Bond tool for die bonder and related method for use

Abstract

Bond tool for bonding a die to a target, the bond tool comprising a die-shaping element, the die-shaping element comprising an effecting surface, wherein the effecting surface is configured to contact the die and to apply a force to the die during a bond operation in which the die is bonded to the target, a support body configured to support the die-shaping element and an interface region formed between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation (Fig. 3a)

Description

[0001] BOND TOOL FOR DIE BONDER AND RELATED METHOD FOR USE

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to a bond tool, a die-shaping element for a bond tool, a support body for a bond tool, bond head, die bonder, and method of bonding a die to a target using a bond tool.

[0004] STATE OF THE ART

[0005] In the semiconductor industry, bonding of a semiconductor chip, such as a die, to a target, such as a wafer, a glass carrier, an organic substrate, an interposer, a lead frame, or the like, must be performed in a controlled manner to ensure the formation of a suitable and effective bond.

[0006] In general, a bond tool is used to bond the die to the target. In some instances, the bond tool may be used to hold the die flat during bonding. This is common where dies are bonded using glues, pastes, films or solder. In other instances, for example during die-to-wafer or die-to-die hybrid bonding or fusion bonding also known as direct bonding, such substances are not used and thus no intermediate layer is present between the die and the target. Instead, initial contact starts a bond via molecular forces. Therefore, typically, the die is bent or shaped while being held at the bond tool to provide a defined initial contact area. Once contact between die and target is initiated, a bond front or bond wave propagates from the initial contact area towards the edges of the die during such bonding.

[0007] A critical problem faced during bonding is the formation of one or more unbonded areas including voids or delaminations between the die and target after bonding. There are multiple causes for such unbonded areas.

[0008] For example, such unbonded areas may be caused by uncontrolled bond wave propagation, by particle entrapment, if multiple bond fronts collide into each other, by disruption during the propagation of a bond front, if the bond force at the edges of the die is too low at the end of the bond process, or by uncontrolled bond wave propagation. For example, such voids may also be caused if multiple bond fronts collide into each other. This may be the case if multiple initial contact points are established between the die and target and thereby multiple bond fronts may propagate therefrom. Collision of multiple bond fronts might also occur when the initial contact area is in the center of the die which starts a bond wave of a circular shape towards the edges of the die. Due to the typical rectangular shape of the dies, the bond waves reach a center point at the die edges from where they will further propagate as two bond waves towards the corners of the die where they collide together. At the same time, certain factorssuch as an uncontrolled bond front may result in edge delamination, which can also impact the quality of the bond.

[0009] Known problems in the state of the art are described below, illustrated by corresponding scenarios shown in Fig. 1a, Fig. 1b, Fig. 1c and Fig. 1d.

[0010] Fig. 1a, Fig. 1b, Fig. 1c and Fig. 1d show schematically four scenarios of a bond operation involving a conventional bond tool 10 for bonding a die 20 to a target 30 as known from the prior art. The bond tool 10 comprises an effecting surface, for effecting contact of the die 20 and the target 30. The effecting surface is the surface of the bond tool 10 which contacts the die 20 and applies force to the die 20 during the bond operation. The effecting surface is flat and is not configured to shape the die 20. In the four scenarios, two parameters are considered. A first parameter is the relative angle, also known as “tilt”, between the bond tool, which specifically the effecting surface thereof, and the target chuck, which is the component holding the target. A second parameter is die warpage.

[0011] Fig. 1a shows a first scenario. In the first scenario, tilt is zero, and die warpage is not present. In this scenario, during the bond operation, two substantially parallel to each other facing surfaces, one of surface the die 20 and one surface of the target 30, namely, are contacted with each other. In an idealised bond process for this scenario, all points of the corresponding surface of the die 20 come into contact with the corresponding surface of the target 30 at the same time, thereby creating a perfect bond. In practice, however, this is not the case. Over multiple bond operations, the initial contact area varies due to minimal changes in the mechanical conditions and due to material variations of the dies and the targets between the different bond operations.

[0012] Fig. 1b shows a second scenario. In the second scenario, tilt is zero, but die warpage is present. In this scenario, during the bond operation, multiple contact points between said facing surfaces may be established. As such, multiple bond fronts are created, resulting in formation of voids by the entrapment of gas.

[0013] Fig. 1c shows a third scenario. In the third scenario, tilt is non-zero, but die warpage is not present. In this scenario, during the bond operation, a single point of contact or a complete or partial edge contact may be established. In this schematically shown scenario, the propagationspeed of the bond wave cannot be controlled, resulting in the formation of voids which could be filled with gas or liquid due to the Joule-Thomson effect.

[0014] Fig. 1d shows a fourth scenario. In the fourth scenario, tilt is non-zero, and die warpage is present. In this scenario, any of the problematic effects described above might occur. Therefore, the quality of the bond is unpredictable and variable over multiple bond operations. In another example of a conventional approach to performing a bond operation, a bond tool may comprise an elastic, semi-adhesive element on an effecting surface of the bond tool. During contact of the die 20 with the target 30, the elastic element deforms to provide a degree of control of bond front propagation. However, this conventional approach poses numerous disadvantages. When applying increased forces on the die to flatten the elastic element, non-uniform stress is induced in the die which can result in delamination and failure at post-bonding testing, or in the field. Furthermore, the semi-adhesive nature of the elastic element leaves residues on the die surface, which is especially problematic for hybrid bonding or fusion bonding where a typical clean environment for semiconductor processing is required to ensure overall bond quality.

[0015] In general, there exists a problem that conventional approaches to bonding a die to a target are not sufficiently or suitably controllable for achieving the necessary bond quality for hybrid and fusion bonding. In general, it is desired to improve die to target, e.g., wafer, bonding, to reduce formation of voids, improve the quality of the bond, and / or to improve the accuracy of placement of a die on a target.

[0016] Furthermore, there exists a problem that the mechanical pressure distribution on the die during the bond operation is not suitably controllable. For example, in a conventional approach, the force with which the edge of the die is applied to the target at the end of the bond process may be too low. This may lead to unbonded areas in the proximity of the edge of the die.

[0017] Moreover, in a conventional approach, the rate of propagation of the force during the bond process may not be sufficiently controlled. This may lead to voids caused by gas being entrapped during the bond process of a bond operation.

[0018] Fig. 2a and Fig. 2b show schematically two scenarios involving a conventional bond tool 10 for bonding a die 20 to a target 30. The bond tool 10 comprises an effecting surface, foreffecting contact of the die 20 and target 30. The bond tool 10 comprises a rubber or other elastic element 12 which may deform when used to press the die 20 against the target 30. Fig. 2a shows a condition of the bond tool 10 prior to the bond operation. The deformable element 12 is in an initial relaxed state, and has a curved effecting surface, to provide a defined initial contact area, and has an overall substantially cylindrical or dome-shaped geometry. Fig. 2b shows a condition of the bond tool 10 during or at the end of the bond operation in which the die 20 in bonded to the target 30. During the bond operation, the deformable element 12 deforms and spreads outwardly. As indicated by the arrows in Fig. 2b, the resulting mechanical pressure distribution is inhomogeneous, i.e., is not uniform, and decreasing toward the edges of the die with a maximum mechanical pressure applied at the point of initial contact, which is toward the centre of the bond tool 10, and less mechanical pressure is applied toward outer edges of the bond tool 10. This is undesirable. In examples, this may result in delamination of die edges.

[0019] TECHNICAL PROBLEM TO BE SOLVED

[0020] It is one aim of the present disclosure, amongst others, to provide a bond tool and / or system which at least partially obviates or mitigates at least some of the disadvantages of the prior art, whether identified herein or elsewhere, or to provide an alternative approach.

[0021] BRIEF DESCRIPTION OF THE INVENTION

[0022] According to a first aspect there is provided a bond tool for bonding a die to a target.

[0023] A bond tool comprises a die-shaping element, the die-shaping element comprising an effecting surface, wherein the effecting surface is configured to contact the die and to apply a force to the die during a bond operation in which the die is bonded to the target.

[0024] A bond tool further comprises a support body configured to support the die-shaping element and an interface region formed between a frontward portion of the support body or a portion of a frontward surface of the support body and a rearward portion of the die-shaping element or a portion of a rearward surface of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

[0025] Advantageously, in this way, uniformity in the mechanical pressure distribution or a higher mechanical pressure distribution along the edges of the die than in the center during or at the end of the bond operation can be improved. Furthermore, the direction and the rate of propagation of the bond front throughout the entire bond operation can be controlled. Additionally, contact between the die and the effecting surface can be maintained throughout the entire bond operation.The die-shaping element may be elastically deformable.

[0026] In this way, the location and intensity of the force which is applied to the die during a bond operation by the die-shaping element can be changed continuously by elastically deforming the die-shaping element. In this way, following the completion of the bond operation, the dieshaping element may return to its original form.

[0027] A frontward surface of the die-shaping element may provide the effecting surface.

[0028] In this way, the die-shaping element can be used to shape the die and provide the effecting surface to effect the bond operation.

[0029] The effecting surface may be configured to shape the die to provide a bond initiation region of the die.

[0030] In this way, risk of void formation can be mitigated. Furthermore, speed and direction of the propagation of the bond front can be controlled.

[0031] The interface region may be defined by a frontward surface of the support body and a rearward surface of the die-shaping element.

[0032] The frontward surface of the support body and rearward surface of the die-shaping element may at least partially face one another.

[0033] The frontward surface of the support body may comprise a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body and into the recess.

[0034] Advantageously, by providing a recess, the die-shaping element can advantageously deform toward the support body and into the recess, thereby facilitating improved homogeneity in bond force, or enable a situation in which the bond force can actually be increased during the bond operation. Moreover, the recess can be advantageously configured to facilitate improved control of the speed and direction of the bond front.

[0035] The rearward surface of the die-shaping element may have a substantially planar profile. In this way, the construction of the bond tool may be simplified and / or improved.

[0036] The rearward surface of the die-shaping element may comprise a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body.

[0037] Advantageously, by providing a recess, the die-shaping element can advantageously deform toward the support body, thereby facilitating improved homogeneity in bond force, and / or enable a situation in which the bond force can actually be increased during the bond operation.Moreover, the recess can be advantageously configured to facilitate improved control of the speed and direction of the bond front.

[0038] The frontward surface of the support body may have a substantially planar profile.

[0039] In this way, the construction of the bond tool may be further simplified and / or improved. The support body and / or the die-shaping element may comprise each accordingly a fluid flow arrangement configured to allow fluid into or out of the interface region. The fluid flow arrangement may comprise a fluid flow channel or a gas permeable material. The fluid flow arrangement may be configured to allow fluid into or out of the interface region during the bond operation.

[0040] In this way, a mechanical pressure build-up in the interface region may be avoided, and deformation of the the die-shaping element toward the support body is enabled.

[0041] The fluid flow arrangement may be configured to cause and / or allow the surface topology of the effecting surface to be adapted.

[0042] In this way, the surface topology may be actively controlled, thereby to facilitate the shaping of the die.

[0043] The interface region may be provided by a frontward portion of the support body comprising a compressible material and / or a rearward portion of the die-shaping element comprising a compressible material, such that, during the bond operation, the die-shaping element deforms toward the support by due to force causing compression of the compressible material.

[0044] In this way, an additional or alternative construction of the support body and / or the die-shaping element may be provided.

[0045] The shape of the recess and / or of the compressible material may define the distribution of force at the effecting surface during and / or at the end of the bond operation.

[0046] In this way, the force distribution may be pre-defined, adjusted and or designed for a desired configuration.

[0047] The shape of the recess and / or of the compressible material may provide a relative increase in force toward one or more outer areas of the effecting surface during the bond operation. In this way, the risk of edge delamination may be reduced.

[0048] The die-shaping element may comprise one or more joints and / or one or more flexible regions, the joints and / or regions configured to facilitate deformation of one or more areas of the dieshaping element during the bond operation.In this way, the deformation of the die-shaping element in certain preferential areas or regions is facilitated.

[0049] The effecting surface may be configured to hold the die.

[0050] In this way, the bond wave propagation can be controlled. Furthermore, transport of the die is enabled, and requirement for additional componentry to hold the die may not be required. The bond tool may further comprise a vacuum arrangement configured to apply vacuum thereby to hold the die at the effecting surface by negative air pressure.

[0051] Advantageously, the vacuum arrangement can be used to hold the die at the effecting surface, as well as ensuring that the die is shaped by the die-shaping element. The vacuum arrangement may also contribute to ensuring that contact between the entire surface of the die and the effecting surface is maintained throughout the entire bond operation.

[0052] The form of the interface region may be configured to change in response to application of force at the effecting surface and / or before or during the application of force at the effecting surface, under control of an interface region control arrangement.

[0053] In this way, the die may be passively and / or actively shaped.

[0054] The interface region control arrangement may be configured to control the form of the interface region by application of pressure or vacuum to the fluid flow channel.

[0055] In this way, the die may be actively shaped.

[0056] The die-shaping element may comprise an elastomer part, wherein the elastomer part is providing the effecting surface, or a metal part, the metal part providing the effecting surface, or an elastomer part and a metal part, the metal part provided on the elastomer part, the metal part providing the effecting surface. Advantageously, in case of both, an elastomer part and a metal part, the elastomer part may support the metal part.

[0057] Where the die-shaping element comprises a metal part, or a metal part provided on an elastomer part, advantages are realised in improving cleanliness of the bond operation. Contamination of the die, and risk of die failure (in operation, or due to quality control) can thereby be avoided or reduced.

[0058] The effecting surface may comprise a texture provided thereon for reducing a level of adhesion between the die and the effecting surface.

[0059] This is highly advantageous in reducing adhesion between the die and the effecting surface, such that the bond tool can be brought away from the bonded die without risk of disrupting the bond.According to a second aspect there is provided a die-shaping element for a bond tool for bonding a die to a target, the die-shaping element configured to be supported by a support body, the die-shaping element comprising an effecting surface, wherein the effecting surface is configured to contact the die and to apply a force to the die during a bond operation in which the die is bonded to the target. Additionally, an interface region is formed between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

[0060] In this way, the die-shaping element can be provided in isolation, which is highly advantageous in improving existing tools by retrofit.

[0061] According to a third aspect there is provided a support body for a bond tool for bonding a die to a target, the support body configured to support a die-shaping element comprising an effecting surface, wherein the effecting surface is configured to contact the die and to apply a force to the die during a bond operation in which the die is bonded to the target; wherein an interface region is defined between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

[0062] In this way, the support can be provided as such as a standalone supportwithout a die-shaping element, which is highly advantageous in improving existing tools by retrofit.

[0063] According to a fourth aspect there is provided a bond head comprising the bond tool according to the first aspect, die-shaping element according to the second aspect, or support body according to the third aspect.

[0064] In this way, the bond operation performed using the bond head is improved.

[0065] According to a fifth aspect there is provided a die bonder comprising the bond tool according to the first aspect, die-shaping element according to the second aspect, support body according to the third aspect, or bond head according to the fourth aspect.

[0066] In this way, the bond operation performed using the die bonder is also improved.

[0067] The die bonder may further comprise a metrology device configured to perform imaging thereby to determine one or more characteristics of the die when the die is held at the effecting surface.

[0068] In this way, one or more characteristics of the die can be determined. Advantageously, the die held at the effecting surface can be imaged before the bond operation.According to a sixth aspect there is provided a method of bonding a die to a target using a bond tool as disclosed herein. The method comprises the steps of contacting the die with the effecting surface, applying force to the die to bond the die to the target, wherein during applying force at the effecting surface during the bond operation the die-shaping element is deformed toward the support body.

[0069] In the method, as disclosed herein, the interface region may be defined by a frontward surface of the support body and a rearward surface of the die-shaping element, wherein the frontward surface of the support body comprises a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body and into the recess, and / or wherein the rearward surface of the die-shaping element comprises a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body, or wherein the interface region is provided by a frontward portion of the support body comprising a compressible material, and / or a rearward portion of the die-shaping element comprising a compressible material, such that, during the bond operation, the die-shaping element deforms toward the support by due to force causing compression of the compressible material.

[0070] In the method, the rate of propagation of the bond front may be determined by the interface region, wherein the interface region is preferably determined by the shape of the recess and / or by the compressibility of the material of the die-shaping element and / or of the support body. The method may comprise controlling the rate of propagation of the bond front throughout the entire bond operation.

[0071] The method may comprise maintaining contact between an entire surface of the die and the effecting surface throughout the entire bond operation.

[0072] The method may comprise maintaining a substantially constant level of vacuum on a rearward surface of the die throughout the entire bond operation.

[0073] The method may comprise applying / controlling a force to the die at the end of the bond operation with a force distribution which is homogenous across the die surface or increasing towards the edges of the die.

[0074] The target of the bond tool, bond head, die-shaping element, support body, or die bonder according to any aspect, may be one or more of a die, a stack of dies, a package, a substrate, an interposer, a lead frame or a wafer.

[0075] It will be appreciated that in most or all instances, features described in relation to one aspect of the invention may be used in combination with, or in place of, one of more features described in relation to one or more other aspects of the invention.BRIEF DESCRIPTION OF THE DRAWINGS

[0076] For a better understanding of the invention, and to show how embodiments of the same may be brought into effect, reference will be made, by way of example only, to the accompanying Figures, in which:

[0077] Fig. 1a, Fig. 1b, Fig. 1c and Fig. 1d show four scenarios involving a conventional bond tool;

[0078] Fig. 2a, Fig. 2b shows a scenario involving a conventional bond tool;

[0079] Fig. 3a, Fig. 3b and Fig. 3c show use of a bond tool in a bond operation;

[0080] Fig. 4 shows a bond tool having a die-shaping element comprising a metal part;

[0081] Fig. 5 shows a flowchart;

[0082] Fig. 6a, Fig. 6b and Fig. 6c show use of a bond tool during die-shaping;

[0083] Fig. 7 shows a die-shaping element;

[0084] Fig. 8 shows a support body;

[0085] Fig. 9 shows a schematic bond head;

[0086] Fig. 10 shows a schematic die bonder;

[0087] Fig. 11 shows general methodology principles.

[0088] DETAILED DESCRIPTION OF THE INVENTION

[0089] The present invention primarily relates to die to target (e.g., a wafer) or die to die hybrid or fusion bonding. In examples, no intermediate layer may be present between the die and the target. For example, no adhesive may be employed. This approach is distinct from thermocompression, which may be utilised in conventional semiconductor manufacture. The present invention looks to improve the bond operation to address one or more of the problems discussed above, or discussed elsewhere. That is, the present invention looks to improve the operation or process in which a die is brought into contact with, and is bonded to, a target. In particular, the present invention looks to facilitate an improvement in the reduction of unbonded areas between the die and target which may occur during the bond operation. Furthermore, the present invention looks to facilitate an improvement in mechanical force, or mechanical pressure distribution during the bond operation.

[0090] The description herein describes a number of examples in which a die is bonded to a target, and in particular where the target is a wafer. However, the target may have an alternative form,or plurality of alternative forms. That is, the bond tools, systems, bond heads, die bonders and / or methods described herein may be utilised to bond, or during the bonding of, a die to a variety of possible targets. Examples of suitable targets include one or more of a die, i.e. , an additional die, a stack of dies, a package, a substrate, e.g., an organic or inorganic substrate, an interposer, a lead frame, a glass carrier, and / or a wafer. In general, “die to wafer” bonding is described in the description which follows, but it will be readily appreciated to the skilled person how the invention may be employed when a target is one of the alternatives described here or elsewhere.

[0091] As a general overview of operation, and applicable to all examples of bond tools described herein, during the bond operation, the bond tool contacts a die, at a rear surface of the die. The bond tool, holding the die, is moved toward, e.g., vertically down toward, a target. The front surface of the die makes initial contact with the target at a bond initiation region. The bond initiation region may be provided by appropriate shaping of the die as described in detail herein. As the bond tool continues to move toward the target, the area of contact of the front surface of the die with the target is increased. This step is also known as bond front propagation. Eventually, by the approaches described herein, when the entire front surface of the die is in contact with the target, the die will be pressed against the target. The present invention looks to improve the distribution of the force by which the die is bonded to the target. For example, by applying force homogeneously across the die surface or by applying an increasing force distribution towards the edges of the die.

[0092] In Fig. 3a, Fig. 3b and Fig. 3c, use of a bond tool 100 is schematically shown during a bond operation. As shown in Fig. 3a, Fig. 3b and Fig. 3c, the bond tool 100 is for bonding a die 200 to a target 300. The bond tool 100 comprises a support body 110. The support body 110 is configured to have a die-shaping element provided thereon. The support body 110 may be configured to receive a die-shaping element. The support body 110 may be configured to hold a die-shaping element.

[0093] The bond tool 100 further comprises a die-shaping element 120. A die-shaping element 120 is an element configured to shape a die 200 when the die 200 is received, or held, by the bond tool 100.

[0094] The die-shaping element 120 comprises an effecting surface 130. The effecting surface 130 is configured to contact to die 200. The effecting surface 130 may be configured to hold the die 200.

[0095] The effecting surface 130 is configured to shape the die 200, by at least the die-shaping element 120. That is, at least the die-shaping element 120 provides some shaping of the die 200. In other words, the die-shaping element 120 is configured to influence the shape or formof the die. By the presence of at least the die-shaping element 120, the effecting surface is the surface which shapes the die.

[0096] The effecting surface 130 is configured to apply a force to the die 200 during a bond operation in which the die 200 is bonded to the target 300. In other words, the effecting surface 130 is the surface which applies forced to the die during bonding of the die 200 to the target 300. The effecting surface may be only the region of the die-shaping element 120 which is in contact with, or is configured to be in contact with, the die 200 during the bond operation.

[0097] The bond tool 100 further comprises an interface region 140. The interface region 140 is defined between a frontward portion of the support body 110 and a rearward portion of the die-shaping element 120. The interface region 140 is configured to allow the die-shaping element 120 to deform toward the support body 110 due to force on the die-shaping element 120 during the bond operation.

[0098] The provision of such an interface region 140 is a notable distinction over conventional bond tool design. By facilitating deformation of the die-shaping element 120 toward the support body 110, uniformity in the mechanical pressure distribution during or at the end of the bond operation can be improved, or a higher mechanical pressure distribution along the edges of the die than in the centre of the die can be achieved.

[0099] Deformation of the die-shaping element 120 toward the support body 110 can be achieved in various ways, whereas corresponding examples of realisations thereof are described herein after.

[0100] For example, deformation of the die-shaping element 120 toward the support body 110 may include the die-shaping element 120, or a portion thereof, moving into a recess provided in the support body 110.

[0101] Or, for example, deformation of the die-shaping element 120 toward the support body 110 may include the provision of suitable materials, e.g., flexible, compressible, or deformable materials to enable such deformation. It will be appreciated that by the interface region 140 being defined between the frontward portion of the support body 110 and the rearward portion of the die-shaping element 120, the interface region 140 may not necessarily be at, i.e. , exactly at, a frontward surface of the support body 110 and a rearward surface of the die-shaping element 120. Instead, the interface region 140 may include said surfaces, or portions thereof, but may also incorporate other parts of the support body 110 and die-shaping element 120. Therefore, the frontward portion of the support body 110 may be a portion toward the front of the support body 110 or a portion of the front surface of the support body 110, and the rearward portion of the die-shaping element 120 may be a portion toward the rear of the die-shaping element 120 or a portion of the rear surface of the die-shaping element 120.Or, for example, the frontward portion or surface of the support body 110 and rearward portion or surface of the die-shaping element 120 substantially face one another.

[0102] Or, for example, regions of material may be incorporated which are relatively more deformable than surrounding materials, thereby allowing for deformation of the die-shaping element 120 toward the support body 110 in the described manner. In this way, an appropriate interface region may be defined.

[0103] The effecting surface 130 may be configured to shape the die 200 to provide a bond initiation region 210 of the die 200. The bond initiation region 210 may be a region of the die 200 which is shaped by the effecting surface 130 to have a single point of contact or a line of contact or an area of contact with the target 300 when the die is first brought into contact with the target 300. In this way, the bond front otherwise known as the bond wave can be controlled. The bond initiation region 210 is a result of the shaping by the effecting surface 130, in particular by the die-shaping element 120, rather than due to inherent shaping of the die 200 such as being due to die warpage.

[0104] As described above, inherent die-shaping due to die warpage is problematic, as void entrapment may result during a bond operation if a die is not appropriately shaped. The bond initiation region 210 is significantly smaller than the entire contact surface of the die 200. The die-shaping element 120 may be elastically deformable. In this way, the location and intensity of the force which is applied to the die 200 during a bond operation by the die-shaping element 120 can be changed continuously by elastically deforming the die-shaping element 120. In this way, the die-shaping element 120 may be deformed due to force applied thereon during the bond operation. Following the completion of the bond operation, the die-shaping element 120 may return to its original form, thereby to shape a further die 200 in a subsequent bond operation. The die-shaping element 120 may be at least partially or in whole elastically deformable.

[0105] A frontward surface 122 of the die-shaping element 120 may provide the effecting surface 130. That is, the frontward surface 122 of the die-shaping element 120 provides the effecting surface 130 to contact the die 200, and, during the bond operation, apply the required force to the die 200 to bond the die 200 to the target 300.

[0106] Fig. 3a shows the state of the bond tool 100 before or at the beginning of the bond operation. Fig. 3b shows the state of the bond tool 100 during the bond operation. Fig. 3c shows the state of the bond tool 100 at, or toward, the end of the bond operation. Features of the bond tool 100 referenced below may be indicated in Fig. 3a, Fig. 3b and Fig. 3c for clarity of the drawings, although it will be appreciated that corresponding features are present in all three Illustrations of Fig. 3a, Fig. 3b and Fig. 3c.In all three Illustrations of Fig. 3a, Fig. 3b and Fig. 3c, the interface region 140 may be defined by a frontward surface 112 of the support body 110 and a rearward surface 124 of the dieshaping element 120. That is, the configuration of the frontward surface 112 of the support body 110 and / or of the rearward surface 124 of the die-shaping element 120 may define the interface region 140.

[0107] In this example, the frontward surface 112 of the support body 110 comprises a recess 114. The recess 114 has a semi-circular cross section. The recess 114 may have a hemi-spherical, or domed, three-dimensional form. The recess 114 may alternatively have a hemi-cylindrical form. The recess 114 may be provided in, or at, the support body 110. That is, the recess 114 extends into the support body.

[0108] Referring to Fig. 3a, before or at the beginning of the bond operation, the die 200 is held at the effecting surface 130 and is brought into contact with the target 300. The recess 114 provides a space into which the die-shaping element 120 can deform, or be pressed into, during the bond operation.

[0109] Referring to Fig. 3b, during the bond operation, the bond tool 100 is moved in a tool bond movement direction, e.g., a downward direction, as indicated by arrow 102. The bond tool 100 is moved toward the target 300, to bring the die 200 into contact with the target 300. Applying of force at the effecting surface 130 causes the die-shaping element to deform toward the support body 110 and into the recess 114. In other words, during the bond operation, the die 200 is brought into contact with the target 300 and force of the bond operation causes the dieshaping element 120 to be deformed, pushed, or pressed into the recess 114. For avoidance of doubt, the entirety of the die-shaping element is not deformed into the recess 114, but rather a part of the die-shaping element 120 may be pressed rearwardly into the recess 114.

[0110] Referring to Fig. 3c, at, or toward, the end of the bond operation, the effecting surface 130 is brought into a flat, or planar, form to press the die 200 against the target 300. Notably, as indicated by the upward arrows in Fig. 3c, the mechanical pressure distribution across the die 200 is uniform, or at least is more uniform than conventional approaches which do not look to incorporate the interface region 140 considered here or any interface region as described herein.

[0111] As illustrated in in all three Illustrations of Fig. 3a, Fig. 3b and Fig. 3c, the rearward surface 124 of the die-shaping element 120 has a substantially planar profile. That is, the rearward surface 124 of the die-shaping element 120 has a substantially planar profile when the dieshaping element 120 is in an undeformed state. That is, the rearward surface 124 of the dieshaping element may be flat. It will be appreciated that the planar or flat surface 124 of the die-shaping element may be a portion of the rearward surface 124 which corresponds with therecess 114. The recess 114 is provided in the support body 110, thereby providing a space into which the die-shaping element 120 can be deformed or pressed.

[0112] However, in another example, which may be an alternative, the rearward surface 124 of the die-shaping element 120 may instead, or additionally, comprise a recess. The bond operation, and deformation of the die-shaping element 120 toward the support body 110 may occur in a similar manner to that described above. Namely, the die-shaping element 120 will deform toward the support body 110. However, rather that the die-shaping element deforming into the recess, the recess instead acts as a space into which the die-shaping element 120 is preferentially deformed. In this example, the frontward surface 112 of the support body 110 may have a substantially planar profile. Advantageously, such an approach may reduce the need to adapt or modify construction of a support body 110, which is particularly advantageous in retrofit of the bond tool 100 to provide the interface region 140.

[0113] The support body 110 and / or the die-shaping element 120 may comprise a fluid flow arrangement, as illustrated in Fig. 3a, Fig. 3b and Fig. 3c. In an example, the fluid flow arrangement 150 is provided in, or through, the support body 110 and communicates with the interface region 140. The fluid flow arrangement 150 is configured to allow fluid into or out of the interface region 140. The fluid flow arrangement 150 may be configured to allow fluid into or out of the interface region 140 during the bond operation. The fluid flow arrangement 150 may be referred to as an exhaust.

[0114] In further detail, during deformation of the die-shaping element 120, mechanical pressure build-up may occur due to force thereon during the bond operation. The fluid flow arrangement 150 may allow gases or fluids to be released from e.g., the recess 114 within the bond tool 100 during the bond operation. The fluid flow arrangement 150 may provide one or more fluidic communication passages between the recess 114 and the ambient environment.

[0115] The fluid flow arrangement 150 may be of any suitable construction. However, in advantageous examples, the fluid flow arrangement 150 may be, or include, one or more fluid flow channels and / or gas permeable materials. In an example, the support body 110 and / or the die-shaping element 120 may be formed of a gas permeable material.

[0116] The fluid flow arrangement 150 may be configured to cause and / or allow the surface topology of the effecting surface 130 to be adapted. Where the fluid flow arrangement 150 allows the surface topology of the effecting surface 130 to be adapted, the fluid flow arrangement 150 may be a passive arrangement, allowing fluid into or out of the interface region 140 during the bond operation, but not “actively” controlling the surface topology or change thereof. In an active control of the surface topology, thereby to cause adaptation of the surface topology, the fluid flow arrangement 150 may be used to apply pressure, e.g., positive or negative pressure,into the interface region, to act on the die-shaping element 120 to cause outward or inward deformation of the effecting surface 130. In an active approach, the fluid flow arrangement 150 may be used in conjunction with an interface region control arrangement as described herein. This is highly advantageous in controlling shaping of the die 200 when it is held at the effecting surface 130.

[0117] The form of the interface region 140 may be configured to change in response to application of force at the effecting surface 130. That is, force at the effecting surface 130 during the bond operation causes the die-shaping element 120 to deform, thereby changing the form or shape of the interface region 140.

[0118] Additionally, or alternatively, the form of the interface region 140 may be configured to change before or during the application of force at the effecting surface 130. The form of the interface region 140 may change under control of an interface region control arrangement 152. The interface region control arrangement 152 may be configured to generate negative or positive pressure in the interface region 140. The interface region control arrangement 152 may include one or more pumps. The interface region control arrangement 152 may be configured to control the form of the interface region 140 by application of pressure or vacuum to the fluid flow channel 150.

[0119] The bond tool 100 may further comprise a vacuum arrangement 160. The vacuum arrangement 160 is configured to apply vacuum thereby to hold the die 200 at the effecting surface by application of negative pressure. The vacuum arrangement 160 may comprise one or more fluid channels by which vacuum can be used to hold the die 200 at, and against, the effecting surface 130. Advantageously, the vacuum arrangement 160 can be used to hold the die 200 at the effecting surface 130, as well as ensuring that the die 200 is shaped by the dieshaping element 120. The vacuum arrangement 160 may also contribute to ensuring that contact between the entire surface of the die 200 and the effecting surface 130 is maintained throughout the entire bond operation.

[0120] Whilst not illustrated in any of Fig. 3a, Fig. 3b and Fig. 3c, during the bond operation the vacuum arrangement 160, specifically the fluid channels (not labelled with an explicit numeral) of the fluid flow arrangement 150 thereof, may bend to account for the deformation of the dieshaping element 120.

[0121] As shown in Fig. 3a, Fig. 3b and Fig. 3c, the die-shaping element 120 may comprise one or more joints 126 and / or one or more flexible regions, the joints 126 and / or regions configured to facilitate deformation of one or more areas of the die-shaping element 120 during the bond operation. The joints 126 and / or regions are configured to allow preferential deformation ofthe die-shaping element 120 at the location of the joints 126 and / or regions due to the force experienced during the bond operation.

[0122] In examples, a rigidity of the material from which the die-shaping element 120 is formed in at least the region of the effecting surface 130 is defined by a value of shore hardness of about 45 or above. Preferably, the value of shore hardness is about 55 or above. More preferably, the shore hardness is about 60 or above. Most preferably, the shore hardness is about 65 or above. By the present disclosed construction, a die-shaping element 120 having a higher shore hardness can be utilised, reducing issues relating to stickiness of materials having lower shore hardness, but uniformity of mechanical pressure distribution can nevertheless by achieved due to the bond tool 100 incorporating the interface region 140 according to examples described herein.

[0123] As mentioned above, the die-shaping element 120 may be elastically deformable. In an example, as illustrated in Fig. 3a, Fig. 3b and Fig. 3c, the die-shaping element 120 is formed of a single part or piece. The die-shaping element 130 may be formed of an elastomer. That is, the die-shaping element 130 comprises an elastomer part, and the entire die-shaping element may be formed of the elastomer part. The elastomer part may provide the effecting surface 130.

[0124] However, alternative constructions of the die-shaping element 120 are possible, and consistent with the scope of the invention.

[0125] In an example of an alternative construction, the die-shaping element 120 may be formed of a metal part. That is, the entire die-shaping element 120 may be formed of the metal part. The metal part may provide the effecting surface 130. The metal part may be elastically deformable, as described above.

[0126] Referring to Fig. 4, a further example of an alternative construction of the die-shaping element 120 is shown. The die-shaping element 120, and in particular the bond tool 100 as a whole, is substantially identical to that described and illustrated with reference to Fig. 3, apart from the differences described below.

[0127] In this example, the die-shaping element 120 comprises an elastomer part 127 and a metal part 128. The metal part 128 is provided on the elastomer part 127. The metal part 128 may be provided on a frontward surface of the elastomer part. The metal part 128 provides the effecting surface 130. Operation of the die-shaping element 120 is identical to that described above in relation to any of Fig. 3a, Fig. 3b and Fig. 3c. That is, the die-shaping element 120, in particular including the metal part 128 and the elastomer part 127, deforms toward the support body 110 during the bond operation. However, utilising a metal part 128 to provide the effecting surface 130 is highly advantageous. Elastomers, e.g., rubbers, may leaveparticles on the surface of the die 200 following the bond operation. This can be avoided by use of the metal part 128, improving cleanliness of the bond operation. Contamination of the die 200, and risk of die failure in operation, or due to quality control can thereby be avoided or reduced.

[0128] The effecting surface 130 may comprise a texture provided thereon for reducing a level of adhesion between the die 200 and the effecting surface 130. That is, a texture or pattern, may be applied (e.g., by laser etching) to the effecting surface 130. This is highly advantageous in reducing adhesion between the die 200 and the effecting surface 130, such that the bond tool 100 can be brought away from the bonded die without risk of disrupting the bond. The texture may increase a roughness value of the effecting surface 130. The texture may alternatively be referred to as a surface preparation. A texture can be applied to any effecting surface 130. That is, a texture can be applied to any effecting surface 130 described herein, whether the effecting surface 130 is provided by an elastomer part or a metal part. However, in conjunction with a construction in which the effecting surface 130 is provided by a metal part 128, this is highly advantageous as the metal part 128 can be textured and cleaned, i.e., to remove particles due generated during the texturing, more effectively than an elastomer part.

[0129] Whilst the examples described thus far make use of a recess 114, alternative, or additional, constructions may be utilised in enabling the die-shaping element 120 to deform toward the support body 110 during the bond operation.

[0130] The interface region 140 may be provided by a frontward portion of the support body 110 comprising a compressible material. Additionally, or alternatively, the interface region 140 may be provided by a rearward portion of the die-shaping element 120 comprising compressible material. In this way, during the bond operation, the die-shaping element 120 deforms toward the support by due to force causing compression of the compressible material. The compressible material may be relatively more compressible than other regions or portions of the support body 110 and / or die-shaping element 120. In an example, the compressible material may be a sponge-like material. Said portions comprising compressible material may be regions of the support body 110 and / or of the die-shaping element 120.

[0131] The support body 110 and / or the die-shaping element 120 may have a piece of compressible material provided in said portions or regions. That is, a compressible material may be embedded in a frontward portion of the support body 110 and / or in a rearward portion of the die-shaping element 120. Alternatively, the frontward portion of the support body 110 and / or rearward portion of the die-shaping element 120 may be formed of a compressible material. In an example, additive layer manufacturing may be utilised to manufacture the support body 110 and / or die-shaping element 120 to have a varying compressibility.By such a construction, the interface region 140 facilitates preferential deformation thereat, by virtue of the provision of a portion of the support body 110 and / or of the die-shaping element 120 having a relatively higher compressibility. The relatively higher compressibility may be relative to other portions or regions of the support body 110 and / or of the die-shaping element 120, so that the deformation occurs primarily, if not solely, at those portions or regions.

[0132] The use of compressible materials may be instead of, or may be in combination with, the use of recesses as described above. By using compressible materials, recesses may not be required, and the construction and operation of the bond tool 100 may be simplified. Preferably, therefore compressible materials with a compression module below one GigaPascal of are used.

[0133] More generally, the shape of the recess 114 and / or of the compressible material may define the distribution of force at the effecting surface 130 during and / or at the end of the bond operation. The recess 114 and / or compressible material are selected, sized, shape, or otherwise configured so that the force distribution during and / or at the end of the bond operation is preferably uniform or homogeneous or results in an increasing force distribution towards the edges of the die, i.e., toward the end of the bond operation. In each of Fig. 3a, Fig. 3b and Fig. 3c, this is illustrated by the uniformly sized arrows 400, which notably contrast with the non-uniform, or inhomogeneous, force distribution of the prior art example described with reference to Fig. 2. This may be achieved by corresponding, but opposite, shaping of the die-shaping element 120 and the recess 114, or by appropriately positioning or shaping of the compressible material.

[0134] The shape of the recess 114 and / or of the compressible material may provide a relative increase in force toward one or more outer areas of the effecting surface 130 during the bond operation. In such a construction, the force distribution may not be homogeneous, but instead outer edges of the die 200 may be pressed against the target 300 with increased force. Advantageously, this reduces risk of die edge delamination. The recess 114 may be appropriately shaped in order to provide such a force distribution, for example by reduced gradient, or a step, towards lateral edges of the recess 114. In an example, the shape of the recess 114 and / or of the compressible material may be such that the bond front begins at a central point and initially propagates with a substantially circular bond front across the target. However, the recess 114 and / or compressible material may be arranged such that, subsequently, the bond front propagates with a rectangular-shape toward the die edges. This can facilitate improve bond quality toward edges or corners of the die, and may be advantageous in ensuring good bond quality in die-stacking operations.Further details of the bond tool 100 will be described in relation to a description of operation and function thereof during a die pick-up and die bond operation. In the description which follows, operation and function will be described in relation to a bond tool comprising a recess 114 formed in the support body 110. Nevertheless, it will be appreciated by the skilled person that the general teaching is applicable to examples where the bond tool 100 comprises a recess 114 formed, for example, in the die-shaping element 120, or where the interface region 140 is defined by portions or regions of compressible material.

[0135] The description will be provided with reference to Fig. 5 illustrating the method steps 502 to 520.

[0136] In a first optional step 502 the surface topology of the die-shaping element 120 may be adapted for die picking. The interface region control arrangement 150 may be utilised to apply vacuum thereby to adapt a surface topology of the effecting surface 130. The interface region control arrangement 150 may cause the die-shaping element 120 to deform toward the support body 110. The interface region control arrangement 150 may cause the effecting surface 130 to adopt a planar form.

[0137] In the step 504, the bond tool 100 is moved to a position to pick a die 200. To pick the die 200, the effecting surface 130 may be brought toward and into contact with the die 200 to collect it from a carrier or flip tool. The vacuum arrangement 160 may apply vacuum thereby to hold the die 200 at the effecting surface 130 by negative pressure. Die-picking techniques are well-known in the art. Notably, and distinct from the prior art, the application or pressure or vacuum on the rearward surface of the die 200 by the vacuum arrangement 160 is maintained throughout the entire bond operation.

[0138] In step 506, alignment may be performed to calculate a target position for the die 200 for the particular situation. In an example, a metrology device may be employed to image the bond tool for determining one or more characteristics of the die 200 held at the effecting surface. The one or more characteristics of the die 200 may include determining the shape of the die, the location of the die relative to the bond tool, die-shaping properties of the die, the surface properties of the die, or further characteristics known to a person skilled in the art.

[0139] In embodiments of die-bonder, the output from the metrology device may preferably be used to determine the target position.

[0140] In step 508, the bond tool 100, with die 200 held at the effecting surface 130, is moved to the target position.

[0141] In step 510, in an optional step, the shape of the effecting surface 130 of the die-shaping element 120 may be changed or adapted, in preparation for the bond operation. In anexample, this may be performed by adapting the pressure in the recess 114 of the interface region 140. The interface region control arrangement 150 may be utilised. In other words, the interface region control arrangement 150 may control the form of the interface region 140. The interface region control arrangement 150 may be configured to change the form of the interface region before or during the application of force at the effecting surface 130, i.e., before or during the bond operation. The interface region control arrangement 150 may be configured to control the form of the interface region 140, and thus the effecting surface, by application of pressure or vacuum to the fluid flow channel, as described above.

[0142] By introducing fluid, e.g., air, into the recess 114, the pressure therein is increased so as to cause the die-shaping element 120 to project outwardly, or more outwardly. Conversely, by removing fluid, e.g., air, from the recess 114, the pressure therein is decreased so as to cause the die-shaping element 120 to project less outwardly. In this way, the die 200 can be shaped prior to the bond operation.

[0143] In step 512, the bond tool 100 is moved in the tool bond movement direction 102, e.g., downwardly in the vertical direction. The die 200 is brought into contact with the target 300. The initial contact is made at the bond initiation region 210, as described above.

[0144] In step 514, the bond tool 100 is continued to be moved in the tool bond movement direction 102. The bond front propagates outwardly. As described above, during the bond operation, the die-shaping element 120 moves toward the support body 110 and is forced into the recess 114. The speed of the bond front propagation may be controlled by shape of the recess 114 or by the compressibility of the material of the die-shaping element 120 and / or the support body 100 or by the by the speed with which the bond tool 100 is moved downwardly, or by any combination thereof. In addition, the vacuum arrangement 160 maintains, e.g., a substantially constant level of pressure or vacuum on the rearward surface of the die 200 throughout the entire bond operation. That is, at no point does the die 200 become released from contact with the effecting surface 130.

[0145] As the die-shaping element 120 is forced into the recess 114, contact between the rearward surface of the die-shaping element 120 and the frontward surface of the support body 110, i.e., with the surface of the recess 114, defines, or at least influences, the pressure distribution of the bonding of the die 200 with the target 300.

[0146] In particular, the shape of the recess 114 and / or the shape of the compressible material may define the distribution of force at the effecting surface 130 during and / or at the end of the bond operation.

[0147] In greater detail, in the case of a recess 114, the shape or form thereof may define the pressure distribution on the die 200 during the bond operation. As mentioned above, the recess 114typically has the form of a domed indentation, i.e., having a semicircular cross section, which may be provided in the frontward surface of the support body 110. The recess 114 may have a shape which is the negative shape of a frontward projecting region of the die-shaping element 120. During the bond operation, the die-shaping element 120 is deformed toward the support body 110, and may adopt a planar form once the bond front has propagated outwardly across the full extent of the die 200. Highly advantageously, when this occurs, the pressure distribution across the die 200 is homogeneous or uniform or increasing towards the edges of the die 200.

[0148] In an example, the shaping of the recess and / or of the compressible material provides a relative increase in force toward one or more outer areas of the effecting surface 130 during the bond operation. For example, the recess 114 may have a form in which regions toward the circumference of the recess 114 are configured to provide less space for the die-shaping element 120 to be moved rearwardly. This results in a pressure distribution in which the edges of the die are pressed with greater force that the centre of the die. Advantageously, in this way, risk of delamination at edges of the die 200 can be reduced. This is highly advantageous where die stacking is performed.

[0149] The rate of propagation of the bond front, that is, the outer line or contour of contact between the die 200 and the target 300, is controlled throughout the entire bond operation. Contact is maintained between the entire surface, in particular the rearward surface, of the die 200 and the effecting surface 130 throughout the entire bond operation. The vacuum arrangement 160 maintains pressure or vacuum on the rearward surface of the die 200 throughout the entire bond operation.

[0150] In step 516, once the full extent of the die 200 is in contact with the target 300, the bond tool 100 may be held at that position for a desired length of time. Pressure is applied to the die 200 and a secure bond is formed between die 200 and target 300.

[0151] In step 518, in an optional step, where a vacuum arrangement 160 is used to hold the die 200 at the effecting surface 130 by negative pressure, the vacuum arrangement 160 may be controlled to release the die 200. That is, vacuum may be switched off, thereby to release the die 200. However, if a vacuum arrangement is not utilised, e.g., if the die is held at the effecting surface 130 by an adhesion property of the material of the effecting surface 130, or if electrostatic force is used to hold the die 200 at the effecting surface 130, or an adhesive or other means are used to hold the die 200 at the effecting surface 130, no action may need to be taken to release the die.

[0152] In step 520, the bond tool 100 is moved in a direction opposite to the tool bond movement direction 102, in particular upwardly in a vertical direction, away from the target 300. The die-shaping element 130 separates from the die 200 and the die 200 remains bonded to the target 300.

[0153] The process may be repeated to bond further dies to the target 300, or to bond a further die to a new target 300.

[0154] With reference to any of Fig. 6a, Fig. 6b and Fig. 6c, an alternative approach of a bond tool 100’ is shown comprising a die-shaping element 120’. Fig. 6a, Fig. 6b and Fig. 6care provided, accordingly, as an alternative approach for die-shaping claimed on the same day as this invention is filed as patent application DE 102025 103083.9 on 28thJanuary 2025 by the same applicant and is incorporated by reference hereto into this disclosure as to the one illustrated Fig. 3a, Fig. 3b and Fig. 3c only to illustrate the differences hereto.

[0155] As shown in Fig. 6, a die 200’ is shaped by the die-shaping element 120’. The die-shaping element 120’ is in the form of a plunger. The die-shaping element 120’ provides only part of an effecting surface 130’, with another part being provided by a support body 110’. The dieshaping element is not deformable. During a bond operation, the die-shaping element 120’ retracts into the support body 110’. It will be appreciated that as the die-shaping element 120’ retracts, the die 200 can be forced through sharp angles, in particular where a vacuum arrangement 160’ is used to hold the die 200 at the effecting surface 130’. For example, as the die-shaping element is brought into the configuration shown in Fig. 6b, the die 200’ may be pulled around the plunger, risking damage to the die 200’. Furthermore, it will be appreciated that the force distribution on the die 200’ in Fig. 6c may be inhomogeneous. The present approach as illustrated by Fig. 3a, Fig. 3b and Fig. 3c is improved over that as illustrated in Fig. 6a, Fig. 6b and Fig. 6c in numerous ways, but at least by support of the full rearward surface of the die 200, enablement of homogeneous force distribution, and ensuring reduction in unbonded areas due to control of propagation of the bond front.

[0156] Referring to Fig. 7, the die-shaping element 120 is shown in isolation. The die-shaping element 120 may comprise any or all of the features of the die-shaping element 120 described above, as desired or as appropriate. The die-shaping element 120 is for a bond tool 100 for bonding a die 200 to a target 300.

[0157] The die-shaping element 120 is configured to be supported by a support body 110. The dieshaping element 120 comprises an effecting surface 130. The effecting surface 130 is configured to contact the die and to apply a force to the die during a bond operation in which the die is bonded to the target.

[0158] An interface region 140 is formed between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region is configured to allowthe die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

[0159] Referring to Fig. 8, the support body 110 is shown in isolation. The support body 110 may comprise any or all of the features of the support body 110 described above, as desired or as appropriate. The support body 110 is for a bond tool 100 for bonding a die 200 to a target 300. The support body 110 is configured to support a die-shaping element 120 comprising an effecting surface 130. The effecting surface 130 is configured to contact the die 200 and to apply a force to the die during a bond operation in which the die is bonded to the target. An interface region 140 is defined between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region 140 is configured to allow the die-shaping element 120 to deform toward the support body 110 due to force on the die-shaping element during the bond operation.

[0160] Referring to Fig. 9, a bond head 900 is shown. The bond head 900 comprises a bond tool 100, die-shaping element 120, or support body 110. The bond head 900 may comprise any or all of the features of the bond tool, die-shaping element 120, or support body 110, as described above, as desired or as appropriate.

[0161] Referring to Fig. 10, a die bonder 1000 is shown. The die bonder comprises a bond tool 100, a die-shaping element 120, a support body 110, or a bond head 900, according to any of the examples described herein.

[0162] The die bonder 1000 may comprise a metrology device configured to perform imaging thereby to determine one or more characteristics of the die when the die is held at the effecting surface 130. The die bonder may image the die 200 when held at the effecting surface 130.

[0163] Referring to Fig. 11, a method of bonding a die to a target using a bond tool is shown.

[0164] The bond tool may be according to any of the examples described herein.

[0165] In particular, the bond tool comprises a die-shaping element, the die-shaping element comprising an effecting surface, wherein the effecting surface is configured to: contact the die; and apply a force to the die during a bond operation in which the die is bonded to the target. The bond tool further comprises a support body configured to support the die-shaping element. The bond tool further comprises an interface region formed between a frontward portion of the support body or a portion of the front surface of the support body and a rearward portion of the die-shaping element or a portion of the rear surface of the die-shaping element.

[0166] Step S1110 comprise contacting the die with the effecting surface. Step S1120 comprises applying force to the die to bond the die to the target, wherein during applying force at theeffecting surface during the bond operation the die-shaping element is deformed toward the support body.

[0167] Optional step S1130 comprises controlling the rate of propagation of the bond front throughout the entire bond operation. Optional step S1140 maintaining contact between an entire surface of the die and the effecting surface throughout the entire bond operation. Optional step S1150 comprises maintaining application of pressure or vacuum on a rearward surface of the die throughout the entire bond operation.

[0168] Although preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims and as described above.

[0169] The optional features set out herein may be used either individually or in combination with each other where appropriate and particularly in the combinations as set out in the accompanying claims. The optional features for each aspect or exemplary embodiment of the invention, as set out herein are also applicable to all other aspects or exemplary embodiments of the invention, where appropriate. In other words, the skilled person reading this specification should consider the optional features for each aspect or exemplary embodiment of the invention as interchangeable and combinable between different aspects and exemplary embodiments.LIST OF REFERENCES

[0170] 10 Bond tool

[0171] 12 Deformable element

[0172] 20 Die

[0173] 30 Target

[0174] 100 Bond tool

[0175] 100’ Bond tool (prior art)

[0176] 102 Tool movement direction

[0177] 110 Support body

[0178] 110’ Support body (prior art)

[0179] 112 Frontward surface of supply body

[0180] 114 Recess

[0181] 120 Die-shaping element

[0182] 120’ Die-shaping element (prior art)

[0183] 124 Rearward surface of die-shaping element 122 Frontward surface of die-shaping element 126 Joints

[0184] 127 Elastomer part

[0185] 128 Metal part

[0186] 130 Effecting surface

[0187] 140 Interface region

[0188] 150 Fluid flow arrangement

[0189] 152 Interface region control arrangement 160 Vacuum arrangement

[0190] 160’ Vacuum arrangement (prior art)

[0191] 200 Die

[0192] 200’ Die (prior art)

[0193] 210 Bond initiation region

[0194] 300 Target

[0195] 400 Force distribution

[0196] 900 Bond head

[0197] 1000 Die bonder

Claims

32CLAIMS1. Bond tool for bonding a die to a target, the bond tool comprising:a die-shaping element, the die-shaping element comprising an effecting surface, wherein the effecting surface is configured to:contact the die; andapply a force to the die during a bond operation in which the die is bonded to the target;a support body configured to support the die-shaping element; andan interface region formed between a frontward portion of the support body or a portion of a frontward surface of the support body and a rearward portion of the die-shaping element or a portion of a rearward surface of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

2. Bond tool according to claim 1, wherein the die-shaping element is elastically deformable.

3. Bond tool according to claim 1 or 2, wherein a frontward surface of the die-shaping element provides the effecting surface.

4. Bond tool according to any preceding claim, wherein the effecting surface is configured to shape the die to provide a bond initiation region of the die.

5. Bond tool according to any preceding claim, wherein the interface region is defined by a frontward surface of the support body and a rearward surface of the die-shaping element.

6. Bond tool according to claim 5, wherein the frontward surface of the support body comprises a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body and into the recess.

7. Bond tool according to either of claims 5 or 6, wherein the rearward surface of the dieshaping element comprises a recess, and wherein, during the bond operation, application of force at the effecting surface causes the die-shaping element to deform toward the support body.

338. Bond tool according to any preceding claim, wherein the support body and / or the dieshaping element comprises a fluid flow arrangement configured to allow fluid into or out of the interface region.

9. Bond tool according to claim 8, wherein the fluid flow arrangement is configured to cause and / or allow the surface topology of the effecting surface to be adapted.

10. Bond tool according to claim 8 or 9, wherein the interface region is provided by:a frontward portion of the support body comprising a compressible material; and / or a rearward portion of the die-shaping element comprising a compressible material, such that, during the bond operation, the die-shaping element deforms toward the support due to force causing compression of the compressible material.

11. Bond tool according to any claim directly or indirectly dependent on claim 6, or claim 10, wherein the shape of the recess and / or of the compressible material defines the distribution of force at the effecting surface during and / or at the end of the bond operation.

12. Bond tool according to claim 11, wherein the shape of the recess and / or of the compressible material provides a relative increase in force toward one or more outer areas of the effecting surface during the bond operation.

13. Bond tool according to any preceding claim, wherein the die-shaping element comprises one or more joints and / or one or more flexible regions, the joints and / or flexible regions configured to facilitate deformation of one or more areas of the die-shaping element during the bond operation.

14. Bond tool according to any preceding claim, wherein the effecting surface is configured to hold the die.

15. Bond tool according to any preceding claim, wherein the bond tool further comprises a vacuum arrangement configured to apply vacuum thereby to hold the die at the effecting surface by negative pressure.

16. Bond tool according to any preceding claim, wherein the form of the interface region is configured to change:in response to application of force at the effecting surface; and / orbefore or during the application of force at the effecting surface, under control of an interface region control arrangement.

17. Bond tool according to claim 16, when dependent directly or indirectly on claims 8 to 10, wherein the interface region control arrangement is configured to control the form of the interface region by application of pressure or vacuum to the fluid flow channel.

18. The bond tool according to any one of the preceding claims, wherein the die-shaping element comprises:an elastomer part, the elastomer part providing the effecting surface; or a metal part, the metal part providing the effecting surface; oran elastomer part and a metal part, the metal part provided on the elastomer part, the metal part providing the effecting surface.

19. Bond tool according to any one of the preceding claims, wherein the effecting surface comprises a texture provided thereon for reducing a level of adhesion between the die and the effecting surface.

20. Die-shaping element for a bond tool for bonding a die to a target, the die-shaping element configured to be supported by a support body, the die-shaping element comprising:an effecting surface, wherein the effecting surface is configured to:contact the die; andapply a force to the die during a bond operation in which the die is bonded to the target;wherein an interface region is defined between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region is configured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

21. Support body for a bond tool for bonding a die to a target, the support body configured to support a die-shaping element comprising an effecting surface, wherein the effecting surface is configured to:contact the die; andapply a force to the die during a bond operation in which the die is bonded to the target;wherein an interface region is defined between a frontward portion of the support body and a rearward portion of the die-shaping element, wherein the interface region isconfigured to allow the die-shaping element to deform toward the support body due to force on the die-shaping element during the bond operation.

22. Bond head comprising the bond tool, die-shaping element, or support body, according to any one of the preceding claims.

23. Die bonder comprising the bond tool, die-shaping element, support body, or bond head, according to any one of the preceding claims.

24. Die bonder according to claim 23, further comprising a metrology device configured to perform imaging thereby to determine one or more characteristics of the die when the die is held at the effecting surface.

25. Method of bonding a die to a target using a bond tool according to one of the claims 1 to 19 comprising the following steps:contacting the die with the effecting surface;applying a force to the die to bond the die to the target, wherein during applying the force at the effecting surface, the die-shaping element is deformed toward the support body.

26. The method according to claim 25, wherein controlling the rate of propagation of the bond front is continuously performed during bonding.

27. Method according to claim 25 or to claim 26, wherein maintaining contact between an entire surface of the die and the effecting surface is continuously performed during bonding.

28. Method according to any of the claims 25 to 27, wherein maintaining a substantially constant level of pressure or vacuum on a rearward surface of the die is continuously performed during bonding.

29. Method according to any of the claims 25 to 28, further comprising the step of applying or controlling a force to the die with a force distribution, which is homogenous across the die surface or increasing towards the edges of the die.

30. Bond tool, bond head, die-shaping element, support body, die bonder, or method, according to any one of the preceding claims, wherein the target is selected from the group comprising a die, a stack of dies, a package, a substrate, an interposer, a lead frame, a wafer, or any combination thereof.

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