Photoelectric micro device

Abstract

The invention relates to the development of micro devices on a substrate that can be released and transferred to a system substrate. The disclosure further relates to methods to integrate anchors to secure a micro device to a substrate. These micro devices are in different configurations relative to the anchor, release layer, buffer layer, and substrate.

Description

Technical Field

[0001] The present invention relates to the development of micro devices on a substrate that can be released and transferred to a system substrate. Summary of the Invention

[0002] The present invention relates to a method for integrating anchors to fix a microdevice to a substrate, the method comprising: forming at least two diaphragm layers on the substrate so that the at least two diaphragm structures are adapted below the surface of the microdevice, wherein the diaphragm structures are smaller than the microdevice surface in at least one dimension; and bonding the microdevice surface to these diaphragm structures with a bonding layer.

[0003] The present invention also relates to a method for transferring a micro device using a formed diaphragm, the method comprising: manufacturing a cassette diaphragm on a cassette substrate; inspecting the cassette substrate to identify defective areas before the transfer; and identifying good areas based on the number or type of defects per area.

[0004] The present invention also relates to a method for manufacturing microdevices on a microdevice substrate, the method comprising: dividing regions having the same size as or a smaller multiple of the islands in the cartridge substrate; inspecting the defects and performance of the microdevices based on predefined parameters; and separating the microdevice regions from the wafer, wherein each region is divided into different groups based on the final product performance requirements.

[0005] The present invention also relates to a method for filling a box island, which comprises: aligning a microdevice area substrate with an area of a good box island in the box substrate; bringing the two substrates close together so that the microdevices are bonded to the box diaphragm structure through a bonding material; and providing a release layer between the microdevice and the area substrate, wherein the release layer is delaminated by a chemical, laser, thermal, or mechanical process, thereby leaving the bonded microdevices on the material film structure.

[0006] The present invention also relates to a method for integrating anchors to secure a microdevice to a cartridge substrate, the method comprising: depositing release layers on the cartridge substrate; forming openings in the release layers; depositing and patterning anchors and membrane layers; extending a rearmost portion of the membrane layer to the release layer openings; and forming and patterning a bonding layer on top of the membrane layer.

[0007] The present invention also relates to a method for transferring microdevices, the method comprising: developing a mesa structure on a donor substrate, wherein the microdevice structure is formed by etching through different layers, a first bottom conductive layer, a functional layer and a second top conductive layer; depositing a top contact pad on top of the second top conductive layer before or after etching, wherein the top contact pad is deposited on top of the second top conductive layer before or after etching, and each microdevice includes a passivation layer and / or MIS layer surrounding each microdevice for isolation and / or protection; and providing these microdevices with different anchors, whereby after these microdevices are peeled off, the anchors fix the microdevices to the donor substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The foregoing and other advantages of the present disclosure will become apparent after reading the following detailed description and after referring to the accompanying drawings.

[0009] Figure 1A Cross-sectional views of microdevices with different anchors in the filling layer are shown.

[0010] Figure 1B A cross-sectional view of a micro device after post-processing the fill layer is shown.

[0011] Figure 1C Show Figure 1B Top view of the microdevice.

[0012] Figure 1D A cross-sectional view showing a transfer step for transferring a micro device to another substrate.

[0013] Figure 1E A cross-sectional view showing a micro device transferred to a substrate.

[0014] Figure 2A A micro device on a substrate and a release layer covering a portion of the micro device are shown.

[0015] Figure 2B The microdevice is shown secured to the substrate via anchors after deactivation or removal of the release layer.

[0016] Figure 2C Removal of the first substrate and the buffer layer from the micro device is shown.

[0017] Figure 2D Shown is a release layer being deposited and patterned.

[0018] Figure 3A Showing the offset anchor situation.

[0019] Figure 3B Another example showing an offset anchor.

[0020] Figure 4A A micro-device formed on top of a stage is shown.

[0021] Figure 4B exhibit Figure 4A A top view of the structure in .

[0022] Figure 5A The anchor is shown formed on top of the substrate.

[0023] Figure 5B exhibit Figure 5A A top view of an example.

[0024] Figure 5C The main portion of the anchor and the release layer are shown positioned below the microdevice.

[0025] Figure 6 A top view of another related embodiment for an integrated anchor is shown.

[0026] Figure 7A A smaller membrane structure / layer is shown formed on the substrate.

[0027] Figure 7B Another related example of a membrane structure for micro-device transfer is shown.

[0028] Figure 7C An example of patterning of a release layer on a substrate is shown.

[0029] Figure 8 Related embodiments related to the formation of membrane-based microdevice transfer are presented.

[0030] Figure 9A Exemplary process steps for filling a magazine island are shown.

[0031] Figure 9B It is shown that processing can continue on the same region substrate for the remaining micro devices, or on an entirely different region substrate with the same or different micro devices.

[0032] Figure 9C The demonstration microdevice is coupled to the region substrate via a patterned release layer.

[0033] Figure 9D An embodiment is shown where the exposed areas are covered by a protective layer.

[0034] Figure 10A Examples of box islands having shapes other than square or rectangular are shown.

[0035] Figure 10B An example is shown where the zones are aligned, and enough zones are used to cover the entire surface of the cartridge island.

[0036] The present disclosure is susceptible to various modifications and alternative forms, and specific embodiments or implementations have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the present disclosure is not intended to be limited to the particular forms disclosed. On the contrary, the present disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. DETAILED DESCRIPTION

[0037] The micro device may be a micro LED, an OLED, a micro sensor, a MEM, or any other type of device.

[0038] The present invention is described below in connection with methods and structures for micro-device transfer.

[0039] In a related embodiment, a stage is formed on a donor substrate, and the microdevices are coupled to the stage via an adhesive or release layer. An anchor can temporarily secure the microdevices to the stage. The donor substrate can be aligned with an acceptor substrate, and a selected group of microdevices can be bonded to the acceptor substrate. The donor and acceptor substrates are removed, and the selected group of microdevices is transferred to the acceptor substrate. Here, the adhesive, release layer, or anchoring force is weaker than the bond between the microdevices and the acceptor substrate.

[0040] exist Figure 1A In another embodiment, shown in FIG, a mesa structure is developed on a donor substrate 110 as described above, wherein the microdevice structure is formed by etching through different layers, such as a first bottom conductive layer 112, a functional layer 114, such as a light-emitting layer, and a second top conductive layer 116. A top contact pad 132 may be deposited on top of the top conductive layer 116 before or after etching. Furthermore, each microdevice may include an additional passivation layer and / or MIS layer 172 surrounding each microdevice for isolation and / or protection. In this embodiment, the microdevice may be provided with different anchors, thereby securing the microdevice to the donor substrate 110 after the microdevice is peeled off. The peeling may be performed using a laser. In one example, only the microdevice is scanned by the laser. In one embodiment, a mask having openings for the microdevices only on the backside of the donor substrate 110 may be used to block the laser from irradiating other areas. The mask may be separate or part of the donor substrate 110. In another case, another substrate may be attached to the microdevice to secure the microdevice before the peeling process. In another case, a filler layer 174 , such as a dielectric, may be used between the micro devices.

[0041] In the first illustrated embodiment, layer 192 is provided to secure the microdevice to donor substrate 110. Layer 192 may be a separate layer or a portion of the layers of the microdevice that is not etched during the development of the mesa structure. In another embodiment, layer 192 may be a continuation of one of layers 172. In this case, layer 192 may be a metal or dielectric layer (SiN or SiO2, or other materials). In another embodiment, an anchor is developed as a separate structure comprising an extension 194, a void / gap 196, and / or a bridge 198. Here, a sacrificial layer is deposited and patterned to have the same shape as the void / gap 196. Next, an anchoring layer is deposited and patterned to form a bridge 198 and / or an extension 194. The sacrificial material may be removed later to create the void / gap 196. We may also avoid extension 194. Similar to the previous anchor 192, another anchor may be made of a different structural layer. In another embodiment, filler layer 174 acts as an anchor. In this case, the fill layer 174 may be etched or patterned or left as is.

[0042] Figure 1B The sample is shown after removing the fill layer 174 and / or etching the fill layer to create an anchor. In another case, after peeling, the adhesive strength of the bridge layer 198 is sufficient to hold the micro device in place and act as an anchor. The final micro device is located on the right side of the substrate 110. Here, after peeling, some residue may remain under the micro device, acting as an adhesive bridge layer 198.

[0043] Figure 1B Only one substrate 110 is shown for illustration purposes. We can use one or a combination of them in the substrate.

[0044] like Figure 1C , the anchors may cover at least part or the entire perimeter of the microdevice, or may be patterned to form arms 194 and 192. Any of these structures may be used for any of the anchor structures.

[0045] Figure 1D An example of transferring a microdevice to an acceptor substrate 190 is shown. Here, the microdevice is bonded to pads 182 or placed in a predefined area without any pads. Pressure or separation forces can release the anchors by breaking them. In another case, temperature can also be used to release the anchors. The viscosity of the layer between the microdevice peel and the donor substrate 110 can be increased by controlling the temperature to act as an anchor. Figure 1E The micro-device is shown after transfer to an acceptor substrate 190 and illustrates a possible release point 198-2 in the anchor.The anchor may also be connected directly to the donor substrate 110 or indirectly to the donor substrate 110 via other layers.

[0046] A microdevice on a donor substrate can be developed to have two contacts on the same side facing away from the donor substrate 110. In one case, the microdevice can be transferred directly from the donor substrate 110 to the acceptor substrate 190. Here, the contacts on the same side facing away from the donor substrate 110 can be directly bonded to the acceptor substrate pads 182. The microdevice can be tested in the donor 110 or in a cassette substrate. In another embodiment, the microdevice can first be transferred from the donor substrate 110 to a cassette substrate before being transferred to the acceptor substrate 190. Here, the contacts on the same side facing away from the donor substrate 110 will not be directly bonded to the acceptor substrate 190, that is, the acceptor substrate 190 does not need to have specific pads 182. In this case, a conductive layer is deposited and patterned to connect the contacts to appropriate connectors in the acceptor substrate 190.

[0047] In one embodiment, the micro device has a functional body and a contact element. The contact element can be an electrical, optical or mechanical contact element.

[0048] In the case of optoelectronic microdevices, the microdevice may have functional layers and charge-carrying layers. The charge-carrying layers (doped layers, ohmic elements, and contacts) transfer charge (holes) between the functional layers and contacts external to the microdevice. The functional layers can generate electromagnetic signals (e.g., light) or absorb electromagnetic signals.

[0049] The system substrate may contain pixels and pixel circuits, with each pixel controlling at least one microdevice. The pixel circuits may be made of electrodes, transistors, or other components. Transistors may be fabricated using thin-film technology, CMOS, or organic materials.

[0050] In one embodiment, Figure 2A , the micro devices (2020, 2040, 2060, 2080) are located on a substrate 2004, and a release layer (2024, 2044, 2064, 2084) covers at least a portion of the surface of the micro devices (2020, 2040, 2060, 2080) facing the substrate 2004. A buffer layer 2002 may be present between the substrate 2004 and the micro devices (2020, 2040, 2060, 2080). In one embodiment, at least one anchor (2026, 2046, 2066, 2086) secures the micro devices (2020, 2040, 2060, 2080) to the substrate or the buffer layer.

[0051] In one case, the anchor 2026 is formed as an extension of a layer covering at least a portion of the micro device 2020. Here, a portion of the anchor is not covered by the release layer 2024, thereby coupling the portion to the buffer layer or substrate layer.

[0052] In another related aspect, a gap 2048 exists between the extension layer forming the anchor 2046 and at least a portion of the micro device 2040 .

[0053] In another related case, the anchor 2066 is formed as a layer covering at least a portion of the surface of the micro device 2060 facing the substrate 2004 .

[0054] In another embodiment, the anchor 2086 is formed as part of the micro device 2080. Here, the release layer 2084 does not cover the portion of the surface of the micro device 2080 that faces the substrate 2004. Therefore, the uncovered portion 2086 can be coupled to the substrate or a buffer layer. Here, the buffer layer can be an adhesive, a polymer, or a metal.

[0055] After the release layer is deactivated or removed, as Figure 2B As shown in FIG, the micro devices (2020, 2040, 2060, 2080) are fixed to the substrate via anchors. The micro devices can now be transferred to the system substrate, such as Figures 1A to 1E As explained in .

[0056] The release layer can be deactivated optically, chemically, thermally or mechanically.

[0057] In the case of chemical deactivation or removal, portions of the release layer are exposed so that chemicals (eg, solvents, etchants, or other chemicals) can penetrate and remove the release layer.

[0058] In the case of an optical release layer, the substrate is transparent to specific wavelengths that deactivate the release layer.

[0059] Figures 2C to 2D A method of developing a micro device in preparation for transferring the micro device into a system substrate is described.

[0060] In one step, at least one microdevice 2080, 2060, 2040, 2020 is formed on a first substrate 2090. The microdevice may have a pad 2080-2 that allows electrical connection to the microdevice on the top side (the top side is the side away from the first substrate). The microdevice may be covered by a passivation layer 2080-4. In addition, the microdevice may be covered by a protective layer 2080-6, which protects the microdevice from subsequent steps (portions of the protective layer may be removed after the process is complete). In a related case (2040, 2020), portions of the passivation layers 2040-4 and 2020-4 may be patterned to form anchors 2046 and 2026. In one case, a void structure 2048 is formed below the anchor portion. A buffer layer 2092 may be present between the microdevice and the substrate.

[0061] The micro device is bonded to the second substrate 2100 using a bonding layer 2102 and a planarization layer 2102 (these two layers may be the same). Figure 2CAs shown in FIG, the first substrate 2090 and the buffer layer 2092 are removed from the micro device. Here, an anchor layer 2066 is deposited (which may be patterned at this stage). The anchor layer 2066 may be a dielectric or metal or other type of material. Figure 2D As shown in FIG, release layers 2024, 2044, 2064, and 2084 are deposited and patterned. The release layer extends from at least a portion of the micro device edge 2042. Anchor layer 2066 can be a combination of multiple layers or a single layer. Anchor layer 2066 can change under different conditions, such as temperature, electrical bias, or light, to propel the micro device forward. The micro device can also have pads on the bottom side and a passivation layer (which can be the same as the anchor layer).

[0062] like Figure 2A As shown in FIG. 2 , the micro device can be bonded to a third substrate 2004 and removed from the second substrate.

[0063] Remove the planarization and first bonding layers. If the anchors are not patterned, they can be patterned at this stage. In order to Figure 2B ) to protect the micro devices, which may be covered by a second protective layer. The second protective layer may be a photoresist.

[0064] To package microdevices close together and improve raw wafer utilization, anchor modifications are required. In one case, the anchor of a microdevice is offset from the anchor of its neighboring microdevice on the donor / cassette substrate to provide more space for anchor integration. In another related case, the anchor is formed on the sidewall of the stage. In another case, the stage and anchor structure are formed below the microdevice.

[0065] Figure 3A An exemplary case of offset anchors is shown. Microdevices 3110A and 3110C are adjacent to each other on a donor / cassette substrate. Anchors 3116A, B, C, and D, and 3114A, B, C, and D (the anchors are repeated for each microdevice 3110A, B, C, and D, and the numbering also includes anchor labels A, B, C, and D) are formed around the microdevices. A release layer 3112A is formed beneath microdevice 3110A (the microdevice and microdevice structure are repeated for each microdevice 3110A, B, C, and D, and the numbering also includes microdevice labels A, B, C, and D). Here, for example, anchors 3114B and 3116C are offset.

[0066] Figure 3BAnother example of an offset anchor is shown. Micro devices 3110A and 3110C are adjacent to each other. Anchors 3116A and 3114A are formed around the micro device. A release layer 3112 is formed beneath micro device 3110A (the micro device and micro device structure (anchor) are repeated for each micro device 3110A, B, C, and D, and the numbering also includes the micro device / anchor labels A, B, C, and D). Here, for example, anchors 3114A and 3116C are offset.

[0067] Figure 4A Another related example is presented in . Here, microdevice 3200 is formed on top of stage 3202. There is a release layer 3204 that couples microdevice 3200 to stage 3202. The release layer can be an adhesive. In another related embodiment, the release layer can be a multilayer comprising an adhesive. The adhesive layer can be deactivated using various factors, such as temperature, chemicals, electrical, electrical charge, etc. There can be other adhesive layers between microdevice 3200 and stage 3202. Stage 3202 can be a polymer, dielectric, or conductive. Anchor 3206 can be formed on portions of microdevice 3200 and stage 3202. The structure is located on substrate 3208. Anchor 3206 can cover portions of another surface of microdevice 3200. Anchor 3206 can cover portions of a surface of substrate 3208. Figure 4B exhibit Figure 4A A top view of the structure in .

[0068] In another related embodiment, the stage is formed on the microdevice. Here, a release layer is formed and patterned. Thereafter, the stage material is formed. The stage can be deposited using different techniques, such as printing, spraying, PECVD, electron beam sputtering, etc. The stage is then bonded to substrate 3208 and the microdevice is separated from the original substrate. In another related embodiment, the stage is formed on substrate 3208. The stage may include a release layer and an adhesive layer. The stage is bonded to the microdevice using different techniques, such as thermal compression. For all related embodiments, the anchor can be formed after the stage is coupled to the microdevice. Here, the anchor layer is deposited and patterned. The patterning can be stripping, photolithography, or etching (dry or wet).

[0069] Figure 5AAnother related example is presented in . Here, anchor 3304 is formed on top of first stage 3306 on substrate 3308, with a portion of the anchor attached to the substrate. First stage 3306 may include a release layer 3306 that separates at least a portion of anchor 3304 from substrate 3308. A second stage is formed on top of anchor surface 3302. The second stage can be composed of different layers and may include an adhesive, a dielectric, a metal, or a different material. In one related embodiment, microdevice 3300 is coupled to anchor structure 3304. Here, microdevice 3300 is coupled to anchor surface 3304 using second stage (e.g., adhesive or bonding agent) 3302. In another related embodiment, the second stage is formed on the microdevice and bonded to anchor surface 3304. Following these related embodiments, the microdevice is separated from the original substrate after being coupled to the anchor. The formation of the second stage (or at least a portion thereof) can be selective. Thus, a selective set of microdevices is coupled to the anchor surface. To enable transfer, the release layer is removed or deformed so that the micro device can be easily removed by destroying the anchors. Figure 5B exhibit Figure 5A A top view of an example.

[0070] Figure 5A Another related example is presented in . Here, anchor 3304 is formed on top of substrate 3308. Release layer 3306 can separate at least a portion of anchor 3304 from substrate 3308. Micro device 3300 is coupled to anchor structure 3304. Here, micro device 3300 is coupled to anchor 3304 using adhesive or bonding agent 3302. The release layer is removed or deformed to enable transfer, allowing the micro device to be easily removed by destroying the anchor. Figure 5B exhibit Figure 5A A top view of an example.

[0071] A kind of Figure 5A One method of forming the anchor is to form the anchor and release layer in substrate 3308 and then bond the micro device to the anchor structure using bonding layer 3302. In another method, the anchor and release layer are formed on the micro device and then the micro device with the structure is bonded to substrate 3308.

[0072] Figure 5C yes Figure 5A Here, it shows where the anchor 3304 and a major portion of the release layer 3306 are located below the micro device 3300. As a result, the micro devices can be packaged closer to each other.

[0073] exist Figure 5C In another related embodiment, at least a portion of a second stage is selectively formed. Here, a selected group of micro devices are transferred from the original substrate to a donor substrate 3308 having a stage.

[0074] exist Figure 5C In another related embodiment, the anchor is the same as the first stage.

[0075] Figure 6 A top view of another related embodiment is shown. After release layer 3406 is deposited on cartridge substrate 3408, opening 3412 is formed in release layer 3412. Anchor and diaphragm layer 3404 is deposited and patterned. At least a portion of diaphragm layer 3404 extends into release layer opening 3412. Anchor and diaphragm layer 3404 is deposited and patterned. At least a portion of diaphragm layer 3404 extends into release layer opening 3412. Bonding layer 3400 is formed and patterned on top of diaphragm layer 3404. A selected group of microdevices from a donor substrate are aligned with and bonded to the bonding layer. The donor substrate is removed, and the selected microdevices are retained on cartridge substrate 3408 via bonding pattern 3400. This process can be repeated, and additional microdevices can be aligned with and transferred to cartridge substrate 3408. The microdevices can be different microdevices from different donor substrates. Before transferring the micro devices to the system substrate, the release layer is removed or deformed to facilitate transfer. A selected group of micro devices coupled to the cartridge substrate 3408 via the bonding layer 3400 is aligned with the landing areas (or bonding pads) on the system substrate. The micro devices are bonded to the system substrate via the bonding pads. During the micro device-to-system substrate bonding process, or when the cartridge substrate is moved away from the system substrate after bonding, the selected group of micro devices is separated from the cartridge substrate 3408 by separating the anchor structure 3404 from the substrate.

[0076] exist Figures 5A to 6 The bonding layer can be formed on the microdevices on the membrane (or anchor) layer or the donor substrate. The bonding pattern can be formed only for a selected group of microdevices to be transferred to the cartridge substrate. In one embodiment, the bonding layer 3404 is unpatterned. After the microdevices are transferred to the cartridge substrate, the bonding layer is patterned on the microdevices or another layer covering the microdevices. As a result, the bonding layer self-aligns with the microdevices, eliminating alignment errors.

[0077] Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6 The substrate in Figures 2, 3, 4, and 5 (all figures extended) may have a stack of layers, such as a buffer layer. The anchors in Figures 2, 3, 4, and 5 (all figures extended) may be developed using any of the methods described in this document or other methods. The release layer may be a polymer, a dielectric, or a metal. The anchoring layer may be a dielectric, a polymer, or a metal. The bonding layer may be a pressure sensitive adhesive, a thermosetting adhesive, a photocurable adhesive, or a general polymer. The adhesive may be photodefinable for patterning or etched to produce a pattern. The adhesive layer may be larger or smaller than the microdevice. The etching may be dry or chemical etching.

[0078] Figure 7A Another related example of the invention described herein is shown. Figure 7A In the embodiment of the present invention, a smaller diaphragm structure / layer is formed on substrate 3508. The diaphragm is smaller than the surface of microdevice 3500 in one dimension, so at least two diaphragms fit under microdevice 3500. Therefore, less alignment will be required to bond microdevice 3500 to the diaphragm structure using bonding layer 3502. The alignment accuracy requirement decreases as the number of diaphragms per microdevice increases. An example of a diaphragm structure is formed by depositing a material layer 3504 on a patterned release layer 3506. The material and release layer can be dielectrics, metals, organics, or other combinations. In one case, the diaphragm is a dielectric layer and the release layer is a metal. Bonding layer 3502 is formed on the surface of microdevice 3500 or diaphragm 3504. The bonding layer can be a continuous layer, patterned to match the diaphragm pattern, or patterned to match the microdevice. In one case, after the microdevice is bonded to the diaphragm structure, the bonding layer is etched and removed from the excess area not covered by the microdevice.

[0079] Figure 7B Another example of a membrane structure for micro-device transfer is shown. Here, the process is similar to Figure 7A After the diaphragm layer 3504 is formed, the surface of the diaphragm is etched away, thereby leaving more pillar-shaped structures on the surface of the microdevice.

[0080] Figure 7C An example of patterning 3510 of a release layer 3506 on a substrate 3508 is shown. Here, the pattern can be staggered to have more membrane structures under each microdevice and to aid alignment accuracy. This pattern can be different for different shapes or orientations.

[0081] Figure 8 Related embodiments related to the formation of membrane-based microdevice transfer are shown. During step 3602, a box diaphragm is manufactured on a box substrate using one or more of the described embodiments or related embodiments. During the next step 3604, the box substrate is inspected and defective areas are identified. The inspection can be visual or use different optical techniques. Defects can be repaired using different technologies, such as laser, fused ion beam (FIB) and other process technologies. In step 3606, defective areas are identified and good areas for transfer are selected. Good areas can be identified based on the number or type of defects per area. The box substrate can have island areas of diaphragms. Each area can be filled with one or a smaller area of the same size in the microdevice substrate. The size of the island is also selected to be compatible with the system substrate array so as not to cause interference with existing microdevices on the system substrate or existing pads during transfer.

[0082] During another step 3612-(1:j), microdevices may be fabricated on the microdevice substrate. There may be more than one microdevice associated with the upper cassette structure. The microdevices are fabricated as regions that are the same size as, or a multiple of, the islands in the cassette substrate. The microdevices are inspected for defects and performance based on predefined parameters (step 3614-(1:j)). The microdevice regions are separated from the wafer, and each region is divided into different groups based on final product performance requirements (step 3616-(1:j)).

[0083] During step 3620, a microdevice area associated with a similar or a product is used to fill the good box island in the substrate. Good areas can be identified based on the number or type of defects in each area. Selective transfer can be performed by filling the part of the box area with the part of the microdevice in a zone, or all microdevices in the microdevice area are transferred to the box island. In both cases, an adhesive layer can be used to form a bond between the microdevice and the diaphragm layer in the box island. Different methods (such as laser, light, chemical, mechanical, thermal, etc.) are used to separate the selected microdevice bonded to the diaphragm from the zone substrate. This process can be repeated until the entire box island is filled with one or more different types of microdevices. The box can undergo different processes, such as removing the release layer, curing, modulation, etc. Before or after each step, an inspection step 3622 can be performed to identify process defects. In a related embodiment for removing the release layer, a protective layer covers the microdevice and only leaves a small opening for the chemical to etch away the release layer.

[0084] After final inspection, cassettes are assigned to different applications based on performance metrics and defect rates 3624. Defects may be repaired or removed from the cassette before transfer.

[0085] Figure 9A Exemplary process steps for filling the box islands are shown. Here, the microdevice area substrate 3702 is aligned with the area of good box islands in the box substrate 3712. Good areas can be identified based on the number or type of defects per area. The two substrates are brought close together so that the microdevice 3704 is bonded to the box diaphragm structure 3714 via a bonding material 3722. Here, heat, pressure, or light can be used to achieve bonding. There can be a release layer 3706 between the microdevice 3704 and the area substrate 3702. The release layer can be delaminated chemically, laser, thermally, or mechanically. Thus, a bonded microdevice is left on the diaphragm structure 3716. As shown in FIG. Figure 9B As shown, processing can continue for the remaining micro devices 3704 on the same region substrate 3702, or for the same or different micro devices on completely different region substrates. Figure 9C In a related embodiment shown in FIG, micro device 3704 is coupled to region substrate 3702 via patterned release layer 3706. This reduces the deposition of residues of the release layer on the cartridge substrate. In a related embodiment, we can form a bonding layer 3722 on the micro device. Figure 9D An embodiment is shown where the exposed areas are covered by a protective layer. In the case where the release layer 3706 is a laser release layer, this layer can protect the cartridge substrate from the laser. The protective layer 3708 can be on the top surface of the substrate 3702, or on the same surface to which the micro device is coupled.

[0086] Figure 10A Show the example of the box island 3802 that is shaped different from square or rectangle.In a related embodiment, box island 3802 can be circular or oval or other shape.Here, micro-device area 3804 is rectangular or square shape.In a related embodiment, box island 3802 is filled with the micro-device from district 3804, and each district 3804 transfers and is optimized to cover the most area of box island 3802 inside.This may cause mismatch between micro-device in each district, thereby influence the micro-device transfer from box island to system substrate.

[0087] Figure 10B The example of display area 3804 being aligned and using enough area 3804 to cover the entire surface of the box island 3802. The area outside these islands can have a dummy diaphragm structure to enable the excess area of these areas to be bonded to the box substrate. These micro devices can be removed before transferring the micro devices to the system substrate.

[0088] While particular embodiments and applications of the present invention have been shown and described, it will be understood that the invention is not limited to the precise construction and composition disclosed herein, and that various modifications, changes, and variations will be apparent from the foregoing description without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for integrating an anchor to fix a micro device to a substrate, the method comprising: forming at least two diaphragm layers on the substrate so that at least two diaphragm structures are adapted below the surface of the micro-device, wherein the diaphragm structures are smaller than the surface of the micro-device in at least one dimension; as well as The micro-device surface is bonded to the diaphragm structure using a bonding layer. 2 . The method of claim 1 , wherein the alignment accuracy requirement decreases as the number of membrane layers per microdevice increases. The method according to claim 1 , wherein the diaphragm layer is formed by depositing a material layer on a patterned release layer. The method of claim 3 , wherein the diaphragm layer is a dielectric layer and the patterned release layer is a metal. The method according to claim 1 , wherein the bonding layer is formed on the micro device or on a surface of the diaphragm. The method of claim 5 , wherein the bonding layer is a continuous layer, patterned to match a diaphragm pattern, or patterned to match the microdevice. 7 . The method of claim 6 , wherein after the micro device is bonded to the membrane layer, the bonding layer is etched and removed from excess areas not covered by the micro device. 8 . The method according to claim 1 , wherein after the diaphragm layer is formed, the surface of the diaphragm is etched away, thereby leaving more pillar-shaped structures on the surface of the micro device.

9. The method of claim 3, wherein the pattern is staggered to have more of the membrane layers under each microdevice.

10. A method for transferring a micro device by forming a diaphragm, the method comprising: fabricating a cartridge diaphragm on a cartridge substrate; inspecting said cassette substrate to identify defective areas prior to said transferring; as well as Good regions are identified based on the number or type of defects per region. The method of claim 10 , wherein the inspection is visual.

12. The method of claim 10, wherein the defect is repaired by one of a laser and a fused ion beam (FIB) process.

13. The method of claim 10, wherein the cartridge substrate has island regions of membrane, wherein each region is filled with one or more smaller or same size regions of the micro device substrate.

14. The method of claim 13, wherein the size of the island region is further selected to be compatible with a system substrate array so as not to cause interference with existing micro devices on the system substrate or existing pads during the transfer.

15. A method for manufacturing a micro-device on a micro-device substrate, the method comprising: Dividing regions having the same size as or a smaller multiple of the islands in the cassette substrate; Verify microdevice defects and performance based on predefined parameters; as well as The micro device regions are separated from the wafer, and each region is divided into different groups based on the final product performance requirements.

16. The method of claim 15 , wherein the zones associated with similar or one product are used to fill good box islands in the substrate, wherein transfer is performed selectively by filling portions of a box zone with portions of the microdevices in one zone, or all of the microdevices in the zone are transferred to a box island.

17. The method of claim 16, wherein the selected micro devices bonded to the membrane are separated from the region substrate using one of laser, light, chemical, mechanical, or thermal methods.

18. The method of claim 17, wherein the process is repeated until the entire island is filled with one or different types of micro devices.

19. The method of claim 18, wherein the cassette undergoes different processes of removing the release layer, curing, and conditioning, and wherein further before or after each step, an inspection step is performed to identify process defects.

20. The method of claim 17, wherein when the release layer is removed, a protective layer covers the micro device and leaves only small openings for a chemical to etch away the release layer.

21. The method of claim 18, wherein after final inspection, the cassettes are assigned to different applications based on performance metrics and defect rates.

22. The method of claim 21, wherein defects are repaired or removed from the cassette prior to the transferring.

23. A method for filling a box island, the method comprising: Aligning the micro-device region substrate with the good box island region in the box substrate; Bringing the two substrates closer together so that the micro device is bonded to the box diaphragm structure via the bonding material; as well as A release layer is provided between the micro device and the region substrate, wherein the release layer is delaminated by a chemical, laser, thermal, or mechanical process, thereby leaving the micro device bonded to the membrane structure.

24. The method of claim 23, wherein the process described above continues with the remaining micro devices on the same region substrate, or on a completely different region substrate with the same or different micro devices. 25 . The method of claim 23 , wherein the micro device is coupled to the zone substrate via a patterned release layer to reduce deposition of release layer residue on the cassette substrate. The method according to claim 25 , wherein a bonding layer is formed on the micro device.

27. The method of claim 23, wherein in the case where the release layer is a laser release layer, the exposed area is covered by a protective layer to protect the cartridge substrate from the laser, wherein further the protective layer is on the top surface of the substrate, or on the same surface to which the micro device is coupled.

28. The method according to claim 23, wherein the box island is circular or oval, and wherein further the micro device area is rectangular or square.

29. The method of claim 23, wherein the box islands are populated with micro devices from a zone, and each zone transfer is optimized to cover a majority of the area inside the box islands.

30. The method of claim 23, wherein zones are aligned and sufficient zones are used to cover the entire surface of the box island, wherein further the area outside the box island has a dummy diaphragm structure to enable excess area of the zone to be bonded to the box substrate, and wherein the microdevices are removed prior to the transferring.

31. A method for integrating an anchor to secure a micro device to a cartridge substrate, the method comprising: depositing a release layer on the cartridge substrate; forming an opening in the release layer; depositing and patterning anchor and diaphragm layers; extending the newest portion of the diaphragm layer to the release layer opening; as well as A bonding layer is formed and patterned on top of the diaphragm layer.

32. The method of claim 31, wherein a selected group of micro devices from a donor substrate are aligned with and bonded to the bonding layer, wherein further the donor substrate is removed and the selected micro devices are retained on the cassette substrate via a bonding pattern.

33. The method of claim 32, wherein the process is repeated and further micro devices are aligned and transferred to the cassette substrate.

34. The method of claim 32, wherein the micro devices are different devices from different donor substrates.

35. The method of claim 32, wherein before transferring the micro device into a system substrate, the release layer is removed or deformed to enable the transfer.

36. The method of claim 35, wherein a second set of selected micro devices coupled to the cassette substrate via the bonding layer are aligned with landing areas (or bonding pads) on the cassette substrate, and the micro devices are bonded to the system substrate via the bonding pads.

37. The method of claim 36, wherein the second group of selected micro devices are separated from the cassette substrate by separating an anchor structure from the cassette substrate during a bonding process of the micro devices to the system substrate or when the cassette substrate is moved away from the system substrate after bonding.

38. The method of claim 32, wherein the bonding layer is formed on the membrane (or anchor) layer or on the micro device on the donor substrate.

39. The method of claim 38, wherein the bonding pattern is formed only for a selected group of micro devices transferred to the cassette substrate.

40. The method of claim 32, wherein the bonding layer is unpatterned and after transferring the micro device to the cartridge substrate, the micro device or another layer covering the micro device is used to pattern the bonding layer.

41. A method for transferring a micro device, the method comprising: developing a mesa structure on a donor substrate wherein a microdevice structure is formed by etching through different layers, a first bottom conductive layer, a functional layer, and a second top conductive layer; depositing a top contact pad on top of the second top conductive layer before or after the etching, wherein the top contact pad is deposited on top of the second top conductive layer before or after the etching, and each micro device includes a passivation layer and / or MIS layer surrounding each micro device for isolation and / or protection; as well as The micro device is provided with different anchors, whereby the anchors secure the micro device to the donor substrate after the micro device is peeled off.

42. The method according to claim 41, wherein the lift-off is performed by laser, and a mask having openings for the micro devices only on the back side of the donor substrate is used to block the laser from irradiating other areas. The method according to claim 41 , wherein another substrate is connected to the micro device to fix the micro device before the peeling.

44. The method of claim 41, wherein a filler layer, such as a dielectric, is used between the micro devices.

45. The method of claim 41, wherein a first layer is provided to secure the micro device to the donor substrate, wherein the first layer is a separate layer or a portion of the layer of the micro device that is not etched during development of the mesa structure.

46. The method of claim 41, wherein the first layer is a continuation of the fill layer, wherein the first layer is a metal or dielectric layer.

47. A method according to claim 41, wherein the anchor is developed as a separate structure comprising an extension, a gap / void, and / or a bridge, wherein a further sacrificial layer is deposited and patterned having the same shape as the gap / void, and then the anchoring layer is deposited and patterned to form the bridge and / or the extension.

48. The method of claim 47, wherein the sacrificial material is removed to create the void / gap and also to avoid the extension.

49. The method of claim 41, wherein the fill layer acts as an anchor and is etched or patterned or left as is.

50. The method of claim 41, wherein after peeling, the adhesion of the bridging layer is sufficient to hold the micro device in place and act as an anchor.

51. The method of claim 41, wherein the anchors cover at least part or the entire perimeter of the micro-device, or are patterned to form arms for any anchor structure.

52. The method of claim 41, wherein the micro devices are transferred to an acceptor substrate and bonded to acceptor substrate pads, or placed in a predefined area without any pads, and wherein further pressure or separation force releases them by breaking the anchors.

53. A method according to claim 41, wherein the microdevice is transferred to a receptor substrate and bonded to the pads, or placed in a predefined area without any pads, and wherein further temperature is used to release the anchor, and the viscosity of the layer between the peeled-off microdevice and the donor substrate is increased by controlling the temperature to act as an anchor.

54. The method of claim 41, wherein the micro device on a donor substrate is developed to have two contacts on the same side facing away from the donor substrate.

55. The method of claim 54, wherein the micro device is transferred directly from the donor substrate to the acceptor substrate, and the contacts on the same side facing away from the donor substrate are directly bonded to the acceptor substrate pads.

56. A method according to claim 41, wherein the microdevice is first transferred from the donor substrate to a box substrate before being transferred to the acceptor substrate, and wherein the contacts on the same side facing away from the donor substrate are not directly bonded to the acceptor substrate 190, and wherein a further conductive layer is deposited and patterned to connect the contacts to appropriate connectors in the acceptor substrate.

57. The method of claim 52, wherein after the transferring, the micro device is on the acceptor substrate, wherein a release layer covers at least a portion of a surface of the micro device facing the acceptor substrate, wherein a buffer layer is between the acceptor substrate and the micro device.

58. The method of claim 57, wherein at least one anchor secures each micro device to the receptor substrate or the buffer layer.

59. The method of claim 58, wherein the anchor is formed as an extension of a layer covering at least a portion of the micro device, wherein further a portion of the anchor is not covered by the release layer, thereby coupling to the buffer or the receptor substrate.

60. The method of claim 59, wherein a gap exists between an extension layer forming the anchor and at least a portion of the micro device.

61. The method of claim 59, wherein one of the anchors is formed as a layer covering at least a portion of the micro device surface facing the receptor substrate.

62. A method according to claim 59, wherein one of the anchors is formed as part of one of the microdevices, wherein the release layer does not cover the portion of the surface of the microdevice facing the receptor substrate, so that the uncovered portion is coupled to the receptor substrate or the buffer layer, wherein the buffer layer is an adhesive, a polymer, or a metal.

63. The method of claim 58, wherein the release layer is deactivated or removed optically, chemically, thermally, or mechanically, wherein further in the case of chemical deactivation or removal, a portion of the release layer is exposed to allow a chemical to penetrate and remove the release layer.

64. The method of claim 63, wherein in the case of an optical release layer, the receptor substrate is transparent to a specific wavelength that deactivates the release layer.

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