High porosity aerogel bonding layer for hybrid bonding yield improvement and thermal barrier

Abstract

Embodiments of the present disclosure generally relate to a system and method for processing substrates, in particular, integrating an aerogel layer into a device structure to increase hybrid bond yield. In some embodiments, a bonded component includes a first dielectric layer over a surface of a first substrate and a second dielectric layer over a surface of a second substrate. The bonded component further includes a plurality of interconnects between the first dielectric layer and the second dielectric layer. The bonded component further includes an aerogel portion between the first dielectric layer and the second dielectric layer and around the plurality of interconnects.

Description

PATENTAttorney Docket No. 44024746WO01HIGH POROSITY AEROGEL BONDING LAYER FOR HYBRID BONDING YIELD IMPROVEMENT AND THERMAL BARRIER BACKGROUNDField

[0001] Embodiments of the present disclosure generally relate to a system and method for processing substrates, in particular, integrating an aerogel layer into a device structure to increase hybrid bond yield.Description of the Related Art

[0002] During a hybrid bonding process a die may include a dielectric layer formed over a substrate. The substrate may also include multiple layers of dielectric materials and metal wiring known as back-end-of-the line (BEOL) layers. Interconnect structures can be etched and arranged into the dielectric layer and form bonding surfaces between the interconnect structures. The bonding surfaces are positioned so that interconnect structures of opposing dies can be mated to one other.

[0003] The etched interconnect structures are filled with a conductive material such that the opposing interconnect structures of opposing dies can be mated and form interconnects. The conductive material is deposited over the dielectric layer, fills the interconnect structures, and covers the dielectric layer. Then a chemical mechanical polishing (CMP) process is performed to remove a portion of the conductive material from bonding surfaces to re-expose them and form / expose electrically conductive pads (herein described as “pads”) in the interconnect structures. After the CMP process, the substrate undergoes cleaning and other bonding processes. To cause the pads to mate, a post-bond annealing process is used to cause the conductive material on each die to expand, contact, and diffuse into one another.

[0004] However, due to limited thermal budgets of memory devices, current postbonding annealing processes are performed at temperature ranges that may cause warpage of the structure and reduced bonding yield between pads. Furthermore, inefficient cleaning processes can leave behind foreign objects and / or debris that can further hinder the bonding yield between pads.

[0005] Thus, there is a need to develop new hybrid bonding processes and materials to increase the bonding yield between pads.PATENTAtorney Docket No. 44024746WO01SUMMARY

[0006] Embodiments of the present disclosure generally relate to a system and method for processing substrates, in particular, integrating an aerogel layer into a device structure to increase hybrid bond yield.

[0007] In some embodiments, a method of forming a bonded component includes forming an arrangement of interconnect pillars on a dielectric layer disposed over a substrate. The method further includes disposing a sol-gel layer over the arrangement of interconnect pillars. The method further includes removing solvent from the sol-gel layer to produce an aerogel layer. The method further includes planarizing a surface of at least the aerogel layer to prepare an exposed portion of the arrangement of interconnect pillars and form a first base structure. The method further includes aligning the exposed portion of the arrangement of interconnect pillars of the first base structure with an exposed portion of an arrangement of interconnect pillars of a second base structure. The method further includes bonding the exposed portion of the arrangement of interconnect pillars of the first base structure with the exposed portion of the arrangement of interconnect pillars of the second base structure to form a structural configuration. The method further includes annealing the structural configuration to form a bonded component.

[0008] In some embodiments, a bonded component includes a first dielectric layer over a surface of a first substrate and a second dielectric layer over a surface of a second substrate. The bonded component further includes a plurality of interconnects between the first dielectric layer and the second dielectric layer. The bonded component further includes an aerogel portion between the first dielectric layer and the second dielectric layer and around the plurality of interconnects.

[0009] In some embodiments, a method of forming a bonded component includes aligning a first structure and a second structure. Both the first structure and the second structure include a plurality of interconnect pillars in contact with a dielectric layer. The dielectric layer is disposed over a substrate. At least one of the first structure and the second structure include an aerogel layer disposed over a surface of the dielectric layer and around the plurality of interconnect pillars. Both the first and second structures include a surface having an exposed portion of the plurality of interconnect pillars. The method further includes bonding the exposed portion of the of the pluralityPATENTAtorney Docket No. 44024746WO01of interconnect pillars of the first structure with the exposed portion of the of the plurality of interconnect pillars of the second structure to form a structural configuration. The method further includes annealing the structural configuration to form a bonded component.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] So that the manner in which the above recited features of embodiments of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.

[0011] Figure 1 is a process flow diagram of a method, according to embodiments described herein.

[0012] Figure 2A is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0013] Figure 2B is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0014] Figure 2C is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0015] Figure 2D is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0016] Figure 2E is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0017] Figure 2F is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0018] Figure 2G is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0019] Figure 3A is a cross-sectional illustration of a device structure, in accordance with an embodiment.PATENTAtorney Docket No. 44024746WO01

[0020] Figure 3B is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0021] Figure 3C is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0022] Figure 4A is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0023] Figure 4B is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0024] Figure 4C is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0025] Figure 5A is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0026] Figure 5B is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0027] Figure 5C is a cross-sectional illustration of a device structure, in accordance with an embodiment.

[0028] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.DETAILED DESCRIPTION

[0029] The present disclosure describes methods and processes to form device structures with increased hybrid bond yield and thermal barrier properties. More specifically, an aerogel layer is integrated into such device structures prior to planarization and bonding processes to act as a bonding layer for hybrid bonding of device components. The matched coefficient of thermal expansion of the aerogel layer results in reduced warpage during high temperature annealing processes. Additionally, the high porosity of the aerogel layer increases the tolerance of such components and processes to the inclusion of foreign materials, thereby reducing the length scale of void formation. Through the integration of the aerogel layer, thePATENTAtorney Docket No. 44024746WO01resulting devices having enhanced hybrid bonding yield, as a result of improved thermal stability, yielding reduced warpage and higher tolerances towards the presence of foreign materials during bonding processes.

[0030] Figure 1 is a process flow diagram of a method 100 for hybrid bonding, according to one or more embodiments. Figures 2A-2G are schematic cross-sectional diagrams of a packaged device during / throughout a hybrid bonding process, according to an embodiment.

[0031] The method 100 includes a series of operations that may be conducted individually, simultaneously, in multiplicity, in repetition, and / or any suitable order to prepare a packaged device. It should understood that the operations for hybrid bonding are not limited to just those described herein, but may also include any one or more operations known to one of ordinary skill in the art.

[0032] In operation 110 of the method 100, an arrangement of interconnect pillars 206 are formed on a dielectric layer 204 disposed over a substrate 202 to prepare a structure 200a, as illustrated in Figure 2A. In some embodiments, the substrate is selected from any one or more suitable substrates, such as a base substrate, a silicon wafer, and / or one of numerous patterned device structures (dies or chips) formed across a base substrate. The substrate may include multiple layers of metal wiring in insulating dielectrics that are commonly referred to as the Back-End-of-Line (BEOL) layers. The dielectric layer 204 may comprise an inorganic dielectric material layer such as oxide, nitride, oxynitride, oxycarbide, carbides, carbonitrides, diamond, diamond like materials, glasses, ceramics, glass-ceramics, and the like. In one or more embodiments, the dielectric layer 204 is a layer deposited specifically for hybrid bonding and / or is the last of the BEOL layers.

[0033] The arrangement of interconnect pillars 206 may be formed via any one or more suitable methods known to one of ordinary skill in the art, such as a plate up process. Each of the pillars in the arrangement of pillars may be composed of the same interconnect material, or individually composed of different interconnect materials. The pillars of the arrangement of interconnect pillars 206 may be positioned, configured, and / or oriented in any suitable manner necessary for proper function and / or fabrication of an intended device.PATENTAtorney Docket No. 44024746WO01

[0034] An individual pillar 206a of the arrangement of interconnect pillars 206 may include any suitable shape and / or size necessary for proper function and / or fabrication of an intended device. In some embodiments, an individual pillar 206a has a height 207a of about 500 nm to about 10 pm, such as about 1 pm to about 5 pm, such as about 2 pm to about 4 pm, alternatively about 500 nm to about 1 pm, alternatively about 1 pm to about 2 pm, alternatively about 2 pm to about 3 pm, alternatively about 3 pm to about 4 pm, alternatively about 4 pm to about 5 pm, alternatively about 5 pm to about 10 pm. In some embodiments, an individual pillar 206a has a width 207b of about 30% to 70% of the pitch resulting in typical pad sizes of about 20 pm or less, such as about 1 pm or less, such as about 1 pm to about 20 pm, such as about 5 pm to about 15 pm, such as about 7.5 pm to about 12.5 pm, alternatively about 1 pm to about 5 pm, alternatively about 5 pm to about 7.5 pm, alternatively about 7.5 pm to about 10 pm, alternatively about 10 pm to about 12.5 pm, alternatively about 12.5 pm to about 15 pm, alternatively about 15 pm to about 20 pm. In one or more embodiments, an individual pillar has an aspect ratio (height 207a : width 207b) of about 1 : 1 to about 5: 1 , such as about 2: 1 to about 4: 1 , alternatively about 1 : 1 to about 2:1, alternatively about 2:1 to about 3:1, alternatively about 3:1 to about 4:1, alternatively about 4:1 to about 5:1. An individual pillar 206a of the arrangement of interconnect pillars 206 may be composed of a suitable interconnect material (e.g., copper, silver, gold, indium) independent of the material composition of the remaining pillars in the arrangement of interconnect pillars 206. In at least one embodiment, each pillar of the arrangement of interconnect pillars 206 is composed of the same interconnect material. In some embodiments, the arrangement of interconnect pillars 206 is coated with a barrier layer composed of SiNx, Ru, and / or combinations thereof. In at least one embodiment, at least one of the individual pillars 206a of the arrangement of interconnect pillars 206 has a recessed top surface, as shown in Figure 2A.

[0035] In operation 120 of the method 100, a sol-gel layer 208 is disposed over the exposed surfaces of the dielectric layer 204 and the arrangement of interconnect pillars 206 to form a structure 200b, as illustrated in Figure 2B. The sol-gel layer 208 may be disposed over the surface of the dielectric layer 204 and the arrangement of interconnect pillars 206 via any suitable method, such as spin-coating, dip-coating, spray-coating, slot-die coating, drop-casting, solvent-casting, and the like. In somePATENTAtorney Docket No. 44024746WO01embodiments, the sol-gel is a silica sol-gel prepared by addition of a catalyst to a silica precursor solution in a solvent. The silica precursor may include, but is not limited to, tetraethylorthosilicate (TEOS), tetramethylorthosilicate (TMOS), methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTMS), methyltriethoxysilane (MTES), silbond H-5, polyethoxydisiloxane (PEDS), and combinations thereof. The catalyst may include, but is not limited to, hydrofluoric acid (HF), hydrogen chloride (HCI), nitric acid (HNO3), sulfuric acid (H2SO4), oxalic acid (C2H2O4), acetic acid (CH3COOH), trifluoroacetic acid (TFA), ammonium hydroxide (NH4OH), and combinations thereof. The solvent may include, but is not limited to, methanol, ethanol, isopropanol, and combinations thereof. In some embodiments, the sol-gel layer has a solids content of about 0.01 M to about 0.2 M, such as about 0.05 M to about 0.15 M, such as about 0.08 M to about 0.12 M, alternatively about 0.01 M to about 0.05 M, alternatively about 0.05 M to about 0.08 M, alternatively about 0.08 M to about 0.1 M, alternatively about 0.1 M to about 0.12 M, alternatively about 0.12 M to about 0.15 M, alternatively about 0.15 M to about 0.2 M. In some embodiments, the sol-gel layer 208 includes a height 209 of about 1 pm to about 25 pm, such as about 5 pm to about 20 pm, such as about 10 pm to about 15 pm, alternatively about 1 pm to about 5 pm, alternatively about 5 pm to about 10 pm, alternatively about 15 pm to about 20 pm, alternatively about 20 pm to about 25 pm.

[0036] In operation 130 of the method 100, the solvent is removed from the sol-gel layer 208 to produce an aerogel layer 210 and form a structure 200c, as shown in Figure 2C. The solvent may be removed from the sol-gel layer 208 via any one or more suitable drying processes capable of removing the solvent therefrom to produce an aerogel layer 210, such as a silica-containing aerogel layer. In some embodiments, the drying process of operation 130 includes one or more of supercritical CO2 drying, freeze drying, pressure drying (e.g., ambient pressure drying), and the like. The resulting aerogel layer 210 may have a porosity, corresponding to the nanoscale air gaps produced from the drying process, of about 90% or greater. In some embodiments, the resulting aerogel layer 210 has a coefficient of thermal expansion (CTE) of about 0.1 parts per million per °C (ppm) to about 10 ppm, such as about 0.5 ppm to about 5 ppm, such as about 1 ppm to about 3 ppm, alternatively about 0.1 ppm to about 0.5 ppm, alternatively about 0.5 ppm to about 1 ppm, alternatively about 1 ppm to about 2 ppm, alternatively about 2 ppm to about 3 ppm, alternatively about 3PATENTAtorney Docket No. 44024746WO01ppm to about 5 ppm, alternatively about 5 ppm to about 10 ppm. In some embodiments, the resulting aerogel layer has an average pore size of about 1 nm to about 500 nm, such as about 50 nm to about 400 nm, such as about 100 nm to about 300 nm, such as about 150 nm to about 250 nm, alternatively about 1 nm to about 50 nm, alternatively about 50 nm to about 100 nm, alternatively about 100 nm to about 150 nm, alternatively about 150 nm to about 200 nm, alternatively about 200 nm to about 250 nm, alternatively about 250 nm to about 300 nm, alternatively about 300 nm to about 400 nm, alternatively about 400 nm to about 500 nm.

[0037] At operation 140 of the method 100, the surface of the structure 200c is planarized to expose a portion of the arrangement of interconnect pillars 206 to form structure 200d, as shown in Figure 2D. The planarization process of operation 140 may include a chemical mechanical polishing (CMP) process. The CMP process is performed to remove a portion of the conductive material from bonding surfaces to reexpose them and form / expose electrically conductive pads (herein described as “pads”) in the interconnect structures. Performing the CMP process includes finishing the field region of the aerogel layer 210 to meet dielectric roughness specifications. As shown in Figure 2D, the CMP process removes portions of the array of interconnect pillars 206 in the field region of the aerogel layer 210 and exposes pads in the array of interconnect pillars 206. The pads are configured to bond with corresponding pads of corresponding patterned interconnect structures formed on the same substrate or a different substrate to form bonded interconnect structures. The pads are exposed through openings etched in the aerogel layer 210. In at least one embodiment, at least one of the individual pillars 206a of the arrangement of interconnect pillars 206 has a recessed top surface below the surface of the aerogel layer 210, as shown in Figure 2D.

[0038] In some embodiments, a cleaning process is performed on the structure 200d subsequent the CMP process. In at least one embodiment, the cleaning process is performed in the CMP processing system. That is to say, the CMP process and the cleaning process may be performed in the same CMP processing system. The cleaning process is performed to remove residual foreign material from the surface of the structure 200d that may result from one or more operations described herein.PATENTAtorney Docket No. 44024746WO01

[0039] At operation 150 of the method 100, the exposed portion of the arrangement of interconnect pillars 222a of a first structure 220a (e.g., a structure 200d) are aligned with the arrangement of interconnect pillars 222b of a second structure 220b to form an aligned configuration 200e, as shown in Figure 2E. As such, the aerogel layer 224a of the first structure 220a and the aerogel layer 224b of the second structure 220b are also aligned.

[0040] At operation 160 of the method 100, the exposed portion of the arrangement of interconnect pillars 222a of a first structure 220a of the aligned configuration 200e is brought into contact with the exposed portion of the arrangement of interconnect pillars 222b of a second structure 220b of the aligned configuration 200e to form a structural configuration 200f, as shown in Figure 2F. Additionally and / or alternatively, the aerogel layer 224a of the first structure 220a of the aligned configuration 200e is brought into contact with the aerogel layer 224b of the second structure 220b of the aligned configuration 200e and bonded thereto to form the structural configuration 200f shown in Figure 2F.

[0041] In some embodiments, the bonding process of operation 160 includes a plasma activation process to bond the aerogel layer 224a of the first structure 220a with the aerogel layer 224b of the second structure 220b. During the plasma activation process, both the first structure 220a and the second structure 220b of the aligned configuration 200e are exposed to a plasma, which bombards the surface of each structure (e.g., the first structure 220a and the second structure 220b). During the plasma activation process, the surfaces of the structures (e.g., the first structure 220a and the second structure 220b) are exposed to charged particles such as ions and electrons within the plasma, thereby creating reactive sites that increase surface energy and wettability. Such increases in surface energy and wettability promote better adhesion and bonding quality in the hybrid bonding process. More specifically, the plasma activation process bonds the aerogel layer 224a of the first structure 220a with the aerogel layer 224b of the second structure 220b in such a manner that the exposed pads of the first structure 220a and the second structure 220b are aligned with one another, as illustrated by the structural configuration 200f depicted in Figure 2F.PATENTAtorney Docket No. 44024746WO01

[0042] At operation 170 of the method 100, the structural configuration 200f is subjected to an annealing process to bond the arrangement of interconnect pillars 222a of a first structure 220a with the arrangement of interconnect pillars 222b of a second structure 220b to form a bonded structure 200g, as shown in Figure 2G. The first structure 220a of the structural configuration 200f and the second structure 220b of the structural configuration 200f are bonded in such a manner that the pads of the exposed portion of the arrangement of interconnect pillars 222a and the arrangement of interconnect pillars 222b are bonded to form an arrangement of interconnects 232, as shown in Figure 2G.

[0043] Conventionally, annealing processes are performed at temperature ranges that may cause warpage of the structure and reduced bonding yield between pads of commonly used device components, as conventional dielectric gapfill layers lack the thermal stability required for such processes (e.g., a CTE lower than that of the arrangement of interconnect pillars 222a and 222b). In contrast, the aerogel layers 224a and 224b may be prepared from such materials and / or processes to produce aerogel layers having a CTE less than that of the arrangement of interconnect pillars 222a and 222b. Without being bound by theory, the CTE of the aerogel layers 224a and 224b (in comparison to conventional dielectric gapfill layers and / or materials) relative to the CTE of the arrangement of interconnect pillars 222a and 222b result in limited or no warpage of the first structure 220a, the second structure 220b, and / or the resulting bonded structure 200g during and / or as a result of the bonding process of operation 170. Such reductions in warpage, as compared to conventional dielectric gapfill layers and / or devices formed therefrom, result in enhanced bonding yield between the pads of the exposed portion of the arrangement of interconnect pillars 222a and the arrangement of interconnect pillars 222b.

[0044] In some embodiments, the cleaning process subsequent the CMP process of operation 140 does not sufficiently remove the residual foreign materials from the surface of the structure 200d. Such insufficient removal of the foreign material 302 can result in such material being present in the aligned configuration 300a prepared via the aligning step of operation 150, as shown in Figure 3A. In conventional fabrication and bonding processes, the presence of foreign materials (e.g., foreign material 302) can result in void formation and hinder bonding of the interconnect structures. In contrast, the porosity of the aerogel layers 224a and 224b canPATENTAtorney Docket No. 44024746WO01accommodate the inclusion of the foreign material 302 therein during the bonding process of operation 160 to form the structural configuration 300b, as shown in Figure 3B. The inclusion of the foreign material 302 into the aerogel layers 224a and 224b result in the integration of the foreign material 302 into the aerogel portion 234 of the bonded structure 300c resulting from the annealing process of operation 170, as shown in Figure 3C. Such integration of the foreign material 302 into the aerogel portion 234 of the bonded structure 300c results in reduced void formation and enhanced contact and bonding yield between the pads of the exposed portion of the arrangement of interconnect pillars 222a and the arrangement of interconnect pillars 222b.

[0045] In some embodiments, an aligned configuration 400a can include a first structure 220a aligned with a second structure 402. The second structure 402 may include arrangement of interconnect pillars 404 disposed in and / or etched into a dielectric layer 204 disposed over a substrate 202, as shown in Figure 4A. The arrangement of interconnect pillars 404 of the second structure 402 may be formed using any suitable etching or deposition process, such as a damascene etching process. In some embodiments, a surface of the second structure 402 includes an exposed portion of the arrangement of interconnect pillars 404 arrangement of interconnect pillars 404.

[0046] In operation 150 of the method 100, the exposed portion of the arrangement of interconnect pillars 222a of a first structure 220a are aligned with the arrangement of interconnect pillars 404 of a second structure 402 to form an aligned configuration 400a, as shown in Figure 4A. As such, the aerogel layer 224a of the first structure 220a and the dielectric layer 204 of the second structure 402 are also aligned.

[0047] At operation 160 of the method 100, the exposed portion of the arrangement of interconnect pillars 222a of a first structure 220a of the aligned configuration 400a is brought into contact with the exposed portion of the arrangement of interconnect pillars 404 of a second structure 402 of the aligned configuration 400a to form a structural configuration 400b, as shown in Figure 4B. Additionally and / or alternatively, the aerogel layer 224a of the first structure 220a of the aligned configuration 400a is brought into contact with the dielectric layer 204 of the second structure 402 of the aligned configuration 400a and bonded thereto via a bonding process (e.g., a plasmaPATENTAtorney Docket No. 44024746WO01activation process) to form the structural configuration 400b shown in Figure 4B. In at least one embodiment, the first structure 220a of the structural configuration 400b and the second structure 402 of the structural configuration 400b are bonded in such a manner that the field portions of the aerogel layer 224a and the dielectric layer 204 form an interfacial connection, as shown in Figure 4B. Without being bound by theory, the ability to form an interfacial connection between aerogel layer 224a and the dielectric layer 204 further highlight the utility of implementing an aerogel composition in such bonding processes.

[0048] At operation 170 of the method 100, the structural configuration 400b is subjected to annealing process to bond the exposed portion of the arrangement of interconnect pillars 222a of the first structure 220a of the structural configuration 400b with the arrangement of interconnects 406 of the second structure 402 of the structural configuration 400b to form a bonded structure 400c, as shown in Figure 4C. The first structure 220a of the structural configuration 400b and the second structure 402 of the structural configuration 400b are bonded in such a manner that the pads of the exposed portion of the arrangement of interconnect pillars 222a and the arrangement of interconnect pillars 404 are bonded to form an arrangement of interconnects 406, as shown in Figure 4C.

[0049] As previously described, the cleaning process subsequent the CMP process of operation 140 may not sufficiently remove the residual foreign materials from the surface of the structure 200d. Such insufficient removal of the foreign material 502 can result in such material being present in the aligned configuration 500a prepared via the aligning the first structure 220a and the second structure 402 via operation 150, as shown in Figure 5A. In conventional fabrication and bonding processes, the presence of foreign materials (e.g., foreign material 502) can result in void formation and hinder bonding of the interconnect structures. In contrast, the porosity of the aerogel layer 224a can accommodate the inclusion of the foreign material 502 therein during the bonding process of operation 160 to form the structural configuration 500b from the first structure 220a and the second structure 402, as shown in Figure 5B. The inclusion of the foreign material 502 into the aerogel layer 224a of the first structure 220a result in the integration of the foreign material 502 into the aerogel portion 408 of the bonded structure 500c resulting from the annealing process of operation 170, as shown in Figure 5C. Such integration of the foreign material 502PATENTAtorney Docket No. 44024746WO01into the aerogel portion 408 of the bonded structure 500c results in reduced void formation and enhanced contact and bonding yield between the pads of the exposed portion of the arrangement of interconnect pillars 222a and the arrangement of interconnect pillars 404.

[0050] Overall, the present disclosure relates to the formation of bonded structures and devices having enhanced hybrid bonding yield, as a result of improved thermal stability, yielding reduced warpage and higher tolerances towards the presence of foreign materials during bonding processes. More specifically, the present disclosure exploits the low CTE and high porosity of aerogel materials to enhance hybrid bonding yield via the integration of such materials into device structures prior to planarization and bonding processes.

[0051] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The present disclosure also contemplates that one or more aspects of the embodiments described herein may be substituted in for one or more of the other aspects described. The scope of the disclosure is determined by the claims that follow.

[0052] Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It should be appreciated that ranges including the combination of any two values, e.g., the combination of any lower value with any upper value, the combination of any two lower values, and / or the combination of any two upper values are contemplated unless otherwise indicated. Certain lower limits, upper limits and ranges appear in one or more claims below.

Claims

PATENTAtorney Docket No. 44024746WO01We claim:

1. A method of forming a bonded component, comprising:forming an arrangement of interconnect pillars on a dielectric layer disposed over a substrate;disposing a sol-gel layer over the arrangement of interconnect pillars; removing solvent from the sol-gel layer to produce an aerogel layer; planarizing a surface of at least the aerogel layer to prepare an exposed portion of the arrangement of interconnect pillars and form a first base structure;aligning the exposed portion of the arrangement of interconnect pillars of the first base structure with an exposed portion of an arrangement of interconnect pillars of a second base structure;bonding the exposed portion of the arrangement of interconnect pillars of the first base structure with the exposed portion of the arrangement of interconnect pillars of the second base structure to form a structural configuration; andannealing the structural configuration to form a bonded component.

2. The method of claim 1, wherein the arrangement of interconnect pillars comprises a plurality of pillars.

3. The method of claim 2, wherein the at least one of the plurality of pillars comprises an aspect ratio (heightwidth) of about 1:1 to about 5:1.

4. The method of claim 1, wherein the sol-gel comprises a silica precursor, a solvent and a catalyst.

5. The method of claim 1, wherein the aerogel comprises a coefficient of thermal expansion (CTE) of about 0.1 ppm to about 10 ppm.

6. The method of claim 1 , wherein the aerogel comprises a porosity of about 90% or greater.

7. The method of claim 1, wherein the aerogel comprises an average pore size of about 1 nm to about 500 nm.PATENTAtorney Docket No. 44024746WO018. The method of claim 1, wherein the planarizing a surface comprises a chemical mechanical polishing (CMP) process.

9. A bonded component, comprising:a first dielectric layer over a surface of a first substrate;a second dielectric layer over a surface of a second substrate;a plurality of interconnects between the first dielectric layer and the second dielectric layer; andan aerogel portion between the first dielectric layer and the second dielectric layer and around the plurality of interconnects.

10. The bonded component of claim 9, wherein at least one of the plurality of interconnects comprises an aspect ratio (heightwidth) of about 1 :1 to about 5:1.

11. The bonded component of claim 9, wherein the aerogel comprises a coefficient of thermal expansion (CTE) of about 0.1 ppm to about 10 ppm.

12. The bonded component of claim 9, wherein the aerogel comprises a porosity of about 90% or greater.

13. The bonded component of claim 9, wherein the aerogel comprises an average pore size of about 1 nm to about 500 nm.

14. The bonded component of claim 9, wherein the arrangement of interconnects are etched into the second dielectric layer.

15. The bonded component of claim 14, wherein the aerogel comprises a coefficient of thermal expansion (CTE) of about 0.1 ppm to about 10 ppm.

16. The bonded component of claim 14, wherein the aerogel comprises a porosity of about 90% or greater.PATENTAtorney Docket No. 44024746WO0117. The bonded component of claim 14, wherein the aerogel comprises an average pore size of about 1 nm to about 500 nm.

18. A method of forming a bonded component, comprising:aligning a first structure and a second structure, wherein:both the first structure and the second structure comprise a plurality of interconnect pillars in contact with a dielectric layer, the dielectric layer being disposed over a substrate,at least one of the first structure and the second structure comprise an aerogel layer disposed over a surface of the dielectric layer and around the plurality of interconnect pillars, andboth the first and second structure comprise a surface having an exposed portion of the plurality of interconnect pillars;bonding the exposed portion of the of the plurality of interconnect pillars of the first structure with the exposed portion of the of the plurality of interconnect pillars of the second structure to form a structural configuration; andannealing the structural configuration to form a bonded component.

19. The method of claim 18, wherein the plurality of interconnect pillars of the first structure extend from the dielectric layer of the first structure, the aerogel layer being disposed over the surface of the dielectric layer of the first structure and around the plurality of interconnect pillars of the first structure.

20. The method of claim 19, wherein the plurality of interconnect pillars of the second structure are disposed within the dielectric layer of the second structure.

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