Ovens and related methods for apparatuses such as die attach systems, flip chip bonding systems, and wafer clip attach systems

Abstract

An oven for assisting in forming a conductive contact associated with a workpiece. The oven includes: (a) a chamber defined at least in part by (i) an oven plate and (ii) a lid; (b) a material handling system for moving the workpiece through the oven in connection with a conductive contact forming process; and (c) at least one vacuum chamber located within the chamber. The oven provides a stepped temperature profile that includes a plurality of temperature zones along the oven plate.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 040,576, filed June 18, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to ovens and related methods for use in devices such as grain attachment systems, flip-chip bonding systems, and wafer clip attachment systems. Background Technology

[0004] In the electronics assembly industry (e.g., including die attaching, flip chip bonding, clip attaching, etc.), connections involving solder materials are frequently used. For example, in certain traditional die attach applications, soft solder interconnects can be used. In other examples, in certain clip attach applications, solder reflow interconnects can be used.

[0005] For applications of die attachment and chip clip attachment, ovens can be used in interconnect processes (e.g., in solder reflow processes).

[0006] Many factors need to be considered when designing such an oven. For example: the processing time of workpieces (e.g., per hour); temperature control of workpieces as they pass through the oven; availability of oven components (e.g., for maintenance, cleaning, etc.); and so on.

[0007] Therefore, there is a desire to provide improved ovens, as well as related equipment and processes, for use in the electronics assembly industry. Summary of the Invention

[0008] According to an exemplary embodiment of the present invention, an oven is provided for assisting in the forming of conductive contacts in relation to a workpiece. The oven includes: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving a workpiece through the oven in relation to a conductive contact forming process; and (c) at least one vacuum chamber located within the chamber. The oven provides a stepped temperature profile comprising a plurality of temperature zones along the oven plate.

[0009] According to another exemplary embodiment of the present invention, a grain attachment system is provided. The grain attachment system includes: a grain source including a plurality of grains; a support structure for supporting a workpiece; a placement system for transferring at least one of the plurality of grains from the grain source to the workpiece; and an oven for assisting in the forming of conductive contacts associated with the workpiece after the at least one of the plurality of grains has been placed using the placement system. The oven includes: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with the conductive contact forming process; and (c) a vacuum chamber located within the chamber. The oven provides a stepped temperature profile that includes a plurality of temperature zones along the oven plate.

[0010] According to another exemplary embodiment of the present invention, a flip-chip bonding system is provided. The flip-chip bonding system includes: a grain source comprising a plurality of grains; a support structure for supporting a workpiece; a flip-chip placement system for transferring at least one of the plurality of grains from the grain source to the workpiece; and an oven for assisting in the forming of conductive contacts associated with the workpiece after the at least one of the plurality of grains has been placed using the flip-chip placement system. The oven includes: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with the conductive contact forming process; and (c) a vacuum chamber located within the chamber. The oven provides a stepped temperature profile comprising a plurality of temperature zones along the oven plate.

[0011] According to another exemplary embodiment of the present invention, a clip attachment system is provided. The clip attachment system includes: a clip source including a plurality of conductive clips; a support structure for supporting a workpiece; a clip placement system for placing at least one of the plurality of conductive clips onto the workpiece; and an oven for assisting in the forming of conductive contacts associated with the workpiece after the at least one of the plurality of conductive clips has been placed using the clip placement system. The oven includes: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with the conductive contact forming process; and (c) a vacuum chamber located within the chamber. The oven provides a stepped temperature profile that includes a plurality of temperature zones along the oven plate.

[0012] According to another exemplary embodiment of the present invention, a method for designing an oven for providing conductive contact forming is provided. The method includes the steps of: (a) determining a stepped temperature profile to be provided in a cavity of the oven, the cavity being defined at least partially by (i) an oven plate of the oven and (ii) a lid of the oven, the cavity including at least a vacuum chamber; and (b) providing design details for the oven such that the stepped temperature profile includes a plurality of temperature zones along the oven plate.

[0013] Any details of the oven described in this specification can be incorporated into methods for designing an oven for providing conductive contact forming. Non-limiting details of such an oven include: the oven being configured to provide substantially uniform temperature within each of a plurality of temperature zones; the oven plate being designed to define a plurality of recesses along the oven plate defining a plurality of temperature zones; the oven plate being designed to define a single recess among the plurality of recesses between each of the plurality of temperature zones along the oven plate; the oven plate being designed to define a subset of the plurality of recesses between each of the plurality of temperature zones along the oven plate; and the oven plate being designed such that at least one recess in the subset of the plurality of recesses is provided with an active cooling fluid.

[0014] The present invention further relates to the customization of stepped temperature profiles. Oven design involves many variables, such as: recess details; active cooling fluid details; heater operation (e.g., operation of a single heating element); and so on. For example, at least two heater elements (e.g., heaters, heating elements, etc.) can be provided for each of a plurality of temperature zones, wherein at least two heater elements are individually controllable. These variables can be optimized so that stepped temperature profiles can be customized for a given application to provide the desired stepped temperature profile. Attached Figure Description

[0015] The invention can be best understood by reading the following detailed description in conjunction with the accompanying drawings. It should be emphasized that, by convention, the various features in the drawings are not drawn to scale. Instead, for clarity, the dimensions of the various features have been arbitrarily enlarged or reduced. The drawings include the following figures:

[0016] Figure 1A This is a top block view of an oven according to an exemplary embodiment of the present invention;

[0017] Figure 1B yes Figure 1A A side view block diagram of the oven;

[0018] Figure 1C It includes Figure 1A An exemplary stepped temperature profile for multiple temperature zones of an oven;

[0019] Figure 1D yes Figure 1A Detailed view of the oven's recesses;

[0020] Figure 2A This is a top block view of another oven according to another exemplary embodiment of the present invention;

[0021] Figure 2B yes Figure 2A A side view block diagram of the oven;

[0022] Figure 2C yes Figure 2A Detailed view of the oven's recesses;

[0023] Figure 3A This is a top block view of yet another oven according to yet another exemplary embodiment of the present invention;

[0024] Figure 3B yes Figure 3A A side view block diagram of the oven;

[0025] Figure 3C yes Figure 3A Detailed view of the oven's recesses;

[0026] Figure 4A This is a top block view of yet another oven according to yet another exemplary embodiment of the present invention;

[0027] Figure 4B yes Figure 4A Side view of the oven;

[0028] Figure 4C yes Figure 4A Detailed view of the oven's recesses;

[0029] Figure 5A This is a top block view of yet another oven according to yet another exemplary embodiment of the present invention;

[0030] Figure 5B yes Figure 5A A side view block diagram of the oven;

[0031] Figure 5C yes Figure 5A Detailed view of the oven's recesses;

[0032] Figures 6A-6H yes Figure 1A A series of top and side block views of an oven are provided to illustrate a method of operating the oven according to an exemplary embodiment of the present invention.

[0033] Figures 7A-7D yes Figure 1AA series of top and side block views of an oven are provided to illustrate another method of operating the oven according to another exemplary embodiment of the invention.

[0034] Figure 8 This is a block diagram illustrating a grain attachment system according to an exemplary embodiment of the present invention;

[0035] Figure 9 This is a block diagram illustrating a flip-chip bonding system according to an exemplary embodiment of the present invention;

[0036] Figure 10 This is a block diagram illustrating a clip attachment system according to an exemplary embodiment of the present invention;

[0037] Figure 11 This is a block diagram illustrating another clip attachment system according to an exemplary embodiment of the present invention; and

[0038] Figure 12 This is a block diagram illustrating another clip attachment system according to an exemplary embodiment of the present invention. Detailed Implementation

[0039] This invention relates to an oven for assisting in the forming process of conductive contacts in workpieces. Such an oven can be used in many types of applications. For example, the conductive contact forming process can be associated with die attachment systems, flip-chip bonding systems, and wafer clamp attachment systems (which may include die attachment systems, flip-chip bonding systems, etc.).

[0040] The conductive contact forming process may include at least one of, for example, a sintering coupling process and a welding coupling process (e.g., a solder reflow coupling process). Other conductive contact forming processes may also be considered.

[0041] The workpiece undergoing this conductive contact forming process in the oven can vary widely. For example, the workpiece may include: (i) a plurality of dies; (ii) a substrate; and (iii) a plurality of conductive clips configured to provide conductive coupling between the dies and the substrate in the oven using a solder reflow process. In another example, the workpiece may include: (i) a plurality of dies; and (ii) a plurality of conductive clips configured to conductively couple to a corresponding die in the plurality of dies in the oven using a solder reflow process. In yet another example, the workpiece may include: (i) a die; (ii) a substrate; and (iii) at least one conductive clip configured to provide conductive coupling between the die and the substrate in the oven using a solder reflow process. In yet another example, the workpiece may include: (i) a die; and (ii) at least one conductive clip configured to conductively couple to the die in the oven using a solder reflow process. In yet another example, the workpiece may include a plurality of dies and a substrate, the dies being configured to be conductively coupled to the substrate in an oven using a solder reflow process. In yet another example, the workpiece may include a die and a substrate, the dies being configured to be conductively coupled to the substrate in an oven using a solder reflow process. Other types of workpieces (and conductive connections) may also be considered.

[0042] The present invention relates to an oven (and a method of operating thereof) that achieves desired control over a wide range of temperature profiles to optimally support solder reflow processes.

[0043] The present invention is particularly useful for applications that perform solder reflow under vacuum to improve solder layer integrity by significantly reducing void content. Although only a specific portion of the solder reflow process occurs under vacuum, the entire workpiece is typically under vacuum simultaneously. This can lead to an interruption of stepwise transport along a continuous temperature profile. To ensure that all portions of the leadframe encounter the same temperature profile along the rest of the oven, the profile preferably has a "stair-step" shape, with the temperature of the stepped regions ideally within ±5°C, a length equal to the width of at least one leadframe, and a sharp transition in the middle.

[0044] However, this is difficult to achieve on a continuous oven plate due to the lateral thermal conductivity of the oven plate, even when using steel with low thermal conductivity. An alternative design approach is to use the oven plate as the outer shell and generate each heating zone using separate heating blocks that are largely insulated from the oven plate. One disadvantage of this design is that the heating elements will be located inside the oven, with a sealed electrical feed for the power cord and thermal coupling lines. Furthermore, ovens with many cavities can be difficult to clean (e.g., removing process contaminants). Additionally, providing controlled airflow with limited gas consumption will be very challenging.

[0045] Exemplary embodiments of the present invention relate to an isolation concept that enables sufficient thermal isolation between regions to meet all temperature profile requirements for a wide range of region-to-region temperature differences (e.g., uniformity of ±5°C within each region) to support all known reflow temperature profiles.

[0046] The present invention enables: the realization of a vacuum recirculation zone / chamber; improved control of the temperature profile at any location on the workpiece or lead frame and of a single component from the lead frame to the lead frame; and / or improved heating efficiency by minimizing the number of index steps (i.e., by maximizing the contact time between the workpiece and the oven plate).

[0047] Any oven (or oven feature) described in this invention can be incorporated into a die attachment system, flip-chip bonding system, wafer clamp attachment system, or other device (e.g., placement device) within the scope of this invention. Any system according to the invention (e.g., die attachment system, flip-chip bonding system, wafer clamp attachment system, etc.) can include multiple placement systems (multiple placement systems of the same type, e.g., die pick-and-place system, flip-chip pick-and-place system, wafer clamp attachment system) (multiple placement systems of different types, e.g., die pick-and-place system and wafer clamp attachment system) in a single oven.

[0048] According to the present invention, a combined system including grain attachment and wafer clip attachment (and / or flip-chip bonding and wafer clip attachment) can be located in a single location or in different locations (e.g., the grain attachment system may be located in a different location than the wafer clip attachment system).

[0049] According to a specific exemplary embodiment of the invention, grooves (or other temperature-isolating features) can be provided along the oven plate of an oven. Specific embodiments of the invention involve having multiple temperature zones along the oven plate. For example, the purpose of the grooves (or other temperature-isolating features of the oven plate) may be to minimize heat flow from one side of the groove to the other (e.g., from one temperature zone to another). This purpose can be achieved by design options that control the thermal resistance provided by the grooves. For example, thermal resistance increases with a longer path of heat flow (e.g., a longer or deeper groove).

[0050] Now referencing oven 100 Figure 1A-1D . Figure 1A This is a top view of oven 100, with the lid 110 removed for simplicity. Figure 1B This is a side view of oven 100. Oven 100 includes an oven plate 102 and a lid 110. Oven 100 also includes a chamber 103 defined at least partially by the oven plate 102 and the lid 110. Chamber 103 surrounds a portion of oven 100 and is used, for example, to provide a controlled environment. Oven 100 also includes a material handling system 160 (e.g., a conveyor system, a beam motion system, a fixture-based system, etc.) for moving workpieces through oven 100 during conductive contact forming processes.

[0051] Oven 100 is configured to include a plurality of temperature zones 101a, 101b, 101c, 101d, etc., along oven plate 102. Oven plate 102 defines a plurality of recesses 104, each of which separates adjacent temperature zones. For example, temperature zone 101a and temperature zone 101b are separated by one of the recesses 104.

[0052] A plurality of heating blocks 116 are distributed below the oven plate 102 and between the recesses 104, such as Figure 1B As shown. The heating block 116 uses a heating rod 118 (i.e., a heating element) to heat and control the temperature of various temperature zones (e.g., temperature zones 101a, 101b, etc.). Figure 1B In the embodiment of the invention shown, two heating blocks 116 are provided below each of the plurality of temperature zones (excluding the temperature zones of vacuum chambers 112a and 112b). These heating blocks 116 can be controlled independently of each other or independently of other heating blocks 116 included in the oven 100.

[0053] The oven 100 also includes a region 106, which includes vacuum chambers 112a and 112b within the cavity 103. Region 106 includes a vacuum insert 102a disposed in the oven plate 102. That is, an additional element (i.e., the vacuum insert 102a) is provided in region 106 relative to the oven plate 102, which is continuously formed along the entire length of the oven 100. Therefore, the vacuum insert 102a provides a surface on which a workpiece can travel within region 106.

[0054] Oven 100 includes vacuum chambers 112a and 112b, both located in region 106. Vacuum chamber 112a includes a cover 108a that covers a portion of vacuum insert 102a. Vacuum chamber 112b includes a cover 108b that covers another portion of vacuum insert 102a. Region 106 includes heating blocks 116a and 116b (as opposed to heating block 116 included in the remainder of oven 100). More specifically, heating block 116a is provided to heat vacuum chamber 112a, and heating block 116b is provided to heat vacuum chamber 112b. Heating blocks 116a and 116b can be controlled independently of each other or independently of other heating blocks 116 included in oven 100.

[0055] According to a specific exemplary embodiment of the present invention, one or more vacuum chambers may be arranged along the oven plate (e.g., reference 1). Figure 1A-1D Various vacuum chambers are shown in 2A-2C, 3A-3C, 4A-4C, and 5A-5C. These vacuum chambers (e.g., vacuum chambers 112a and 112b) allow solder reflow under vacuum to improve solder layer integrity by significantly reducing void content. Although only specific portions of the reflow process occur under vacuum (e.g., in the various vacuum chambers described in this invention), it is desirable that the entire workpiece is simultaneously under vacuum.

[0056] According to a specific exemplary embodiment of the present invention, an oven 100 may provide a stepped temperature profile along an oven plate 102, comprising a plurality of temperature zones (e.g., temperature zones 101a, 101b, 101c, 101d, etc.). Such a stepped temperature profile may be provided by including a groove 104 in the oven plate 102 and by controlling a heater 116 (and heaters 116a, 116b).

[0057] The oven 100 also includes an inlet cooling block 114a and an outlet cooling block 114b (and a plurality of temperature zones 101a, 101b, 101c, 101d, etc., are disposed between the inlet cooling block 114a and the outlet cooling block 114b). Figure 1CAn exemplary stepped temperature profile is shown (each of a plurality of temperature zones has a controlled temperature; in a “stepped” configuration, each step has a substantially uniform temperature). According to the invention, a stepped temperature profile can be customized for a given application to provide a desired stepped temperature profile. That is, in a given application (e.g., in a specific solder reflow application), a specific temperature may be required over a specific period of time as the workpiece moves through the oven. Customization of the stepped temperature profile can be achieved, for example, by controlling the heat output of heater 116, adjusting the details of groove 104 (e.g., the arrangement of grooves, the number of grooves, the width of the grooves, details of the cooling fluid available in one or more grooves, etc.), and may include various other features as required by the application. Figure 1D A cross-sectional side view of the groove 104 is shown. (As shown) Figure 1D As shown, the groove 104 has a width W1, a height h1, and a lower wall thickness th1.

[0058] refer to Figure 2A-2C Apart from a single vacuum chamber 212a and a different recess configuration, the figures show an oven 200 similar to oven 100 (where identical elements have the same element symbol, or the element symbol begins with "2" instead of "1"). Oven 200 includes a lid (similar to...). Figure 1B The cover 110 shown is omitted from the figure for simplicity. Figure 2A The groove structure 204 is indicated (groove structure 204 in...) Figure 2C (As shown in detail in the cross-sectional view), it includes a subset of grooves (e.g., grooves 204a, 204b, and 204c). This subset of grooves 204a, 204b, and 204c is used to provide a stepped temperature profile between a plurality of temperature regions 201a, 201b, 201c, 201d, etc. (in a “stepped” configuration, a controlled temperature is present at each of the plurality of temperature regions). Groove 204a has a width W2a and a height h2, groove 204b has a width W2b and a height h2, and groove 204c has a width W2c and a height h2. Grooves 204a, 204b, and 204c are defined by a plurality of wall portions, including: an upper wall having a thickness th2a; a lower wall having a thickness th2b; and a side wall having a thickness th2c.

[0059] refer to Figures 3A-3C Apart from a different recessed construction and having a single vacuum chamber 312a (compared to oven 100), the figures show an oven 300 similar to oven 100 or oven 200 (where identical elements have the same element symbol, or the element symbol begins with "3" instead of "2" or "1"). Oven 300 includes a lid (similar to...). Figure 1BThe cover 110 shown is omitted from the figure for simplicity. Figure 3A The groove structure 304 is indicated (groove structure 304 in...) Figure 3C (As shown in detail in the cross-sectional view), it includes a subset of grooves (e.g., grooves 304a, 304b, 304c, 304d, 304e). This subset of grooves 304a, 304b, 304c, 304d, 304e is used to provide a stepped temperature profile between a plurality of temperature regions 301a, 301b, 301c, 301d, etc. (in the “stepped” configuration, there is a controlled temperature at each of the plurality of temperature regions). Groove 304a has a width W3a and a height h3; groove 304b has a width W3b and a height h3; the dimensions of grooves 304c, 304d, 304e are also configured in a similar manner. The grooves 304a, 304b, 304c, 304d, and 304e are defined by a plurality of wall portions, including: an upper wall having a thickness of th3a; a lower wall having a thickness of th3b; and a side wall having a thickness of th3c or th3d.

[0060] refer to Figures 4A-4C Except for having a different groove configuration including active cooling fluid (see groove structure 404) and having a single vacuum chamber 412a (compared to oven 100), these figures show an oven 400 similar to ovens 100, 200, or 300 (where the same elements have the same element symbols, or the element symbols begin with "4" instead of "3", "2", or "1"). Oven 400 includes a lid (similar to...) Figure 1B The cover 110 shown is omitted from the figure for simplicity. Figure 4A The groove structure 404 is indicated (groove structure 404 in...) Figure 4C(As shown in detail in the cross-sectional view), it includes a subset of grooves (e.g., grooves 404a, 404b, 404c). This subset of grooves 404a, 404b, 404c is used to provide a stepped temperature profile between a plurality of temperature regions 401a, 401b, 401c, 401d, etc. (in a “stepped” configuration, a controlled temperature is present at each of the plurality of temperature regions). Groove 404a has a width W4a and a height h4; groove 404b has a width W4b and a height h4; groove 404c has a width W4c and a height h4. Grooves 404a, 404b, 404c are defined by a plurality of walls, including: an upper wall having a thickness th4a; a lower wall having a thickness th4b; and sidewalls having thicknesses th4c or th4d. Groove 404a, closed using structure 490, is shown as having an active cooling fluid 480 provided therein. Active cooling fluid 480 (e.g., injected air, water or other cooling fluid) can be selectively (or constantly) supplied in recess 404a to provide a stepped temperature profile.

[0061] refer to Figures 5A-5C Except for having a different recess construction with active cooling fluid in the intermediate recess 504c (see recess structure 504) and a single vacuum chamber 512a (compared to oven 100), these figures show an oven 500 that is substantially similar to ovens 100, 200, 300, and 400 (where similar elements have the same element symbols, or element symbols begin with "5" instead of "4", "3", "2", or "1"). Oven 500 includes a lid (similar to...) Figure 1B The cover 110 shown is omitted from the figure for simplicity. Figure 5A The groove structure 504 is indicated (groove structure 504 in...) Figure 5C(As shown in detail in the cross-sectional view), it includes a subset of grooves (e.g., grooves 504a, 504b, 504c, 504d, 504e). This subset of grooves 504a, 504b, 504c, 504d, 504e is used to provide a stepped temperature profile between a plurality of temperature regions 501a, 501b, 501c, 501d, etc. (in the “stepped” configuration, there is a controlled temperature at each of the plurality of temperature regions). Groove 504a has a width W5a and a height h5; groove 504b has a width W5b and a height h5; groove 504c has a width W5c and a height h5; the dimensions of grooves 504d and 504e are also configured in a similar manner. Recesses 504a, 504b, 504c, 504d, and 504e are defined by a plurality of wall portions, including: an upper wall having a thickness th5a; a lower wall having a thickness th5b; and side walls having thicknesses th5c or th5d. Recess 504c, enclosed by structure 590, is shown having an active cooling fluid 580 provided therein. The active cooling fluid 580 (e.g., infused air, water, or other cooling fluid) can be selectively (or constantly) provided in recess 504c to provide a stepped temperature profile.

[0062] Figures 6A-6H This illustrates the process of forming conductive contacts in an oven 100 (according to the foregoing). Figure 1A-1D A plurality of workpieces 650 are processed within the scope of this process. As those skilled in the art will understand, Figures 6A-6H The details provided can be applied to other ovens, for example, Figure 2A-2C The oven shown is 200. Figures 3A-3C The oven shown is 300. Figures 4A-4C The oven shown is 400. Figures 5A-5C The oven 500 shown, and any other oven within the scope of this invention. Figures 6A-6B A first workpiece 650 with width W and length L is shown at an initial position above the inlet cooling block 114a. Figures 6C-6D A first workpiece 650 that has moved along oven plate 102 (e.g., using material handling system 160) to temperature zone 101a is shown, as well as a second workpiece 650 in its initial position. Figure 6E-6F It is shown that a plurality of workpieces 650 have been moved into oven 100, wherein the first workpiece 650 has moved along oven plate 102 before entering vacuum chamber 112a. Figure 6G-6H A plurality of workpieces 650 are shown, wherein a first workpiece 650 has been moved to a position inside a vacuum chamber 112b along an oven plate 102 (and a vacuum insert 102a), and a second workpiece 650 has been moved to a position inside a vacuum chamber 112a.

[0063] Figures 7A-7DThis illustrates the process of forming conductive contacts in an oven 100 (according to the foregoing). Figure 1A-1D A plurality of workpieces 750 are processed within the scope of this process. As those skilled in the art will understand, Figures 7A-7D The details provided can be applied to other ovens, for example, Figure 2A-2C The oven shown is 200. Figures 3A-3C The oven shown is 300. Figures 4A-4C The oven shown is 400. Figures 5A-5C The oven 500 shown, and any other oven within the scope of this invention. Figures 7A-7B The first group of workpieces 750 and the second group of workpieces 750 are shown (i.e., each group contains three workpieces), each workpiece having a corresponding width W' and length L'. Figures 7A-7B The image shows a second set of workpieces 750 at an initial position above the inlet cooling block 114a and a first set of workpieces 750 that have moved along the oven plate 102 (e.g., using the material handling system 160) to the temperature zone 101a. Figures 7C-7D The illustration shows multiple sets of workpieces 750 being moved into oven 100, wherein the first set of workpieces 750 has been moved along oven plate 102 (and vacuum insert 102a) to a position inside vacuum chamber 112b, while the second set of workpieces 750 has been moved to a position inside vacuum chamber 112a.

[0064] Therefore, various ovens have been described in conjunction with the scope of this invention. Figure 1A-1D 2A-2C, 3A-3C, 4A-4C, 5A-5C, 6A-6H, 7A-7D. Such ovens (e.g., oven 100, oven 200, oven 300, oven 400, oven 500, and any other oven within the scope of this invention) can be used in conjunction with various types of machines or systems. Examples of such machines / systems include die attachment systems, flip-chip bonding systems, wafer clip attachment systems, combinations thereof, etc. Figure 8-12 The workpiece input processor 824, oven 800, and workpiece output processor 834 are shown. Figure 8-12 In these example components, each is a similar component. Oven 800 could be, for example, oven 100 (from...). Figure 1A-1D ), Oven 200 (from Figure 2A-2C ), Oven 300 (from Figures 3A-3C ), Oven 400 (from Figures 4A-4C ), Oven 500 (from Figures 5A-5C (and any other oven within the scope of this invention.)

[0065] Figure 8A die attachment system 801 is shown. The die attachment system 801 includes: a workpiece input processor 824; a die bonder 820; an oven 800; and a workpiece output processor 834. The die bonder 820 includes: a die source 830 including a plurality of dies 832; a support structure 822 (including a material handling system) for supporting a workpiece 850; a dispensing unit 826 for dispensing attachment material 836 onto the workpiece 850; and a placement system 828 for transferring at least one of the plurality of dies 832 from the die source 830 to the workpiece 850. Furthermore, the die attachment system 801 includes a workpiece input processor 824 that provides the workpiece 850. The material handling system (sometimes referred to as a substrate conveyor or transporter) of the support structure 822 conveys the workpiece 850 through the die bonder 820. The dispensing unit 826 provides the attachment material 836 onto the workpiece 850. The die placement system 828 transfers die 832 from die source 830 to the area of ​​workpiece 850 where attachment material 836 is provided. The material handling system of support structure 822 transfers workpiece 850 to oven 800. Workpiece 850 is transferred through oven chamber 803. The completed workpiece 850 is removed from oven 800 by workpiece output processor 834.

[0066] Figure 9 A flip-chip bonding system 901 is shown. The flip-chip bonding system 901 is similar in some respects to... Figure 8 The die attachment system 801 (where identical components have the same component symbol, or the component symbol begins with "9" instead of "8"). However, the flip-chip bonding system 901 includes a flip-chip bonding machine 920 (compared to...). Figure 8 The die bonding machine 920 shown is an example of a flip-chip bonding machine. As shown, the flip-chip bonding machine 920 includes: a die source 930 (including a plurality of dies 932); a dispensing unit 926 (for dispensing material 936, such as solder material, onto a workpiece 850); a flip-chip placement system 928; and a flipper 938. The flipper 938 flips the dies 932 (or other semiconductor devices) to position conductive structures on the dies 932 for bonding to conductive structures on the workpiece 850.

[0067] Figure 10 A clip attachment system 1001 is shown. The clip attachment system 1001 is similar in some respects to... Figure 8 The die attachment system 801 (where identical components have the same component symbol, or the component symbol begins with "10" instead of "8"). However, the die clip attachment system 1001 includes a die clip bonding machine 1040 (compared to...). Figure 8The die bonding machine 820 shown is an example. The die-clamp bonding machine 1040 includes: a dispensing unit 1026 (for dispensing material 1036, such as solder material, onto workpiece 850); a die-clamp placement system 1042; and a die-clamp input source 1044 (e.g., a roller with a stamping unit, a bowl feeder, etc.). A material handling system (sometimes referred to as a substrate conveyor or transporter) of the support structure 1022 conveys workpiece 850 through the die-clamp bonding machine 1040. The dispensing unit 1026 provides material 1036 onto workpiece 850. The die-clamp placement system 1042 conveys die-clamp 1052 from the die-clamp input source 1044 to the area of ​​workpiece 850 where material 1036 is located. The material handling system of the support structure 1022 conveys workpiece 850 to an oven 800 for bonding. Workpiece 850 is conveyed through an oven chamber 803 for bonding. The completed workpiece 850 is removed from the oven 800 via the base plate output processor 834.

[0068] Figure 11 The clip attachment system 1101 is shown. The clip attachment system 1101 is essentially similar to a bonding system. Figure 10 The described clip attachment system 1001 (where identical components have the same component symbol, or the component symbol begins with "11" instead of "8" or "10"). However, the clip attachment system 1101 also includes previously coupled... Figure 8 The described grain bonding machine 820. Figure 11The diagram illustrates a plurality of workpieces 850 provided at different locations via a die-attachment process (primarily by die-attachment machine 820), a wafer-clamp attachment process (primarily by wafer-clamp attachment machine 1040), and a conductive structure forming process (provided by oven 800). At a first location to the left of die-attachment machine 820, workpiece 850 is shown in two positions where attachment material 836 has been placed on workpiece 850 by dispensing unit 826. At a second location to the right of die-attachment machine 820, workpiece 850 is shown in four different locations where attachment material 836 has been placed on workpiece 850, and two dies 832 have been placed on workpiece 850 in two locations by die placement system 828 (wherein, dies 832 are obtained from die source 830). At a third location to the left of wafer-clamp attachment machine 1040, workpiece 850 is shown in four locations where attachment material 836 has been placed on workpiece 850, and four dies 832 have been placed on workpiece 850. At the third position, workpiece 850 is shown with material 1036 placed in two positions by the dispensing unit 1026. At the fourth position to the right of the die clamping machine 1040, workpiece 850 is shown with attachment material 836 placed in four positions on workpiece 850, four dies 832 placed on workpiece 850, material 1036 placed in four positions on workpiece 850, and two die clamps 1052 (from die clamping input source 1044) placed on material 1036 in two positions on workpiece 850 using die clamping placement system 1042. At the fifth position, workpiece 850 is shown before entering oven 800 to form conductive structural contacts. At the sixth position, workpiece 850 is shown inside oven chamber 803 for forming conductive structural contacts.

[0069] Figure 12 The clip attachment system 1201 is shown. The clip attachment system 1201 is essentially similar to a bonding system. Figure 10 The described clip attachment system 1001 (where identical components have the same component symbol, or the component symbol begins with "12" instead of "8", "9", or "10"). However, the clip attachment system 1201 also includes previously combined... Figure 9 The described flip-chip bonding machine 920. Figure 12The diagram illustrates a plurality of workpieces 850 provided at different locations via a flip-chip bonding process (primarily by flip-chip bonding machine 920), a wafer clamp attachment process (primarily by wafer clamp bonding machine 1040), and a conductive structure forming process (provided by oven 800). At a first location to the left of flip-chip bonding machine 920, workpiece 850 is shown with material 936 placed on it at two locations via dispensing unit 926. At a second location to the right of flip-chip bonding machine 920, workpiece 850 is shown with material 936 placed at four different locations, and two dies 932 have been arranged on the workpiece 850 at two locations (on the material 936) via flip-chip placement system 928 (where the dies 932 are obtained from die source 930). At a third location to the left of wafer clamp bonding machine 1040, workpiece 850 is shown with material 936 placed at four locations, and four dies 932 have been placed on it. At the third position, workpiece 850 shows material 1036 placed in two positions by the distribution unit 1026. At the fourth position to the right of the wafer clamping machine 1040, workpiece 850 is shown with material 1036 placed in four positions, four dies 932 placed on workpiece 850, material 1036 placed in four positions on workpiece 850, and two wafer clamps 1052 (from wafer clamping input source 1044) placed on material 1036 in two positions on workpiece 850 using wafer clamping placement system 1042. At the fifth position, workpiece 850 is shown before entering oven 800 to form conductive structural contacts. At the sixth position, workpiece 850 is shown inside oven chamber 803 for forming conductive structural contacts.

[0070] Although Figure 12 Excluding die bonding machines, such as Figure 8 and Figure 11 The die bonding machine 820 shown should be understood to be capable of being integrated into the wafer clamp attachment system 1201 (e.g., upstream or downstream of the flip-chip bonding machine 920). Therefore, within the scope of this invention, any combination of die bonding machines, flip-chip bonding machines, and wafer clamp bonding machines can be integrated into a single wafer clamp attachment system (or other system). More specifically, multiple die types can be integrated into a single workpiece. Thus, a wafer clamp attachment system (or die bonding system, or flip-chip bonding system, or other systems within the scope of this invention) can include multiple bonding machines of different types as needed for a given application.

[0071] Although the embodiments of the invention described herein relate to ovens comprising oven plates formed from a single sheet of material, the invention is not limited thereto. The various oven plates described herein may be formed from a single sheet of material or from multiple sheets of material. For example, if the oven plate is formed from multiple sheets of material, each of the multiple sheets of material may be separated from adjacent materials in the multiple sheets by air gaps. In another example, if the oven plate is formed from multiple sheets of material, a low thermal conductivity material may be provided between each of the multiple sheets of material.

[0072] Although the embodiments of the invention described herein relate to specific groove configurations (e.g., having a single groove or multiple grooves) (e.g., grooves with specific widths, heights, wall thicknesses, etc.) (e.g., with active cooling and without active cooling), such configurations are exemplary in nature, and the invention is not limited thereto. Any details of such grooves can be varied within the scope of the invention. For example, an oven plate may have some groove structures including a single groove (e.g., Figure 1A-1D The described groove 104), and some other groove structures that may have multiple grooves (e.g., a subset of grooves, e.g., Figures 4A-4C The described groove structure 404 can be selectively positioned along the length of the oven plate as needed. In another example, the width, height, and wall thickness of the groove structure can vary; that is, in a single groove structure, the width, height, and wall thickness of each groove can be different from each other. In yet another example, grooves with active cooling (and without active cooling) can be arranged as needed in a single groove structure (with multiple grooves), and / or arranged along the length of the oven plate as needed. Therefore, it is obvious that the details of the grooves (and groove structures) shown in this invention are essentially exemplary.

[0073] In a specific detailed example, an oven plate within the scope of this invention (and applicable to any oven described herein) may include: a grooved structure having multiple grooves at each end of the oven plate (e.g., grooved structure 404 or 504, or any other grooved structure having multiple grooves); and a single groove (e.g., Figure 1A-1D The groove 104 described is formed along the length of the oven plate, but is located between the groove structures of a plurality of grooves located at each end of the oven plate.

[0074] Although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made to the details within the equivalent scope and field of the claims and without departing from the invention.

Claims

1. An oven for assisting in the forming of conductive contacts related to a workpiece, the oven comprising: A chamber, the chamber being defined at least in part by (i) an oven plate and (ii) a cover; A material handling system for moving the workpiece through an oven associated with a conductive contact forming process; and At least one vacuum chamber is located within the cavity. The oven provides a stepped temperature profile, which includes multiple temperature zones along the oven plate. The oven plate defines a plurality of grooves, and the plurality of grooves define a plurality of temperature zones along the oven plate.

2. The oven as claimed in claim 1, wherein, The workpiece includes: (i) a plurality of grains; (ii) a substrate; and (iii) a plurality of conductive clips configured to provide conductive coupling between the grains of the plurality of grains and the substrate in the oven using a solder reflow process.

3. The oven as described in claim 1, wherein, The workpiece includes: (i) a plurality of dies; and (ii) a plurality of conductive clips configured to be conductively coupled to corresponding dies in the plurality of dies in the oven using a solder reflow process.

4. The oven as claimed in claim 1, wherein, The workpiece includes: (i) a die; (ii) a substrate; and (iii) at least one conductive clip configured to provide conductive coupling between the die and the substrate in the oven using a solder reflow process.

5. The oven as claimed in claim 1, wherein, The workpiece includes: (i) a die; and (ii) at least one conductive clip configured to be conductively coupled to the die in the oven using a solder reflow process.

6. The oven as claimed in claim 1, wherein, The workpiece includes a plurality of dies and a substrate, the plurality of dies being configured to be conductively coupled to the substrate in the oven using a solder reflow process.

7. The oven as claimed in claim 1, wherein, The workpiece includes a die and a substrate, the die being configured to be electrically coupled to the substrate in the oven using a solder reflow process.

8. The oven as claimed in claim 1, wherein, The stepped temperature profile is configured to be customized for a given application to provide a desired stepped temperature profile.

9. The oven as claimed in claim 1, wherein, The oven is configured to provide substantially consistent temperatures within each of the plurality of temperature zones.

10. The oven as claimed in claim 1, wherein, One of the plurality of grooves is defined along the oven plate between each of the plurality of temperature zones.

11. The oven as claimed in claim 1, wherein, A subset of the plurality of grooves is defined along the oven plate between each of the plurality of temperature zones, and the subset includes more than one groove.

12. The oven as claimed in claim 11, wherein, At least one groove in this subset is provided with an active cooling fluid.

13. The oven as claimed in claim 12, wherein, At least one other recess in this subset does not contain the active cooling fluid.

14. The oven as claimed in claim 1, wherein, Each of the plurality of temperature zones is provided with at least two heater elements, which are individually controllable.

15. The oven as claimed in claim 1, wherein, The conductive contact forming process associated with the workpiece provided in the oven includes at least one of a sintering coupling process and a welding coupling process.

16. The oven as claimed in claim 1, wherein, The conductive contact forming process associated with the workpiece provided in the oven includes a solder reflow coupling process.

17. The oven as claimed in claim 1, wherein, The oven plate is formed from a single sheet of material.

18. The oven as claimed in claim 1, wherein, The oven plate is formed from multiple sheets of material.

19. A grain attachment system, comprising: A single grain source comprises multiple grains; A support structure used to support a workpiece; A placement system for transferring at least one of the plurality of grains from the grain source to the workpiece; and An oven for assisting in the forming of conductive contacts associated with a workpiece after at least one of the plurality of grains has been placed using a placement system, the oven comprising: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with a conductive contact forming process; and (c) at least one vacuum chamber located within the chamber, wherein the oven provides a stepped temperature profile including a plurality of temperature zones along the oven plate, wherein the oven plate defines a plurality of grooves defining the plurality of temperature zones along the oven plate.

20. A flip-chip bonding system, comprising: A single grain source comprises multiple grains; A support structure used to support a workpiece; A flip-chip placement system for transferring at least one of the plurality of grains from the grain source to the workpiece; and An oven for assisting in the forming of conductive contacts associated with a workpiece after at least one of the plurality of grains has been placed using a flip-chip placement system, the oven comprising: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with a conductive contact forming process; and (c) at least one vacuum chamber located within the chamber, wherein the oven provides a stepped temperature profile including a plurality of temperature zones along the oven plate, wherein the oven plate defines a plurality of grooves defining the plurality of temperature zones along the oven plate.

21. A clip attachment system, comprising: A single clip-on source comprises a plurality of conductive clips; A support structure used to support a workpiece; A single-piece clamping system for placing at least one of the plurality of conductive sheet clamps onto the workpiece; as well as An oven for assisting in the forming of conductive contacts associated with a workpiece after at least one of a plurality of conductive clips has been placed using a clip placement system, the oven comprising: (a) a chamber defined at least partially by (i) an oven plate and (ii) a cover; (b) a material handling system for moving the workpiece through the oven associated with a conductive contact forming process; and (c) at least one vacuum chamber located within the chamber, wherein the oven provides a stepped temperature profile including a plurality of temperature zones along the oven plate, wherein the oven plate defines a plurality of grooves defining the plurality of temperature zones along the oven plate.

22. The clip attachment system of claim 21, further comprising: A grain source comprising a plurality of grains; and a placement system for transferring at least one of the plurality of grains from the grain source to the workpiece.

23. The clip attachment system of claim 21, further comprising: A grain source, comprising a plurality of grains; and a flip-chip placement system for transferring at least one of the plurality of grains from the grain source to the workpiece.

24. A method for designing an oven for providing conductive contact forming, the method comprising the steps of: (a) Determine a stepped temperature profile to be provided in a cavity of the oven, the cavity being defined at least in part by (i) an oven plate of the oven and (ii) a lid of the oven, the cavity including at least a vacuum chamber; as well as (b) Providing design details for the oven such that the stepped temperature profile includes a plurality of temperature zones along the oven plate, wherein step (b) includes designing the oven plate to define a plurality of grooves that define the plurality of temperature zones along the oven plate.

25. The method of claim 24, wherein, The oven is configured to provide substantially consistent temperatures within each of the plurality of temperature zones.

26. The method of claim 24, wherein, Step (b) includes designing the oven plate to define a single groove among the plurality of grooves between each of the plurality of temperature zones along the oven plate.

27. The method of claim 24, wherein, Step (b) includes designing the oven plate to define a subset of the plurality of grooves between each of the plurality of temperature zones along the oven plate.

28. The method of claim 27, wherein, Step (b) includes designing the oven plate such that at least one groove in the subset of the plurality of grooves is provided with an active cooling fluid.

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