Method and apparatus for depositing components onto a target surface of a target, and donor plate for use therewith

Abstract

Disclosed herein is a deposition apparatus (1) for depositing components (Ca, Cb,...) on a target surface (TS) of a target (T), the deposition apparatus comprising a donor plate (3), at least one heater element (33), a power supply (6), a target manipulation device, and a controller (5) configured to control the power supply (6) and the target manipulation device (2; 21, 22). The controller causes the power supply (6) to supply at least a first pulse (Pulse 1) of power to at least one heater element (33) in a zone (32) to heat a donor plate surface (31s) in at least a first subzone (32a) of that zone to a surface temperature that exceeds a threshold temperature of an adhesive (7a) in said first subzone (32a). Following a change in the lateral position of the target (T) relative to the donor plate (3), the controller causes the power supply (6) to supply at least a second power pulse (Pulse 2) to the heater element to heat the donor plate surface (31s) in at least a second sub-zone (32b) to a surface temperature above the threshold temperature of the adhesive (7b) in said second sub-zone (32b), thereby allowing components in zones sharing the same heater element to be transported independently of each other.

Description

[Technical Field]

[0001] The present invention relates to a method for depositing components onto a target surface of a target.

[0002] The present invention further relates to an apparatus for depositing components onto a target surface of a target.

[0003] The present invention further relates to donor plates for use with the apparatus and / or methods. [Background technology]

[0004] U.S. Patent Application Publication No. 2020168498 discloses a method for transferring multiple separate components from a first substrate to a second substrate. The method includes illuminating multiple regions on an upper surface of a dynamic release layer that bonds the multiple separate components to the first substrate. The illumination induces plastic deformation in each of the irradiated regions of the dynamic release layer. The plastic deformation simultaneously releases at least some of the separate components from the first substrate.

[0005] A drawback of known approaches is that the resolution at which the transfer of components can be independently controlled is limited by the resolution at which the dynamic release layer can be heated.

[0006] Therefore, there is a need to provide an improved approach that allows for the controllable transport of components with a resolution higher than that determined by the resolution at which heat is applied. Summary of the Invention

[0007] According to a first aspect of the present disclosure, a novel deposition apparatus is provided that is improved in that it allows for controlled transfer of components from a donor plate to a target with a resolution greater than that determined by the resolution at which heat is applied to the donor plate.

[0008] According to a second aspect of the present disclosure, a novel deposition method is provided that is improved in that it allows for the controlled transfer of components from a donor plate to a target with a resolution higher than that determined by the resolution at which heat is applied to the donor plate.

[0009] An embodiment of the improved deposition apparatus comprises a donor plate, at least one heater element, a power supply, a target manipulation device, and a controller.

[0010] At least one heater element is provided to heat the donor plate surface of the donor plate in at least one zone. In one example, the heater element is a flash light or a laser so that the heater element heats the at least one zone by optical radiation directed at the zone. In another example, the heater element is a resistive heater layer disposed below the donor plate surface of the donor plate in at least one zone.

[0011] The donor plate surface is configured to temporarily bond respective components in respective sub-zones of the at least one zone with respective adhesives that evaporate when the temperature of the donor surface in each sub-zone exceeds a threshold temperature for the adhesive.

[0012] The power supply is configured to controllably supply pulses of power to at least one heater element to heat the donor plate surface in at least one zone.

[0013] The target manipulation device is configured to laterally position the target relative to the donor plate while holding the target with the target surface facing the donor plate surface. In one example, the target manipulation device laterally positions a target carrier carrying the target while holding the donor plate in a fixed position. In another example, the target manipulation device laterally positions the donor plate with the target in a fixed lateral position. In yet another example, the target manipulation device laterally positions the donor plate and the target.

[0014] The controller is configured to control the power supply and the target manipulation device. The controller has a first operating state in which the power supply supplies at least a first power pulse to at least one heater element to heat the donor plate surface in at least a first subzone to a surface temperature that exceeds a threshold temperature of the adhesive layer in the first subzone. The controller has a second operating state in which the target manipulation device changes a lateral position of the target relative to the donor plate. The controller further has a third operating state in which the power supply supplies at least a second power pulse to at least one heater element to heat the donor plate surface in at least a second subzone to a surface temperature that exceeds a threshold temperature of the adhesive sample in the second subzone.

[0015] Although the heater elements in both the first and third operating states heat the same zone, this does not cause simultaneous transport of components within various sub-zones of that zone.

[0016] Typically, at least one zone is divided into a number of subzones substantially greater than two, for example 16. The controller is then configured to provide a corresponding number of pulses such that, at each pulse, the surface temperature exceeds a threshold temperature of the respective adhesive that bonds the respective components of each subzone and, therewith, induces vapor pressure by evaporation of the respective adhesive that causes transport of the respective components.

[0017] The second pulse may have a longer duration and / or a greater power than the first pulse. Similarly, if the zone includes three or more subzones, each subsequent pulse again has a longer duration and / or a greater power.

[0018] The donor plate may comprise multiple zones, each of which may be divided into sub-zones. In one embodiment, each zone has an appropriate resistive heating element. In another embodiment, where optical radiation is used as the heat source, a single optical radiation source, e.g., a laser, is used that is selectively directed at the various zones.

[0019] In one embodiment of the deposition apparatus, the donor plate includes a thermal buffer layer in at least one second subzone between at least one heater element and the donor plate surface. The thermal buffer layer in the second subzone reduces the heat flux from the at least one heater element to the donor surface in the second subzone so that the surface temperature as a function of time in the second subzone lags behind the surface temperature as a function of time in the first subzone. In this embodiment, the same adhesive can be used for each adhesive layer bonding the respective components in each subzone. In a first operating state, the surface temperature in the first subzone exceeds the adhesive's threshold temperature, resulting in transfer of the components in the first subzone. However, the surface temperature in the second subzone remains below the threshold temperature so that the components in that subzone remain bonded. In a second operating state, pulses with longer duration and / or higher power cause the surface temperature in the second subzone to also exceed the adhesive's threshold temperature, resulting in transfer of the components in the second subzone. In the first sub-zone, the thermal buffer layer may be thinner than the thermal buffer layer in the second sub-zone. Alternatively or additionally, different materials can be used for the thermal buffer layer in each sub-zone to control the conduction of heat from the heater element to the donor plate surface.

[0020] In another embodiment, the adhesive bonding components in the second subzone of the donor surface has a higher threshold temperature than the adhesive bonding components in the first subzone of the donor surface, and in this embodiment, a patterned thermal buffer layer is not required.

[0021] In a first operating state of the controller, the surface temperature in the first subzone exceeds the adhesive threshold temperature of the adhesive layer present therein, resulting in component transfer within the first subzone. However, the surface temperature in the second subzone remains below the higher adhesive threshold temperature of the sample in the second subzone, resulting in the components in that subzone remaining bonded. In a second operating state, pulses of longer duration and / or greater power cause the surface temperature in the second subzone to also exceed the higher adhesive threshold temperature used in that second subzone, resulting in component transfer within the second subzone.

[0022] It should be noted that aspects of the latter two embodiments can be combined, i.e., the patterned thermal buffer layer can be provided in zones, and different sub-zones can have different adhesives.

[0023] One way to alter the threshold temperature of an adhesive is to use a photoacid generator, such as TAG or PAG, added to it. Prior to placing components on a donor plate, a coating of adhesive material with one or more of these additives can be exposed to different curing conditions, for example, by exposing it to light radiation of different intensities and / or durations to control the decomposition temperature per subzone within the zone. Other additives can also be used, but patterning can be difficult. An example of tuning polymer decomposition is described in Phillips et al., "Polymer Degradation and Stability," in Science Direct, Volume 125, March 2016, Pages 129-139.

[0024] An embodiment of an improved method for depositing components onto a target surface of a target includes the following steps.

[0025] Providing the donor plate with at least one heater element for heating a donor plate surface of the donor plate in at least one zone of the donor plate.

[0026] When the temperature of the donor plate surface of each subzone exceeds a threshold temperature of the adhesive layer, the adhesive layer adhering the components of each subzone evaporates, adhering the respective adhesive layer to the donor surface of each subzone of at least one zone, together with the respective adhesive layer.

[0027] The target is positioned with its surface facing the donor plate surface of the donor plate.

[0028] At least a first pulse of power is supplied to at least one heater element to heat the donor surface, wherein the temperature of the donor plate surface in at least a first one of the subzones is at a value that is at least a threshold temperature of an adhesive type that bonds a first component in the first one of the subzones to eject the first component, and the temperature of the donor surface in at least a second one of the subzones is at a value that does not exceed a threshold temperature of an adhesive type that bonds a component in the second one of the subzones.

[0029] The target is translated laterally relative to the donor plate.

[0030] At least a second pulse of power is supplied to at least one heater element to heat the donor surface, and the temperature of the donor surface in a second one of the subzones assumes a value that is at least a threshold temperature of an adhesive type that bonds components in the second one of the subzones together with ejecting the components in the second one of the subzones toward a target.

[0031] In one embodiment of the method, the donor plate comprises a thermal buffer layer between the at least one heater element and the donor plate surface.

[0032] In an alternative embodiment, or in combination with the preceding embodiment, the components in the second sub-zone of the donor surface are bonded with an adhesive having a threshold temperature higher than the threshold temperature of the adhesive bonding the components in the first sub-zone of the donor surface.

[0033] The adhesive layer, with a thickness in the range of 0.1 μm to 10 μm, also functions as a thermal insulator to ensure that the components remaining on the donor plate remain relatively cool. Typically, the thickness is selected in the range of 1 μm to 5 μm.

[0034] In some embodiments, a temporary carrier is used to adhere the components to a donor plate before transferring them to the target. Here, the temporary carrier with the adhered components is pressed against a donor plate surface provided with an adhesive material. The temporary carrier is then removed, leaving the components adhered to the adhesive on the surface of the donor plate. In one example, the components are relatively weakly adhered to the temporary carrier, so that the relatively strong adhesive force exerted by the adhesive material on the donor plate allows the components to remain on the donor plate. In another example, the temporary carrier is a photosensitive release tape. After the tape with the components is pressed against the adhesive on the donor plate, the adhesion of the components to the photosensitive release tape is reduced by irradiating the photosensitive release tape with light radiation. In this case, it is not necessary to use a weak adhesive for the temporary carrier.

[0035] In one embodiment of the improved method, the adhesive material provided on the surface of the donor plate is a positive photoresist. Following attachment of each component, UV radiation is directed toward the side of the donor plate having the components attached thereto, exposing portions of the positive resist present between the components to the UV radiation, and then removing the exposed portions of the positive resist. This avoids shear forces between adjacent components when one of the adjacent components is transferred.

[0036] In yet another embodiment that can be combined with any of the preceding embodiments, the donor plate surface is divided into different subzones having spacer pillars of different heights. An adhesive is provided between the pillars in the subzones at a height greater than the height of the pillars. Each component is then pressed against the pillars in the respective zone, thereby contacting the component with the adhesive layer and adhering the component to the donor plate surface. The volume of the adhesive sample in each subzone is preferably smaller than the volume defined between the pillars in the respective subzone. This prevents the adhesive layer from contacting the pillars when the component is pressed against them. This prevents shear forces from occurring during component transfer to the target. An example of an embodiment for providing the adhesive sample includes uniformly depositing an adhesive or a precursor thereof on the donor plate surface having spacer pillars to a height greater than the height of the highest spacer pillar. The pillar height controls the heat sink effect on the component located thereon. The lower the pillar height, the stronger the heat dissipation effect. Thereby, when heating the zone, it is achieved that the temperature of the surface in the subzone between the lower pillars remains lower than the temperature of the subzone between the upper pillars, which makes it possible to exceed a single predetermined threshold temperature in successive subzones with successively higher pillars by generating heating pulses of successively increasing duration and / or power.

[0037] In one example of this embodiment, the adhesive used is a photoresist containing a photoacid generator. The threshold temperature of the adhesive can be changed to different values ​​in different subzones by activating the photoacid generator to different degrees, as determined by the duration or intensity of irradiation with optical radiation (e.g., UV radiation). In this case, the pillars do not need to have different heights. However, the two approaches can be combined in that, on the one hand, the temperature distribution within the region is determined by the height of the pillars, and, in addition, the adhesive in different subzones is provided with its respective threshold temperature by activating the photoacid generator therein to different degrees. If the adhesive material is a positive photoresist, each portion within each subzone is selectively hardened, and unhardened material is removed. The volume of the hardened portion in each subzone must be smaller than the volume enclosed by the pillars of the subzone. This is to avoid the remaining portion coming into contact with the pillars when compressed by the components supported by the pillars. As mentioned above, the photoresist in each subzone can have different threshold temperatures as a result of being activated to different degrees.

[0038] Note that this process is possible with negative photoresist, but is more difficult. In that case, the adhesive for the components needs to be crosslinked to remove excess uncured material, which makes it difficult to apply different degrees of cure to different adhesive patches. Also, curing negative resists typically makes it difficult to melt / reflow the resist.

[0039] The present disclosure further provides an improved donor plate for use in a deposition apparatus or method, the improved donor plate including at least one heater element for heating a donor plate surface in at least one zone, the donor plate surface configured to temporarily bond respective components with respective adhesives in respective sub-zones of the at least one zone, the adhesive bonding the components in each sub-zone evaporating when the temperature of the donor surface in each sub-zone exceeds a threshold temperature of the adhesive, and wherein the donor plate includes a thermal buffer layer between the at least one heater element and the donor plate surface in at least one second sub-zone.

[0040] These and other aspects of the disclosure will be described in more detail with respect to the drawings. [Brief explanation of the drawings]

[0041] [Figure 1] FIG. 12 shows a schematic representation of an embodiment of an improved deposition apparatus for depositing components onto a target surface of a target T. [Figure 2] FIG. 2 shows a schematic representation of an embodiment of an improved deposition apparatus for depositing components on a target surface of a target T, with FIG. 2 showing further details of the components, the upper part of FIG. 2 showing a top view according to II in FIG. 1, the middle part of FIG. 2 showing one zone thereof in more detail, and the lower part of FIG. 2 showing a cross section of this zone according to II-II in the middle part of FIG. 2. [Figure 3] FIG. 3 illustrates the operation of the improved deposition apparatus, with the control aspects shown schematically in the upper part of FIG. 3 and the corresponding physical aspects shown in the lower part of FIG. [Figure 4a] FIG. 4a shows a simulation aspect of an embodiment of the improved method, showing the simulated temperature curve as a function of time. [Figure 4b]FIG. 4b shows a simulation aspect of an embodiment of the improved method, showing the pulse time required to achieve a given surface temperature as a function of the physical dimensions of the part. [Figure 4c] FIG. 4c shows a simulation aspect of an embodiment of the improved method, showing the fluence required to achieve a given surface temperature as a function of the physical dimension. [Figure 4d] FIG. 4d shows a simulation aspect of an embodiment of the improved method, illustrating the physics of the model used in the simulation. [Figure 5A] FIG. 5A illustrates aspects of the first embodiment of the method in more detail. [Figure 5B] FIG. 5B illustrates aspects of the first embodiment of the method in more detail. [Figure 5C] FIG. 5C illustrates aspects of the first embodiment of the method in more detail. [Figure 5D] FIG. 5D illustrates aspects of the first embodiment of the method in more detail. [Figure 5E] FIG. 5E illustrates aspects of the first embodiment of the method in more detail. [Figure 5F] FIG. 5F illustrates aspects of the first embodiment of the method in more detail. [Figure 5G] FIG. 5G illustrates aspects of the first embodiment of the method in more detail. [Figure 5H] FIG. 5H illustrates aspects of the first embodiment of the method in more detail. [Figure 5I] FIG. 5I illustrates aspects of the first embodiment of the method in more detail. [Figure 6A] FIG. 6A shows aspects of another embodiment. [Figure 6B] FIG. 6B shows aspects of another embodiment. [Figure 6C] FIG. 6C shows aspects of another embodiment. [Figure 7A] FIG. 7A shows yet another embodiment. [Figure 7B] FIG. 7B shows yet another embodiment. [Figure 7C]FIG. 7C shows yet another embodiment. [Figure 7D] FIG. 7D shows yet another embodiment. [Figure 8A] FIG. 8A shows components of a further embodiment of a deposition apparatus. [Figure 8B] FIG. 8B shows components of a further embodiment of a deposition apparatus. [Figure 8C] FIG. 8C illustrates operations performed by the further embodiment. [Figure 9] FIG. 9 shows a further application of an embodiment of the deposition apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0042] Like reference symbols in the various drawings indicate like elements unless otherwise indicated.

[0043] 1 and 2 schematically illustrate an embodiment of an improved deposition apparatus 1 for depositing components Ca, Cb, . . . on a target surface TS of a target T. As shown in FIG. 1, the deposition apparatus includes a donor plate 3 having a donor plate surface 31s, an output 6, target manipulation devices 2, 21, 22, and a controller 5 configured to control the output 6 and the target manipulation device 2.

[0044] The upper part of Figure 2 shows the donor plate surface 31s in a top view according to II in Figure 1. The central part of Figure 2 shows one zone 32 of the donor plate 3. The lower part of Figure 2 shows a cross section of this zone according to II-II in the central part of Figure 2.

[0045] The power supply 6 is configured to controllably supply pulses of power to the heater elements 33 to heat the donor plate surface 31s within the zones 32. As shown in the top of Figure 2, the donor plate 3 comprises a plurality of zones 32_1, ..., 32_n, one of which is zone 32 shown in the middle and bottom of Figure 2, also shown as at least one zone.

[0046] As shown in FIG. 1, the target manipulation device 2 (21, 22) is configured to hold the target T with the target surface TS facing the donor plate surface 31s, and position the target T laterally relative to the donor plate 3.

[0047] The control unit 5 controls the power supply 6 and the target operation devices 2, 21, and 22.

[0048] The donor plate surface 31s is configured to temporarily bond respective components with respective adhesives in respective subzones of at least one of the zones 32. The adhesives provided to bond the components in each subzone are characterized by a threshold temperature, and the adhesive layer in the subzone evaporates when its temperature exceeds the threshold temperature.

[0049] The controller 5 is configured to have a succession of operating states, including at least a first operating state, a second operating state, and a third operating state. The operation of the controller 5 is shown schematically in the upper part of Figure 3. The lower part of Figure 3 shows the corresponding states of the donor plate.

[0050] In the first operating state S51, the controller 5 causes the power supply 6 to supply power to the heater element 33 in at least a first pulse (Pulse 1) to heat the donor plate surface 31s in at least the first subzone 32a to a surface temperature (Ta) that exceeds the threshold temperature (Tth) of the adhesive layer 7a in the first subzone 32a. As a result, the adhesive layer 7a, or a portion thereof, evaporates, and the resulting vapor pressure causes the component (Ca) to transport toward the target surface. The remainder of the zone 32 is also heated. However, as shown in the lower portion of FIG. 2 and the lower portion of FIG. 3, subzone 32a is the only subzone of zone 32 that does not have a thermal buffer layer. The other subzones 32b, 32c, 32d, etc. all have thermal buffer layers 34b, 34c, 34d, etc. Furthermore, the thicknesses of the thermal buffer layers in the other subzones are different from each other. For example, the thickness of thermal buffer layer 34c is greater than the thickness of thermal buffer layer 34b, and the thickness of thermal buffer layer 34d is greater than the thickness of thermal buffer layer 34c, so that the temperatures of the other subzones remain below the threshold temperature of the adhesive layer bonding the components therein.

[0051] In a second operating state S52, the controller causes the target manipulation device 2 to change the lateral position of the target T relative to the donor plate 3.

[0052] Then, in a third operating state S53, the controller causes the power supply 6 to supply at least a second pulse, Pulse 2, of power to the heater element to heat the donor plate surface 31s in subzone 32b to a surface temperature that exceeds the threshold temperature of the adhesive 7b in the second subzone 32b. As shown at the top of FIG. 3, the duration of the second pulse, Pulse 2, is longer than the duration of the first pulse, Pulse 1, so that the surface temperature Tb in the second subzone 32b exceeds the threshold temperature Tth, and component Cb is transferred to the target. Due to the fact that components Ca and Cb are transferred at different times from each other and that the lateral position of target T relative to donor plate 3 is changed during second operating state S52, components Ca and Cb can have relative positions relative to each other on the target, independent of their relative positions on the donor plate. Similarly, components Cc and Cd can be deposited at any selected location on the target by sequentially delivering a third pulse, Pulse 3, in operating state S55 and a fourth pulse, Pulse 4, in operating state S57, where each subsequent pulse is of longer duration than the previous pulse, by laterally moving target T relative to donor plate 3 between subsequent pulses in operating states S54 and S56. This can be extended to the independent transfer of a larger number of components, with each subsequent pulse having increasing pulse duration and / or pulse power, if the zones comprise a corresponding number of subzones with buffer layer thicknesses that differ from each other. In the example shown in the central portion of Figure 2, zone 32 includes 16 subzones with buffer layer thicknesses that differ from each other. The thicknesses of the buffer layers within the subzones are indicated schematically by their shading. Darker shading indicates thicker buffer layers. Note that the spatial thickness distribution may be provided in a pattern other than that shown in Figure 2 if the subzones within a zone have buffer layer thicknesses that differ from each other. The thickness of the thermal buffer layer is selected, for example, from the range of 0 μm to 2 μm, i.e., the thickness of the thermal buffer layer in the subzone having the component that must be deposited first may have a value of 0 μm, and the thickness of the thermal buffer layer in the subzone having the component that must be deposited last may have a value of 2 μm.The thermal buffer material is, for example, a ceramic material such as SiO2. By providing each subzone with a thermal buffer layer having a different thickness within this range, different heating delays can be achieved that are best suited to the actual purpose. Alternatively or additionally, it may be possible to use buffer layers with different compositions in different subzones. However, for practical purposes, it is preferable to use buffer layers with different thicknesses.

[0053] Figures 4(a)-4(d) show simulations of this method. As shown in Figure 4(d), a donor plate 3 is modeled to include a stack built on a silicon wafer 30 with a thickness of 675 μm. The stack includes, in order, a thermal and electrical insulating layer 36 with a thickness of 1 μm, a resistive heater layer 33 formed of Mo with a thickness of 0.13 μm, an electrical insulating layer 35 of SiN with a thickness of 0.5 μm, and a thermal buffer layer 34 of SiO2. The effect of the thickness of the thermal buffer layer on the heat flux at the donor surface was investigated. In these simulations, the thickness of the thermal buffer layer 34 was varied from 0 to 1 μm.

[0054] The model used for the simulation further includes component C being adhered to surface 31s of donor plate 3 with an adhesive that acts as a propellant P. The modeled adhesive layer P has a thickness of 3 μm. The modeled properties of the adhesive are a thermal conductivity coefficient λ=0.2 W / mK, a density ρ=1200 kg / m3, and a heat capacity C=1500 J / kgK. These are typical values ​​for photoresists such as SU-8 and other photoresist materials, and the modeled component C has a thickness of 50 μm.

[0055] FIG. 4(a) shows a curve illustrating the simulated temperature at the interface 31s between the adhesive P and the thermal buffer layer 34 as a function of time for the surface 31s of the donor plate 3, depending on the thickness of the thermal buffer layer 34, when a heat flux of 75 kW / cm2 is applied to the heater layer 33 at 10 μs intervals. In FIG. 4(a), it can be seen that the time t1 at which the surface 31s reaches the threshold temperature Tth in the presence of a 1 μm-thick SiO2 layer 34 is approximately 4 μs later than the time t0 in the absence of the thermal buffer layer. This allows the surface 31s to be heated to the threshold temperature Tth while preventing the surface 31s in other subsections with a thermal buffer layer from reaching the threshold temperature Tth by interrupting the heating pulse in a timely manner. More generally, the temperature of the surface can be heated to the threshold temperature in subsections with a thermal buffer layer less than a predetermined thickness, or in subsections with no thermal buffer layer at all. By interrupting the heating pulse in a timely manner, the temperature of the surface can be prevented from reaching the threshold temperature in subsections with a thermal buffer layer having a thickness greater than a predetermined thickness.

[0056] 4(a) also shows the simulated temperature curve of the resistive heater layer 33. It was found that the resistive heater layer 33 did not exceed a temperature of about 600°C.

[0057] The simulation further shows that component C, modeled here as a silicon chip with a thickness of 50 μm, barely heats up, as shown by line TC. This is achieved by the adhesive layer P having a low thermal conductivity. When using a spacer structure, on the order of 1 μm or less, the component's heat sink begins to affect the temperature profile at the interface 31s of the adhesive P and the thermal buffer layer 34, as shown in FIGS. 7A-7D.

[0058] FIG. 4( b ) shows the pulse time required to achieve a temperature of the surface 31 s of the donor plate 3 above the threshold temperature Tth of 300° C. depending on the thickness of the thermal buffer layer 34 .

[0059] Fluctuations in fluence and heat flux are typically + / - 1% or more, so threshold-based transfer is possible when using variable thicknesses of the thermal buffer layer 34 in the range of 0-2 μm.

[0060] FIG. 4( c ) shows the fluence required to achieve a temperature of the surface 31 s of the donor plate 3 exceeding the threshold temperature T th of 300° C. depending on the thickness of the thermal buffer layer 34 .

[0061] As can be seen in Figures 4(b) and 4(c), the curves are slightly offset from each other because the simulation accounts for temperature-dependent material properties, including the thermal conductivity of silicon and the change in resistance of molybdenum (positive temperature coefficient of resistance).

[0062] As mentioned above, the simulation is performed with a simulated heat flux of 75 kW / cm². To shorten the time required to implement this method, a higher heat flux can be used instead. For example, when the heat flux induced by the resistive heater layer 33 is set to 150 kW / cm², the release time, i.e., the time to reach the threshold temperature Tth at the surface, is approximately 1 µs and approximately 3 µs in the absence of a thermal buffer layer and the presence of a 1 µm SiO² thermal buffer layer 34, respectively. Despite the high heat flux values, the total amount of energy required to reach the threshold temperature is less due to the short pulse length. For example, assuming a threshold temperature of 300°C and generating a heat flux of 75 kW / cm² with the heater element, the donor plate surface reaches the threshold temperature after only 4 µs when a 1 µm thick SiO² layer is applied. When a higher heat flux of 150 kW / cm² is applied, less energy is required to reach the threshold and the pulse length is shorter. Applying a 1 μm SiO2 layer increased the release time from 1 to 3 μs.

[0063] 5A-5I illustrate aspects of the first embodiment of the method in more detail.

[0064] FIG. 5A shows a cross-section of a donor plate 3 having a donor surface 31s on a first side 31. A heater element 33 is provided in a zone 32 of the donor plate 3. In the illustrated example, the heater element is formed by a resistive heater layer extending over the entire area of ​​the donor plate 3. The resistive heater layer 33 can be heated locally, i.e., within the zone 32, by applying electrical power between a first electrical contact 37, 37′, designated as an anode, and an electrical contact 38, designated as a cathode. FIG. 5A also shows an electrical insulating layer 35 on the resistive heater layer 33. A preparation step involves providing a patterned thermal buffer layer 34 that defines the division of the zone 32 into subzones 32a, 32b, 32c, and 32d, each having a respective portion of the patterned thermal buffer layer 34. In one embodiment of the method, the patterned thermal buffer layer 34 is provided by depositing a uniform layer of thermally insulating material, such as a ceramic material, e.g., SiO / SiN, which is then etched in the desired pattern to define the subzones 32a, 32b, 32c, and 32d. The deposition is performed, for example, by a CVD process, such as PECVD, e.g., using an evaporation method. In an alternative embodiment, the patterned thermal buffer layer 34 is provided in a single step, e.g., using a patterned deposition method using a deposition mask.

[0065] 5B shows a subsequent step in which a layer P of propellant is deposited, for example by slot-die coating or spin-coating. In the example shown, the propellant is an adhesive, here a (positive) photoresist.

[0066] 5C shows a subsequent step in which the components Ca, Cb, Cc, Cd,... are transferred from the temporary carrier TC to the surface 31s coated with the propellant P. In one example, the temporary carrier TC is a UV release tape. In this example, the temporary carrier TC with the components Ca, Cb, Cc, Cd,... is subjected to a pressure PR against the layer P of adhesive propellant on the surface 31s.

[0067] 5D shows a subsequent step in which the temporary carrier TC is irradiated with UV radiation UV1. Subsequently, the temporary carrier TC is removed, leaving the components Ca, Cb, Cc, Cd,... adhered to the surface 31s of the donor plate 3.

[0068] In a subsequent step shown in FIG. 5E, the donor plate 3 having the components Ca, Cb, Cc, Cd,... attached to its surface 31s is exposed to UV radiation UV2 coming from the first side 31 of the donor plate 3. Portions Pi of the positive photoresist forming the layer P of propellant present between the components Ca, Cb, Cc, Cd,... are developed and then removed (see FIG. 5F), thereby avoiding shear forces between adjacent chips.

[0069] As shown in Figure 5F, a prepared donor plate 3 is obtained, in which Ca, Cb, Cc, Cd, ... are adhered to the surface 31s of the patterned thermal buffer layer 34 but not to each other.

[0070] 5G shows that the donor plate 3 prepared in the preceding step is positioned by the support unit 4 with its first main surface 31 facing the surface TS of the target T. In the illustrated example, the support unit 4 comprises a cooling chuck 43 in thermal contact with a second main surface 31s opposite the main surface 31s of the donor plate. The cooling chuck 43 comprises an exhaust channel 431 that is exhausted to clamp the donor plate 3 against the cooling chuck 43 of the support unit by an environmental pressure that is relatively high compared to the pressure in the exhaust channel. In the illustrated example, the exhaust channel 431 is formed by a slit in the surface of the cooling chuck 43 that is covered by the donor plate.

[0071] The cooling chuck 43 can be forced to cool by cooling channels (not shown) through which a cooling liquid circulates. Each contact pin 41, 42, 41′, e.g., a pogo pin, extends through an opening in the cooling chuck 43 and provides electrical connection to a respective electrical contact 37, 38, 37′ of the resistive heater layer 33. When the exhaust channels are evacuated, the donor plate 3 is clamped against the support unit 4 by a relatively high environmental pressure compared to the pressure in the exhaust channels. This improves the electrical connection between each contact pin 41, 42, 41′ and each electrical contact 37, 38, 37′.

[0072] FIG. 5H illustrates the application of a pulse of power to the resistive heater layer in zone 32. The duration of the pulse is long enough to heat surface 31s in subzone 32d above threshold temperature Tth, but short enough to prevent surface 31s from reaching the threshold temperature in subzones 32c, 32b, and 32a, where thermal buffer layer portions 34c, 32b, and 32a are located. This vaporizes a portion 7ae of the propellant in layer 7 below component Ca. Due to the relatively thick layer 7, the remaining portion 7ar of the propellant is expelled along with component Ca toward surface TS of target T. The relatively thick layer 7 acts as an insulator, ensuring that the component remains relatively cool. In the illustrated example, component Ca is transferred to lands with electrical contacts c1 and c2 on respective bond pads b1 and b2, which are connected to respective conductors e1 and e2.

[0073] FIG. 5I illustrates the subsequent situation, in which components Ca and Cb have already been transferred to target T. Again, a pulse of power is applied to the resistive heater layer in zone 32. Here, the duration of the pulse is long enough to heat surface 31s in subzone 32c above threshold temperature Tth, but short enough to prevent surface 31s from reaching the threshold temperature in subzone 32d, where thermal buffer layer portion 34d is thicker than thermal buffer layer portion 34c. This causes a portion 7ce of the propellant in layer 7 below component Cc to evaporate. Due to the relatively thick layer 7, the remaining propellant 7cr is expelled along with component Cc toward surface TS of target T. The relatively thick layer 7 serves as an insulator, ensuring that the transferred component Cc and component Cd, which remains on donor plate 3 at this stage, remain relatively cool. In the illustrated example, component Cc is transferred to the lands with its electrical contacts c1 and c2 on respective bond pads b1' and b2', connected to respective conductors e1' and e2'.

[0074] 6A-6C show another embodiment, in which adhesives for bonding components in different subzones of the donor surface 31s have different threshold temperatures. In the illustrated example, adhesive 7b bonding component Cb in the second subzone 32b has a threshold temperature Tthb higher than the threshold temperature Ttha of adhesive 7a bonding component Ca in the first subzone 32a of the donor surface 31s. Furthermore, in this example, adhesive 7c in the third subzone 32c has a threshold temperature Tthc higher than the threshold temperature Tthb of adhesive 7b in the second subzone 32b. Similarly, adhesive 7d in the fourth subzone 32d has a threshold temperature Tthd higher than the threshold temperature Tthc of adhesive 7c in the third subzone 32c. As mentioned above, the threshold temperature of the adhesive can be easily modified by adding a photoacid generator. Prior to placing the components on the donor plate, the adhesive coating is exposed to different doses of photoacid generator to control the decomposition temperature per subzone within the zone. Other additives can be used, but may be more difficult to pattern. An example of tuning polymer decomposition is described in Phillips et al., "Polymer Degradation and Stability," in Science Direct, Volume 125, March 2016, Pages 129-139.

[0075] As shown in Figure 6B, components Ca, Cb, Cc, Cd, ... can be adhered to adhesive layers 7a, 7b, 7c, 7d using a temporary carrier TC in the same manner as shown in Figure 5C for embodiments using a patterned thermal buffer layer. The components can then be released from the temporary carrier TC, for example, by using UV radiation, as shown in Figure 5D.

[0076] In one example of this embodiment, the thermal buffer layer is absent or of uniform thickness.

[0077] 6C illustrates the controller in its first operating state, causing power supply 6 to supply a first power pulse to at least one heater element 33 to heat donor plate surface 31s in at least first subzone 32a to a surface temperature above the threshold temperature Ttha of adhesive 7a in first subzone 32a. This causes at least a portion 7ae of adhesive layer 7a to evaporate, and vapor pressure drives component Ca toward the target and deposits it thereon. Heater element 33 heats the entire donor plate surface 31s in zone 32. However, because adhesive specimens 7b, 7c, and 7d have higher threshold temperatures, components Cb, Cc, and Cd remain adhered to the donor plate.

[0078] After the controller causes the target manipulation device 2 (21, 22) to laterally reposition relative to the donor plate, the second operating state transitions to a third operating state, causing the power supply 6 to supply a second power pulse to at least one heater element 33 to heat the donor plate surface 31s in the second subzone 32b to a surface temperature above the threshold temperature Tthb of the adhesive 7b in the second subzone 32b. This transfers the second component Cb. Similarly, the third component Cc and the fourth component Cd can be transferred by subsequently supplying third and fourth pulses of power to the heater element 33. If necessary, the controller causes the target manipulation device 2 (21, 22) to laterally reposition the target T relative to the donor plate between the second pulse and / or between the third and fourth pulses.

[0079] Additionally, forced cooling of zone 32 between successive power pulses can be achieved by cooling the donor plate 3 with a cooling chuck 43 in thermal contact with the donor plate 3. In one example, the cooling chuck 43 is in permanent contact with the donor plate 3 during operation, and when a pulse of power is applied to the heater elements, the heat flux provided by the heater elements to the donor plate surface 31s exceeds the heat flux directed toward the cooling chuck. This embodiment has the advantage of having minimal moving parts and being relatively easy to control. Furthermore, because cooling occurs immediately after the end of the pulse, operation can occur at high speeds. In another embodiment, a controller controls an actuator that brings the cooling chuck into thermal contact with the donor plate at the end of the pulse and breaks thermal contact at the beginning of the pulse. This embodiment is attractive when high operating speeds are not required, as heating occurs with a smaller amount of energy.

[0080] In another example, samples with different threshold temperatures are used in combination with an embodiment in which the donor plate includes thermal buffer layers of different thicknesses in each subzone.

[0081] 7A-7D show yet another embodiment in which the donor plate 3 is provided with spacer pillars 39a-39d to support components at different distances from the heater element 33. In the illustrated embodiment, the heater element 33 is a resistive heater layer. In another embodiment, the heater element is an optical radiation absorbing layer that is heated by directing optical radiation thereon.

[0082] As shown in FIG. 7A, subzone 32a has spacer pillar 39a to support components relatively close to the heater element. Subzones 32b, 32c, and 32d then have longer spacer pillars 39b, 39c, and 39d to support components further away from heater element 33. The pillar height controls the heat sink effect on the components above it. The lower the pillar height, the stronger the heat sink effect. This ensures that, when heating a zone, the temperature of the surface within the subzone between the lower pillars remains lower than the temperature of the subzone between the upper pillars. This allows for exceeding a single predetermined threshold temperature in successive subzones with successively taller pillars by generating heating pulses of successively increasing duration and / or power.

[0083] Figure 7B shows that the adhesive layer 7 has been uniformly deposited on the surface of the donor plate 3 provided with the spacer pillars 39a-39d, which can most easily be done by spin coating.

[0084] If the adhesive layer is provided as a positive photoresist, layer 7 is selectively irradiated outside the areas between the pillars where adhesive specimens 7a, 7b, 7c, and 7d will be formed to bond the components. After irradiation, the excess irradiated photoresist can be removed, leaving only the partially cured portions 7a, 7b, 7c, and 7d between the pillars, as shown in Figure 7(c).

[0085] Optionally, the adhesive used is a photoresist containing a photoacid generator, and the threshold temperatures of the adhesive portions 7a, 7b, 7c, 7d in different subzones can be modified to different values ​​by activating the photoacid generator to different degrees, as determined by the duration or intensity of irradiation with light radiation (e.g., UV radiation).

[0086] Since the adhesive portions 7a, 7b, 7c, and 7d are partially cured by light radiation of different intensities and / or durations, they have different threshold temperatures, which increase in the order 7a, 7b, 7c, and 7d.

[0087] The spacer pillars 39a-39d control the adhesive thickness between the chip and the heater. Controlling the heat dissipation effect on the components helps create thermal contrast. In particular, since the adhesive is polymer-based and has low thermal conductivity (~0.2 W / mK), slight thickness differences have a significant effect on the temperature rise at the heater / adhesive interface. As an example, the spacer pillars 39a-39d can have a height selected from the range of 50 nm to 50 μm.

[0088] As shown in Figure 7(d), when components Ca, Cb,... are pressed against spacer pillars 39a-39d, the components are bonded to adhesive portions 7a, 7b, 7c, and 7d, with the adhesive laterally distributed across the donor plate surface between spacer pillars 39a-39d. Adhesive portions 7a, 7b, 7c, and 7d are prevented from contacting the pillars by partially curing a volume of adhesive smaller than the volume enclosed by the pillars. This prevents shear forces from being generated by the adhesive bonded to the pillars when the part is transferred.

[0089] 8A and 8B show a plate of an embodiment of a deposition apparatus including multiple subzones 32a, 32a',...; 32b, 32b',...; 32c, 32c'; 32d, 32d') in which zone 32 has a condition where the surface temperature exceeds the threshold temperature of the adhesive layer when the same power pulse is applied.

[0090] 8A is a top view of a single zone 32 of donor plate 3 divided into 5 x 5 sections. Each of the 25 sections has its thermal buffer layer patterned in the same way. For example, as shown in FIG. 8B, which shows a cross section through five sections B1-B5 of plate 3 along B-B in FIG. 8A, the sections have first subzones 32a, 32a',..., second subzones 32b, 32b',..., in which the buffer layer 34 has a thickness of 0, and the buffer layer 34 has a first thickness different from 0, and third subzones 32c, 32c',..., in which the buffer layer 34 has a second thickness different from 0 and different from the first thickness.

[0091] As shown in Figure 8(c), supplying a first power pulse to heater element 33 of zone 32 transfers all components Ca, Ca', Ca', Ca'' in the first subzone of the subsection to target surface TS of target T, while the remaining components remain attached to plate 3. A subsequent power pulse having a longer duration or magnitude transfers the next set of components from second subzone 32b, 32b' (see Figure 8B), where buffer layer 34 has a first thickness, etc.

[0092] As shown in FIG. 9, the component transferred to the target surface TS of the target T may be a material for providing interconnections on the target surface or a material for providing thermal and / or electrical insulation. In the example shown in FIG. 9, the material is solder for forming bond pads b on the surface. In the illustrated example, the plate 3 includes multiple zones 32, 32′, each with a respective heater element 33, 33′. Each zone is divided into subzones 32a, 32b, 32c, and 32d. These subzones are distinguished from each other by the thickness of the thermal buffer layer therein. In subzone 32a, the thickness of the thermal buffer layer is zero. Adhesion specimens 7a, 7b, 7c, and 7d within these subzones are formed from the material of the component to be deposited. In this example, the material is solder paste. The solder paste has the following composition, by way of example:

[0093] Solid content 85±5wt% Material Solids Purpose Metal alloy (SAC305): 85±5 wt% conductivity Flux 10±5% wt% Oxide removal Other 5±5wt% Printability

[0094] This example solder paste has a viscosity in the range of 100-1000 Pa*s. In contrast to conventional screen printing pastes and inks, shear thinning can be minimized, for example, by adding fumed silica to prevent past flow on the acceptor substrate. This can also be prevented by curing / drying the ink, for example, by laser irradiation, which can be conveniently achieved by a high solids content and low solvent content.

[0095] In the example of FIG. 9, a first pulse is provided to heat zone 32. In subzone 32a, the thermal buffer layer has zero thickness. This causes the temperature of surface 31s within subzone 32a to exceed the threshold temperature of the solder within subzone 32a, i.e., the temperature at which the portion of the solder paste (7ae) in contact with surface 31a vaporizes, causing the remaining portion of the solder paste within subzone 32a (7ar) to transfer to the target surface forming bond pad b. Following relative lateral displacement of plate 3 and the target, a next power pulse of longer duration or magnitude is provided to heat zone 32. This causes the temperature of surface 31s within subzone 32b to exceed the threshold temperature of the solder paste therein, causing a major portion of it in molten form to transfer to the target surface forming bond pad b, and so on.

[0096] As mentioned above, the same principles can be applied to other materials deposited to form electrical or thermal contacts or to provide thermal or electrical insulation. Deposition may also be performed collectively on groups of electrically or thermally conductive or insulating components, as described with reference to Figures 8A-8C. It is also possible to tailor the threshold temperature of a component material, for example, by selectively activating a photoacid generator contained in the component.

[0097] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single component or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be interpreted as limiting the scope.

Claims

1. A deposition device (1) for depositing components (Ca, Cb, ...) on a target surface (TS) of a target (T), comprising: a donor plate (3) and at least one heater element (33) for heating the donor plate surface (31s) in at least one zone (32), a donor plate (3) and at least one heater element (33), the donor plate surface (31s) being configured to temporarily bond respective components with respective adhesives (7a, 7b, ...) in respective sub-zones (32a, 32b, ...) of the at least one zone (32), and the adhesive bonding the components in each sub-zone evaporates when the temperature of the donor surface in each sub-zone exceeds a threshold temperature of the adhesive; a power supply (6) configured to controllably supply pulses of power to at least one of the heater plate surfaces (31s) to heat the donor plate surface (31s) within the at least one zone (32); a target handling device (2; 21, 22) for positioning the target (T) laterally relative to the donor plate (3); a controller (5) configured to control the power supply (6) and the target manipulation device (2; 21, 22) while holding the target surface (TS) facing the donor plate surface (31s), wherein in a first operating state, the controller (5) causes the power supply (6) to supply at least a first pulse (Pulse 1) of power to the at least one heater element (33) to heat the donor plate surface (31s) in at least a first sub-zone (32a) to a threshold temperature of the adhesive (7a) in the first sub-zone (32a); a controller (5) for, in a second operating state, causing the target manipulation device (2) to vary a lateral position of the target (T) relative to the donor plate (3), and for, in a third operating state, causing the power source (6) to supply at least a second pulse (Pulse 2) of power to at least one of the heater elements to heat the donor plate surface (31s) at least in a second sub-zone (32b) to a surface temperature exceeding a threshold temperature of the adhesive (7b) in the second sub-zone (32b); A deposition device (1) comprising:

2. 2. The deposition apparatus (1) of claim 1, wherein the donor plate comprises a thermal buffer layer (34b) between the at least one heater element (33) and the donor plate surface (31s) in the at least one second subzone (32b).

3. 3. The deposition device (1) according to claim 2, wherein the thermal buffer layer is made of a ceramic material and has a thickness of less than or equal to 2 μm.

4. 4. The deposition device (1) according to claim 1, wherein the adhesive (7b) bonding the component (Cb) in the second subzone (32b) of the donor surface (31s) has a higher threshold temperature (Tthb) than the adhesive (7a) bonding the component (Ca) in the first subzone (32a) of the donor surface (31s).

5. The deposition apparatus (1) according to any one of claims 1 to 4, comprising a support unit (4) for supporting said donor plate (3) during operation.

6. 6. The deposition apparatus (1) of claim 5, comprising a cooling chuck (43) in thermal contact with the donor plate (3) for cooling the donor plate (3) between subsequent pulses.

7. 7. The deposition apparatus (1) of claim 6, wherein the cooling chuck (43) comprises cooling channels for passing a cooling liquid.

8. 8. The deposition apparatus according to claim 5, wherein the support unit (4) comprises a vacuum channel that is evacuated to clamp the donor plate (3) against the support unit (4) by an environmental pressure that is relatively high compared to the pressure in the exhaust channel.

9. The deposition apparatus (1) according to any one of claims 5 to 8, wherein the support unit (4) comprises respective contact pins (41, 42, 41') for providing electrical connection with respective electrical contacts (37, 38, 37') of the resistive heater layer (33).

10. 10. The deposition apparatus (1) according to any one of claims 1 to 9, wherein the donor plate surface (31s) of the donor plate (3) comprises spacer pillars (39a-39d) for supporting the components at different distances from the heater element (33).

11. 11. The deposition device (1) according to any one of claims 1 to 10, wherein the zone (32) comprises a plurality of sub-zones (32a, 32a', ...; 32b, 32b', ...; 32c, 32c'; 32d, 32d') having a condition that, when supplied with the same power pulse, the surface temperature therein exceeds a threshold temperature of the adhesive layer.

12. A method for depositing components (Ca, Cb, ...) on a target surface (TS) of a target (T), comprising the steps of: providing a donor plate (3) having at least one heater element (33) for heating a donor plate surface (31s) of the donor plate (3) in at least one zone (32) of the donor plate (3); - adhering each of the components (Ca, Cb, ..) together with a respective adhesive layer (7a, 7b, ..) to a donor surface (31s) in each of the sub-zones (32a, 32b) of said at least one zone (32), wherein the adhesive layer adhering the components of each sub-zone evaporates when the temperature of the donor plate surface of each sub-zone exceeds a threshold temperature of the donor plate surface of each sub-zone; Positioning a target surface (TS) facing the donor plate surface (31s) of the donor plate (3); supplying at least a first pulse of power to said at least one heater element (33) to heat the donor surface (31s), wherein the temperature of the donor surface in at least a first one of the subzones (32a) assumes a value that is a threshold temperature of an adhesive type (4a) that adheres a first component (Ca) in said first one of the subzones for dispensing said first component (Ca), and the temperature of the donor surface in at least a second one of the subzones (32b) assumes a value that does not exceed a threshold temperature of an adhesive layer (7b) that adheres a component (Cb) in said second one of the subzones; translating the target (T) laterally relative to the donor plate (3); supplying at least a second pulse of power to the at least one heater element (33) to heat the donor surface (31s) so that the temperature of the donor surface in the second one of the subzones (32b) is at least a value that is a threshold temperature of the adhesive (7b) that adheres the component (Cb) in the second one of the subzones (32b) and ejects the component (Cb) in the second subzone (32b) towards the target (T); A method comprising:

13. 13. The method of claim 12, further comprising providing the donor plate (3) with a thermal buffer layer (34b) between the at least one heater element (33) and the donor plate surface (31s) in the at least one second subzone (32b).

14. 14. The method according to claim 12 or claim 13, comprising bonding the component (Cb) in the second subzone (32b) of the donor surface (31s) with an adhesive (7b) having a higher threshold temperature (Tthb) than an adhesive (4a) bonding the component (Ca) in the first subzone (32a) of the donor surface (31s).

15. 15. The method of claim 14, comprising depositing a precursor of the sample that includes a photoacid generator (PAG) and partially curing the precursor in different subzones having different cure conditions to provide an adhesive layer with different threshold temperatures.

16. The method according to any one of claims 12 to 14, wherein in the bonding step (S2), the adhesive layer has a thickness in the range of 0.1 μm to 10 μm.

17. The step of bonding each of the components (Ca, Cb, ...) pressing the temporary carrier (TC) with the components adhered to it against a donor plate surface (31s) provided with an adhesive material; removing the temporary carrier (TC) to leave the components (Ca, Cb, ...) adhered to the adhesive on the surface (31s) of the donor plate (3); The method according to any one of claims 12 to 16, comprising:

18. 18. The method of claim 17, wherein the temporary carrier (TC) is a photosensitive release tape or a thermal release tape, and the adhesion of the components (Ca, Cb, ...) to the photosensitive release tape is reduced by irradiating the photosensitive release tape with light radiation or by heating the thermal release tape.

19. the adhesive material provided on the surface (31s) of the donor plate (3) is a positive photoresist; 19. The method according to any one of claims 12 to 18, wherein after adhering each of the components (Ca, Cb, ...), a side (31) of the donor plate (3) having the components (Ca, Cb, ...) adhered to its surface (31s) is exposed to UV radiation the portions of the positive resist present between the components, and then the exposed portions of the positive resist are removed.

20. providing spacer pillars (39a, 39b, 39c, 39d) of different heights on the donor plate surface (31s) of different subzones (32a, 32b, 32c, 32d); providing adhesive (7a, 7b, 7c, 7d) between the pillars in the subzones at a height exceeding the height of said pillars; Pressing each component against the pillars in the respective zones, thereby contacting the component with adhesive and adhering the component to the donor plate surface (31s). The method according to any one of claims 12 to 19, comprising:

21. 21. The method of claim 20, wherein the spacer pillars are made of a conductive material, and wherein pressing each component against the pillars includes electrically connecting each electrical contact of the component with a respective pillar for testing the component.

22. Providing an adhesive sample uniformly depositing a precursor photoresist on the donor plate surface (31s) having the spacer pillars (39a, 39b, 39c, 39d) to a height exceeding the height of the highest spacer pillar; selectively exposing the layer of photoresist to actinic radiation, leaving unexposed respective volumes of the photoresist between the pillars in each subzone, each said volume being smaller than the volume defined between the pillars in each subzone, while hardening the photoresist of the layer not within said volumes; removing the irradiated photoresist; 22. The method of claim 20 or claim 21, comprising:

23. the photoresist comprises a photoacid generator; 23. The method of claim 22, wherein after the step of removing the respective volumes of the hardened photoresist in the zones, the respective volumes of the photoresist in the zones are partially activated to different degrees by irradiating them with light radiation at different intensities or durations to achieve different threshold temperatures.

24. A donor plate (3) for use in a deposition apparatus (1), comprising: the donor plate surface (31s) is configured to be temporarily adhered to a respective component by a respective adhesive layer (7a, 7b, ..) in each sub-zone (32a, 32b, ..) of said at least one zone (32) so as to heat the donor plate surface (31s) with at least one heater element (33) in at least one zone (32); When the temperature of the donor surface of each subzone exceeds a threshold temperature of the donor surface of each subzone, the adhesive layer adhering the components within the respective subzone evaporates; the donor plate includes, in at least one second subzone (32b), a thermal buffer layer (34b) between at least one heater element (33) and the donor plate surface (31s); Donor plate (3).

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