-known methods and devices are shown in block diagram form rather than in detail to avoid obscuring at least one embodiment. Throughout this specification, the terms "implementation," "an embodiment," "in at least one embodiment," or "some embodiments" refer to a specific feature, structure, function, or characteristic described in connection with that embodiment, which is included in at least one embodiment. Therefore, the phrases "in an embodiment," "in at least one embodiment," "in one embodiment," or "some embodiments," when appearing in multiple places throughout this specification, do not necessarily refer to the same embodiment disclosed. Furthermore, specific features, structures, functions, or characteristics can be combined in one or more embodiments in any suitable manner. For example, the two embodiments can be combined wherever specific features, structures, functions, or characteristics associated with the first and second embodiments are not mutually exclusive.

[0116] As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and covers all possible combinations of one or more items in the associated list.

[0117] Herein, “coupling” and “connection”, and their derivatives, are used to describe functional or structural relationships between components. These terms are not intended to be synonyms. Rather, in certain examples, “connection” can be used to indicate that two or more elements are in direct physical, optical, or electrical contact with each other. “Coupling” can be used to indicate that two or more elements are in direct or indirect physical, electrical, or magnetic contact with each other (with other elements in between), and / or that two or more elements cooperate or interact with each other (e.g., as in a causal relationship).

[0118] Herein, the terms “above,” “below,” “between,” and “on” as used herein refer to the relative position of a component or material with respect to other components or materials, where such physical relationships are noteworthy. For example, in the context of materials, a material or material disposed above or below another material may be in direct contact, or may have one or more materials in between. Furthermore, a material disposed between two materials may be in direct contact with both layers, or may have one or more layers in between. Conversely, a first material “on” a second material is in direct contact with that second material / material. Similar distinctions are made in the context of component assemblies. As used throughout this specification and in the claims, a list of items connected by the terms “at least one of…” or “one or more of…” may refer to any combination of the listed terms.

[0119] Here, "adjacent" usually refers to the position where one thing is right next to (e.g., adjacent to or close to and with one or more things in between) or adjacent to another thing (e.g., next to it).

[0120] Here, "signal" can refer to current signal, voltage signal, magnetic signal, or data / clock signal.

[0121] Here, "device" may refer to a device depending on the context in which the term is used. For example, a device may refer to a stack of layers or structures, a single structure or layer, or a connection of various structures with active and / or passive components. Typically, a device is a three-dimensional structure having a plane along the xy direction of the xyz Cartesian coordinate system and a height along the z direction. In at least one example, the plane of the device may also be the plane of the apparatus that includes the device.

[0122] Unless otherwise stated in the explicit context in which they are used, the terms "substantially equal," "approximately equal," and "nearly equal" mean that there is no variation beyond chance between the two things described. This variation is generally no greater than + / - 10% of a predetermined target value.

[0123] Here, the terms “left,” “right,” “front,” “back,” “top,” “bottom,” “above,” “below,” and similar terms are used for descriptive purposes and not necessarily to describe permanent relative positions. For example, the terms “above,” “below,” “front side,” “back side,” “top,” “bottom,” “above,” “below,” and “on” as used herein refer to the relative position of a component, structure, or material within a device relative to other referenced components, structures, or materials, where such physical relationships are noteworthy. These terms are used only for descriptive purposes herein and primarily in the context of the device’s z-axis, and therefore may be relative to the device’s orientation. Thus, if the device is oriented inverted relative to the context of the provided figures, a first material “above” the second material may also be “below” the second material in the context of the provided figures. A similar distinction should be made in the context of component assemblies.

[0124] Here, "between" can be applied in the context of the z-axis, x-axis, or y-axis of a device. A material situated between two other materials can contact one or both of those materials. In another example, a material situated between two or more other materials can be separated from the other two materials by one or more intermediate materials. Therefore, a material "between" two other materials can contact either of the other two materials. In another example, a material "between" two other materials can be coupled to the other two materials by the intermediate material. A device situated between two other devices can be directly connected to one or both of those devices. In another example, a device situated between two other devices can be separated from the other two devices by one or more intermediate materials.

[0125] While examples and applications of this disclosure have been illustrated and described, it should be understood that this disclosure is not limited to the precise structure and composition disclosed herein, and various modifications, alterations and variations may be apparent from the foregoing description without departing from the spirit and scope of this disclosure as defined by the appended claims.

Claims

1. A method for integrating microdevices into a system substrate using a biodegradable polymer in a MicroSolid printing process, the method comprising: Metallization of a substrate is achieved by mixing metal powder into the decomposable polymer under light or temperature. Patterning is achieved using printing techniques; as well as The decomposable polymer is decomposed to sinter the metal powder.

2. The method of claim 1, wherein multiple metals are used to achieve sintering and high conductivity at a first process temperature.

3. The method according to claim 2, wherein the plurality of metals includes powders of silver and indium.

4. The method according to claim 1, wherein the biodegradable polymer is mixed with conductive nanoparticles.

5. The method of claim 4, wherein the material is formed on the receiving substrate in the form of bumps, and the microdevice is bonded at a second temperature at least equal to the first glass transition temperature of the decomposable polymer.

6. The method of claim 5, wherein after transferring the microdevice, pressure or a third temperature is applied to decompose the decomposable polymer, thereby leaving the conductive nanoparticles between the microdevice and the conductive pads in the system substrate.

7. The method according to claim 6, wherein the conductive nanoparticles are metals or other conductive materials.

8. The method of claim 6, wherein two or more materials facilitate the mechanical bonding of the microdevice to the conductive pad.

9. The method of claim 4, wherein the biodegradable polymer covers the surface of the system substrate, and wherein the microdevice is bonded to the system substrate at a fourth temperature above the second glass transition temperature of the biodegradable polymer.

10. The method of claim 9, wherein after bonding, a second temperature or pressure is used to decompose the biodegradable polymer beneath the microdevice pads and form a conductive connection between the contact on the system substrate and the microdevice pads.

11. The method of claim 10, wherein a solution is used to remove residual biodegradable polymer and particles embedded in the biodegradable polymer from the surface of the system substrate.

12. The method of claim 4, wherein the biodegradable polymer is deposited on top of the conductive bumps, and wherein the microdevice is bonded to the conductive pads after the biodegradable polymer has decomposed.

13. A method for integrating microdevices into a system substrate, the method comprising: The box substrate is coated with a biodegradable polymer layer; The membrane structure is positioned above the biodegradable polymer layer; The microdevices are bonded to the diaphragm structure using an adhesive layer; Heating the substrate and decomposing the biodegradable polymer layer; The microdevice is bonded to the system substrate and transferred by aligning the diaphragm structure with the system substrate; as well as Remove the membrane structure.

14. The method of claim 13, wherein the biodegradable polymer layer and the membrane structure are connected to the housing substrate at an anchor point.

15. The method of claim 13, wherein the diaphragm structure includes a flat junction region, and wherein the microdevice is coupled to the flat junction region of the diaphragm structure.

16. The method of claim 13, wherein the diaphragm structure includes anchors connected to the housing substrate through openings in the diaphragm structure.

17. The method of claim 13, wherein the adhesive comprises one of the following: polyamide, or a photoresist material comprising one of SU-8 or benzocyclobutene.

18. The method of claim 13, wherein the biodegradable polymer comprises one of the following: poly(methyl methacrylate) (PMMA), polystyrene (PS), polypropylene carbonate (PPC), or a photoresist.

19. The method of claim 13, wherein the cell substrate comprises one of the following: glass, silicon, ceramic, or sapphire.

20. The method of claim 13, wherein prior to positioning the membrane structure, the method further comprises patterning the biodegradable polymer to form a release layer.

21. The method of claim 13, wherein decomposing the decomposable polymer layer further comprises using localized laser-assisted ablation or infrared (IR) light exposure for precise decomposition.

22. The method of claim 13, wherein an anchoring material is formed over the biodegradable polymer layer to secure the diaphragm structure, wherein the anchoring material comprises one of a conductor, a dielectric, or a polymer.

23. A method for integrating microdevices into a system substrate using a biodegradable polymer, the method comprising: A bonding pad is formed on the system substrate; A system substrate is coated with a biodegradable layer, wherein the biodegradable polymer surrounds the bonding pads; Align the microdevice, including the pads, over the bonding pads; Join the pads to the bonding pads; as well as The decomposable layer is decomposed by applying temperature and pressure, and the bonding pads are fused together.

24. The method of claim 23, wherein the pads comprise a conductive material.

25. The method of claim 23, wherein the bonding pad comprises one of the following: indium, gold, copper, tin, tungsten, carbon nanotubes, or silver.

26. The method of claim 23, wherein after forming the bonding pad, the method further comprises forming a dielectric on at least the sidewall of the bonding pad.

27. The method of claim 26, wherein the dielectric comprises silicon and one of oxygen, nitrogen, or carbon.

28. The method of claim 27, wherein bonding the microdevice comprises contacting the pad with the dielectric.

29. The method of claim 23, wherein bonding the pad to the bonding pad comprises bonding at a first temperature above the glass transition temperature of the decomposable polymer.

30. A method for integrating microdevices into a system substrate, the method comprising: A bonding pad is formed on the system substrate; The system substrate is coated with a multilayer stack of biodegradable polymers, wherein the multilayer stack of biodegradable polymers surrounds the bonding pads; Align the microdevice with the pad above the bonding pad; Join the pads to the bonding pads; as well as The multilayer stack of the decomposable polymer is decomposed by applying temperature and pressure, and the bonding pads are fused together.

31. The method of claim 30, wherein the multilayer stack of the biodegradable polymer comprises: A first layer of a first biodegradable polymer mixed with a first conductive nanoparticle and a second layer of a second biodegradable polymer including a second conductive nanoparticle, wherein the first layer is located on the second layer.

32. The method of claim 31, wherein the first conductive nanoparticle comprises silver or copper, and wherein the second conductive nanoparticle comprises silver nanowires or carbon nanotubes.

33. The method of claim 31, wherein bonding the pad to the bonding pad comprises bonding at a first temperature above the glass transition temperature of the first biodegradable polymer and the second biodegradable polymer.

34. A method for integrating microdevices into a system substrate, the method comprising: Bumps are formed on the system substrate; A system substrate is coated with a biodegradable polymer, wherein the biodegradable polymer surrounds the bumps; Align the microdevice and the pad above the bump; The pads are joined to the bumps; as well as The biodegradable polymer is decomposed by applying temperature and pressure, and the bump is fused to the pad.

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