Bonding tool and method for high accuracy chip-to-chip bonding
09685187 ยท 2017-06-20
Assignee
Inventors
Cpc classification
H01L2224/83193
ELECTRICITY
H01L2924/00012
ELECTRICITY
H01L2224/75251
ELECTRICITY
H01L2224/291
ELECTRICITY
H01L24/75
ELECTRICITY
H01L2224/75705
ELECTRICITY
B32B37/14
PERFORMING OPERATIONS; TRANSPORTING
B32B38/0012
PERFORMING OPERATIONS; TRANSPORTING
H01L2224/29026
ELECTRICITY
B32B2310/14
PERFORMING OPERATIONS; TRANSPORTING
H01L2924/01322
ELECTRICITY
H01L2224/83805
ELECTRICITY
H01L2224/83192
ELECTRICITY
H01L2924/00012
ELECTRICITY
H01L2924/01322
ELECTRICITY
H01L2224/75704
ELECTRICITY
H01L2224/75744
ELECTRICITY
H01L2224/75704
ELECTRICITY
B32B38/0008
PERFORMING OPERATIONS; TRANSPORTING
H01L2224/75744
ELECTRICITY
H01L2224/75705
ELECTRICITY
H01L2224/75745
ELECTRICITY
H01L2224/83191
ELECTRICITY
H01L2224/75252
ELECTRICITY
H01L2224/291
ELECTRICITY
B32B38/10
PERFORMING OPERATIONS; TRANSPORTING
H01L2224/75745
ELECTRICITY
G11B5/84
PHYSICS
H01L2224/29026
ELECTRICITY
International classification
B25J15/06
PERFORMING OPERATIONS; TRANSPORTING
H01L23/52
ELECTRICITY
B32B38/10
PERFORMING OPERATIONS; TRANSPORTING
B32B37/14
PERFORMING OPERATIONS; TRANSPORTING
G11B5/84
PHYSICS
B32B38/00
PERFORMING OPERATIONS; TRANSPORTING
H01L23/48
ELECTRICITY
Abstract
A chip-to-chip eutectic bonding system includes a stage with a top surface, a bottom surface, and a plurality of vacuum apertures extending therebetween and a carrier with a top surface, the top surface including one or more smooth surface portions and one or more rough surface portions, wherein at least one smooth carrier surface portion laterally aligns to at least one vacuum aperture, and at least one of the stage's rough surface portions frictionally couples to at least one of the carrier's rough surface portions when the carrier top surface couples to and opposes the stage bottom surface.
Claims
1. A bonding tool for alignment comprising: a stage and a carrier; wherein: the stage comprises a stage top surface, a stage bottom surface, and a plurality of vacuum apertures extending therebetween, wherein the stage top surface comprises one or more rough stage surface portions having an average roughness of between 50 nm and 150 nm; the carrier comprises a carrier bottom surface, wherein the carrier bottom surface comprises one or more smooth carrier surface portions having an average roughness of less than 50 nm and one or more rough carrier surface portions having an average roughness of between 50 nm and 150 nm; at least one smooth carrier surface portion of the one or more smooth carrier surface portions having an average roughness of less than 50 nm laterally aligns to at least one vacuum aperture of the plurality of vacuum apertures when the carrier bottom surface couples to and opposes the stage top surface; and at least one rough carrier surface portion of the one or more rough carrier surface portions having an average roughness of between 50 nm and 150 nm frictionally couples to the at least one rough stage surface portion having an average roughness of between 50 nm and 150 nm such that frictional force counteracts lateral movement of the carrier relative to the stage.
2. The bonding tool of claim 1, wherein the carrier is a chip carrier or a slider carrier.
3. The bonding tool of claim 1, further comprising a heater positioned to project heat on the stage.
4. The bonding tool of claim 1, wherein any rough carrier surface portion having an average roughness of between 50 nm and 150 nm laterally aligns to any rough stage surface portion having an average roughness of between 50 nm and 150 nm when the carrier top surface couples to the stage bottom surface.
5. The bonding tool of claim 4, wherein any smooth carrier surface portion having an average roughness of less than 50 nm forms a disk shape pattern surrounded by any rough carrier surface portion having an average roughness of between 50 nm and 150 nm.
6. The bonding tool of claim 4, wherein any smooth carrier surface portion having an average roughness of less than 50 nm forms a diamond shape pattern surrounded by any rough carrier surface portion having an average roughness of between 50 nm and 150 nm.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Various embodiments are illustrated by way of example, and not limitation, in the figures of the accompanying drawings in which:
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20) The figures are not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be understood that the invention can be practiced with modification and alteration, and that the disclosed technology be limited only by the claims and the equivalents thereof.
DETAILED DESCRIPTION
(21) In the following description, numerous specific details are set forth to provide a thorough understanding of various embodiment of the present disclosure. It will be apparent to one skilled in the art, however, that these specific details need not be employed to practice various embodiments of the present disclosure. In other instances, well known components or methods have not been described in detail to avoid unnecessarily obscuring various embodiments of the present disclosure.
(22) As disclosed herein, a eutectic bonding tool includes a stage and a carrier, wherein the stage includes at least one vacuum aperture extending between a top surface and a bottom surface, and the bottom surface includes one or more rough surface portions. In some embodiments, the carrier includes a top surface with one or more rough surface portions and one or more smooth surface portions, wherein at least one of the carrier's smooth surface portions laterally aligns to one of the vacuum apertures when the carrier's top surface couples to and opposes the stage's bottom surface.
(23) In some embodiments, the position of the stage and of the carrier are vertically flipped such that the carrier is located above the stage, instead of below the stage, such that the stage or carrier surfaces referred to as being top surfaces may be bottom surfaces, and the stage or carrier surfaces referred to as being bottom surfaces may be top surfaces. In other words, for the purposes of this application, the terms top or bottom may be interchanged when appropriate according to the relative vertical positions of the stage and carrier. For example, the embodiment disclosed above may also be described such that the stage includes a top surface with one or more rough surface portions, and the carrier includes a bottom surface with one or more rough surface portions and one or more smooth surface portions, wherein at least one of the carrier's smooth surface portions laterally aligns to one of the vacuum apertures when the carrier's bottom surface couples to and opposes the stage's top surface.
(24) In some examples, at least one of the stage's rough surface portions frictionally couples to at least one of the carrier's rough surface portions such that frictional force counteracts lateral movement of the carrier relative to the stage. Accordingly, the carrier's position becomes laterally stable with respect to the stage, even when lateral slipping forces are applied during the eutectic bonding process, resulting in improved lateral alignment of the carrier with respect to the stage and increasing product yield.
(25) Some embodiments of the disclosure provide a method for vacuum coupling a carrier to a stage that includes providing a stage with a top surface, a bottom surface, and at least one vacuum aperture extending therebetween, wherein the bottom surface includes one or more rough surface portions. The method may also include providing a carrier that includes a top surface with one or more smooth surface portions and one or more rough surface portions. The method may also include laterally aligning at least one of the carrier's smooth surface portions with at least one of the stage's vacuum apertures and vacuum coupling the carrier to the stage by bringing the carrier's top surface in contact with the stage's bottom surface and removing air pressure from the vacuum apertures.
(26) In some examples, the method also includes heating the stage using a direct heat source, such as a stage heater. In other examples, the method includes heating the stage using an indirect heat source. Providing heat to the stage may enable heating the carrier and any componentssuch as a COSA or a sliderthat are coupled to the carrier. Accordingly, providing heat to the stage, carrier, and any attached component may enable a eutectic bonding process by liquefying any eutectic alloy layered between the components.
(27) In some embodiments, the method also includes laterally aligning at least one of the carrier's rough surface portions with at least one of the stage's rough surface portions. In some examples, the method also includes frictionally coupling at least one of the carrier's rough surface portions to at least one of the stage's rough surface portions such that frictional force counteracts lateral movement of the carrier relative to the stage, for example, when vertical pressure is applied to the carrier and stage to eutectic bond a COSA to a slider. In some examples, the carrier may be a chip carrier that may hold and stabilize the COSA, or other integrated circuit. In other examples, the carrier may be a slider carrier that may hold and stabilize a slider. Some embodiments may incorporate two sets of stages and carriersone top set relative to holding, aligning, and stabilizing a COSA carrier coupled to a COSA, and one bottom set relative to holding, aligning, and stabilizing a slider carrier coupled to a slider head. Together, the two stage and carrier sets may be configured, as disclosed herein, to align the COSA with respect to the slider and provide opposing pressure to the COSA and slider, while also providing heat sufficient to enable eutectic bonding of the COSA to the slider.
(28)
(29) In some embodiments, stage 100 may be configured to be mechanically positioned with respect to its lateral or vertical axes. In some embodiments, stage 100 includes a direct heat source to provide heat to the stage, as well as to carrier 110 and component 120. In other embodiments, an indirect heat source may be configured to provide heat to stage 100, carrier 110, and component 120.
(30) Still referring to
(31) In some examples, component 120 may be affixed to carrier 110 using other mechanical coupling technologies such as form fitting, snap-fitting, press-fitting, or other coupling techniques as known in the art. Similarly, carrier 110 may be affixed to stage 100 using other mechanical coupling technologies such as form fitting, snap-fitting, press-fitting, or other coupling techniques as known in the art.
(32) Still referring to
(33) As further illustrated by
(34) In some embodiments, stage 150 may be configured to be mechanically positioned with respect to its lateral or vertical axes. In alternate embodiments, stage 150 may be fixed on its vertical axis, but may be configured for mechanical positioning along its lateral axes. Still in other embodiments, stage 150 may be fixed both vertically and laterally allowing alignment of components 120 and 170 to be controlled entirely through lateral and vertical positioning of stage 100. Stage 150 may include a direct heat source to provide heat to the stage, as well as to carrier 160 and component 170. As either an alternative to, or a supplement of the direct heat source, the bonding device may include an indirect heat source configured to provide heat to stage 150, carrier 160, and component 170.
(35) Still referring to
(36) In some examples, component 170 may be affixed to carrier 160 using other mechanical coupling technologies such as form fitting, snap-fitting, press-fitting, or other coupling techniques as known in the art. Similarly, carrier 160 may be affixed to stage 150 using other mechanical coupling technologies such as form fitting, snap-fitting, press-fitting, or other coupling techniques as known in the art.
(37)
(38)
(39) Similarly, slider carrier 260 includes a top surface 262 and a bottom surface 264. Slider carrier bottom surface 264 may mechanically couple to bond slider stage 250. For example, the slider carrier may vacuum couple to the bond slider stage when slider carrier bottom surface 264 contacts vacuum aperture 252 and a vacuum is supplied through vacuum aperture 252, the vacuum being supplied by removing air pressure from the opposite end of the vacuum aperture 252. Alternatively, the slider carrier may couple to the bond slider stage using other mechanical coupling techniques as known in the art.
(40)
(41) Similarly, slider 270 mechanically couples to slider carrier 260, and indirectly to bond slider stage 250. For example, slider 270 may vacuum couple to slider carrier 260 using a vacuum created in vacuum aperture 254, as illustrated in
(42)
(43)
(44)
(45) In some embodiments, rough surface portions 305 may have a roughness of between 50 nm and 150 nm when measuring the average vertical distance between the peaks and valleys of the surface topography. Similarly, rough surface portions 315 may also have a roughness of between 50 nm and 150 nm. Smooth surface portions 317 may have a roughness of less than 50 nm. The roughness of rough surface portions 305 and 315 may be varied such that it is less than 50 nm, or more than 150 nm depending on the size and weight of carrier 310 and stage 300, as well as the type of bonding process and degree of bonding force required. Greater roughness will limit lateral slippage when greater bonding pressure is applied, or when larger and/or heavier carriers are utilized. Similarly, the roughness of smooth surface portions 317 may be varied, or increased to 50 nm or more depending on the level of vacuum that is required to maintain an efficient seal between the carrier and the stage. Rough surface portions 305 and 315 may be formed using various surface processing technologies as known in the art, including for example, sand blasting, chemical etching, or ion etching.
(46)
(47)
(48)
(49)
(50)
(51)
(52) Although described above in terms of various exemplary embodiments and implementations, it should be understood that the various features, aspects and functionality described in one or more of the individual embodiments are not limited in their applicability to the particular embodiment with which they are described, but instead can be applied, alone or in various combinations, to one or more of the other embodiments of the application, whether or not such embodiments are described and whether or not such features are presented as being a part of a described embodiment. Thus, the breadth and scope of the present application should not be limited by any of the above-described exemplary embodiments.
(53) The terms over, under, between, and on as used herein refer to a relative position of one media layer with respect to other layers. As such, for example, one layer disposed over or under another layer may be directly in contact with the other layer or may have one or more intervening layers. Moreover, one layer disposed between two layers may be directly in contact with the two layers or may have one or more intervening layers. In contrast, a first layer on a second layer is in contact with that second layer. Additionally, the relative position of one layer with respect to other layers is provided assuming operations are performed relative to a substrate without consideration of the absolute orientation of the substrate.
(54) Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term including should be read as meaning including, without limitation or the like; the term example is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; the terms a or an should be read as meaning at least one, one or more or the like; and adjectives such as conventional, traditional, normal, standard, known and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, where this document refers to technologies that would be apparent or known to one of ordinary skill in the art, such technologies encompass those apparent or known to the skilled artisan now or at any time in the future.
(55) The presence of broadening words and phrases such as one or more, at least, but not limited to or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. The use of the term module does not imply that the components or functionality described or claimed as part of the module are all configured in a common package. Indeed, any or all of the various components of a module, whether control logic or other components, can be combined in a single package or separately maintained and can further be distributed in multiple groupings or packages or across multiple locations.
(56) Additionally, the various embodiments set forth herein are described in terms of exemplary block diagrams, flow charts and other illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives can be implemented without confinement to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration.