Apparatus and method for securing a die for die bonding

Abstract

An apparatus and method for securing an at least partially transparent carrier to a chuck are provided, wherein the chuck and / or chucking mechanism is at least locally substantially transparent to radiation used to release one or more donor die from the carrier.

Description

APPARATUS AND METHOD FOR SECURING A DIE FOR DIE BONDINGCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of EP application 24157838.4 which was filed on February 15, 2024 which is incorporated herein in its entirety by reference.TECHNICAL FIELD

[0001] The present disclosure relates generally to an apparatus and method for holding a die for die bonding.BACKGROUND

[0002] In manufacturing processes of integrated circuits (ICs), multiple finished or unfinished ICs (e.g., whole wafers, diced wafers, partially diced wafers, chips, die, etc.) may be placed in contact, stacked, bonded, or otherwise joined (e.g., to heterogeneous or homogeneous devices) at various points in the fabrication process. Heterogeneous integration, e.g., the integration of different circuits or other patterned devices, may rely upon joining of specific portions (for example, conductive contact elements) of multiple die — where these specific portions may be aligned in three-dimensional space to ensure functional connectivity. Alignment of these die, which may have multiple fabrication layers, different critical dimensions, different nodes, packaging, etc., with each other may require different techniques than used for lithography during fabrication. As the physical sizes of IC components continue to shrink, and their structures continue to become more complex, accuracy and throughput in integration become more important. For applications such as heterogeneous integration, it may be desirable to obtain both accurate and fast placement of die with respect to one another. In the context of semiconductor manufacture, improvements in die placement and alignment (e.g., improvements in heterogeneous integration) lead to improvements in IC manufacturing and integration abilities.

[0003] For die bonding with radiation-mediated release, it may be important to hold the die such that they may be exposed in a controlled manner to radiation, which may not be possible with traditional chucking mechanisms.SUMMARY

[0004] According to an embodiment, there is provided a chuck configured to hold a carrier with one or more donor dies, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier.

[0005] According to an embodiment, there is provided a system for positioning donor dies at acceptor locations comprising a chuck as described herein.

[0006] According to an embodiment, there is provided a high-volume manufacturing tool comprisinga chuck as described herein.According to an embodiment, there is provided a system comprising: a chuck as described herein; and a positioning system configured to position the chuck and one or more donor dies held thereon relative to one or more acceptor locations.According to an embodiment, there is provided a method comprising: positioning a carrier supporting one or more donor dies near a face of a chuck, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier; activating a holding mechanism configured to hold the carrier to the face of the chuck; and controlling a relative position of the chuck and an acceptor location such that at least one donor die of the one or more donor dies aligns with the acceptor location for die bonding.

[0007] According to another embodiment, one or more non-transitory, machine -readable medium is provided having instructions thereon, the instructions when executed by a processor being configured to perform a method as described herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0009] Figures 1A-1D are schematic diagrams illustrating an exemplary die bonding method, according to one or more embodiments.

[0010] Figures 2A-2F are schematic diagrams illustrating an example method of die placement, according to one or more embodiments.

[0011] Figures 3A-3I are schematic diagrams illustrating portions of an example apparatus for die bonding, according to one or more embodiments.

[0012] Figure 4 is a schematic diagram illustrating an example edge holding method of securing a die, according to one or more embodiments.

[0013] Figures 5A-5C are schematic diagrams illustrating an example electrostatic holding method of securing a die, according to one or more embodiments.

[0014] Figures 6A-6G are schematic diagrams illustrating an example fluid-based surface tension method of securing a die, according to one or more embodiments.

[0015] Figure 7 is a flowchart which illustrates an exemplary method of die placement, according to one or more embodiments.

[0016] Figure 8 is a flowchart which illustrates an exemplary method of die bonding, according to one or more embodiments.

[0017] Figure 9 is a block diagram of an example computer system, according to one or moreembodiments of the present disclosure.DETAILED DESCRIPTION

[0018] Embodiments of the present disclosure are described in detail with reference to the drawings, which are provided as illustrative examples of the disclosure so as to enable those skilled in the art to practice the disclosure. Notably, the figures and examples below are not meant to limit the scope of the present disclosure to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements. Moreover, where certain elements of the present disclosure can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present disclosure will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the disclosure. Embodiments described as being implemented in software should not be limited thereto, but can include embodiments implemented in hardware, or combinations of software and hardware, and vice-versa, as will be apparent to those skilled in the art, unless otherwise specified herein. In the present specification, an embodiment showing a singular component should not be considered limiting; rather, the disclosure is intended to encompass other embodiments including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein. Moreover, applicants do not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such. Further, the present disclosure encompasses present and future known equivalents to the known components referred to herein by way of illustration.

[0019] Although specific reference may be made in this text to the manufacture of ICs, it should be explicitly understood that the description herein has many other possible applications. For example, it may be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal display panels, thin-film magnetic heads, etc. The skilled artisan will appreciate that, in the context of such alternative applications, any use of the terms “wafer” or “die” in this text should be considered as interchangeable with the more general terms “substrate” and “target portion”, respectively. The term “wafer” may be used generally to refer to a large unit of manufacture (which may be the largest unit of manufacture), while the term “die” may be used to refer to a smaller unit of manufacture which may correspond to a lithography pattern, a portion of a lithography pattern, multiple lithography patterns, etc. A “die” may correspond to a portion of “wafer” — that is a “die” may be produced by dicing or otherwise dividing a “wafer”. The term “die” should be considered as interchangeable with the term chip, chiplet, or other terms for IC divisions. A patterning device (for example, a lithography device) can comprise, or can form, one or more patterns, which may correspond to one or more die. The patterns can be generated utilizing CAD (computer-aided design) programs, based on a pattern or design layout, this process often being referred to as EDA (electronic design automation). As used throughout this application “or”, unlessindicated otherwise, takes a non-exclusive meaning, e.g., encompassing both “and” and “or”. “Each”, “every”, “all”, “corresponding”, “individual” and other relational terms encompass substantially “each”, “every”, “all”, etc., including cases in which each, every, all, corresponding, individual, etc. may include relationship which are not one-to-one, or do not include every possible item. For example, every may exclude items, such as items determined to be defective during testing. Each may exclude items, such as edge items, which are not used. All may exclude items, such as excess items. Corresponding may not require that items correspond in an exactly one to one manner. For example, a first item may correspond to two of a second item or vice versa. In some cases, individual may refer to multiple of an item, such as each item A has individual item B, where an item A may have two of an item B.

[0020] Reference is now made to Figures 1A-1D, which are schematic diagrams illustrating an exemplary die bonding method consistent with embodiments of the present disclosure. The exemplary die bonding method is depicted in relation to a reference set of axes, which are consistent through the schematic illustrations. The reference axes are provided for ease of description only and are not to be taken as limiting. Included methods and apparatuses may instead be described with reference to a different set of axes (e.g., cylindrical coordinates, polar coordinates, etc.), a different origin point (e.g., an origin point in the donor die, an origin point in the target, origin point in between the donor die and target, etc.), or a different orientation. The reference set of axes is chosen such that the fabrication plane of the die (i.e., a substrate surface) lies in the x-y plane and where the fabrication direction is parallel or antiparallel to the z-axis for both the donor die and target locations.

[0021] As shown in Figures 1A-1D, the exemplary die bonding method may involve a donor die 102 and a target die 104. Herein, the term “donor” and the term “target” are used for ease of description. It should be understood that the term “donor” and the term “target” are provided for reference and are relative descriptions, and that elements described as corresponding to a “donor” can instead correspond to a “target” and vice versa. A target die may also or instead be called an acceptor die. Further, while just one donor die and target die are depicted in Figure 1 A, it will be appreciated that there may be multiple such die and that multiple donor die may be essentially simultaneously bonded with multiple target die, e.g., where, for example, multiple die are still part of (all or part) a substrate in or on which they are formed.

[0022] The donor die 102 may have one or more electrically active areas 106, such as on an alignment face of the donor die 102. The one or more electrically active areas 106 may be conductive, such as metal. The one or more electrically active areas 106 may correspond to one or more vias (e.g., one or more through silicon vias (TSVs)), one or more electrical contact lines, one or more contact pads, one or more packaging pads, or other one or more electrically conductive areas. The donor die 102 may have one or more electrically inert areas (for example, an electrically insulating area) outside of the one or more electrically active areas 106, such as on the alignment face of the donor die 102. The one or more electrically active areas 106 may be recessed (as shown) with respect to one or moreother surfaces of the donor die 102. The one or more electrically active areas 106 may correspond to one or more contacts (e.g., to source, to drain, to gate, etc.) to one or more electrical devices within the donor die 102 (not shown). The target die 104, likewise, may have one or more electrically active areas 108, which may have one or more similar properties to the one or more electrically active areas 106.

[0023] The donor die 102 may also or instead have one or more doped areas 110, such as on an alignment face of the donor die 102, recessed below the alignment face of the donor die 102, etc. While the term “doped” is used, it should be understood that the one or more doped areas 110 may be any areas which, through the course of fabrication, come to have one or more different electrical characteristics than the bulk of the substrate (e.g., silicon wafer). The one or more doped areas 110 may correspond to source, drain, gate, ground, or other areas of a circuit which is doped or otherwise altered (e.g., through implantation, oxide growth, thin film deposition, etc.) to have a different electrical characteristic than the bulk of the substrate. The one or more doped areas 110 may include one or more conductive layers (e.g., one or more highly doped or electrically conductive layers) and / or one or more insulative layers (e.g., one or more oxide layers). The donor die 102 may have one or more undoped areas (for example, an area where the substrate retains the characteristic of the bulk substrate) outside of the one or more doped areas 110, such as on the alignment face of the donor die 102. The one or more doped areas 110 may be recessed, buried, coplanar (as shown), etc. with respect to one or more other surfaces of the donor die 102. The one or more doped areas 110 may correspond to one or more regions (e.g., to one or more source regions, one or more drain regions, one or more gate regions, one or more dielectric regions, etc.) of one or more electrical devices within the donor die 102 or one or more regions which may form one or more electrical devices across both the donor die 102 and the acceptor die 104 once those die are bonded. The target die 104, likewise, may have one or more doped areas 112, which may have one or more similar properties to the one or more doped areas 110.

[0024] As shown in Figures 1A and IB, the exemplary die bonding method may involve alignment of at least one of the electrically active areas 106 and / or doped areas 110 of the donor die 102 with at least one of the electrically active areas 108 and / or doped areas 112 of the target die 104. The exemplary die bonding method may involve bringing the donor die 102 into contact with the target die 104 while maintaining alignment between, e.g., one or more electrically active areas 106 and one or more electrically active areas 108 so that the one or more electrically active areas 106 and the one or more electrically active areas 108 may be joined for cross-die electrical communication. The exemplary die bonding method may involve aligning one or more doped areas 110 of the donor die 102 with one or more doped areas 112 of the target die 104. Aligning may encompass bringing into contact, aligning one or more edges of various regions, having overlap, having non-overlap, or any other appropriate alignment scheme. The exemplary die bonding method may involve applying or maintaining pressure between the donor die 102 and the target die 104, while bonding occurs betweenthe donor die 102 and the target die 104. The donor die 102 may be supported by a carrier structure 114, which may be a substrate which is at least partially transparent to a range of radiation (e.g., infrared radiation, a portion of the optical spectrum, etc.). The carrier structure 114 may be supported (e.g., held) by a chuck (not depicted), which may provide movement (e.g., for aligning in the x-y plane, for placement in the z direction, etc.) to the carrier structure 114 and dies thereon. The target die 104 may likewise be supported by a carrier structure 116, which may or may not be transparent to a range of radiation. The carrier structure 116 may be supported by a chuck (not depicted), which may or may not provide movement (e.g., for aligning in the x-y plane, for placement in the z direction, etc.) to the carrier structure 114 during the die bonding. The alignment may be complicated by the multiple layers of the donor die 102 or the multiple layers of the target die 104, which may be optically opaque.

[0025] Figures 1A and IB depict a cross-sectional view of portions of the exemplary die bonding method showing relative positioning between the donor die 102 and the target die 104. As shown in Figure 1A, the donor die 102 and the target die 104 may be brought together along the z-axis, while the position of the donor die 102 or the target die 104 may be adjusted in the x-y plane (e.g., perpendicular to the z-axis of approach), such as to improve alignment between the donor die 102 and the target die 104. As shown in Figure IB, alignment can be achieved between, e.g., one or more electrically active areas 106 and one or more electrically active areas 108 and / or between one or more doped areas 110 of the donor die 102 with one or more doped areas 112 of the target die 104.

[0026] Once aligned, the donor die 102 and the target die 104 are bonded together. In an embodiment, the bonding is a direct or fusion bonding (e.g., involving van der Waals forces). In an embodiment, the bonding is an intermolecular bonding, e.g., van der Waals bonding. In an embodiment, the bonding may include covalent, ionic, or metallic (e.g., chemical) bonding, e.g., hydrogen bonding. In an embodiment, the bonding is aided by a material (e.g., a suitable bonding or adhesive material) applied to an alignment surface of the donor die 102 and / or target die 104 or provided to a gap between the donor die 102 and the target die 104 (e.g., in the form of gas or liquid). In some embodiments, physical contact between the donor die 102 and the target die 104 may include bonding, such as through a bonding wavefront generated by contact (or atomic level proximity), such as of a surface prepared for hydrogen bonding.

[0027] As shown in Figure IB, the donor die 102 and the target die 104 may be annealed after contact as depicted by the wavy lines (while wavy lines are shown here at both the donor die 102 and the target die 104, the annealing agent need not be provided at both the donor die 102 and the target die 102 nor needs to be applied in the direction(s) shown). Annealing may be or include heat annealing, electrical annealing, electrostatic processes, etc. In some embodiments, annealing may include annealing of in-plane (or prominent) regions that are bonded and / or annealing of one or more recessed areas which may increase the volume of fill in a recess area (such as through thermal expansion, capillary force, etc.) and may cause physical contact and bonding of areas previously notin contact. As shown in Figure 1C, annealing may cause physical or chemical changes, such as in the one or more electrically active areas 106 of the donor die 102 or in the one or more electrically active areas 108 of the target die 104, which may cause or improve physical contact or electrical contact between an electrically active area 106 and an electrically active area 108. Annealing may therefore produce or enhance electrical connectivity between elements of the donor die 102 and the target die 104 (e.g., integration). This electrical connectivity may occur even if an electrically active area 106 and an electrically active area 108 differ — for example, have different recessed depths, are made up of different materials, have different dimensions, etc. In an embodiment, the prior bonding described with respect to Figure 1 A may be temporary during one or more portions of the annealing process, wherein the annealing process forms tight connections between donor die 102 and the target die 104. In an embodiment, the annealing may occur in the system where the bonding occurs. In an embodiment, the annealing may occur in a separate system from the system in which the bonding occurs, e.g., the donor and target dies are transported out of the bonding system into an annealing system which can include one or more heating elements (e.g., one or more electrical heating elements, one or more elements to provide radiation heating, etc.) to provide the heat for the annealing.

[0028] Once the donor die 102 and the target die 104 are bonded, the carrier structure 114 may be removed as shown in Figure IB. Additionally or alternatively, the carrier structure 116 may be removed then as well. Alternatively, once the donor die 102 and the target die 104 are annealed, the carrier structure 116 may be removed as shown in Figure 1C. Additionally or alternatively, the carrier structure 114 may be removed then as well.

[0029] Figure ID depicts a plan view of an example die bonding method according to this disclosure. As shown in Figure ID, the donor die 102 and the target die 104 may have one or more alignment marks along the x-y plane to facilitate alignment of the die as a whole. Alignment marks in the x-y plane of a die (e.g., one or more alignment marks 120 on the donor die 102 or one or more alignment marks 122 on the target die 104) may reduce the area available for circuitry. One or more alignment marks may be placed in a waste area, such as an area between chips, which may then be destroyed (e.g., removed) during dicing. Dicing herein refers to mechanical separation of areas of a substrate (e.g., a unit of manufacture) into smaller areas (e.g., dies or chips) which may contain one or more units of operation (e.g., a logic device, a memory unit, etc.). Dicing may operate using any appropriate method — for example, scribing and breaking, mechanical sawing, laser cutting, etc. — and may destroy (e.g., grind to powder or otherwise render inoperable for circuitry placement) a non-zero linewidth portion of the substrate volume when separating die. Alignment marks may be additively or substractively fabricated, such as by etching or deposition in the z-direction. Alignment marks 120 and 122 may be the same or different. Alignment marks 120 and 122 may be a multi -directional alignment mark, i.e., capable of determining alignment in more than one direction, such as a bidirection alignment mark, an example of which is shown as mark 120 in Figure ID. The alignment mark 120 and / or alignment mark 122 may be a fine alignment mark, such as for alignment in the pmscale. The alignment mark 120 may be located on the donor die 102 while the target die 104 may have an alignment mark 122 located in a waste area, or vice versa. Alternatively or additionally, one or more electrically active and / or doped areas of the donor die 102 or one or more electrically active and / or doped areas of the target die 104 (not shown in Figure ID) or other surface features may function as a reference for alignment (e.g., an alignment mark) of the donor die 102 and / or the target die 104.

[0030] The donor die 102 and the target die 104 may be aligned in up to three dimensions before or during contact between the donor die 102 and the target die 104. For example, the donor die 102 or the target die 104 may be positioned in the x-y plane as the donor die 102 in the target die 104 are contacted. The donor die 102 or the target die 104 may be positioned by operation of a die actuator or other die-scale elements, such as by piezoelectric stepper elements, or by operation of a chuck or other carrier structure-scale elements, such as by a motor or other actuator. The position of the donor die 102 or the target die 104 may be adjusted with respect to up to six degrees of freedom. For example, given an origin point at a central part of the donor die 102, the donor die 102 may be positioned by movement along the X axis (e.g., in a positive or negative X direction), along the y-axis (e.g. in a positive or negative Y direction), along the z-axis (e.g., in a positive or negative Z direction). The donor die 102 may also be positioned rotationally with respect to each of those axes — e.g., rotated with respect to the x-axis, rotated with respect to the y-axis, rotated with respect to the z-axis. That is, the donor die 102 may be positioned by free movement in space accounted for by six different types of movement (where the movements listed above are provided as examples but where the movements may be described by other axes). Of course, the target die 104 may be positioned alone or combined with positioning of the donor die 102. Positioning or adjustment of position herein, unless the context otherwise requires, includes displacement, rotation or any combination thereof.

[0031] In some embodiments, the donor die 102 and the target die 104 may be measured with respect to a reference plane or structure (e.g., the X-Y plane), including with respect to the same reference plane or structure, but the donor die 102 or the target die 104 may be flipped (before or after measurement) so that the fabrication surface of the donor die 102 and the fabrication surface of the target die 104 may be bonded (see, e.g., the bottom diagram of Figure ID). The one or more alignment marks (e.g., the alignment marks 120 and 122) may be on the fabrication surface of the donor die 102 and the target die 104, respectively. Once the donor die 102 or the target die 104 is flipped, one or more alignment mark may be rendered invisible (such as due to opacity of a die) to an alignment measurement tool. The alignment of the flipped die may therefore be performed based on previously measured positions of the die (e.g., of the one or more alignment marks of the die) with respect to a structure, such as the donor die 102 with respect to the carrier structure 114 or such as the target die 104 with respect to the carrier structure 116.

[0032] Figures 2A-2F are schematic diagrams illustrating an example method of die placement. Figures 2A-2F are described with reference to “donor die” (and “donor substrate” containing multiple“donor die”) and “target die” (and “target substrate” containing multiple “target die”), which are relative descriptors and donor die may instead be target die and vice versa. Figures 2A-2F are described with respect to donor die and target die, but may instead be a donor substrate or target substrate, where a “substrate” may contain multiple “die”, including un-diced (e.g., unseparated) die in the form of all or part of a semiconductor wafer. Figure 2A-2F are cross-sectional views of die placement of donor dies (e.g., donor die 202A, 202B, 202C) on target dies (e.g., target die 204A and target die 204B). In some embodiments, multiple steps which are depicted as occurring substantially simultaneously in Figures 2A-2F may be performed sequentially. In some embodiments, multiple steps which are depicted as occurring sequentially in Figures 2A-2F may be performed substantially simultaneously. In some embodiments, multiple donor dies may be aligned or placed on their respective target dies substantially simultaneously, including donor dies which are proximate (including adjacent) or distant (e.g., non-adjacent but within the same target substrate). In some embodiments, steps may be performed in a different order.

[0033] Figure 2A is a cross-sectional view of donor dies 202A-202C which are to be placed on target dies 204A-204B. The donor dies 202A-202C are supported by a carrier structure 214. The donor dies 202A-202C may be adhered to the carrier structure 214 in any appropriate manner, such as by vacuum adhesion, electrostatic adhesion, intermolecular adhesion, van der Waals adhesion, mechanical interlocking, surface reaction, static friction, gravitational force, etc. The donor dies 202A-202C may be adhered to the carrier structure 214 by use of, for example, an adhesive (e.g., glue), such as an organic, polymer glue. The carrier structure 214 may be a transparent substrate, such as glass, sapphire, polymer, etc. substrate. The donor dies 202A-202C may be placed on the carrier structure 214 by any appropriate method, such as by a pick and place tool. The carrier structure 214 may be supported by a chuck or any other appropriate support structure. The carrier structure 214 may be supported (e.g., held) by a chuck (not depicted). The chuck will be described in more detail in reference to Figures 4, 5A-5C, and 6A-6G.

[0034] The target dies 204A-204B are supported by a support structure 216. In an embodiment, the target dies 204A-204B may be part of an undiced or partially diced target wafer. The target dies 204A-204B may be adhered to the support structure 216 in any appropriate manner, such as by vacuum adhesion, electrostatic adhesion, intermolecular adhesion, mechanical interlocking, surface reaction, static friction, gravitational force, etc. The target dies 204A-204B may be adhered to the support structure 216 by use of, for example, an adhesive (e.g., glue), such as an organic, polymer glue. In an embodiment, where, for example, the target dies 204A-204B are diced die, the support structure may be a carrier structure (e.g., like carrier structure 214) and may be a transparent substrate, such as glass, sapphire, polymer, etc. substrate. The target dies 204A-204B may be placed on the support structure 216 by any appropriate method, such as by a pick and place tool. The support structure 216 may be, or may be supported by, a chuck or any other appropriate structure.

[0035] The donor dies 202A-202C and the target dies 204A-204B may be aligned with one anotherat alignment points 203A and 205A (for donor die 202A and target die 204A), alignment points 203B and 205B (for donor die 202B and target die 204B), and alignment points 203C and 205C (for donor die 202C and target die 204B). In some embodiments, multiple donor die may be placed on a single target die, and vice versa, such as depending on integration goals. The alignment points 203A-203C are depicted for the donor dies 202A-202C, while the alignment points 205A-205C are depicted for the target dies 204A-204B. These alignment points are provided for ease of description only and need not be physical features. There may be multiple alignment points per die. The alignment points may be alignment marks (for example, the alignment marks of Figure ID), die edges, die comers, other features on edges or surfaces of die. The alignment points may be used to align donor and target die, such as by measurement of the locations of various alignment points and then adjustment of the position of the donor and / or target die, such as by movement of a carrier structure supporting the die, to align an alignment point of the donor die with an alignment point of the target die (or vice versa). The alignment points may be aligned directly to one another (e.g., as depicted in Figures 2A-2F). In some embodiments, the alignment points may be aligned relative to one another (e.g., in a predetermined relationship, such as separated by a vector), such as depicted in the bottom of Figure ID, where the alignment marks are non-overlapping.

[0036] In Figure 2A, the carrier structure 214 (and / or the structure 216) may be positioned, such as in the X-Y plane, in order to align the alignment point 203A of the donor die 202A with the alignment point 205A of the target die 204A.

[0037] In Figure 2B, the donor die 202A may be released from the carrier structure 214 by any appropriate mechanism, such as release mechanism 230A. The donor die 202A meets the target die 204A at alignment point 207A. The release of the donor die 202A may be facilitated by gravity, by electrostatic forces, by physical forces, etc. The alignment of the donor die 202A and the target die 204A at the alignment point 207A (which represents a combination of the alignment point 203A and the alignment point 205 A of Figure 2A) may be assisted by any appropriate alignment mechanism, including self-alignment (e.g., attraction of one area of the donor die 202A to a corresponding area of the target die 204A). In an embodiment, the release occurs while donor die 202A is in (at least partial) contact with target die 204A. In an embodiment, the release occurs before donor die 202A is in contact with the target die 204 A.

[0038] In Figure 2C, the carrier structure 214 (and alternately or additionally the structure 216) may be moved to bring another donor die (e.g., the donor die 202C) into alignment with another target die (e.g., the target die 204B). The alignment of alignment point 203 C (of donor die 202C) and alignment point 205 C (of target die 204B) may be based on measurements of the relative positions of the alignment points (such as using an alignment mark or feature on a die or carrier structure, using a position of an alignment point on another donor or target die, etc.). The alignment of alignment point 203 C (of donor die 202C) and alignment point 205 C (of target die 204B) may be based on one or more substantially simultaneous measurement of the relative positions of an alignment point, such asusing an alignment mark or feature of a die or carrier structure, using an alignment target or feature of another donor or target die, etc. Although alignment of only one donor die (e.g., the donor die 202C) and target die (e.g., the target die 204B) is depicted, alignment of one or more sets of donor and target dies may occur substantially simultaneously, such as if for a given relative position of the carrier structure 214 and the support structure 216 the alignment points of multiple donor dies are aligned with the alignment points of multiple target dies. However, the ability to place multiple donor dies substantially simultaneously may depend on the placement of the donor dies on the carrier structure 214 and the ability of the release mechanism to release multiple donor dies.

[0039] In Figure 2D, the donor die 202C may be released from the carrier structure 214 by any appropriate mechanism, such as release mechanism 230C. The donor die 202C meets the target die 204B at alignment point 207C. The release of the donor die 202C may be facilitated by gravity, by electrostatic forces, by physical forces, etc. The alignment of the donor die 202C and the target die 204B at the alignment point 207C (which represents a combination of the alignment point 203 C and the alignment point 205C of Figure 2A) may be assisted by any appropriate alignment mechanism, including self-alignment. In an embodiment, the release occurs while donor die 202B is in (at least partial) contact with target die 204B. In an embodiment, the release occurs before donor die 202B is in contact with the target die 204B.

[0040] In Figure 2E, the carrier structure 214 (and alternately or additionally the structure 216) may be moved to bring another donor die (e.g., the donor die 202B) into alignment with another target die (e.g., the target die 204B). The alignment of alignment point 203B (of donor die 202B) and alignment point 205B (of target die 204B) may be based on previous measurements of the relative positions of the alignment points (such as using an alignment mark on a die or carrier structure, using an alignment point on another donor or target die, etc.). The alignment of alignment point 203B (of donor die 202B) and alignment point 205B (of target die 204B) may be based on one or more substantially simultaneous measurement of the relative positions of an alignment point, such as using an alignment mark or feature of a die or carrier structure, using an alignment target or feature of another donor or target die, etc. As depicted, the donor die 202B and the donor die 202C are aligned to the same target die (e.g., the target die 204B). In some embodiments, the donor die are placed on the target die in a substantially one-to-one relationship (e.g., as depicted for the donor die 202A and the target die 204A). In some embodiments, multiple donor die (or target die) may be placed on the same target die (or donor die). In some embodiments, multiple donor die (or target die) may be placed on un-diced (e.g., unseparated) target die (or donor die), such as all or part of a substrate containing target die (or donor die). In some embodiments, a donor die may be placed on a target die that has multiple die, including stacked (e.g., bonded) die, such as in a three layer die bonding stack.

[0041] In Figure 2F, the donor die 202B may be released from the carrier structure 214 by any appropriate mechanism, such as release mechanism 230B. The donor die 202B meets the target die 204B at alignment point 207B. The release of the donor die 202B may be facilitated by gravity, byelectrostatic forces, by physical forces, etc. The alignment of the donor die 202B and the target die 204B at the alignment point 207B (which represents a combination of the alignment point 203B and the alignment point 205B of Figure 2A) may be assisted by any appropriate alignment mechanism, including self-alignment. In an embodiment, the release occurs while donor die 202B is in (at least partial) contact with target die 204B. In an embodiment, the release occurs before donor die 202B is in contact with the target die 204B.

[0042] Figures 3A-3J are schematic diagrams illustrating portions of an example apparatus for die bonding. Figures 3A-3J are described with reference to “donor die” and “target die”, which are relative descriptors as used herein and donor die may instead be target die and vice versa. Each of Figures 3A, 3C, 3E, 3G, and 31 is a plane view of an apparatus during placement of donor die on the target die. Each of Figures 3B, 3D, 3F, 3H, and 3 J is a cross-sectional view of the apparatus during placement of donor die on the target die. The views of the apparatus in various figures represent different operations of the apparatus, but operations depicted as occurring in different figures may occur at different times or may instead be performed simultaneously and operations depicted as occurring in the same figure may instead be performed individually or at different times. A donor substrate 300 and a target substrate 350 are depicted as circular, but may instead be any appropriate shape, including rectangular, square, etc. The donor substrate 300 (and target substrate 350) may be the substrate in or on which the donor die (target die) have been formed. The donor substrate 300 (target substrate 350) may be a “reconstructed wafer”, in which donor die (target die) (or other disparate portions of a semiconductor substrate) are arranged or supported on a carrier structure, e.g., to be in position suitable for die bonding. So, the donor substrate 300 (target substrate 350) may be a carrier structure and donor die (target die), where the donor die (target die) may be held (e.g., adhered) to the carrier structure by any appropriate method, such as by gravitational force, by adhesive (e.g., organic, polymer adhesive), by electrostatic forces, etc. The donor substrate 300 (target substrate 350) may contain previously tested donor die (target die), such as donor die (target die) that passed a failure analysis or other post fabrication testing. The donor substrate 300 (target substrate 350) may contain donor die (target die) from the same or different semiconductor substrates (e.g., fabrication substrates), including donor die (target die) of different types, different dimensions, etc. The donor substrate 300 (target substrate 350) may have donor die (target die) placed on the donor substrate 300 (target substrate 350) by any appropriate method, such as a pick and place tool. The donor substrate 300 (target substrate 350) may be supported, such as by a carrier structure, chuck (e.g., vacuum chuck, electrostatic chuck, mechanical chuck, etc.,) or any other appropriate support structure by either a top side (e.g., fabrication face) or backside (e.g., bulk substrate or carrier structure face) or by different faces at various points. The donor substrate 300 or donor die (target substrate 350 or target die) may have fabricated devices on multiple faces, such as through silicon vias (TSVs), contact pads, etc., such that both a top side and backside are fabrication faces.

[0043] In Figure 3A, the donor substrate 300 may be placed on a substrate chuck 320A. The substratechuck 320A may be an appropriate substrate chuck, such as to support the donor substrate 300 in the form of a semiconductor substrate or a carrier structure of the donor substrate 300. The substrate chuck 320A may or may not be transparent to radiation (e.g., light). The substrate chuck 320A may be supported by a support structure 322A. The support structure 322 A may be a moveable support structure, which may move in the X-Y plane, such as from a first position where the substrate chuck 320A receives the donor substrate 300 to a second position where the donor substrate 300 may be subjected to metrology. The substrate chuck 320A may contain (e.g., support) one or more die actuators or other mechanical or electrical actuators which may move a donor die or the donor substrate 300 in one or more dimension, including in the X-Y plane, in the Z-direction, rotationally, etc. The substrate chuck 320A may have one or more alignment marks, such as to allow a camera or other measurement system to track the position of the substrate chuck 320A. The substrate chuck 320A may have multiple sets of alignment marks, such as coarse alignment marks and / or fine alignment marks. The substrate chuck 320A may move, such as by action of the support structure 322A, from one position to another, in free space, etc. The support structure 322A may be configured to move in multiple directions and in multiple scales (e.g., in a coarse step and a fine step), such as by multiple motors or steppers. The support structure 322 A may be activated by a controller of the example apparatus — where the controller of the example apparatus (not depicted) may also control the placement of the donor substrate 300 on the substrate chuck 320A and other operations described herein.

[0044] The substrate chuck 320A may have a measurement point (or alignment point), such as identified by a cruciform measurement mark 327 and a round zero measurement mark 328, which are provided merely as examples and where any appropriate zero measurement mark may be used. The measurement point may be used to place the donor substrate 300 on the substrate chuck 320A, such as during movement of the substrate onto the chuck (for example, by insertion of the donor substrate by a substrate handler). The measurement point may be used to measure relative positions of the donor die of the donor substrate 300 once the donor substrate 300 is placed on the substrate chuck 320A. The placement of the donor die may be measured, such as with up to nm precision, with respect to the measurement point. The measurement of the position of the donor die after their placement may be obtained from any appropriate measurement system, such as optical microscopy, reflectometry, etc.

[0045] Figure 3A also depicts a further substrate chuck 320B on a support structure 322B. The substrate chuck 320B may be any appropriate substrate chuck, such as substantially identical to the substrate chuck 320A. The support structure 322B may be any appropriate support structure, such as substantially identical to the support structure 322A. In some embodiments, the substrate chuck 320B and the substrate chuck 320A may be substantially indistinguishable. In some embodiments, the support structure 322B and the support structure 322A may be substantially indistinguishable. Although two substrate chucks and two support structures are depicted, in some embodiments more or less substrate chucks and support structures may be present in the apparatus. Operations depicted asperformed by the substrate chuck 320B (substrate chuck 320A) may instead or additionally be performed by any appropriate substrate chuck. Likewise, operations depicted as performed by the support structure 322B (support structure 322A) may instead or additionally be performed by any appropriate support structure.

[0046] Figure 3A also depicts flipper 330. The flipper 330 may be any appropriate apparatus which may flip a substrate (e.g., donor substrate 300), such as about the longitudinal axis or plane of the donor substrate 300 depicted in Figure 3A. The flipper 330 will be described in more detail in reference to Figures 3E and 3F.

[0047] In Figure 3B, a cross-sectional view of a donor substrate 300 is depicted. The donor substrate 300 comprises a carrier structure 314 which supports one or more donor die (e.g., donor die 302A- 302C). The substrate may have one or more alignment points, such as alignment point 315, used to measure a relative position of the donor die 302A-302C with respect to the carrier structure. The donor die may have alignment points, such as alignment points 303A-303C for donor die 302A-302C, respectively. The alignment points are provided as schematic representations in these drawings for ease of description, and may be any appropriate alignment points, including alignment marks, fabricated features, edge features, etc., as previously described. While the donor substrate 300 is on a substrate chuck (e.g., the substrate chuck 320A of Figure 3A), the positions of the donor die (e.g., the donor die 302A-302C) are measured, such as by metrology tool 340A. The positions may be measured as absolute positions, relative positions, positions relative to other die, positions relative to an alignment point of the substrate, etc. The measured positions may be stored by a controller of the apparatus, such as for later positioning of the donor substrate 300. The metrology tool 340A may be a camera, including a still camera, a video camera, etc. The metrology tool 340A may be any appropriate tool for measurement of a position of a donor die, measurement of a position of an alignment point of the donor die, measurement of a position of alignment mark of the donor die, etc.

[0048] In Figure 3C, the donor substrate 300 is supported by the substrate chuck 320A, which is supported by the support structure 322A. Once the position of the donor dies are measured, the substrate chuck 320A may be moved, such as out of the measurement position. The support structure 322A may move (e.g., along direction 324) to the position of the support structure 322B, while the support structure 322B may move (e.g., along direction 323) to the position of the support structure 322A. The positions are provided as examples, and the support structures may move to different positions. For example, in some embodiments, the support structure 322B may move to a loading position, such as to receive a target substrate (e.g., the target substrate 350). The substrate chuck 320A may then occupy another position in the apparatus (e.g., a bonding position, a flipping position, etc.). The position the substrate chuck 320A moves to after measurement of the positions of the donor die (e.g., after the measurement depicted in Figure 3B) may be configured to allow the flipper 330 to accept the donor substrate 300 from the substrate chuck 320A.

[0049] In Figure 3D, the movement of the donor substrate 300 to a position other than themeasurement position of Figure 3B is depicted. The movement may correspond to the movement of the donor substrate 300 in the direction 324, such as by movement of the support structure 322A, of Figure 3C. This figure is provided to show continuity of the die bonding process in both plane and cross-sectional views, but may occur substantially simultaneously with the process depicted in Figure 3C or Figure 3E, where, as previously described, steps which are depicted as occurring separately, including sequentially, may be performed substantially simultaneously.

[0050] In Figure 3E, the target substrate 350 may be placed on a substrate chuck 320B. The substrate chuck 320B may be an appropriate substrate chuck, as previously described. The substrate chuck may be supported by a support structure 322B, which may be any appropriate support structure, as previously described.

[0051] In Figure 3E, the donor substrate 300 may be transferred to the flipper 330. The flipper 330 may accept (e.g., take) the donor substrate from the substrate chuck 320A, such as by use of edge clamps, vacuum clamps, finger prongs, etc. The flipper 330 may hold the donor substrate by one or more edges (e.g., one or more edges of the carrier structure 314) or one or more sides (for example, a backside of the carrier structure 314 which does not support the donor die). The flipper 330 may rotate the donor substrate 300 upside down (e.g., with respect to the direction of the gravitational force). The flipper 330 may hold the donor substrate 300 upside down (e.g., opposite to) with respect to the X-Y plane which it previously occupied — or in any other appropriate direction. The flipper 330 may hold the donor substrate 300 or place the donor substrate 300 into a support structure, such that the donor substrate 300 faces the plane of the target substrate 350. The flipper 330 may rotate or displace the donor substrate 300 in the X-Y plane, as well as displace or rotate the donor substrate 300 out of the X-Y plane. The flipper 330 may be any appropriate rotational or translational apparatus.

[0052] In Figure 3F, a cross-sectional view of the target substrate 350 is depicted. The target substrate 350 comprises a carrier structure 316 which supports one or more target dies (e.g., target die 304A-304C). The substrate may have one or more alignment points, such as alignment point 317. The target die may have alignment points, such as alignment points 305A-305C for target die 304A-304C, respectively. The alignment points are provided as schematic representations in these drawings for ease of description, and may be any appropriate alignment points, including alignment marks, fabricated features, edge features, etc., as previously described. While the target substrate 350 is on the substrate chuck (e.g., the substrate chuck 320B of Figure 3E), the positions of the one or more target dies (e.g., the target die 304A-304C) are measured, such as by metrology tool 340B. The metrology tool 340B may be the same as the metrology tool 340A used to measure the positions of the one or more donor dies (e.g., the donor die 302A-302C of Figure 3B) or a different metrology tool. The metrology tool 340B may measure a different number of positions, substantially different positions (e.g., arranged differently on the target substrate 300 than the positions on the donor substrate 300 as measured by the metrology tool 340A), different positions relative to dies (e.g., the donor die 302A-302C versus the target die 304A-304C), etc. than the metrology tool 340A. Thepositions may be measured as absolute positions, relative positions, positions relative to other die, positions relative to an alignment point of the substrate, etc. The measured positions may be stored by a controller of the apparatus, such as for later positioning of the target substrate 350. The metrology tool 340B may be a camera, including a still camera, a video camera, etc. The metrology tool 340B may be any appropriate tool for measurement of a position of a donor die, measurement of a position of an alignment point of the donor die, measurement of a position of alignment mark of the donor die, etc. The target substrate 350 may experience deformation due to the holding by a substrate chuck, etc. The metrology tool 340B may also enable determination of deformation of the target substrate by measuring locations. A controller may determine the deformation of the target substrate 350 based on those measured locations (e.g., from curve fitting, using a physical deformation model, etc.).

[0053] In Figure 3F, the donor substrate 300 is supported by a bonding support structure 332 (e.g., a chuck for holding the donor substrate 300 for bonding). The bonding support structure 332 may be part of the flipper 330 (of Figure 3E) or the donor substrate 300 may be placed into the bonding support structure 332 by the flipper 330. The bonding support structure 332 may hold the donor substrate 300 opposite to a plane of the target substrate 350. The bonding support structure 332 may hold the donor substrate by the carrier structure 314, including by one or more edges of the carrier structure 314. The bonding structure 332 may hold the donor substrate by the carrier structure 314 by any appropriate method. In one or more embodiments, the bonding support structure 332 may be a chuck as described in more detail in reference to the embodiments of Figures 4, 5A-5C, and 6A-6G. While in the bonding support structure 332, the position of the donor substrate 300 may be measured, such as by metrology tool 340C, to enable, for example, relative positioning between the donor substrate 300 and the target substrate 350. The metrology tool 340C may be any appropriate metrology tool. The metrology tool 340C may measure locations of the donor die (e.g., the donor die 302A-302C), locations of the alignment point 315, etc. The metrology tool 340C may measure significantly fewer locations than the metrology tool 340A or 340B, and the controller may determine the position of the target substrate 350 based on those fewer locations (e.g., from curve fitting, using physical deformation models, etc.). The controller may determine updated positions for the donor die (e.g., the donor die 302A-302C) based on a combination of the measured locations of the donor die 302A-302C (such as from Figure 3B) and the measured position of the donor substrate 300. The donor substrate 300 may experience deformation due to holding by a substrate chuck, the movement of the flipper 330, suspension from the bonding support structure 332, etc. The metrology tool 340C may also enable determination of deformation of the donor substrate by measuring locations. As noted above, the metrology tool 340C may measure significantly fewer locations than the metrology tools 340A and 340B, and the controller may determine the deformation of the donor substrate 300 based on those fewer locations (e.g., from curve fitting, using a physical deformation model, etc.) than those measured by the metrology tool 340A on the donor substrate 300 or by metrology tool 340B on the target substrate 350.

[0054] In Figure 3G, the target substrate 350 is supported by the substrate chuck 320B, which is supported by the support structure 322B. Once the position of the target dies are measured, the substrate chuck 320B may be moved, such as to align with the donor substrate 300 supported by the flipper (e.g., supported by the bonding support structure 332 of Figure 3F). The support structure 322B may move (e.g., along direction 326) to the position of the support structure 322A, while the support structure 322A may move (e.g., along direction 325) to the position of the support structure 322B. The positions are provided as examples, and the support structures may move to different positions. For example, in some embodiments, the support structure 322A may move to a loading position, such as to receive an additional target substrate (e.g., the target substrate 350). The substrate chuck 320B may then occupy another position in the apparatus (e.g., a bonding position). The position the substrate chuck 320B moves to after measurement of the positions of the target die (e.g., after the measurement depicted in Figure 3F) may be configured to place a donor die of the donor substrate 300 onto the target die of the target substrate 350. The substrate chuck 320B may be aligned with the donor substrate 300 in the flipper 330, which may be held above the plane of the substrate chuck 320B (as depicted in Figure 3G for a top down view in which the donor substrate 300 is at least partially above the plane of the substrate chuck 320B (e.g., obscuring the substrate chuck 320A).

[0055] In Figure 3H, the donor substrate 300 and the target substrate 350 are aligned. The donor substrate 300 may be aligned to the target substrate 350 by movement of the bonding support structure 332, which may be a chuck as described in more detail in reference to the embodiments of Figures 4, 5A-5C, and 6A-6G, such as in any of the directions or orientations 333. The target substrate 350 may be aligned with the donor substrate 300 by movement of a substrate chuck (e.g., the substrate chuck 320B of Figure 3G) or the support structure (e.g., the support structure 322B of Figure 3G). The donor substrate 300 and the target substrate 350 may be aligned to one another, including by both coarse and fine alignment, such as by alignment of the relative positions of one or more alignment point (e.g., the alignment point 315 of the donor substrate 300 and the alignment point 317 of the target substrate 350). In some embodiments, the donor substrate 300 and the target substrate 350 may be aligned, such as by coarse alignment. In some embodiments, once the donor substrate 300 and the target substrate 350 are aligned, one or more donor die of the donor substrate 300 may be aligned with one or more target die of the target substrate 350. In Figure 3H, the alignment of the donor die 302B with the target die 304B (e.g., of the alignment point 303B of donor die 302B with the alignment point 305B of target die 304B) is depicted. Once a donor die is aligned with a target die, that donor die may be placed on the target die, by any appropriate method, such as die actuator activation, gravitational acceleration, electrostatic actuation, etc.

[0056] In Figure 31, an additional donor substrate (e.g., donor substrate 300-2 having a carrier structure 314-2) is placed on the substrate chuck 320A for additional placement of donor dies on target dies. In some embodiments, the additional donor substrate may be placed on the substrate chuck 320A after the substrate of the previous donor substrate is removed from the substrate chuck 320A —for example, if the substrate of a donor substrate is removed from the flipper 330 and re-placed on the substrate chuck 320A. In some embodiments, the previous donor substrate may be removed from the flipper 330 without recourse to the substrate chuck 320A, such as by removal from the flipper to an additional substrate chuck (not depicted) or any other appropriate removal procedure. The additional donor substrate may be placed on the substrate chuck 320A after the previous donor substrate is accepted by the flipper 330 or at any time when the substrate chuck 320A (or another substrate chuck) is free. The additional donor substrate (e.g., the donor substrate 300-2) may be substantially identical to or different from the previous donor substrate (e.g., the donor substrate 300). The processing of the donor substrate 300-2 by placement of the donor dies on target dies may proceed as previously described in relation to Figures 3A-3H, such as by placement on an additional target substrate (not depicted). The donor substrate 300-2 may be placed on the substrate chuck 320A while the donor dies of the donor substrate 300 are placed on the target dies of the target substrate 350, such as substantially simultaneously.

[0057] In Figure 3J, the positions of the donor die (e.g., the donor die 302A-2 to 302C-2) and / or of mark 315-2 are measured, as previously described in relation to Figure 3B.

[0058] In Figure 3J, additional donor die of the donor substrate 300 are placed on the target die of the target substrate 350. The position of the donor substrate 300, the target substrate 350, or a combination thereof may be adjusted to align an additional donor die of the donor substrate 300 with a target die of the target substrate 350. As depicted, the donor substrate 300 is positioned (such as by movement in the directions or orientations 334) to align the alignment point 303A of the donor die 302A with the alignment point 305A of the target die 304A. The donor die 302A may then be placed on the target die 304A by any appropriate method, such as previously described. The donor die 302B is depicted as bonded to the target die 304B, subsequent to their alignment at alignment point 307B in Figure 3H. As will be realized, the various steps of Figures 3A-H can be repeated as appropriate to bond multiple dies and process multiple donor and target substrates.

[0059] Additionally, after the donor die 302A-302C are placed on the target die 304A-304C, the carrier substrate 314 (which may no long hold a substantial number of donor die) may be removed from the bonding support structure 332 by any appropriate means, such as those described in further detail in reference to Figures 6F-6G. The carrier substrate 314 may be removed to the flipper 300 or any other appropriate location.

[0060] Various techniques of holding / securing a die are described hereafter. Those techniques are described with reference to “donor die” and “target die”, which are relative descriptors as used herein and donor die may instead be target die and vice versa. A donor die may instead be a donor substrate and / or a target die may instead be a target substrate. A donor die may be bonded to a target substrate, a donor substrate may be bonded to a target substrate, or a donor substrate may be bonded to a target die. Multiple donor dies may be bonded to a single target die and vice versa. The die holding / securing techniques are described, for example, with respect to use of a carrier structure (e.g., carrier structure414) to hold a donor die. As will be appreciated, the die holding / securing techniques are not limited to use with a carrier structure or limited to use with a donor die. For example, additionally or alternatively, the die holding / securing techniques may be used with an individual die, may be used with a wafer having undiced dies, etc. Additionally or alternatively, where appropriate and suitably configured, the die holding / securing techniques may be used with, for example, a target die (such as an individual target die, a wafer having undiced target dies, etc.).

[0061] Figure 4 is a schematic diagram illustrating an example edge holding method of securing a die. Figure 4 is a cross-sectional view of bonding of a donor die (e.g., donor die 402) to a target die (e.g., target die 404).

[0062] In Figure 4, donor dies 402 are supported by a carrier structure 414. The carrier structure 414 is transparent to at least a range of radiation (e.g., electromagnetic radiation, visible light, UV radiation, a particle or electron beam, etc.). The carrier structure 414 may be fully transparent, partially transparent (e.g., at least 99% transparent, at least 95% transparent, at least 90% transparent, at least 80% transparent, at least 50% transparent, etc.), intermittently transparent (for example, transparent in areas on which donor die 402 are placed), etc. “Transparency” (and its grammatical conjugates) as used herein does not require that 100% of radiation intensity be passed through a material, but rather that a substantial or significant portion of radiation (e.g., at least 25%, at least 50%, at least 80%, at least 90%, at least 95%, etc.) pass through the material for at least a range of wavelengths. In an illustrative example, a salt plate may be considered transparent to near infrared (near IR) radiation, although it is not 100% transparent to radiation over the entire near IR range (e.g., in an IR spectroscopy range between 40 and 13,000 cm1, a salt plate may have significant absorption at 400 and 600 cm'1and still be considered transparent to near IR). Likewise, a material may be considered transparent over a wavelength range in which it may have even fully absorptive peaks and / or bands. The carrier structure 414 may be transparent to visible light, infrared radiation, ultraviolet radiation, a particle or electron beam, etc. The carrier structure 414 may be fabricated of any appropriate material, such as glass, silicon dioxide, sapphire, acrylic, etc. The carrier structure 414 may be fabricated of a material with any appropriate atomic structure — e.g., crystalline, semicrystalline, amorphous, plastic, etc. The carrier structure 414 may be a flexible substrate, such as a flexible polymer supported by a superstructure (such as a superstructure with one or more radiation windows). The carrier structure 414 may be a substantially inflexible substrate. The thickness of the carrier structure 414 (e.g., in the Z direction) may vary depending on which type of material the carrier structure 414 is fabricated from, such as where thickness may be selected based on deformation thresholds, electromagnetic radiation extinction coefficients, etc.

[0063] The carrier structure 414 may have any properties or be used to perform any function previously described in reference to the carrier structure 114 (or carrier structure 116) of Figures 1A- 1D, carrier structure 214 (or carrier structure 216) of Figures 2A-2F, carrier structure 314, carrier structure 316, or carrier structure 314-2 of Figures 3A-3J).

[0064] In an embodiment, a donor die 402 is adhered to the carrier structure 414 by, e.g., a layer of adhesive. Herein, “adhered” encompasses holding of one material to another in a manner which is releasable, including where the release is chemically, physically, electrically, etc. mediated. The adhesive may be any appropriate adhesive, such as an organic glue, a polymer glue, etc. The adhesive may be applied to the carrier structure 414 (such as by spin coating) and then the donor die 402 applied to the adhesive on the substrate. The adhesive may be applied to a surface of the donor die 402 (such as by ink jetting, dipping, etc.) and then the donor die 402 and adhesive transferred to the carrier structure 414. The adhesive may be of any appropriate thickness.

[0065] The adhesive may be an adhesive which forms a gas when exposed to radiation or heat. For example, the adhesive may be an adhesive which experiences a phase change (such as at atmospheric temperature and pressure) from solid or liquid to gas when excited by a burst of radiation or heated by such a burst of radiation. The adhesive may be an adhesive which experiences a chemical change (such as a decomposition) which forms gas when excited by a burst of radiation or heated by such a burst. In some embodiments, the adhesive may expand in volume without forming a gas or only partially forming a gas when exposed to radiation or heat. For example, the adhesive may contain a dissolved gas which may partially precipitate when exposed to radiation or heat and which may create bubbles within the adhesive thereby increasing the volume occupied by the adhesive. The adhesive may be any appropriate material which experiences radiation-mediated volume expansion. The volumetric expansion of the adhesive may cause release of the donor die 402 from the carrier structure 414 and towards (e.g., in the direction 430) the target die 404 on a carrier structure 416 (such as carrier structure holding dies, a wafer with undiced dies, etc.) The radiation-mediated placement of the donor die 402 on the target die 404 may enable die bonding, as previously described.

[0066] The radiation which is supplied to cause the expansion of the adhesive may be supplied by a radiation source 442 through the carrier structure 414. Although the source 442 is depicted as an incandescent bulb, any appropriate radiation source may be used, such as a broadband light source (e.g., white light), a light emitting diode (LED), a laser, etc. The source 442 may have provide radiation with any appropriate wavelength and wavelength range (e.g., bandwidth). The source 442 may have any appropriate spot size. In some embodiments, the source 442 may expose an area smaller than the area of a donor die 402 at a time, such as for selection of one donor die at a time for release. In some embodiments, the source 442 may have a larger spot size and may be focused, such as by focusing optics (not depicted) at the adhesive on the backside of one donor die at a time. In some embodiments, the source 442 may be focused on different donor dies 402 at different times (such as when they are aligned with respective target die 404) in order to release those one or more donor dies 402 which are aligned at any given position of the carrier structure 414 relative to the one or more target die 404. In some embodiments, there may be relative movement, such as in direction 444, between the radiation and the adhesive of the donor die 402 in order to release the donor die 402 for die bonding. For example, source 442 may sweep the radiation across, such as in direction 444, thecarrier structure 414. In an embodiment, the source 442 itself may move in direction 444. In an embodiment, the source 442 comprises optics (not depicted) to cause the relative movement. In an embodiment, the relative movement can be created in part by movement of the carrier structure 414. The carrier structure 414 may be at least partially transparent to radiation of a wavelength (or range of wavelengths) which causes radiation-mediated volume expansion in the adhesive. The radiation of the source 442 may penetrate through the carrier structure 414 to reach the adhesive on the backside of the donor die 402 in order to cause radiation -mediated release (and bonding) of the donor die 402.

[0067] The carrier structure 414 may be supported, e.g., held, by a chuck 432. In some embodiments, the chuck 432 may have properties or be used to perform any function previously described in reference to Figures 1A-1D, Figures 2A-2F, and substrate chuck 32A, substrate chuck 320B, or bonding support structure 322 of Figures 3A-3J. In some embodiments, the chuck 432 may have properties or be used to perform any function previously described as corresponding to the support structure 322A, support structure 322B, or flipper 300 of Figures 3A-3J. The carrier structure 414 may be supported on the chuck 432 by vacuum adhesion, electrostatic adhesion, intermolecular adhesion, van der Waals adhesion, mechanical interlocking, surface reaction, static friction, gravitational force, etc.

[0068] The chuck 432 is depicted as having a body extending along the x-y plane, where a first face of the chuck body meets a first face of the carrier structure 414. The chuck 432 is also depicted as having one or more sidewalls which extend down from the body in the negative z direction. This depiction is for illustrative purposes only, and the chuck body may instead be substantially planar. The chuck 432 may instead or additionally have one or more recessed areas, including a recessed area for acceptance of at least part of the carrier structure 414. The chuck 432 may have one or more additional structures on the backside (e.g., the side opposite the first face which holds the carrier structure 414), such as one or more connection points, one or more struts which secure the chuck 432 to a tool body or other support structure, one or more mechanical steppers or other actuators, one or more mechanical arms, etc. As these additional structures may be any appropriate structures and have a wide variety of configurations, they are not depicted in Figure 4.

[0069] The chuck 432 is transparent in part to at least a range of radiation (e.g., electromagnetic radiation, visible light, UV radiation, a particle or electron beam, etc.). The chuck 432 may be fully transparent, partially transparent (e.g., at least 99% transparent, at least 95% transparent, at least 90% transparent, at least 80% transparent, at least 50% transparent, etc.), intermittently transparent (for example, transparent in areas corresponding to the donor die 402), etc. The chuck 432 may be transparent to visible light, infrared radiation, ultraviolet radiation, a particle or electron beam, etc. In the embodiment depicted in Figure 4, the chuck 432 is transparent to a range of radiation in the window 440. The window 440 may be made of the same or a different material than the rest of the body of the chuck 432. The window 440 may be substantially the same size as or larger than the carrier structure 414. In some embodiments, the window 440 may be smaller than the carrier structure414, or comprise a set of windows (as will be described in relation to Figure 5A). The chuck 432 may be relatively opaque to radiation other than in the window 440. The chuck may be transparent to radiation in other regions in addition to the window 440. The window 440 of the chuck 432 may be transparent to the same one or more wavelengths of radiation as the carrier structure 414 (such as if the carrier structure 414 and the window 440 are fabricated of substantially the same material), to a set of one or more wavelengths of radiation within the range that the carrier structure 414 is transparent to (e.g., to a subset of one or more wavelengths which pass through the carrier structure 414), to one or more wavelengths which the carrier structure 414 is not transparent to. That is, the window 440 may have an overlapping but not identical transparency range with the carrier structure 414. For example, the carrier structure 414 may be transparent to a larger range of wavelengths inclusive of the range of wavelengths to which the window 440 is transparent, or vice versa. The window 440 may extend through the body of the chuck 432 (e.g., from the top of the chuck to the bottom of the chuck, as depicted) in the direction of radiation exposure. The face of the chuck 432 to which the carrier structure 414 is held may consist substantially of the window 440.

[0070] The body of the chuck 432 and the window 440 may be constructed of the same or different materials. For example, the body of the chuck 432 may be constructed of aluminum while the window 440 may be constructed of silicon dioxide. The body of the chuck 432 and the window 440 may be constructed of substantially the same material, but with different absorptive properties. For example, the window 440 may be fabricated of a transparent polymer, such as plexiglass, while the body of the chuck 432 may be constructed of a non-transparent (for example, dyed) version of the same polymer, such as an opaque plexiglass. The window 440 may be fabricated of any appropriate material, such as glass, silicon dioxide, sapphire, acrylic, etc. The window 440 may be fabricated of a material with any appropriate atomic structure - e.g., crystalline, semi-crystalline, amorphous, plastic, etc. The window 440 may be constructed of a rigid material. The window 440 may be constructed of flexible material, including a flexible material supported by a rigid superstructure (such as a wire or mesh superstructure with is at least partially transparent to radiation). The window 440 may be substantially inflexible. The thickness of the window 440 (e.g., in the Z direction) may vary depending on which type of material the window 440 is fabricated from, such as where thickness may be selected based on rigidity, deformation thresholds, electromagnetic radiation extinction coefficients, etc. The body of the chuck 432 may be fabricated of any appropriate material, such as metal, plastic (e.g., hard plastic), glass, silicon dioxide, sapphire, polymer, etc. The body of the chuck 432 may be constructed of a rigid material. The body of the chuck 432 may be additively or subtractively formed by any appropriate machining process, such as milling, casting, 3D printing, etc. The body of the chuck 432 may be fabricated and an opening formed for the window 440. The window 440 may be held into the body of the chuck 432 by any appropriate fastening mechanism, such as glue, a clamp, etc.

[0071] The radiation of the source 442 may penetrate through the chuck 432 (e.g., through the window 440 of the chuck 432) to reach the carrier structure 414 and through both the chuck 432 andthe carrier structure 414 to reach the adhesive on the backside of the donor die 402. The transmission of the radiation through the window 440 and the carrier structure 414 may be better controlled if the carrier structure 414 is held closely to the chuck 432. For example, the transmission of radiation through the chuck 432 and the carrier structure 414 may be variable (e.g., vary in intensity, vary in angle of incidence, etc.) if the carrier structure 414 is bowed, tilted, etc., with respect to the chuck 432. By holding the carrier structure 414 flat against the chuck 432, any intervening distorting elements (e.g., air, reflective planes, etc.) may be reduced or removed. For example, bowing of the carrier structure may cause a gas gap between the chuck 432 and the carrier structure 404, which may introduce planes of varying refractive index (e.g., the face of the window 440 and the carrier structure 404 with air) which may cause reflectance or other distortion of transmitted radiation. In some embodiments, therefore, it may be desirable to help ensure that the carrier structure 414 is held against the chuck 432 while also ensuring that radiation may be transmitted through the chuck 432 to reach the carrier structure 414. As most traditional methods of chuck clamping (e.g., electrostatic clamping, vacuum clamping, etc.) involve substantially opaque materials, methods of transparent chucking are presented in multiple embodiments.

[0072] The carrier structure 414 may be held on the window 440 of the chuck 432. In an embodiment, the chuck 432 uses a mechanical means, such as an edge restraining mechanism, to hold or limit movement of the carrier structure. The edge restraining mechanism may include one or more edge restraining mechanisms 450A, 450B. The edge restraining mechanisms 450A, 450B may attach to or engage with one or more edges (e.g., short face) of the carrier structure 414. The edge restraining mechanisms 450A, 450B may comprise an arm 454A, 454B and an edge engaging structure 452A, 452B. Although two edge restraining mechanisms 450A, 450B are depicted, more may be used. In some embodiments, one edge restraining mechanism may be used, such as to push against the carrier structure 414 and hold it against a sidewall of the chuck 432. In other embodiments, multiple edge restraining mechanisms may be used, including arranged symmetrically about the one or more edges of the carrier structure 414 (for example, equally spaced about the one or more edges of the carrier structure 414). In an embodiment, the arms 454A, 454B, may extend or move by any appropriate means, such as a screw extension or movement, a scissor extension or movement, hinged extension or movement, actuator extension or movement, etc. The structures 452A, 452B may have any appropriate surface geometry to conform to the edge of the carrier structure 414. For example, the carrier structure 414 may have a notch into which the structures 452A, 452B may fit. The arms 454A, 454B are depicted as extending out of the sidewalls of the body of the chuck 432. In some embodiments, the arms 454A, 454B may instead or additionally extend from anchor points on the face of the chuck 432 (including if the chuck 432 is substantially planar).

[0073] The chuck 432 is depicted as holding the carrier structure 414 up (e.g., opposite the direction of gravity). The chuck 432 may instead hold the carrier structure 414 in any other direction, such as down (e.g., with the direction of gravity), perpendicular to the direction of gravity (e.g., with thecarrier structure 414 facing the in the positive or negative x or y direction as depicted), at an oblique angle with respect to gravity (e.g., with the carrier structure 414 inclined with respect to gravity), etc.

[0074] In some embodiments, the edge restraining mechanisms 450A, 450B may hold or restrain the carrier structure 414 in place in the x-y plane, but may not hold or restrain the carrier structure 414 with respect to the z direction. In some embodiments, the edge restraining mechanisms 450A, 450B may be combined with one or more additional methods for securing the carrier structure 414 to the chuck 432, such as with a mechanism that holds the carrier structure 414 to the chuck 432 in place in the z-direction. In some embodiments, the edge restraining mechanism 450A, 450B may hold the carrier structure in place, at least partially, in the z-direction but may not provide sufficient holding power (or sufficient holding power in the center of the carrier structure 414 so as to avoid bowing). In some embodiments, the edge restraining mechanism 450A, 450B, may be combined with one or more additional mechanisms, such as a mechanism providing holding power near a central portion of the carrier structure 414, in order to prevent bowing or other distortions. In some embodiments, one or more mechanisms may be combined in order to hold the carrier structure 414 against the chuck 432 without substantial movement (e.g., in place) even as the chuck 432 is moved (for example, in the x-y plane to align one or more donor dies 402 with one or more target dies 404 or in the z direction to place a donor die 402 on a target die 404). In an embodiment, the edge restraining mechanism 450A, 450B is one or more kinematic mounts to engage one or more edges of the carrier for restraining movement of the carrier with respect to the chuck. For example, the edge restraining mechanism 450A, 450B may be in very light contact with the one or more edges or not be in continuous contact with the one or more edges but be very close to the one or more edges, so as to restrain the carrier structure 414 should the carrier structure 414 move.

[0075] In some embodiments, the carrier structure 414 may be released from the chuck 432 by removal of the edge restraining mechanism, such as by retraction of one or more of the arms 454A, 454B. The carrier structure 414 may instead or additionally be removed by any appropriate removal method, such as by gravitational force, mechanical deformation, etc.

[0076] Although the chuck 432 (and other chuck described here) is described as holding the carrier structure 414 for radiation-mediated die bonding, the chuck 432 may be used for other applications as well or instead. For example, the transparent chucking mechanisms described herein may be used to secure structures for laser etching, backside exposure, or any other application in which a transparent holding mechanism may be desired and / or required.

[0077] Figures 5A-5C are schematic diagrams illustrating example electrostatic holding methods for securing a die carrier. Figure 5A is a cross-sectional view of bonding of a donor die (e.g., donor die 502) to a target die (e.g., target die 504). Figures 5B and 5C are plan views of exemplary electrodes in a die carrier (e.g., die carrier 514) and a chuck (e.g., chuck 532). Figure 5A-5C is described with reference to “donor die” and “target die”, which are relative descriptors as used herein and donor die may instead be target die and vice versa. A donor die may instead be a donor substrate and a target diemay instead be a target substrate and a donor die may be bonded to a target substrate, a donor substrate may be bonded to a target substrate, and a donor substrate may be bonded to a target die. Multiple donor dies may be bonded to a single target die and vice versa. Radiation-mediated release may be used with any appropriate die bonding method, such as any of those previously described. The electrostatic holding methods described in relation to Figures 5A-5C may also be combined with the edge restraining methods described in relation to Figure 4, in part or in full.

[0078] In Figure 5 A, one or more donor dies 502 are supported by a carrier structure 514. The donor die 502 may be any appropriate donor die, such donor die described in reference to any previous figure. The carrier structure 514 is substantially transparent to at least a range of radiation (e.g., electromagnetic radiation, visible light, UV radiation, a particle or electron beam, etc.). The carrier structure 514 may be any appropriate carrier structure in which attractive forces may be induced by application of an external and / or internal electric field. In some embodiments, the carrier structure 514 may be the carrier structure 414 of Figure 4. In some embodiments, the carrier structure 514 contains one or more substantially transparent electrodes 570. In some embodiments, the one or more transparent electrodes 570 comprises a substantially transparent electrode material. In some embodiments, the carrier structure 514 may contain one or more electrodes that are transparent but comprise non-transparent material, such as one or more non-transparent material electrodes which have one or more perforations or one or more other windows in which they are transparent. The carrier structure 514 may be fully transparent, partially transparent (e.g., at least 99% transparent, at least 95% transparent, at least 90% transparent, at least 80% transparent, at least 50% transparent, etc.), intermittently transparent (for example, transparent in areas on which donor die 502 are placed), etc. The one or more transparent electrodes 570 may be of any appropriate material, such as of a transparent conducting oxide (TCO), such as zinc oxide, tin oxide, indium oxide, cadmium oxide, fluorine tin oxide, and / or a combination selected therefrom. A transparent electrode 570 may be sufficiently transparent that radiation transmitted through the transparent electrode 570 is capable of initiating radiation -mediated bonding of the donor die 502 to the target die 504. A transparent electrode 570 may additionally or alternatively be formed having one or more perforations, one or more windows or other configurations such that the transparent electrode 570 does not cover the full surface area of the carrier structure 514 (as will be further described in reference to Figures 5B and 5C). The carrier structure 514 and any transparent electrode 570 may be transparent to visible light, infrared radiation, ultraviolet radiation, a particle or electron beam, etc. The carrier structure 514 may be fabricated of any appropriate material, such as glass, silicon dioxide, sapphire, acrylic, etc. The carrier structure 514 may be fabricated of a material with any appropriate atomic structure — e.g., crystalline, semi-crystalline, amorphous, plastic, etc. A transparent electrode 570 may be fabricated in the carrier structure 514 (or on the carrier structure 514) by any appropriate means, such as e-beam deposition, chemical vapor deposition, ion implantation, etc. The carrier structure 514 may be a flexible substrate, such as a flexible polymer supported by a superstructure (such as a superstructurewith one or more radiation windows). A transparent electrode 570 may be flexible (e.g., deformable) in a carrier structure 514 that is flexible. The carrier structure 514 may be a substantially inflexible substrate. The thickness of the carrier structure 514 (e.g., in the Z direction) may vary depending on which type of material the carrier structure 514 is fabricated from, such as where thickness may be selected based on deformation thresholds, electromagnetic radiation extinction coefficients, etc. A thickness of the transparent electrode 570 may vary depending on the type of material of which it is constructed, such as where thickness may be selected based on deformation thresholds, electromagnetic radiation extinction coefficients, etc.

[0079] The carrier structure 514 may have any properties or be used to perform any function previously described in reference to the carrier structure 114 (or carrier structure 116) of Figures 1A- 1D, carrier structure 214 (or carrier structure 216) of Figures 2A-2F, carrier structure 314, carrier structure 316, or carrier structure 314-2 of Figures 3A-3J), and the carrier structure 414 of Figure 4

[0080] The donor die 502 may be adhered to the carrier structure 514 by any appropriate method, such as those described herein. Where adhesive is used, in order to cause volumetric expansion of the adhesive, radiation may be supplied by a source 542 through the carrier structure 514 to the adhesive on the back side of the donor die 502. The source 542 may be any appropriate source, such as source 442 of Figure 4. The volumetric expansion of the adhesive may cause release of the donor die 502 from the carrier structure 514 and towards (e.g., in the direction 530) the target die 504 on a carrier structure 516. The radiation-mediated placement of the donor die 502 on the target die 504 may enable die bonding, as previously described.

[0081] The carrier structure 514 may be supported, e.g., held, by a chuck 532. In some embodiments, the chuck 532 may have properties or be used to perform any function previously described in reference to Figures 1A-1D, Figures 2A-2F, substrate chuck 32A, substrate chuck 320B, or bonding support structure 322 of Figures 3A-3J, and / or chuck 432 of Figure 4. In some embodiments, the chuck 532 may have properties or be used to perform any function previously described as corresponding to the support structure 322A, support structure 322B, or flipper 300 of Figures 3A-3J.

[0082] The chuck 532 may be substantially similar to the chuck 432 described in reference to Figure 4, but with a transparent electrode 560. The chuck 532 is depicted as having a body extending along the x-y plane, where a first face of the chuck body meets a first face of the carrier structure 514. The chuck 532 is also depicted as having one or more sidewalls which extend down from the body in the negative z direction. This depiction is for illustrative purposes only, and the chuck body may instead be substantially planar, have one or more recessed areas, have one or more additional structures on the backside, etc., such as those described in reference to Figure 4.

[0083] The chuck 532 and transparent electrode 560 are transparent in part to at least a range of radiation (e.g., electromagnetic radiation, visible light, UV radiation, a particle or electron beam, etc.). The chuck 532 and transparent electrode 560 may be fully transparent, partially transparent (e.g., at least 99% transparent, at least 95% transparent, at least 90% transparent, at least 80% transparent, atleast 50% transparent, etc.), intermittently transparent (for example, transparent in areas corresponding to the donor die 402), etc. The chuck 532 and transparent electrode 560 may be transparent to visible light, infrared radiation, ultraviolet radiation, a particle or electron beam, etc. A transparent electrode 560 may be formed having one or more perforations, one or more windows 540 or other configurations such that the transparent electrode 560 does not cover the full surface area of the carrier structure 514. In the embodiment depicted in Figures 5A-5C, the chuck 532 is transparent to a range of radiation in the one or more windows 540. The transparent electrode 560 may or may not have one or more windows 540. The chuck 532 may instead be transparent to the range of radiation in a single window as depicted in Figure 4. The one or more windows 540 may be made of the same or a different material than the rest of the body of the chuck 532. The one or more windows 540 may be substantially the same size as or larger than the donor die 502. In some embodiments, the one or more windows 540 may be smaller than the donor die 502, such as in a mesh or other regular or irregular array configuration. The chuck 532 may be relatively opaque to radiation other than in the one or more windows 540. The chuck may be transparent to radiation in other regions in addition to the one or more windows 540. The one or more windows 540 of the chuck 532 may be transparent to the same wavelengths of radiation as the carrier structure 514 (such as if the carrier structure 514 and the one or more windows 540 are fabricated of substantially the same material), to a set of wavelengths of radiation within the range that the carrier structure 514 is transparent to (e.g., to a subrange of wavelengths which pass through the carrier structure 514), or to wavelengths which the carrier structure 514 is not transparent to. That is, the one or more windows 540 may have an overlapping but not identical transparency range with the carrier structure 514. For example, the carrier structure 514 may be transparent to a larger range of wavelengths inclusive of the range of wavelengths to which the one or more windows 540 are transparent, or vice versa. The one or more windows 540 may extend through the body of the chuck 532 (e.g., from the top of the chuck to the bottom of the chuck, as depicted) in the direction of radiation exposure. The face of the chuck 532 to which the carrier structure 514 is held may comprise one or more windows 540.

[0084] The body of the chuck 532 and the one or more windows 540 may be constructed of the same or different materials. For example, the body of the chuck 532 may be constructed of aluminum while the one or more windows 540 may be constructed of silicon dioxide. The one or more windows 540 may simply be empty space. The body of the chuck 532 and the one or more windows 540 may be constructed of substantially the same material, but with different absorptive properties. For example, the one or more windows 540 may be fabricated of a transparent polymer, such as plexiglass, while the body of the chuck 532 may be constructed of a non-transparent (for example, dyed) version of the same polymer, such as an opaque plexiglass. The one or more windows 540 may be fabricated of any appropriate material, such as glass, silicon dioxide, sapphire, acrylic, etc. The one or more windows 540 may be fabricated of a material with any appropriate atomic structure — e.g., crystalline, semicrystalline, amorphous, plastic, etc. The one or more windows 540 may be constructed of a rigidmaterial. The one or more windows 540 may be constructed of flexible material, including a flexible material supported by a rigid superstructure (such as a wire or mesh superstructure with is at least partially transparent to radiation). The one or more windows 540 may be substantially inflexible. The thickness of the one or more windows 540 (e.g., in the Z direction) may vary depending on which type of material the one or more windows 540 are fabricated from, such as where thickness may be selected based on rigidity, deformation thresholds, electromagnetic radiation extinction coefficients, etc. The body of the chuck 532 may be fabricated of any appropriate material, such as metal, plastic (e.g., hard plastic), glass, silicon dioxide, sapphire, polymer, etc. The body of the chuck 532 may be constructed of a rigid material. The body of the chuck 532 may be additively or subtractively formed by any appropriate machining process, such as milling, casting, 3D printing, etc. The body of the chuck 532 may be fabricated and an opening formed for the one or more windows 540. The one or more windows 540 may be held into the body of the chuck 532 by any appropriate fastening mechanism, such as glue, clamps, etc. In some embodiments, the transparent electrode 560 may extend into the one or more windows 540. In some embodiments, the transparent electrode may not extend into the one or more windows 540, and may be substantially contained within the body of the chuck 532. In some embodiments, the one or more windows 540 may make up substantially all of the chuck 532. For example, the chuck 532 may be substantially transparent or fabricated of a mesh or other pierced material.

[0085] In order to bond the donor die 502 to target die 502, radiation may be supplied through the carrier structure 514 by the source 542. The radiation from the source 542 may penetrate through the chuck 532 (e.g., through the one or more window 540 of the chuck 532) to reach the carrier structure 514 and through the carrier structure 514 to reach the adhesive on the backside of the donor die 502. The radiation may also be transmitted through one or more transparent electrodes, such as the transparent electrode 570 and the transparent electrode 560. In some embodiments, there may be relative movement, such as in direction 544, between the radiation and the adhesive of the donor die 502 in order to release the donor die 502 for die bonding. For example, source 542 may sweep the radiation across, such as in direction 544, the carrier structure 514. In an embodiment, the source 542 itself may move in direction 544. In an embodiment, the source 542 comprises optics (not depicted) to cause the relative movement. In an embodiment, the relative movement can be created in part by movement of the carrier structure 514.

[0086] In order to hold the carrier structure 514 against the chuck 532 (for example, for optical transmission reasons as previously described), an electrostatic clamping mechanism may be used. In some embodiments, to provide electrostatic clamping, the transparent electrode 560 of the chuck 532 may be energized, such as by application of a direct or alternating current or voltage (for example, applied by voltage source 562). The transparent electrode 560 may also be connected to a ground 564. In some embodiments, the transparent electrode 560 may induce an opposite and attractive charge in the carrier structure 514 (which may or may not contain a transparent electrode), leading toelectrostatic clamping of the carrier structure 514 to the chuck 532. In some embodiments, the transparent electrode may induce an opposite and attractive charge in a transparent electrode 570 of the carrier structure 514, leading to electrostatic clamping of the carrier structure 514 to the chuck 532. In some embodiments, a transparent electrode 570 of the carrier structure 514 may also or instead be directly energized, such as by connection to a voltage source 572 and ground 574. The charge and / or voltage applied to the transparent electrode 570 may be opposite to the charge applied to the transparent electrode 560, leading to electrostatic clamping of the carrier structure 514 to the chuck 532.

[0087] The chuck 532 is depicted as holding the carrier structure 514 up (e.g., opposite the direction of gravity), but may instead or additionally hold the carrier structure in any appropriate direction, as previously described in relation to Figure 4.

[0088] The carrier structure 514 may be released from the chuck 532 by reverse biasing of the transparent electrode 560 and / or the transparent electrode 570. In some embodiments, the carrier structure 514 may be released from the chuck by removal (such as grounding) of the charge or voltage from the transparent electrode 560 and / or the transparent electrode 570. The carrier structure 514 may instead or additionally be removed by any appropriate removal method, such as by gravitational force, mechanical deformation, etc.

[0089] An electrostatic clamping mechanism may be used in addition to any other clamping method, such as the mechanical clamping method described in relation to Figure 4.

[0090] Figures 5B and 5C are plan views of example configurations of the transparent electrode 560 and the transparent electrode 570 in the carrier structure 514 and the chuck 532. In Figures 5B and 5C, the transparent electrode 570 is depicted as occurring in the carrier structure 514 in areas other than areas in which the donor die 502 are placed. In some embodiments, the transparent electrode 570 may be configured (e.g., patterned) to provide apertures (e.g., windows) in the carrier structure 514 on which the donor dies 502 may be placed such that the transparent electrode 570 does not interpose between any radiation source and any volumetrically expandable adhesive on the back side of the donor dies 502. In some embodiments, the transparent electrode 570 may instead be substantially unpattemed or otherwise interpose between at least some of the donor die 502 and a radiation source (such as source 542).

[0091] In Figure 5B, the transparent electrode 570 is depicted as a grid or mesh occurring outside of regions where the donor die 502 are placed. In Figure 5C, the transparent electrode 570 is depicted as a ring electrode occurring outside of the region where the donor die 502 are placed. These illustrations are provided as examples only, and the transparent electrode 570 may have any appropriate configuration.

[0092] In Figures 5B and 5C, the transparent electrode 560 is depicted as occurring in the chuck 532 in regions corresponding to regions of the carrier structure 514 in which the donor die 502 are placed. In some embodiments, the transparent electrode 560 may be configured (e.g., patterned) to provideapertures (e.g., windows) in the chuck 532 corresponding to regions in the carrier structure 514 on which the donor dies 502 may be placed such that the transparent electrode 560 does not interpose between any radiation source and any volumetrically expandable adhesive on the back side of the donor dies 502. In some embodiments, the transparent electrode 560 may instead be substantially unpattemed or otherwise interpose between at least some of the donor die 502 and a radiation source (such as source 542). In some embodiments, transparent electrode 560 may be configured to correspond to a pattern of the transparent electrode 570 — e.g., such that the locations of the transparent electrode 560 and the transparent electrode 570 are reflections of one another about the x- y plane.

[0093] In Figure 5B, the transparent electrode 570 is depicted as a grid or mesh occurring outside of regions corresponding to the areas of the carrier structure 514 where the donor die 502 are placed. In Figure 5C, the transparent electrode 570 is depicted as a ring electrode occurring outside of the region corresponding to the areas of the carrier structure 514 where the donor die 502 are placed. These illustrations are provided as examples only, and the transparent electrode 570 may have any appropriate configuration.

[0094] Figures 6A-6G are schematic diagrams illustrating an example fluid-based surface tension method of securing a die carrier. Figure 6A-6G are cross-sectional views of bonding of a donor die (e.g., donor die 602) to a target die (e.g., target die 604). Figure 6A-6G is described with reference to “donor die” and “target die”, which are relative descriptors as used herein and donor die may instead be target die and vice versa. A donor die may instead be a donor substrate and a target die may instead be a target substrate and a donor die may be bonded to a target substrate, a donor substrate may be bonded to a target substrate, and a donor substrate may be bonded to a target die. Multiple donor dies may be bonded to a single target die and vice versa. Radiation-mediated release may be used with any appropriate die bonding method, such as any of those previously described. In some embodiments, multiple steps which are depicted as occurring substantially simultaneously in Figures 6A-6G may be performed sequentially. In some embodiments, multiple steps which are depicted as occurring sequentially in Figures 6A-6G may be performed substantially simultaneously. In some embodiments, multiple donor dies may be aligned or placed on their respective target dies substantially simultaneously, including donor dies which are proximate (including adjacent) or distant (e.g., nonadj acent but within the same target substrate). In some embodiments, steps may be performed in a different order. The surface tension holding methods described in relation to Figures 6A-6F may be combined with the edge holding methods described in relation to Figure 4, in part or in full, and / or with the electrostatic holding methods described in relation to Figures 5A-5C, in part or in full.

[0095] In Figure 6A, a donor die 602 is supported by a carrier structure 614. The donor die 602 may be any appropriate donor die, such donor die described in reference to any previous figure. The carrier structure 614 is transparent to at least a range of radiation (e.g., electromagnetic radiation, visible light, UV radiation, a particle or electron beam, etc.). In some embodiments, the carrier structure 614may be or have properties described in relation to the carrier structure 414 of Figure 4. In some embodiments, the carrier structure 614 may be or have properties described in relation to the carrier structure 514 of Figures 5A-5C. The carrier structure 614 may be fully transparent, partially transparent (e.g., at least 99% transparent, at least 95% transparent, at least 90% transparent, at least 80% transparent, at least 50% transparent, etc.), intermittently transparent (for example, transparent in areas on which donor die 502 are placed), etc. The carrier structure 614 may be fabricated of any appropriate material and may or may not contain one or more electrodes, one or more edge attachment points, etc. The carrier structure 614 may be flexible or rigid, as previously described.

[0096] The carrier structure 614 may have any properties or be used to perform any function previously described in reference to the carrier structure 114 (or carrier structure 116) of Figures 1A- 1D, carrier structure 214 (or carrier structure 216) of Figures 2A-2F, carrier structure 314, carrier structure 316, or carrier structure 314-2 of Figures 3A-3J, the carrier structure 414 of Figure 4, and / or the carrier structure 514 of Figures 5A-5C.

[0097] The donor die 602 may be adhered to the carrier structure 614 by any appropriate method, such as by those described in relation to Figure 4. Where adhesive is used, in order to cause volumetric expansion of the adhesive, radiation may be supplied by a radiation source 642 through the carrier structure 614 to the adhesive on the back side of the donor die 604. The source 642 may be any appropriate radiation source, such as source 442 of Figure 4.

[0098] The carrier structure 614 may be supported, e.g., held, by a chuck 632. In some embodiments, the chuck 632 may have properties or be used to perform any function previously described in reference to Figures 1A-1D, Figures 2A-2F, substrate chuck 32A, substrate chuck 320B, or bonding support structure 322 of Figures 3A-3J, chuck 432 of Figure 4, and / or chuck 532 of Figures 5A-5C. In some embodiments, the chuck 632 may have properties or be used to perform any function previously described as corresponding to the support structure 322A, support structure 322B, or flipper 300 of Figures 3A-3J.

[0099] The chuck 632 is depicted as having a body extending along the x-y plane, where a first face of the chuck body meets a first face of the carrier structure 614. The chuck 632 is also depicted as having one or more sidewalls which extend down from the body in the negative z direction. This depiction is for illustrative purposes only, and the chuck body may instead be substantially planar, have one or more recessed areas, have one or more additional structures on the backside, etc., such as those described in reference to Figure 4. The chuck 632 is depicted as holding the carrier structure 614 up (e.g., opposite the direction of gravity), but may instead or additionally hold the carrier structure in any appropriate direction, as previously described in relation to Figure 4.

[0100] In the embodiment depicted in Figures 6A-6F, the chuck 632 is transparent to a range of radiation in window 640, which is substantially equal to a first plane of the chuck which accepts the carrier structure 614. The chuck 632 is also depicted as containing a pressure transfer port 686. In some embodiments, the pressure transfer port 686 may be omitted. The pressure transfer port 686 isdepicted as centrally located in the window 640, but may be located in any appropriate location. In some embodiments, multiple pressure transfer ports may be used. In some embodiments, the pressure transfer port 686 may be located in a region of the chuck 632 which does not correspond to an area of the carrier structure 614 which supports a donor die 602. The pressure transfer port 686 may have any appropriate cross-sectional area, such as including a flow restrictor, one way valve, etc.

[0101] In Figure 6A, delivery of a fluid for the fluid-based surface tension method of securing a die carrier is depicted. A fluid 682 is delivered by, e.g., a dropper 680. In some embodiments, the dropper 680 may instead be a mister, or any other appropriate fluid delivery system that delivers fluid 682 in fluid, droplet, mist, vapor, gaseous, etc. form. The fluid 682 may be water or a water-based fluid. In some embodiments, the fluid may be an organic fluid. In some embodiments, the fluid may be an inorganic fluid. The fluid 682 may contain multiple components, such as alcohol, water, dissolved minerals, etc. The fluid 682 may be electrically conductive or insulative. The fluid 682 may be a fluid which is liquid at STP. The fluid 682 may be a fluid which is gaseous at or near STP. The fluid 682 may be delivered to the carrier structure 614 before the carrier structure 614 is brought near the chuck 632. The fluid 682 may be delivered to the carrier structure 614 while the carrier structure 614 is in proximity with the chuck 632. In some embodiments, the fluid 684 may be delivered between the carrier structure 614 and the plane of the chuck 632 to which it is to be held, including by delivery of the fluid 682 from or through the chuck 632. In some embodiments, the fluid 684 may be delivered additionally or instead to the plane of the chuck 632 to which the carrier structure 614 is held. The fluid 682 may create a fluid layer 684 on a face of the carrier structure 614. The fluid layer 684 may have a thickness determined by the amount of fluid 682 delivered, the surface tension between the fluid 682 and the plane of the carrier structure 614, and the spreading coefficient of the fluid 682.

[0102] In Figure 6B, there is relative movement between the carrier structure 614 and the chuck 632, such as movement of carrier structure 614 in direction 688, such that the fluid layer 684 is sandwiched between the carrier structure 614 and the chuck 632.

[0103] In Figure 6C, the carrier structure 614 comes to near contact with the plane of the chuck 632. The fluid layer 684 is sandwiched between the carrier structure 614 and the plane of the chuck 632. Surface tension between the fluid of the fluid layer 684, the carrier structure 614, and the plane of the chuck 632 provides an attractive force which holds the carrier structure 614 to the plane of the chuck 632. The strength of the attractive force may be determined by the strength of the surface tension between the fluid of the fluid layer 684 and the carrier structure 614 surface and the surface of the plane of the chuck 632. The strength of the attractive force may also be determined by the thickness of the fluid of the fluid layer 684, coverage of the fluid layer 684, etc. In some embodiments, the attractive force associated with surface tension may be focused on a center of the carrier structure 614, but may be located at another region. In embodiment, another mechanism may be used to provide securing force to the carrier structure 614 in another region (for example, an edge restraining mechanism may be used). In some embodiments, when the carrier structure 614 and the plane of thechuck 632 come into near contact, excess fluid from the fluid layer 684 may be squeezed out from between the carrier structure 614 and the chuck 632, including through the pressure transfer port 686.

[0104] In Figure 6D, the carrier structure 614 is held to the plane of the chuck 632 by the fluid-based surface tension method.

[0105] In Figure 6E, in order to cause volumetric expansion of the adhesive, radiation may be supplied by a radiation source 642 through the carrier structure 614 to adhesive on the back side of the donor die 602. The source 642 may be any appropriate radiation source, such as source 442 of Figure 4. The volumetric expansion of the adhesive may cause release of the donor die 602 from the carrier structure 614 and towards (e.g., in the direction 630) the target die 604 on a carrier structure 616. The radiation-mediated placement of the donor die 602 on the target die 604 may enable die bonding, as previously described. In some embodiments, there may be relative movement, such as in direction 644, between the radiation and the adhesive of the donor die 602 in order to release the donor die 602 for die bonding. For example, source 642 may sweep the radiation across, such as in direction 644, the carrier structure 614. In an embodiment, the source 642 itself may move in direction 644. In an embodiment, the source 642 comprises optics (not depicted) to cause the relative movement. In an embodiment, the relative movement can be created in part by movement of the carrier structure 614.

[0106] In Figure 6F, the carrier structure 614 may be released from the chuck 632 in various way. For example, there may be delivery of a pressure to disengage the fluid-based surface tension holding mechanism. The pressure may be delivered by mechanical deformation, such as by a movement of a detent or other element which causes deformation of a surface of the chuck 632 and / or the carrier structure 614 (such as by allowing gas (e.g., air) into the region between the chuck 632 and the carrier structure 614). In an embodiment, as depicted in Figure 6F, a fluid 690 may be delivered, e.g., in direction 692, such as through the pressure transfer port 686, to evaporate, remove, or otherwise displace the fluid layer 684. The fluid 690 may be a gas. The fluid 690 may be particulate free air, nitrogen, etc. The fluid 690 may have substantially no or low levels of vapor corresponding to the fluid of the fluid layer 684. The fluid 690 may dry (e.g., cause evaporation of) the fluid of the fluid layer 684. In some embodiments, the fluid 690 may be supplied in sufficient pressure to provide deformation (e.g., deformation 694) of the carrier structure 614 and / or the chuck 632 to deform the carrier structure 614 and / or the chuck 632 in order to break the fluid-based surface tension seal between those two elements. In some embodiments, the fluid-based surface tension may be broken by heat transfer, e.g., by heating to, e.g., evaporate the fluid and / or by cooling. In some embodiments, the fluid-based surface tension may be broken by removal of another holding mechanism. For example, if an edge restraining mechanism is used, removal of contact with the carrier structure 614 or engagement of contact of the edge restraining mechanism may cause the fluid-based surface tension to be broken by gravitational force. In another example, if an electrostatic clamping mechanism is used, reverse biasing of the electrostatic clamping mechanism may cause the fluid-based surface tension to be broken, with or without accounting for effects of gravitational force. The carrier structure 614 mayinstead or additionally be removed by any appropriate removal method, such as by gravitational force alone, evaporation of the fluid of the fluid layer 684 without the use of the fluid 690, etc.

[0107] In Figure 6G, the carrier structure 614 may separate from the chuck 632 (e.g., along direction 696). In some embodiments, the carrier structure 614 may be reused for additional die bonding, such as by attachment of one or more additional donor die 602 and subsequent re-securement to the chuck 632 or another appropriate chuck.

[0108] In an embodiment, radiation-mediated release is used with any appropriate die bonding or holding method, such as any of those previously described.

[0109] Figure 7 is a flowchart which illustrates an exemplary method of die placement. Each of these operations is described in detail below. The operations of method 700 presented below are intended to be illustrative. In some embodiments, method 700 may be accomplished with one or more additional operations not described, and / or without one or more of the operations discussed. Additionally, the order in which the operations of method 700 are illustrated in Figure 7 and described below is not intended to be limiting. In some embodiments, one or more portions of method 700 may be implemented (e.g., by simulation, modeling, etc.) in one or more processing devices (e.g., one or more processors). The one or more processing devices may include one or more devices executing some or all of the operations of method 700 in response to instructions stored electronically on an electronic storage medium. The one or more processing devices may include one or more devices configured through hardware, firmware, and / or software to be specifically designed for execution of one or more of the operations of method 700, for example.

[0110] At an operation 710, a plurality of donor die locations are obtained. The donor die locations may be obtained via measurement of one or more positions of the donor dies along one or more dimensions. The donor dies may lie on or be part of a donor substrate (e.g., a carrier structure, a semiconductor substrate, etc.), and the locations of the plurality of donor dies may be obtained with respect to that donor substrate. The locations of the plurality of donor die may be measured with respect to a measurement mark. The locations of the plurality of donor dies may be measured in-plane (e.g., in the x-y plane). The locations of the plurality of donor dies may also be measured via a first method in-plane and measured out of plane (e.g., in the Z direction) via a second method. For example, the locations of the plurality of donor dies may be measured based on one or more images in-plane. The locations of the plurality of donor dies may be obtained from a two-dimensional image, which may show locations of an edges or comer of a donor die with respect to positions on a support structure or on a die actuator. The locations of the plurality of donor dies may be obtained based on one or more features (for example, one or more electrically active areas) on an exposed surface of the donor die. These one or more features of the donor die may be used as an alignment mark or reference mark. In some embodiments, alignment marks may be included as exposed features of the donor die. The alignment marks may be specifically added for die bonding or may be alignment marks corresponding to previous fabrication steps. The plurality of donor die locations may be measured orobtained from storage.

[0111] At an operation 720, a plurality of target die locations are obtained. The target dies may lie on or be part of a target substrate (e.g., a carrier structure, a semiconductor substrate, etc.), and the locations of the plurality of target dies may be obtained with respect to that target substrate. The locations of the plurality of target die may be obtained in any appropriate method, including any of those described in reference to the operation 710.

[0112] At an operation 730, a donor die is selected from the plurality of donor dies. The donor die may be selected based on position (e.g., along a row, along a column), displacement (e.g., donor die closest to an ideal position), thickness (e.g., thicker dies may be placed before thinner dies, including if donor dies include two or more types of dies), etc. The donor die may have a corresponding target die, such as a target die in a corresponding location on a target substrate (e.g., target die carrier structure). In some embodiments, a target die may be selected, by any appropriate method, and a donor die selected based on its correspondence to the selected target die. The donor die and the target die may be brought together such that donor die and its corresponding target die are separated by a distance which may be traversed by the die placement method. The donor die and target die may be grossly aligned (e.g., coarse aligned), such as to within a threshold of coarse alignment. The donor die and target die may be held in proximity by one or more substrates, chucks, actuators, adhesives, etc.

[0113] At an operation 740, the relative position between the selected donor die and the corresponding target die is adjusted to have alignment between the donor die and the corresponding target die. Adjusted includes cases in which locations are minimally or substantially not adjusted (e.g., after measurement or bringing into proximity), such as if a measured location corresponds to the target location within a threshold. In an embodiment, the position of the donor die may be adjusted by action of a die actuator, a substrate holder, a chuck, etc. The position of the donor die may be adjusted by action of a substrate handling apparatus. The position of the donor die may be adjusted in one or more directions, such as in the X-Y plane. Alternatively or additionally to adjustment of the location of the donor die, the position of the target die may be adjusted, by any appropriate method, such as any of those previously described. Adjustment of the relative position between the donor and target die may include iterative measurement of donor and / or target die location, including as adjustment occurs.

[0114] Adjustment of the location of the donor die may occur based on an alignment location for the donor die. The alignment location may be a target (e.g., target location) for placement of the donor die. A target (e.g., target location) may be obtained, such as at operation 720, from measurement of the target die position. The target may correspond to a location of the target die. The target may correspond to a plurality of locations on the target die. The target may be a position (e.g., a position in three dimensions such as along X, Y, and Z axes, positions in six directions such as along X, Y, and Z axes and with respect to angles of rotation about those axes, etc.). The target may be a set of positions, for example two or more positions of or on a target die to which areas of the donor die are to bebonded. Additionally or alternatively, adjustment of the location of the target die may occur based on an alignment location for the target die. The alignment location may be a target (e.g., target location) for placement of the donor die. A target (e.g., target location) may be obtained, such as at operation 710, from measurement of the donor die position. The target may correspond to a location of the donor die. The target may correspond to a plurality of locations on the donor die.

[0115] At an operation 750, the selected donor die is placed on the corresponding target die. The donor die may be placed on the target die by any appropriate method, such as by movement of a die actuator, by radiation-mediated bonding, by stamping, by electrostatic attraction, etc. The donor die may experience alignment, including self-alignment, as the donor die is brought into contact with the target die. The donor die may be adhered to the target die as it contacts the target die, such as by van der Waals forces. In some embodiments, an additional donor die may be placed on the same or different target die.

[0116] At an operation 760, it is determined if additional donor die remain for placement. If additional donor die (e.g., on the donor substrate or substrate) remain for placement, the flow continues to the operation 730 where another donor die is selected. If no additional donor die remain for placement, flow continues to operation 770, where the bonding of the plurality of dies is completed.

[0117] In an embodiment, a particular donor die and target die are bonded at the time the donor die is placed on the target die, e.g., through intermolecular bonding. In an embodiment, the donor die is bonded, such as through annealing or other bonding process, to the target die after placement of the donor die on the target die. In an embodiment, a bonding of a donor and target die is completed before a next donor die is placed on a target die. In an embodiment, bonding of a donor and target die is completed after a plurality of donor dies are placed on respective target dies, e.g., after all the donor dies on a donor substrate are placed. In an embodiment, a donor die placed on a target die is annealed to form or enhance electrical connection. In an embodiment, the annealing of a particular donor die and target die can be done prior to a next donor die is placed on a target die. In an embodiment, annealing of a donor and target die is completed after a plurality of donor dies are placed on respective target dies, e.g., after all the donor dies on a donor substrate are placed. The donor die may be held against the target die for a bonding or annealing time period. A donor die and target die pair may be released from a substrate or other holding apparatus before annealing or after annealing has occurred.

[0118] As described above, method 700 (and / or the other methods and systems described herein) is configured for die placement.

[0119] Figure 8 is a flowchart which illustrates an exemplary method for die bonding with a securable die carrier. Each of these operations is described in detail below. The operations of method 800 presented below are intended to be illustrative. In some embodiments, method 800 may be accomplished with one or more additional operations not described, and / or without one or more of theoperations discussed. Additionally, the order in which the operations of method 800 are illustrated in Figure 8 and described below is not intended to be limiting. In some embodiments, one or more portions of method 800 may be implemented (e.g., by simulation, modeling, etc.) in one or more processing devices (e.g., one or more processors). The one or more processing devices may include one or more devices executing some or all of the operations of method 800 in response to instructions stored electronically on an electronic storage medium. The one or more processing devices may include one or more devices configured through hardware, firmware, and / or software to be specifically designed for execution of one or more of the operations of method 800, for example.

[0120] At an operation 810, a carrier structure having a die is placed near a securing face of a chuck. The carrier structure may contain a die held (e.g., adhered) by any appropriate method, such as those previously described. The carrier structure may be a transparent carrier structure. The carrier structure may be a wafer having undiced die therein. The carrier structure may have a face which is shaped in a manner corresponding to the securing face of the chuck, such that the securing face of the chuck and the face of the carrier structure may be held in contact. Placing the carrier structure near the securing face of the chuck may include in contact, in proximity but not in contact, gradual relative movement between the carrier structure and the chuck so that the carrier structure can be become in contact, or in proximity but not in contact, with the chuck, etc. The chuck may be any appropriate chuck, such as those previously described.

[0121] At an operation 820, a holding mechanism may be activated. The holding mechanism may be one or more selected from: an edge restraining mechanism, an electrostatic holding mechanism, a bonding mechanism, and / or a fluid-based surface tension holding mechanism. Activation of the holding mechanism may include one or more selected from: movement or extension of one of more edge restraining structures, energizing of one or more electrodes, establishment of bonding conditions, delivery of fluid between the carrier structure and the chuck, etc. Activation of the holding mechanism may include bringing the carrier structure into physical contact, or into close proximity, with the chuck. Activation of the holding mechanism may include measurement of an alignment between the carrier structure (or a die of the carrier structure) with the chuck. In some embodiments, if the alignment between the carrier structure and the chuck is determined to be deficient after the activation of the holding mechanism, the holding mechanism may be released. In some embodiments, the holding mechanism may be re-applied until the alignment meets a minimum alignment threshold or any other appropriate termination criterion.

[0122] At an operation 830, one or more dies of the carrier structure is aligned with a target. The one or more dies may be aligned with a target die based on measurements of the location of the one or more dies (such as with respect to a carrier structure, the chuck, etc.) and / or the location of the target . The one or more dies and the target may be aligned by any appropriate method, including any of those previously discussed. The one or more dies may be aligned by movement of the chuck, which may in turn move the carrier structure it holds and the dies thereon.

[0123] At an operation 840, one or more dies of the carrier structure is bonded with a target, such as a target die. In an embodiment, radiation is supplied through the carrier structure to an adhesive on the one or more dies aligned to the target and for bonding. The radiation may be shaped to pinpoint one die at a time. The radiation spot size may be substantially smaller than the size of the die. The radiation may be directed at a central portion of the die, at an edge or comer of the die, etc. The radiation may be moved across the die. The radiation may function to cause the adhesive to decompose into at least a gaseous portion or otherwise volumetrically expand. The radiation may function to change the adhesive from a solid or liquid to a gas. The radiation may function to thermally expand the adhesive. The radiation may change the volume of the adhesive, in a region of the adhesive smaller in area than the target die, by any appropriate manner. In some embodiments, the radiation may change the volume of the adhesive in an area which may be the same size as or larger than the die, such as if the volumetric expansion does not accompany a gaseous phase. The radiation may be delivered until the one or more aligned dies are detached from the carrier structure. If one or more dies remain to be aligned and / or bonded, the flow may continue to the operation 830 where additional die may be aligned.

[0124] At an operation 850, the carrier structure may be released from the chuck. The carrier structure may be released by active means, such as one or more selected from: physical detent release, removal of an edge restraining mechanism, pushing by a mechanism, mechanical deformation, electrostatic repulsion, application of pressure in the form of a fluid, heat transfer to a fluid of a fluidbased surface tension mechanism, evaporation of a fluid of a fluid-based surface tension mechanism by a second supplied fluid, etc. The structure may be released by passive means, such as one or more selected from: gravitational forces, removal of active electrostatic clamping without reverse biasing, evaporation of the fluid of a fluid-based surface tension mechanism to atmosphere, etc. The carrier structure may then be re-used in another die bonding operation by application of additional die.

[0125] As described above, method 800 (and / or the other methods and systems described herein) may be configured for radiation mediated die release.

[0126] The description herein has focused on embodiments of holding / restraining of carrier structure 114, 214, 314, 414, 514, 614. The holding / restraining apparatus and / or techniques described herein can be applied mutatis mutandis to any another structure, including, for example and without limitation, structure 116, 216, 316, 416, 516, 616.

[0127] In an embodiment, the techniques and apparatus herein can be applied to die to die bonding, substrate to substrate bonding, die to substrate bonding, etc. For example, the techniques and apparatus herein can be applied to bonding an individual donor die to an individual target die. In an embodiment, the techniques and apparatus herein can be applied to bonding a group of donor dies to one or more target dies at a substantially same time or a group of target dies to one or more donor dies at a substantially same time. In an embodiment, the techniques and apparatus herein can be applied to bonding one or more donor dies to a substrate comprising one or more target dies formed therein orthereon or bonding one or more target dies to a substrate comprising one or more donor dies formed therein or thereon. In an embodiment, the techniques and apparatus herein can be applied to bonding a full or partial substrate comprising donor dies to one or more target dies or bonding a full or partial substrate comprising target dies to one or more donor dies. Thus, the techniques and apparatus herein can be applied to practically every form of die bonding, whether bonding dies individually, bonding dies in a group, bonding dies as part of a full or partial substrate, etc.

[0128] Figure 9 is a diagram of an example computer system CS that may be used to implement one or more of the operations described herein. Computer system CS includes a bus BS or other communication mechanism for communicating information, and a processor PRO (or multiple processors) coupled with bus BS for processing information. Computer system CS also includes a main memory MM, such as a random-access memory (RAM) or other dynamic storage device, coupled to bus BS for storing information and instructions to be executed by processor PRO. Main memory MM also may be used for storing temporary variables or other intermediate information during execution of instructions by processor PRO. Computer system CS further includes a read only memory (ROM) ROM or other static storage device coupled to bus BS for storing static information and instructions for processor PRO. A storage device SD, such as a magnetic disk or optical disk, is provided and coupled to bus BS for storing information and instructions.

[0129] Computer system CS may be coupled via bus BS to a display DS, such as a cathode ray tube (CRT) or flat panel or touch panel display for displaying information to a computer user. An input device ID, including alphanumeric and other keys, is coupled to bus BS for communicating information and command selections to processor PRO. Another type of user input device is cursor control CC, such as a mouse, a trackball, or cursor direction keys for communicating direction information and command selections to processor PRO and for controlling cursor movement on display DS. This input device typically has two degrees of freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y), that allows the device to specify positions in a plane. A touch panel (screen) display may also be used as an input device.

[0130] In some embodiments, portions of one or more methods described herein may be performed by computer system CS in response to processor PRO executing one or more sequences of one or more instructions contained in main memory MM. Such instructions may be read into main memory MM from another computer-readable medium, such as storage device SD. Execution of the sequences of instructions included in main memory MM causes processor PRO to perform one or more process steps (operations) described herein. One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in main memory MM. In some embodiments, hard-wired circuitry may be used in place of or in combination with software instructions. Thus, the description herein is not limited to any specific combination of hardware circuitry and software.

[0131] The term “computer-readable medium” and / or “machine readable medium” as used hereinrefers to any medium that participates in providing instructions to processor PRO for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical or magnetic disks, such as storage device SD. Volatile media include dynamic memory, such as main memory MM. Transmission media include coaxial cables, copper wire and fiber optics, including the wires that comprise bus BS. Transmission media can also take the form of acoustic or radiation waves, such as those generated during radio frequency (RF) and infrared (IR) data communications. Computer- readable media can be non-transitory, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH- EPROM, any other memory chip or cartridge. Non-transitory computer readable media can have instructions recorded thereon. The instructions, when executed by a computer, can implement any of the operations described herein. Transitory computer-readable media can include a carrier wave or other propagating electromagnetic signal, for example.

[0132] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to processor PRO for execution. For example, the instructions may initially be borne on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to computer system CS can receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector coupled to bus BS can receive the data carried in the infrared signal and place the data on bus BS. Bus BS carries the data to main memory MM, from which processor PRO retrieves and executes the instructions. The instructions received by main memory MM may optionally be stored on storage device SD either before or after execution by processor PRO.

[0133] Computer system CS may also include a communication interface CI coupled to bus BS. Communication interface CI provides a two-way data communication coupling to a network link NDL that is connected to a local network LAN. For example, communication interface CI may be an integrated services digital network (ISDN) card or a modem to provide a data communication connection to a corresponding type of telephone line. As another example, communication interface CI may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, communication interface CI sends and receives electrical, electromagnetic, or optical signals that carry digital data streams representing various types of information.

[0134] Network link NDL typically provides data communication through one or more networks to other data devices. For example, network link NDL may provide a connection through local network LAN to a host computer HC. This can include data communication services provided through the worldwide packet data communication network, now commonly referred to as the “Internet” INT.Local network LAN (Internet) may use electrical, electromagnetic, or optical signals that carry digital data streams. The signals through the various networks and the signals on network data link NDL and through communication interface CI, which carry the digital data to and from computer system CS, are exemplary forms of carrier waves transporting the information.

[0135] Computer system CS can send messages and receive data, including program code, through the network(s), network data link NDL, and communication interface CL In the Internet example, host computer HC might transmit a requested code for an application program through Internet INT, network data link NDL, local network LAN, and communication interface CL One such downloaded application may provide all or part of a method described herein, for example. The received code may be executed by processor PRO as it is received, and / or stored in storage device SD, or other nonvolatile storage for later execution. In this manner, computer system CS may obtain application code in the form of a carrier wave.

[0136] Embodiments include the following numbered clauses:Clause 1 : A chuck configured to hold a carrier with one or more donor dies, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier.Clause 2: The chuck of clause 1, wherein the chuck is substantially transparent to the radiation in one or more regions corresponding to one or more areas of the carrier, the one or more areas configured for donor die placement.Clause 3: The chuck of clause 2, wherein the carrier is substantially transparent to the radiation in the one or more areas.Clause 4: The chuck of clause 2 or clause 3, wherein the chuck is substantially transparent to the radiation in a region corresponding to substantially all of the one or more areas of the carrier.Clause 5: The chuck of any preceding clause, wherein a mechanism configured to hold the carrier to the chuck is substantially transparent to the radiation.Clause 6: The chuck of any preceding clause, further comprising an edge restraining mechanism configured to restrain the carrier at the chuck by one or more edges of the carrier. Clause 7: The chuck of any preceding clause, further comprising a surface tension holding mechanism configured to hold a face of the carrier to a face of the chuck.Clause 8: The chuck of clause 7, wherein the surface tension holding mechanism comprises a fluid-based surface tension holding mechanism.Clause 9: The chuck of clause 7 or clause 8, further comprising a fluid delivery system configured to deliver a fluid between the face of the carrier and the face of the chuck.Clause 10: The chuck of any of clauses 7 to 9, further comprising a surface tension release mechanism.Clause 11 : The chuck of clause 10, wherein the surface tension release mechanism comprises one or more selected from: a surface deformation mechanism, a gravitational release mechanism, a pneumatic release mechanism, and / or a fluid phase change release mechanism. Clause 12: The chuck of any of clauses 8 to 11, further comprising a fluid removal system configured to remove a fluid between the face of the carrier and the face of the chuck. Clause 13: The chuck of clause 12, wherein the fluid is removed after surface tension is released.Clause 14: The chuck of clause 12 or clause 13, wherein the fluid removal system is configured to provide a vacuum and / or gas flow to remove fluid remaining on the face of the carrier and / or the face of the chuck.Clause 15: The chuck of any of clauses 8 to 14, wherein the fluid is substantially comprised of water.Clause 16: The chuck of any of preceding clause, wherein the mechanism comprises an electrostatic clamping mechanism.Clause 17: The chuck of clause 16, wherein the carrier comprises a first electrode, the first electrode being substantially transparent in the one or more areas configured for donor die placement.Clause 18: The chuck of clause 16 or clause 17, wherein the chuck comprises a second electrode, the second electrode being substantially transparent in one or more regions of the chuck corresponding to one or more areas of the carrier.Clause 19: The chuck of clause 17 or clause 18, wherein the first electrode and / or the second electrode comprises a substantially transparent material.Clause 20: The chuck of clause 19, wherein the transparent electrode is constructed at least partially of transparent conductive oxide.Clause 21 : The chuck of clause 20, wherein the transparent conductive oxide comprises one or more selected from: zinc oxide, tin oxide, indium oxide, cadmium oxide, and / or fluorine tin oxide.Clause 22: The chuck of clause 19, wherein the transparent electrode is constructed at least partially of a transparent conductive polymer.Clause 23 : The chuck of any preceding clause, configured to hold the carrier with the one or more donor dies facing away from the chuck.Clause 24: The chuck of any preceding clause, configured to hold the carrier against gravity.Clause 25: The chuck of any preceding clause, configured to hold the carrier with one or more donor dies for die bonding.Clause 26: The chuck of any preceding clause, configured to hold the carrier for light induced forward transfer die bonding of one or more donor dies.Clause 27: A system for positioning donor dies at acceptor locations comprising the chuck of any of the preceding clauses.Clause 28: A system comprising: the chuck of any of clauses 1 to 26; and a positioning system configured to position the chuck and one or more donor dies held thereon relative to one or more acceptor locations.Clause 29: The system of clause 28, further comprising a radiation emission system configured to release the one or more donor dies from the carrier towards the one or more acceptor locations.Clause 30: A system for die bonding comprising the chuck of any of clauses 1 to 26.Clause 31 : A method comprising: positioning a carrier supporting one or more donor dies near a face of a chuck, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier; activating a holding mechanism configured to hold the carrier to the face of the chuck; and controlling a relative position of the chuck and an acceptor location such that at least one donor die of the one or more donor dies aligns with the acceptor location for die bonding.Clause 32: The method of clause 31, further comprising causing release of the at least one donor die towards the acceptor location.Clause 33: The method of clause 31 or clause 32, further comprising controlling a relative position of the chuck and a further acceptor location such that a further donor die of the one or more donor die aligns with the further acceptor location for die bonding.Clause 34: The method of any of clauses 31 to 33, further comprising extending one or more kinematic mounts toward one or more edges of the carrier for restraining movement of the carrier with respect to the chuck.Clause 35: The method of any of clauses 31 to 34, wherein activating the holding mechanism comprises delivering a fluid between the face of the chuck and a face of the carrier opposite the one or more donor dies and bringing the face of the chuck and the face of the carrier into contact with the fluid.Clause 36: The method of any of clauses 31 to 35, wherein activating the holding mechanism comprises supplying current and / or voltage to electrodes in the chuck and / or carrier, the electrodes at least partially transparent to the radiation.Clause 37: The method of clause 31, wherein the chuck comprises the chuck of any of clauses 1 to 26.Clause 38: One or more non-transitory, machine-readable medium having instructions therein, the instructions, when executed by a processor system, configured to cause the processor system to cause performance of at least the method of any of clauses 31 to 36.

[0137] While the concepts disclosed herein may be used for manufacturing with a substrate such as a silicon wafer, it shall be understood that the disclosed concepts may be used with any type of manufacturing system (e.g., those used for manufacturing on substrates other than silicon wafers).

[0138] In addition, the combination and sub -combinations of disclosed elements may comprise separate embodiments. For example, one or more of the operations described above may be included in separate embodiments, or they may be included together in the same embodiment.

[0139] The descriptions above are intended to be illustrative, not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made as described without departing from the scope of the claims set out below.

Claims

CLAIMS1. A chuck configured to hold a carrier with one or more donor dies, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier.

2. The chuck of claim 1, wherein the chuck is substantially transparent to the radiation in one or more regions corresponding to one or more areas of the carrier, the one or more areas configured for donor die placement.

3. The chuck of claim 1, wherein a mechanism configured to hold the carrier to the chuck is substantially transparent to the radiation.

4. The chuck of claim 1, further comprising an edge restraining mechanism configured to restrain the carrier at the chuck by one or more edges of the carrier.

5. The chuck of claim 1, further comprising a surface tension holding mechanism configured to hold a face of the carrier to a face of the chuck.

6. The chuck of claim 5, wherein the surface tension holding mechanism comprises a fluidbased surface tension holding mechanism.

7. The chuck of claim 5, further comprising a fluid delivery system configured to deliver a fluid between the face of the carrier and the face of the chuck.

8. The chuck of claim 5, further comprising a surface tension release mechanism.

9. The chuck of claim 8, wherein the surface tension release mechanism comprises one or more selected from: a surface deformation mechanism, a gravitational release mechanism, a pneumatic release mechanism, and / or a fluid phase change release mechanism.

10. The chuck of claim 6, further comprising a fluid removal system configured to remove a fluid between the face of the carrier and the face of the chuck.

11. A system comprising: the chuck of claim 1 ; anda positioning system configured to position the chuck and one or more donor dies held thereon relative to one or more acceptor locations.

12. The system of claim 11, further comprising a radiation emission system configured to release the one or more donor dies from the carrier towards the one or more acceptor locations.

13. A method comprising : positioning a carrier supporting one or more donor dies near a face of a chuck, the chuck being at least locally substantially transparent to radiation used for release of the one or more donor dies from the carrier; activating a holding mechanism configured to hold the carrier to the face of the chuck; and controlling a relative position of the chuck and an acceptor location such that at least one donor die of the one or more donor dies aligns with the acceptor location for die bonding.

14. The method of claim 13, further comprising causing release of the at least one donor die towards the acceptor location.

15. The method of claim 14, further comprising controlling a relative position of the chuck and a further acceptor location such that a further donor die of the one or more donor die aligns with the further acceptor location for die bonding.

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