Apparatus and method for removing surface oxides

Abstract

An apparatus and method for removing surface oxides includes an electron emitter device for emitting electrons for electron attachment, facilitating the removal of oxides from solder bumps and / or solder caps on pillars on the surface of a wafer passing through an oven or furnace. The electron emitter device may include one or more modules having electron emitting members having a plurality of protrusions positioned between different housing elements such that the protrusions extend through openings defined at interfaces between the housing elements. The modules of the device can be modularly and releasably attached to module support members for repair or replacement using fasteners or other mechanisms (e.g., via bolts or screws), allowing maintenance to occur more quickly and efficiently, reducing equipment downtime and improving operational flexibility.

Description

Technical Field

[0001] This invention relates to apparatus and methods for removing surface oxides from material surfaces. Some embodiments can be used to remove oxides from solder bumps and solder cap pillars to allow solder bump reflow, thereby providing a smooth surface for wafers or other materials. Background Technology

[0002] Electronic device packages may include wafer bump wafers and corresponding integrated circuit packages that allow interconnection. In wafer bumps, solder bumps or solder caps on electrodeposited copper pillars can be formed above a silicon wafer on which integrated circuits can be built. The wafer can then undergo solder reflow at a temperature above the solder melting point to transform the bumps or solder caps into a ball or spherical shape. The formed bumps can be used for electrical connections, mechanical connections, and mounting connections.

[0003] It is generally desirable to remove oxides from the formed bumps and prevent additional oxidation on the bump surface. Often, oxides are removed by coating the bumped wafer with an additive material and then exposing the coated wafer to a nitrogen atmosphere. However, this method can lead to wafer contamination via residues and / or volatiles that may form. Furthermore, the use of additive materials may require relatively frequent cleaning of the reflow oven or drying oven, which can result in significant operational downtime and higher maintenance costs for removing such contaminants from the wafer processing equipment.

[0004] The use of additive materials can also affect the quality of the formed wafer. For example, in reflow processes that may occur after oxide removal with additive materials, the additives can affect the molten solder and create voids within the formed bumps, which may degrade the bump performance.

[0005] Fluxless soldering has been performed to avoid the use of flux materials to remove oxides from the formed bumps. Fluxless techniques often use a formic acid vapor environment. This can complicate the process because formic acid vapor requires a sealed vacuum system. Furthermore, formic acid vapor is not completely residue-free, and therefore can lead to wafer contamination.

[0006] Some types of fluxless welding applications involve, for example, using lasers to ablate or heat metal oxides to their vaporization temperature. This process is typically performed in an inert or reducing atmosphere to prevent re-oxidation by released contaminants. However, the melting or boiling points of the oxide and the base metal can be similar, and melting or evaporating the base metal may be undesirable. Therefore, such laser processes are often difficult to implement. Lasers are typically expensive and inefficient to operate, and require direct line of sight to the oxide layer, further limiting the usefulness of laser technology for most welding applications.

[0007] Examples of additive-free techniques for welding and / or oxide removal can be found in U.S. Patents 9,053,894, 9,006,975, 8,617,352, 8,593,778, 8,454,850, 8,119,016, and 7,897,029, as well as U.S. Patent Application Publication No. 2009 / 0008426. Summary of the Invention

[0008] As mentioned above, soldering can result in the formation of surfaces that require smoothing or processing to remove metal oxides. For example, such oxide removal can be performed to help remove metal oxides from solder bumps and / or solder caps on pillars on the wafer surface. This process can be performed on one or more silicon wafers with multiple bumps and / or pillars on their outer surfaces and surface oxides thereon.

[0009] One type of additive-free metal oxide removal technique can involve the dissociation of hydrogen molecules and the attachment of electrons to hydrogen anions via low-energy electron emission. When the hydrogen anions return to their stable state, the metal oxide is transformed into an oxide-free metal surface. The release of energy allows the metal oxide to be reduced to form a metal.

[0010] Electron emission modules can provide an electronic attachment (EA) method for flux-free soldering, which can occur under ambient pressure and normal soldering temperatures. Examples can be utilized in a non-flammable furnace atmosphere comprising a mixture of nitrogen and hydrogen, containing less than or equal to 5% by volume of hydrogen and greater than or equal to 95% by volume of nitrogen. In some embodiments, the atmosphere may consist only of nitrogen and hydrogen, wherein the atmosphere contains 0 to 5% by volume of hydrogen and the remainder of the atmosphere is nitrogen (e.g., 95 to 100% by volume). The electron emission module can be positioned to emit electrons toward a wafer passing through a chamber or oven having this type of atmosphere, such that the electrons remove oxygen from the oxide-containing surface and react with hydrogen in the atmosphere, causing the oxide to be removed from the wafer, and forming a non-toxic material (e.g., water vapor) in the atmosphere that may not hinder the ongoing oxide removal process.

[0011] Electron emission modules can be difficult to manufacture. Often, an electron emission module comprises its own anode and cathode. By applying positive and negative pulsed direct current (DC) voltages in the range of 2 kV to 3 kV, electrons can be independently emitted from the module toward a wafer with solder bumps and / or solder cap pillars (e.g., solder cap copper pillars) from which oxides may need to be removed. When the solder bumps and solder cap pillars on the wafer are isolated from ground and cannot discharge charge, the emission module can collect free electrons accumulated on the solder bumps and solder cap pillars on the wafer surface and still emit electrons via pulsed voltages.

[0012] Embodiments of electron emission modules may be included on a common mounting substrate for positioning or mounting in an oven, such that an array comprising multiple different modules may be included within or on the mounting substrate. This type of design can provide improved flexibility in the manufacture, repair, or replacement of the modules. In some embodiments, the formed array may be considered an electron emission device.

[0013] For example, in cases where one or more electron emission tips of a module need repair or replacement, the operator can more easily access the array to quickly remove or repair the affected component. This can help reduce downtime and maintenance costs, while also providing improved operational flexibility.

[0014] In some embodiments, the electron emission module may include a housing body comprising a first housing element and a second housing element. An electron emission member having a plurality of electron emission protrusions may be positioned within a cavity of these housing elements and positioned between the housing elements such that the distal ends of the protrusions extend from an opening defined between the first and second housing elements. One or more fasteners (e.g., screws and / or bolts) may be used to engage or attach the first and second housing elements together to position the electron emission member between the elements such that the body of the member is enclosed by the element, and the distal ends of the protrusions of the electron emission member extend beyond the housing element and beyond the outer surface of the housing element.

[0015] The substrate to which the electron emission module can be attached may include multiple components. The module support component may include a pre-selected configuration of openings and wiring channels defined therein for facilitating wiring to the module, such that DC current can be pulsed to the electron emission component of the module attached to the module support component. In some embodiments, a second mounting component may be attached to the module support component to facilitate the mounting of an array of electron emission modules. In other embodiments, the module support component may also facilitate the mounting and / or positioning of an array of electron emission modules attached to the module support component.

[0016] In some embodiments, an array of electron emission modules may be included in an electron emitter device for positioning and configuration for mounting to the wall or top of an oven. The oven may include a conveyor or transport mechanism configured to support one or more wafers for soldering and / or undergoing oxide removal, and to move one or more wafers through different zones of the oven at a preselected speed. In some embodiments, the conveyor mechanism may include, for example, rollers that can move to transport wafers through the oven.

[0017] In some embodiments, the oven may include a loading area, at least one preheating area, at least one electronic attachment area, a reflow area, at least one cooling area, and an unloading area, in which wafers can be loaded onto a transport mechanism for transport through the oven, and in which wafers processed at the unloading area can be output from the oven. The wafers may undergo soldering prior to electronic attachment, or may pass through the oven to remove oxides only. The electronic attachment process may occur by treating the surface of the wafer to remove oxides by pulses of positive and negative voltages (e.g., DC voltage) to the electron emission components of an electron emission device module to output electrons to the outer surface of the wafer. During the electronic attachment process, the oven atmosphere may include nitrogen and hydrogen as discussed above (e.g., a gas mixture comprising 95 to 100 vol% nitrogen and 0 to 5 vol% hydrogen). After the wafers are output from the oven, they may be included in a package or otherwise utilized.

[0018] In a first aspect, an electron emitter device is provided for an apparatus for removing oxides from solder bumps and / or solder caps on pillars of a wafer surface. The electron emitter device may include an electron emitter module having a first housing element, an electron emitter member having a base and a plurality of protrusions extending from the base, and a second housing element releasably attached to the first housing element to form a housing, such that the base of the electron emitter member is within a cavity of the housing and the protrusions extend through spaced openings defined in the housing. The housing may be sized and configured for attachment to an electron emitter module support member.

[0019] Several embodiments may be provided such that multiple electron emission modules may be included on or attached to an electron emission module support member, such that multiple electron emission modules are included on the same electron emission module support member. The electron emission module support member may be shaped and configured to define the positions of different electron emission modules thereon, such that different modules can be positioned on the electron emission module support member in a predefined configuration.

[0020] In a second aspect, the opening in the housing may be defined at the interface between a first housing element and a second housing element, wherein the first housing element abuts the second housing element at the interface. In other embodiments, the opening may be defined in the first housing element and / or the second housing element of the housing.

[0021] In a third aspect, the first housing element may have a conductive member, and the second housing element may also have a conductive member, such that the opening of the housing is positioned between the conductive member of the first housing element and the conductive member of the second housing element. In some embodiments, the conductive member of the first housing element comprises a metal strip or a metal bar, and the conductive member of the second housing element comprises a metal strip or a metal bar.

[0022] In a fourth aspect, the electron transmitter device may include a plurality of fasteners extending between a first housing element and a second housing element to releasably attach the first housing element to the second housing element to form a housing. For example, bolts and / or screws may be used as fasteners.

[0023] In a fifth aspect, the electron transmitter device may include an electron transmitter module support member. The electron transmitter module support member may have multiple wiring openings and multiple wiring conduits. A first side of the electron transmitter module support member may face the electron transmitter module. A second side of the electron transmitter module support member may be opposite its first side.

[0024] In a sixth aspect, the electron transmitter device may further include an oven mounting member attached to a second side of the electron transmitter module support member, wherein the second side of the electron transmitter module support member is opposite to a first side of the electron transmitter module support member. The oven mounting member facilitates mounting the electron transmitter device to an oven or furnace (e.g., a wall or top surface of the oven within a cavity). In some embodiments, the oven mounting member may include, for example, a plate or other type of mounting member.

[0025] In the seventh aspect, the electron emitting component is composed of metal or conductive material, and the protrusions are integrated with the base, making the electron emitting component a single unit. For example, the electron emitting component can be formed from a metal body, on which protrusions are formed by machining the metal.

[0026] In the eighth aspect, the electron transmitter device may include multiple electron transmitter modules. For example, the electron transmitter module of the first aspect may be considered a first electron transmitter module, and the electron transmitter device may further include a second electron transmitter module. The second electron transmitter module may have a structure similar to that of the first electron transmitter module. For example, the second electron transmitter module may have a first housing element of the second electron transmitter module; an electron transmitter member of the second electron transmitter module, wherein the electron transmitter member of the second electron transmitter module has a base and a plurality of protrusions extending from the base; and a second housing element of the second electron transmitter module, the second housing element being releasably attached to the first housing element of the second electron transmitter module to form a housing of the second electron transmitter module, such that the base of the electron transmitter member of the second electron transmitter module is located within a cavity of the housing of the second electron transmitter module, and the protrusions of the electron transmitter member of the second electron transmitter module extend through an opening defined in the housing of the second electron transmitter module. The housing of the second electron transmitter module may be sized and configured for attachment to an electron transmitter module support member.

[0027] In some embodiments, the electron transmitter device may further include a third electron transmitter module. The third electron transmitter module may be structured similarly to the first and second electron transmitter modules. For example, the third electron transmitter module may have a first housing element; an electron transmitter member having a base and a plurality of protrusions extending from the base; and a second housing element releasably attached to the first housing element to form a housing of the third electron transmitter module, such that the base of the electron transmitter member is within a cavity of the housing, and the protrusions of the electron transmitter member extend through openings defined in the housing. The housing of the third electron transmitter module may be sized and configured for attachment to an electron transmitter module support member.

[0028] In some embodiments, the electron transmitter device may further include at least one fourth electron transmitter module. Each fourth electron transmitter module may be structured similarly to the first, second, and third electron transmitter modules. For example, each fourth electron transmitter module may have a first housing element of the fourth electron transmitter module; an electron transmitter member of the fourth electron transmitter module, wherein the electron transmitter member of the fourth electron transmitter module has a base and a plurality of protrusions extending from the base; and a second housing element of the fourth electron transmitter module, the second housing element being releasably attached to the first housing element of the fourth electron transmitter module to form a housing of the fourth electron transmitter module, such that the base of the electron transmitter member of the fourth electron transmitter module is within a cavity of the housing of the fourth electron transmitter module, and the protrusions of the electron transmitter member of the fourth electron transmitter module extend through openings defined in the housing of the fourth electron transmitter module. The housing of the fourth electron transmitter module may be sized and configured for attachment to an electron transmitter module support member.

[0029] In some embodiments, the electron transmitter device may include an electron transmitter module support member having a plurality of wiring openings and a plurality of wiring conduits. A first side of the electron transmitter module support member may face at least one of a first, second, third, and / or fourth electron transmitter module. The first electron transmitter module may be positioned adjacent to or on at least one of a corresponding set of wiring openings and wiring conduits, the second electron transmitter module may be positioned adjacent to or on at least one of a corresponding set of wiring openings and wiring conduits, the third electron transmitter module may be positioned adjacent to or on at least one of a corresponding set of wiring openings and wiring conduits, and / or the fourth electron transmitter module may be positioned adjacent to or on at least one of a corresponding set of wiring openings and wiring conduits.

[0030] In the ninth aspect, the electron transmitter device of the first aspect may include one or more features of the second, third, fourth, fifth, sixth, seventh, and / or eighth aspects. Embodiments may also include other elements or features. Examples of other elements or features can be learned from the exemplary embodiments discussed herein.

[0031] In a tenth aspect, a method for removing surface oxides from at least one wafer is provided. Embodiments of this method may include providing an electron emitter device for positioning in an electron attachment region of an oven. The electron emitter device may be an embodiment of the electron emitter device discussed in the first, second, third, fourth, fifth, sixth, seventh, eighth, or ninth aspects above. For example, the electron emitter device may include an electron emitter module having a first housing element, an electron emitter member having a base and a plurality of protrusions extending from the base, and a second housing element releasably attached to the first housing element to form a housing, such that the base of the electron emitter member is within a cavity of the housing and the protrusions extend through an opening defined in the housing. The housing may be sized and configured for attachment to an electron emitter module support member.

[0032] The method may also include positioning an electron emitter device in an electron attachment region of an oven or furnace for emitting electrons to remove oxide from at least one surface of at least one wafer passing through the oven. Embodiments of the method may also include other steps or features.

[0033] In an eleventh aspect, the method of the tenth aspect may further include positioning an electron-emitting member within a cavity of a first housing element and forming a first electron-emitting module by attaching a second housing element to the first housing element, such that the electron-emitting member is within a housing formed between the first and second housing elements, and a protrusion of the electron-emitting member extends through an opening. In some embodiments, the opening may be defined at an interface between the first and second housing elements, where the first housing element abuts the second housing element. In other embodiments, the opening may be defined in either the first or second housing element. In still other embodiments, some openings may be defined in the first housing element and some openings may be defined in the second housing element.

[0034] In some embodiments, the openings and protrusions of the housing may be positioned between the conductive members of the first housing element and the conductive members of the second housing element. Each conductive member may be a metal strip or a strip of another type of conductive material.

[0035] In the twelfth aspect, the method may further include removing the electron emission module from the electron emission module support member and replacing the removed electron emission module with a new electron emission module.

[0036] In a thirteenth aspect, the method may include removing an electron emission module from an electron emission module support member and separating a first housing element from a second housing element to replace the electron emission element with a new electron emission element. The method may further include positioning the new electron emission element between the first and second housing elements and releasably attaching the first housing element to the second housing element via fasteners to form a housing, such that the base of the new electron emission element is enclosed within the first and second housing elements, and a protrusion extending from the base of the new electron emission element extends through an opening in the housing.

[0037] As discussed above, in some embodiments, the opening through which the protrusion of the new electron-emitting member extends can be defined at the interface between a first housing element and a second housing element, where the first housing element abuts the second housing element. In other embodiments, at least some openings can be defined at the interface, defined in the first housing element, and / or defined in the second housing element.

[0038] In the fourteenth aspect, the method may include positioning an electron emission module on an electron emission module support member such that the electron emission module is positioned adjacent to at least one of a plurality of wiring openings defined in the electron emission module support member and at least one of a plurality of wiring conduits defined in the electron emission module support member.

[0039] In some embodiments, the electron emission module may be a first electron emission module, and the electron transmitter provision device may further include positioning an additional electron emission module on an electron emission module support member. For example, the method may further include positioning a second electron emission module on the electron emission module support member such that the second electron emission module is spaced apart from the first electron emission module, and the second electron emission module is positioned adjacent to at least one of a plurality of wiring openings defined in the electron emission module support member and at least one of a plurality of wiring conduits defined in the electron emission module support member. As another example, the method may further include positioning a third electron emission module on the electron emission module support member such that the third electron emission module is spaced apart from the first electron emission module and / or spaced apart from the second electron emission module, and the third electron emission module is positioned adjacent to at least one of a plurality of wiring openings defined in the electron emission module support member and at least one of a plurality of wiring conduits defined in the electron emission module support member. As another example, the method may further include positioning a fourth electronic emission module on an electronic emission module support member such that the fourth electronic emission module is spaced apart from the first electronic emission module, the second electronic emission module, and / or the third electronic emission module, and the fourth electronic emission module is positioned adjacent to at least one of a plurality of wiring openings defined in the electronic emission module support member and at least one of a plurality of wiring conduits defined in the electronic emission module support member.

[0040] In the fifteenth aspect, the method of the tenth aspect may include one or more features of the eleventh, twelfth, thirteenth, and / or fourteenth aspects. Embodiments may also include other elements or features. Examples of other elements or features may be learned from the exemplary embodiments discussed herein.

[0041] In a sixteenth aspect, a system is provided for removing oxides from solder bumps and / or solder caps on pillars of a wafer surface. The system may include an oven having at least one electron attachment region and an electron emission module positioned in the electron attachment region of the oven. The electron emission module may have a first housing element, an electron emission member having a base and a plurality of protrusions extending from the base, and a second housing element releasably attached to the first housing element to form a housing, such that the base of the electron emission member is within a cavity of the housing and the protrusions extend through openings defined in the housing. The housing may be attached to an electron emission module support member. The electron emission module support member may be attachable to a wall or top surface of the oven, so that electrons can be emitted from the protrusions and guided to the surface of a wafer positioned on a transport mechanism of the oven.

[0042] In some embodiments, the electron emission module may be an electron emission module of an electron transmitter device. For example, the electron transmitter device may be an embodiment of the electron transmitter device of the first aspect, second aspect, third aspect, fourth aspect, fifth aspect, sixth aspect, seventh aspect, eighth aspect, or ninth aspect.

[0043] Embodiments of the system may also utilize other elements or features. For example, the system may include program control elements, sensors, or other mechanisms or features.

[0044] In some embodiments, the oven of the system can be considered a furnace. In some embodiments, the oven may also include other areas upstream and / or downstream of the electronic attachment area.

[0045] It should be understood that embodiments of the methods for removing surface oxides, the equipment for removing surface oxides, and the electron emitter device can utilize various structural elements and / or programmable control elements. Embodiments may utilize sensors (e.g., pressure sensors, temperature sensors, flow rate sensors, concentration sensors, etc.), controllers, valves, piping, and / or other programmable control elements. For example, some embodiments may utilize automated programmable control systems and / or distributed control systems (DCS). Various piping configurations and programmable control systems can be used to meet a specific set of design criteria.

[0046] Further details, objectives, and advantages of the apparatus for removing surface oxides, the method for removing surface oxides, the electron emitter device, and the methods of manufacture and use thereof will become apparent in the following description of some of its exemplary embodiments. Attached Figure Description

[0047] Exemplary embodiments of methods for removing surface oxides, apparatus for removing surface oxides, electron emitter devices, and methods of manufacturing and using thereof are shown in the accompanying drawings. It should be understood that the same element symbols used in the drawings may identify the same components.

[0048] Figure 1 (Figure 1) (also known as) Figure 1 (FIG. 1) is a schematic illustration of an apparatus 1 for wafer processing, which may include an apparatus 4 for removing surface oxides, and the apparatus may include a plurality of electron emitter devices 5.

[0049] Figure 2 (also known as) Figure 2 ( ) is a schematic diagram of an exemplary embodiment of the electron transmitter device 5.

[0050] Figure 3 (also known as) Figure 3( ) is a schematic diagram of an exemplary embodiment of the electron transmitter module of the electron transmitter device 5.

[0051] Figure 4 (also known as) Figure 4 ( ) is a top view of the electron transmitter module of electron transmitter device 5.

[0052] Figure 5 (also known as) Figure 5 ) is along Figure 4 The cross-sectional view of the electron transmitter module of electron transmitter device 5 is taken by line EE.

[0053] Figure 6 (also known as) Figure 6 ( ) is a schematic diagram of the transmitter component of the electronic transmitter module of the electronic transmitter device 5.

[0054] Figure 7 (also known as) Figure 7 ( ) is a top view of the intermediate support member 8 of the electron transmitter device 5.

[0055] Figure 8 (also known as) Figure 8 ( ) is a bottom view of the intermediate support member 8 of the electron transmitter device 5.

[0056] Figure 9 (also known as) Figure 9 ( ) is a bottom view of the mounting support 7 of the electron transmitter device 5.

[0057] Figure 10 (also known as) Figure 10 This is a flowchart illustrating a method for removing surface oxides. An embodiment of the device 1 for removing surface oxides and / or at least one electron emitter device 5 can be used in an embodiment of this method.

[0058] The component symbols used in the diagram include:

[0059] 1. Equipment used for wafer processing;

[0060] 3. Drying oven;

[0061] 4. Equipment for removing surface oxides;

[0062] 5. Electron transmitter device;

[0063] 5a First electron transmitter device;

[0064] 5b Second electron transmitter device;

[0065] 6. Conveying mechanism;

[0066] 7. Oven mounting components;

[0067] The mounting component of the 7a oven faces the mounting structure side;

[0068] 8. Electron emission module mounting components;

[0069] The first side of the mounting component for the 8a electron emission module;

[0070] The second side of the 8b electron emission module mounting component;

[0071] 8c wiring conduit;

[0072] 8o wiring opening;

[0073] 9. Electron emission modules;

[0074] 10. Casing;

[0075] 10a First housing element;

[0076] 10b Second housing element;

[0077] 10f fasteners;

[0078] 10i interface;

[0079] Conductive components of a 10m housing element;

[0080] 10° opening;

[0081] 11 Electron emission components;

[0082] The base of the 11b electron emission component;

[0083] The protrusion of the 11p electron emission component;

[0084] S1 First step;

[0085] S2, second step;

[0086] S3, third step;

[0087] S4, fourth step;

[0088] S5, step five;

[0089] W wafers; and

[0090] WM wafer movement direction. Detailed Implementation

[0092] refer to Figures 1 to 10The apparatus 1 for wafer processing may include an oven 3, which may include a housing for enclosing the atmosphere around one or more zones of the oven 3. The oven 3 may also be considered a furnace. The zones of the oven 3 may include a first zone, which may be considered a "load zone" or loading zone, in which one or more wafers W may be positioned on a transport mechanism 6 for movement through the oven 3 in the wafer movement direction WM. The zones of the oven may also include at least one preheating zone, at least one electronic attachment (EA) zone, at least one reflow zone, at least one cooling zone, and at least one off-loading zone or "off-load zone," in which the wafers W may be removed from the transport mechanism for further processing, manipulation, or use.

[0093] The wafer W can be a silicon wafer or another type of wafer. The wafer can be a silicon wafer on which one or more integrated circuits have been built. In some embodiments, the wafer can be a type of electronic device or can be configured for electronic device packaging.

[0094] The oven may include one or more preheating zones, such as a first preheating zone (preheating 1) and a second preheating zone (preheating 2). The EA zone may include a first EA zone (EA zone 1) and a second EA zone (EA zone 2). One or more cooling zones may include a first cooling zone (cooling zone 1) and a second cooling zone (cooling zone 2). These zones may be located within the oven such that the first preheating zone is between the second preheating zone and the loading zone. The first EA zone may be between the second EA zone and the second preheating zone. A reflux zone may be between the first cooling zone and the second EA zone, and the second cooling zone may be between the first cooling zone and the unloading zone.

[0095] The oven can be positioned and configured to receive a feed of oven gas for providing an atmosphere within the oven. In some embodiments, the oven gas can be a mixture of nitrogen and hydrogen. For example, hydrogen can be present at a concentration below the flammability level of hydrogen, and nitrogen can be the remainder of the oven gas mixture. In some embodiments, the oven gas can contain 95 to 100% by volume nitrogen and 0 to 5% by volume hydrogen.

[0096] The conveying mechanism 6, which can be positioned in the oven, may include conveyor rollers for transporting wafers W through the oven 3.

[0097] The oven can be configured such that the wafer is preheated to a desired preselected electron attachment temperature in one or more preheating zones, then passes through one or more EA attachment zones to emit electrons to the outer surface of the wafer W to remove oxide from the surface, then passes through a reflow zone before passing through a cooling zone, and finally exits the oven's unloading zone. The cooling zone can be a lower temperature area of ​​the oven or a zone at ambient temperature to help cool the wafer after it has passed through the reflow zone.

[0098] The preselected electronic attachment temperature can be lower than the melting point of the solder alloy for the solder bumps or solder caps on the pillars. For example, the preselected electronic attachment temperature can be in the range of 100°C to 320°C, 115°C to 300°C, or 180°C to 250°C. The temperature of the preheating zone can be achieved by heating the wafer to the preselected electronic attachment temperature at a preselected ramp temperature rate, in conjunction with transporting the wafer through the oven via a conveyor at a preselected transport speed. The preselected ramp temperature can be determined based on the melting point of the solder alloy used for the solder bumps and solder caps on the pillars (e.g., copper pillars, etc.). In some embodiments, the preselected ramp temperature rate can be between 40°C per hour and 60°C per hour. Other embodiments may utilize other ramp temperature rates.

[0099] Each EA attachment area may include at least one electron emitter device 5, which includes an emitter array. The emitter array of each electron emitter device may include one or more electron emission modules 9. For example, a first EA attachment area may include at least one first electron emitter device 5a mounted to the wall or top surface of the oven for guiding electrons to the outer surface of the wafer below the electron emitter device 5 via at least one electron emission member 11 of one or more electron emission modules 9 of the device. A second EA attachment area may also include at least one second electron emitter device 5b mounted to the wall or top surface of the oven for guiding electrons to the outer surface of the wafer below the electron emitter device 5 via at least one electron emission member 11 of one or more electron emission modules 9 of the device.

[0100] Electron emitter devices 5 can be positioned in an oven to emit electrons toward the surface of the wafer to remove oxides from the wafer surface and / or bumps formed on the wafer surface via soldering. Each electron emitter device 5 can be electrically coupled to positive and negative DC voltage sources to pulse the voltage to the electron emission module 9 of the electron emitter device 5, so that electrons can be guided to the outer surface of the wafer passing below or beside the electron emitter device 5, allowing hydrogen to dissociate and add electrons to form hydrogen anions in the oven atmosphere, and react with the oxides on the solder bumps and solder caps on the surface of the wafer W to remove oxides from the wafer surface. The voltage fed to the electron emission module 9 of the electron emitter device 5 can be pulsed, allowing electrons to be guided to the outer surface to promote the reaction between hydrogen and oxides to form water vapor and remove oxides from the wafer surface. In addition, pulses can be executed to remove excess electrons from the wafer W to avoid charge accumulation in the wafer W.

[0101] If possible Figures 2 to 9 It is best understood that each of the electron transmitter devices 5 may include a plurality of electron transmitter modules 9, which may be connected to an electron transmitter module support member 8. In some embodiments, the electron transmitter module support member 8 may be connected to an oven mounting member 7 such that the electron transmitter module support member 8 is positioned between the oven mounting member 7 and the electron transmitter modules 9. The oven mounting member 7 may have a mounting structure facing side 7a, which may be configured to facilitate mounting of the electron transmitter device 5 to a wall or top surface of the oven 3. Fasteners and / or other attachment mechanisms may be used to attach the oven mounting member 7 to the top surface or wall of the oven. Fasteners and / or other attachment mechanisms may be used to attach the oven mounting member to the electron transmitter module support member 8. Fasteners and / or other attachment mechanisms may also be used to attach the electron transmitter modules 9 to the electron transmitter module support member 8.

[0102] Each electron emission module 9 may have an electron emission member 11 positioned between different housing elements (e.g., a first housing element 10a and a second housing element 10b, etc.) to enclose a large portion of the electron emission member 11 within the formed housing 10 of the electron emission module 9. The housing elements may include at least two housing elements, such as a first housing element 10a and a second housing element 10b. Each housing element 10a may define a chamber and have an opening defined therein, such that when the first housing element 10a and the second housing element 10b are attached together, they define an opening 10o in the formed housing at the outer surface of the housing adjacent to the interface 10i between the first housing element 10a and the second housing element 10b. The first housing element 10 and the second housing element 10b can be fastened together by fasteners after the electron emission member 11 is positioned between the housing elements, such that the protrusion 11p can extend out of the opening 10o of the housing, such that the base 11b of the electron emission member 11 is in the cavity of the housing 10 formed through the opening 10o through which the protrusion 11p of the electron emission member extends.

[0103] The distal tip of the protrusion 11p can be positioned outside the outer surface of the housing 10 away from the housing 10 via the protrusion 11p extending through and out of the opening 10o.

[0104] Each of the first housing element 10a and the second housing element 10b may have a cavity that partially defines the housing housing holding the base 11b of the electron emission member 11. For assembling the electron emission modules, the electron emission member 11 may be positioned within the cavity of the first housing element 10a such that a protrusion 11p extends out of a portion of the opening 10o defined by the first housing element 10a. The second housing element 10b may be positioned adjacent to the first housing element to form an opening 10o at the interface 10i between the first housing element 10a and the second housing element 10b, thereby enclosing the base of the electron emission member 11 within the cavity of the formed housing 10. Fasteners may then be applied through the first and second housing elements to attach the elements together to complete the housing 10, with the distal end of the protrusion 11p positioned outside the cavity and the opening 10o.

[0105] Each housing element may also have a conductive member 10m, which is positioned to extend adjacent to the opening 10o such that the opening 10o is between the interface 10i and the conductive material strip. Each conductive member 10m may be a metal strip (e.g., a copper strip, an aluminum strip, etc.) or another type of elongated member made of conductive material.

[0106] Each housing element may include a lower opening or connector for receiving wiring to receive voltage and / or current transmission to the electron emission component 11. The lower opening may be on a side of the housing element opposite to the portion having the opening 10o, through which a protrusion 11p extends. The lower opening of the housing element may be defined to mate with lower openings of other housing elements, such that the formed housing 10 may have a wiring connection receiving hole defined therein, which may face the electron emission module support member 8 and be aligned with the respective wiring connection openings 8o defined in the electron emission module support member 8.

[0107] The electron emission module support member 8 may be a metallic member or a member made of another type of material (e.g., a polymer material, etc.), which may have an opening 8o defined therein for receiving wiring. A first side of the electron emission module support member 8 may be configured to face the electron emission module 9 and may include a wiring conduit 8c defined therein to extend between different openings 8o defined in the electron emission module support member 8. The wiring conduit 8c may be a groove defined in the first side 8a of the electron emission module support member 8 to extend between different openings 8o to facilitate wiring for connecting wiring to different electron emission members 11 of different electron emission modules 9.

[0108] In some embodiments, for example, the wiring conduit 8c may be a bend or elbow-shaped groove defined between adjacent openings 8o. The openings 8o and the wiring conduit 8c may be defined on a first side of the electron emission module support member 8 to facilitate the positioning of wiring and / or the wiring along the electron emission module support member 8 for electrically coupling electron emission members 11 within different housings 10 of different electron emission modules to a voltage source that can emit electrons via pulses.

[0109] The electron emission module support member 8 may have a second side 8b opposite to its first side, which may face the oven mounting member 7. This second side may have an opening 8o through which the first side 8a and the second side 8b of the electron emission module support member 8 can pass, but may not have any wiring conduits 8c defined thereon. In yet another embodiment, it is conceivable that wiring conduits 8c may also be defined on the second side 8b of the electron emission module support member 8.

[0110] Fastener holes may also be defined in the electron emission module support member 8 adjacent to the opening 8o to facilitate the positioning and fastening of the housing elements 10a of each of the electron emission modules 9 to the first side 8a of the electron emission module support member 8. The opening 8o and the wiring channel 8c may be defined on the first side 8a of the electron emission module support member 8 to facilitate the positioning of the housing 10 of the electron emission module 9 and the attachment of the electron emission module housing 10 to the first side 8a of the electron emission module support member 8.

[0111] In some embodiments, fasteners for mounting the housing 10 of the electron emission module 9 to the electron emission module support member 8 may pass through the electron emission module support member 8 and also engage or contact the oven mounting member 7. In other configurations, fasteners may extend from the second side 8b of the electron emission module support member 8 to the lower portion of the housing elements 10a, 10b of each housing 10 for attaching the housing 10 of the electron emission module 9 to the electron emission module support member 8.

[0112] The electron emitting component 11 can be a monolithic structure. For example, the electron emitting component 11 can be formed of metal and can be drilled or cut to form protrusions 11p, such that the base 11b is integral with the protrusions 11p, the distal ends of the protrusions having a preselected thickness or preselected profile, and the entire electron emitting component 11 is a monolithic structure. In some embodiments, the electron emitting component 11 can be made of stainless steel, aluminum, copper, or other types of metals or alloys. In yet another embodiment, the electron emitting component can be formed of another type of conductive material.

[0113] In some embodiments, each of the protrusions 11p may be defined to have multiple emission surfaces due to the angle of its distal end (e.g., the tip of the emitter protrusion). In other embodiments, each protrusion may have a single emission surface.

[0114] The use of fasteners and electron emission module support member 8 and / or oven mounting member 7 can facilitate the simple installation of electron emission module 9 for use. Additionally, housing elements for housing 10 may include interlocking profiles, mating profiles, and / or one or more other attachment mechanisms to facilitate the positioning and attachment of housing elements for forming housing 10 and closing the base 11b of electron emission member 11, thus the protrusion 11p extends through the opening 10o formed at the interface 10i of the housing element of housing 10. Examples of such mating or interlocking profiles may include corresponding tenon and groove profiles, corresponding dovetail joint profiles, or other types of mating or interlocking profiles.

[0115] In another embodiment, the opening 10o may be defined within one of the housing elements, rather than at the interface 10i of the housing element. In this embodiment, the opening 10o may be defined to aid in positioning the electron emitting member 11 for forming the housing 10 and positioning the electron emitting member 11 in a desired location, for enclosing the base 11b of the electron emitting member 11 within the housing 10 during the formation of the housing 10, while the protrusion 11p extends through the opening 10o.

[0116] The embodiments can also be configured to allow repair or maintenance work to occur more quickly and efficiently. For example, in the event that some protrusions 11p of the electron emission component 11 are damaged or cease to function effectively, the module 9 can be easily accessed, removed from the electron emission module support member 8, and replaced with a new electron emission module 9. Furthermore (or alternatively), the housing 10 can be structured such that the removal of the fasteners 10f allows for the removal of the electron emission component 11 and the positioning of a new electron emission component 11 to replace the damaged one. The housing elements can then be fastened together again, and the repaired module can be remounted to the electron emission module support member 8 using fasteners. This type of functionality and module arrangement allows for easier repair and / or maintenance of the module array, while also making the manufacture of the electron emitter device 5 easier and simpler. The embodiments can allow repair work to occur more quickly and allow for the availability and storage of inventory for maintenance purposes at a lower cost and in a more readily accessible manner. This can help significantly reduce downtime associated with maintenance and repair work and also helps provide enhanced operational flexibility.

[0117] Embodiments of the electron emitter device 5 and the electron emitter module 9 can be used in embodiments of methods for removing surface oxides. Embodiments of such methods may also include providing the electron emitter device 5 and / or repairing and replacing at least one electron emitter module 9 of the electron emitter device 5.

[0118] Examples of embodiments of the method can be found in Figure 10As seen in the diagram. For example, in the first step S1, the emitting member 11 can be positioned within the cavity of the first housing element 10a for forming the first electron emission module 9 of the electron emitter device 5. In the second step S2, the first electron emission module 9 can then be formed by attaching the second housing element 10b to the first housing element 10a, such that the base 11b of the electron emission member 11 is positioned within the cavities of the housing elements 10a and 10b and between the first housing element 10a and the second housing element 10b, so that the protrusion 11p of the electron emission member 11 can extend from an opening 10o (e.g., a hole) defined between the first housing element 10a and the second housing element 10b. Such openings 10o can, for example, be defined at the interface 10i of the first housing element 10a adjacent to the second housing element 10b.

[0119] In some embodiments, an elongated conductive member 10m may be positioned on the first housing element 10a and the second housing element 10b adjacent to the opening 10o, such that the opening 10o and the protrusion 11p are located between the conductive member 10m positioned on the first housing element 10a and the second housing element 10b forming the housing 10. The conductive member 10m may be positioned on the housing elements 10a, 10b before the housing elements are attached together to form the housing and / or before the electron emission member is positioned in the cavity of at least one of the housing elements, for positioning and attaching the housing elements to form the housing 10 and the electron emission module 9.

[0120] In the third step S3, the first electron emission module 9 can be positioned on the substrate. For example, the formed first electron emission module 9 can be positioned on the first side 8a of the electron emission module support member 8. The wiring conduit 8c and wiring opening 8o of the first side 8a of the electron emission module support member 8 can face the first electron emission module 9, and the positioning of the first electron emission module 9 can be guided by the position of the wiring opening 8o and the wiring conduit 8c (e.g., a wiring groove that can extend between the wiring openings 8o).

[0121] In the fourth step S4, the other electron emission modules 9 can be formed in the same manner as the first electron emission module 9, and can be positioned on the first side 8a of the electron emission module support member 8 with a pre-configured pattern, which can be defined by the wiring conduits 8c and wiring openings 8o of the first side 8a of the electron emission module support member 8. Each electron emission module 9 can be positioned such that a separate set of wiring openings 8o and wiring conduits 8c face the electron emission module 9, and these wiring openings 8o and wiring conduits 8c can guide the electron emission module 9 to be positioned on the first side 8a of the electron emission module support member 8.

[0122] Each of the electron emission modules 9 can be fastened to the first side 8a of the electron emission module support member 8 via fasteners (e.g., bolts or screws) and / or other connecting mechanisms (e.g., interlocking profiles, mating profiles, etc.) to facilitate a releasable connection between the electron emission module 9 and the first side 8a of the electron emission module support member 8. Before or after connecting the module 9 to the first side 8a of the electron emission module support member 8, wiring can be coupled to the electron emission member 11 of the module 9 via a wiring opening 8o and a wiring conduit 8c.

[0123] In the fifth step S5, the substrate on which the electron emission module 9 is mounted can be mounted onto a holder element for positioning the electron emission device 5 in a region of an oven for processing one or more wafers W passing through the oven to remove oxide from the surface of the wafers W via electronic attachment. This electronic attachment process can be provided via a pulsed voltage applied to the electron emission member 11 of the electron emission module 9 of the electron emission device 5.

[0124] For example, the second side 8b of the electron emitter module support member 8 can be connected to the oven mounting member 7. The oven mounting member can then be fastened to the top or wall mounting structure, top surface, or wall of the oven for mounting and positioning the electron emitter device 9 within the oven 3 in the EA zone of the oven. Fasteners and / or other connectors can be used to facilitate this connection and mounting.

[0125] The installed electron emitter device 5 can then be used in the operation of removing oxides from wafer W as described above. For example, each electron emitter device 5 can be electrically coupled to positive and negative DC voltage sources, such that voltage can be pulsed to the electron emission member 11 of the electron emission module 9 of the electron emitter device 5, and electrons can be emitted from protrusions 11p and guided to the outer surface of the wafer passing under or beside the electron emitter device 5. As a result, hydrogen can be dissociated by free electrons attached to the oven atmosphere to form hydrogen anions, which can react with oxides on the solder bumps and solder caps on the pillar surfaces of wafer W to remove oxides from the surface. The voltage fed to the electron emission member 11 of the electron emitter device 5 can be pulsed, such that electrons can be guided to the outer surface to promote the reaction between hydrogen anions formed by gas and oxides to form water vapor, and remove oxides from the solder bumps and / or solder caps on the pillars of the wafer surface. In addition, pulses can be executed to remove excess electrons from wafer W to avoid charge accumulation in wafer W.

[0126] In cases where one or more of the electron emission modules 9 need repair or replacement, such electron emission module 9 can be removed from the first side 8a of the electron emission module support member 8 and replaced with a new electron emission module 9. Alternatively, the electron emission module 9 can be removed from the first side 8a of the electron emission module support member 8, the housing elements 10a and 10b can be separated from each other, and the electron emission member 11 can be replaced with a new electron emission member 11. Then, the first housing element 10a and the second housing element 10b can be re-fastened together, so that the protrusion 11p of the new electron emission member 11 passes through the opening 10o, and the formed electron emission module 9 can be attached to the first side 8a of the electron emission module support member 8, and the new electron emission member 11 can be wired to a voltage source for subsequent use.

[0127] This type of modular structure facilitates improved repair and replacement operations, making such work faster and easier to perform. Furthermore, it helps reduce downtime associated with such maintenance or repair work.

[0128] It should also be understood that embodiments of the device 1 and method can be modified to meet specific criteria or specifications for the device or method. For example, embodiments can be configured for use in conjunction with automated program control schemes and / or distributed control schemes, and the size or type of the device can also be modified to meet a specific set of design criteria. As another example, the number of electron emission modules 9, the shape of the housing 10, and / or the shape of the electron emission member 11 can be any of a number of suitable sizes and shapes that meet pre-selected design criteria. As another example, the material composition of the different components can be any of a number of suitable options that meet pre-selected design criteria. As yet another example, the type of wiring, the configuration of the wiring opening 8o and the wiring conduit 8c, the shape and profile of the housing 10, the electron emission module support member 8, and / or the oven mounting member 7 can be any of a number of suitable shapes and sizes that meet design criteria or oven dimensions. It should also be understood that the oven 3 can be considered a furnace.

[0129] The specific features described herein (either alone or as part of an embodiment) may be combined with other separately described features or parts of other embodiments. Thus, elements and actions of the various embodiments described herein may be combined to provide further embodiments. Therefore, although certain exemplary embodiments of methods, apparatuses, systems, and methods of making and using the same have been shown and described above, it will be clearly understood that the invention is not limited thereto, but may be embodied and practiced differently in other ways within the scope of the following claims.

Claims

1. An electron emitter device for oxide removal, the electron emitter device comprising: An electron emission module, the electron emission module comprising: First housing element; An electron-emitting component, comprising a base and a plurality of protrusions extending from the base; and A second housing element is releasably attached to the first housing element to form a housing, such that the base of the electron emission member is within the cavity of the housing and the plurality of protrusions extend through an opening defined in the housing; The housing is sized and configured for attachment to the electron emission module support member.

2. The electron transmitter device of claim 1, wherein the opening of the housing is defined at an interface between the first housing element and the second housing element, the first housing element being adjacent to the second housing element at the interface.

3. The electron transmitter device of claim 1, wherein the first housing element includes a conductive member, and the second housing element includes a conductive member, such that the opening of the housing is positioned between the conductive member of the first housing element and the conductive member of the second housing element.

4. The electronic transmitter device according to claim 1, comprising: A plurality of fasteners extending between the first housing element and the second housing element to releasably attach the first housing element to the second housing element to form the housing.

5. The electronic transmitter device according to claim 1, comprising: The electron emission module support component, wherein: The electron emission module support component includes multiple wiring openings and multiple wiring conduits, and The first side of the electron emission module support member faces the electron emission module.

6. The electronic transmitter device according to claim 5, comprising: An oven mounting member is attached to the second side of the electron emission module support member, the second side of the electron emission module support member being opposite to the first side of the electron emission module support member.

7. The electron transmitter device according to claim 1, wherein the electron transmitting component is composed of metal or conductive material, and the plurality of protrusions are integral with the base, such that the electron transmitting component is a single unit.

8. The electron transmitter device according to claim 1, wherein the electron transmitting module is a first electron transmitting module, and the electron transmitter device further comprises: A second electron emission module, comprising: The first housing element of the second electron emission module; The second electron emission module's electron emission component, the electron emission component of the second electron emission module including a base and a plurality of protrusions extending from the base; and A second housing element of the second electron emission module, which is releasably attached to the first housing element of the second electron emission module to form a housing of the second electron emission module, such that the base of the electron emission member of the second electron emission module is within the cavity of the housing of the second electron emission module and the plurality of protrusions of the electron emission member of the second electron emission module extend through an opening defined in the housing of the second electron emission module; The housing of the second electron emission module is sized and configured for attachment to the electron emission module support member.

9. The electron transmitter device according to claim 8, further comprising: A third electron emission module, comprising: The first housing element of the third electron emission module; The electron emission component of the third electron emission module includes a base and a plurality of protrusions extending from the base; and The second housing element of the third electron emission module is releasably attached to the first housing element of the third electron emission module to form the housing of the third electron emission module, such that the base of the electron emission member of the third electron emission module is located within the cavity of the housing of the third electron emission module and the plurality of protrusions of the electron emission member of the third electron emission module extend through an opening defined in the housing of the third electron emission module. The housing of the third electron emission module is sized and configured for attachment to the electron emission module support member.

10. The electron transmitting device according to claim 9, further comprising: The electron emission module support component, wherein: The electron emission module support component includes multiple wiring openings and multiple wiring conduits. The first side of the electron emission module support member faces the first, second, and third electron emission modules. The first electron emission module is positioned adjacent to or on at least one of a corresponding set of the wiring openings and the wiring conduits. The second electron emission module is positioned adjacent to or on at least one of a corresponding set of the wiring openings and the wiring conduits, and The third electron emission module is positioned adjacent to or on at least one of the corresponding set of the wiring openings and the wiring conduits.

11. A method for removing surface oxides from at least one wafer, the method comprising: An electron transmitter device is provided for positioning in the electronic attachment area of ​​an oven, the electron transmitter device comprising: An electron emission module, the electron emission module comprising: First housing element; An electron-emitting component, comprising a base and a plurality of protrusions extending from the base; and A second housing element is releasably attached to the first housing element to form a housing, such that the base of the electron emission member is within the cavity of the housing and the plurality of protrusions extend through an opening defined in the housing; The housing is sized and configured for attachment to the electron emission module support member; and The electron emitter device is positioned in the electron attachment region of the oven for emitting electrons to remove oxides from at least one surface of at least one wafer passing through the oven.

12. The method of claim 11, wherein providing the electron transmitter device comprises: The electron emission component is positioned in the cavity of the first housing element and the first electron emission module is formed by attaching the second housing element to the first housing element, such that the electron emission component is within the housing formed between the first housing element and the second housing element and the plurality of protrusions of the electron emission component extend through the opening, the opening being defined at the interface between the first housing element and the second housing element, at which the first housing element is adjacent to the second housing element.

13. The method of claim 12, wherein the opening and the plurality of protrusions of the housing are positioned between the conductive member of the first housing element and the conductive member of the second housing element.

14. The method of claim 11, wherein the at least one surface is a solder bump on the at least one wafer and / or a solder cap on a pillar on the at least one wafer.

15. The method of claim 11, further comprising: Remove the electron emission module from the electron emission module support member and replace the removed electron emission module with another electron emission module.

16. The method of claim 11, further comprising: Remove the electron emission module from the electron emission module support member and separate the first housing element from the second housing element to replace the electron emission component with a new electron emission component; as well as The new electron emission member is positioned between the first housing element and the second housing element, and the first housing element is releasably attached to the second housing element via fasteners to form the housing, such that the base of the new electron emission member is enclosed within the first housing element and the second housing element, and a plurality of protrusions extending from the base of the new electron emission member extend through the opening of the housing.

17. The method of claim 16, wherein the protrusion of the new electron emitting member extends through the opening of the housing, which defines an interface between the first housing element and the second housing element, at which the first housing element is adjacent to the second housing element.

18. The method of claim 11, wherein providing the electron transmitter device comprises: The electron emission module is positioned on the electron emission module support member such that the electron emission module is positioned adjacent to at least one of the plurality of wiring openings defined in the electron emission module support member and at least one of the plurality of wiring conduits defined in the electron emission module support member.

19. The method of claim 18, wherein the electron emission module is a first electron emission module and the electron transmitter device further comprises: The second electron emission module is positioned on the electron emission module support member such that the second electron emission module is spaced apart from the first electron emission module, and the second electron emission module is positioned adjacent to at least one of the plurality of wiring openings defined in the electron emission module support member and at least one of the plurality of wiring conduits defined in the electron emission module support member.

20. A system for oxide removal, the system comprising: An oven, which includes at least one electronic attachment area; An electron emission module, positioned within the electron attachment area of ​​the oven, the electron emission module comprising: First housing element; An electron-emitting component, comprising a base and a plurality of protrusions extending from the base; and A second housing element is releasably attached to the first housing element to form a housing, such that the base of the electron emission member is within the cavity of the housing and the plurality of protrusions extend through an opening defined in the housing; The housing is attached to an electron emission module support member, and the electron emission module support member may be attached to the wall or top surface of the oven, such that electrons emitted from the plurality of protrusions are guided to the surface of the wafer positioned on the conveying mechanism of the oven.

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