Hybrid bonding with through substrate via (TSV)
10461069 ยท 2019-10-29
Assignee
Inventors
Cpc classification
H01L21/76895
ELECTRICITY
H01L2224/0569
ELECTRICITY
H01L2224/80121
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2224/9202
ELECTRICITY
H01L23/481
ELECTRICITY
H01L2924/0002
ELECTRICITY
H01L2224/05024
ELECTRICITY
H01L2225/06513
ELECTRICITY
H01L2224/80121
ELECTRICITY
H01L2224/0231
ELECTRICITY
H01L24/80
ELECTRICITY
H01L2224/05567
ELECTRICITY
H01L2224/80855
ELECTRICITY
H01L2224/80001
ELECTRICITY
H01L2224/80895
ELECTRICITY
H01L2224/94
ELECTRICITY
H01L2924/0002
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2225/06527
ELECTRICITY
H01L2924/00
ELECTRICITY
H01L2224/80986
ELECTRICITY
H01L2924/00
ELECTRICITY
H01L2225/06541
ELECTRICITY
H01L21/76897
ELECTRICITY
H01L2224/9202
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/80896
ELECTRICITY
H01L2224/05186
ELECTRICITY
H01L2225/06558
ELECTRICITY
H01L2224/05186
ELECTRICITY
H01L25/50
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/02372
ELECTRICITY
H01L24/89
ELECTRICITY
H01L2224/05569
ELECTRICITY
H01L2224/94
ELECTRICITY
H01L2224/80001
ELECTRICITY
International classification
H01L25/065
ELECTRICITY
H01L25/00
ELECTRICITY
H01L23/48
ELECTRICITY
Abstract
A semiconductor device structure is provided. The semiconductor device structure includes a bonding structure formed between a first substrate and a second substrate. The bonding structure includes a first polymer bonded to a second polymer, and a first conductive material bonded to a second conductive material. The semiconductor device includes a first TSV formed in the first substrate and an interconnect structure formed over the first TSV. The first TSV is between the interconnect structure and the bonding structure.
Claims
1. A semiconductor device structure, comprising: a bonding structure formed between a first substrate and a second substrate, wherein the bonding structure comprises a first polymer bonded to a second polymer, and a first conductive material bonded to a second conductive material; a first TSV formed in the first substrate; an interconnect structure formed over the first TSV, wherein the first TSV is between the interconnect structure and the bonding structure; and a first conductive layer between the first conductive material and the first TSV, wherein the first conductive layer has a first surface and a second surface, the first surface is in direct contact with the first TSV, and the second surface is in direct contact with the first polymer.
2. The semiconductor device structure as claimed in claim 1, further comprising: a first transistor formed over the first substrate; and a first contact plug formed over the first transistor, wherein the first conductive layer is in direct contact with the first TSV and the first contact plug.
3. The semiconductor device structure as claimed in claim 1, wherein the first polymer material and the second polymer material are respectively made of benzocyclobutene (BCB) polymer, polyimide (PI), or polybenzoxazole (PBO).
4. The semiconductor device structure as claimed in claim 1, wherein the first substrate has a first height, and the second substrate has a second height, and the first height is smaller than the second height.
5. The semiconductor device structure as claimed in claim 1, further comprising: a first diffusion barrier layer formed in the first polymer material, wherein the first conductive layer is between the first diffusion barrier layer and the first TSV.
6. The semiconductor device structure as claimed in claim 1, further comprising: a second TSV extending from a bottom surface of the second substrate to a second metallization structure over the second substrate.
7. A semiconductor device structure, comprising: a first metallization structure formed over a first substrate; a first bonding structure formed over the first metallization structure, wherein the first bonding structure comprises a first conductive material embedded in a first polymer material; a second bonding structure formed over a second substrate, wherein the second bonding structure comprises a second conductive material embedded in a second polymer material, the first conductive material is bonded to the second conductive material and the first polymer material is bonded to the second polymer material; a first through substrate via (TSV) extending from a bottom surface of the first substrate to the first metallization structure, wherein the first metallization structure is between the first TSV and the first polymer material; a first transistor formed over the first substrate; and a first contact plug formed over the first transistor, wherein the first metallization structure is in direct contact with the first TSV and the first contact plug.
8. The semiconductor device structure as claimed in claim 7, further comprising: a second TSV extending from a bottom surface of the second substrate to a second metallization structure over the second substrate.
9. The semiconductor device structure as claimed in claim 8, wherein a first width of the first TSV is smaller than a second width of the second TSV.
10. The semiconductor device structure as claimed in claim 7, further comprising: an interconnect structure formed over the bottom surface of the first substrate, wherein the interconnect structure is in direct contact with the first TSV.
11. The semiconductor device structure as claimed in claim 7, wherein the first polymer material and the second polymer material are respectively made of benzocyclobutene (BCB) polymer, polyimide (PI), or polybenzoxazole (PBO).
12. The semiconductor device structure as claimed in claim 7, further comprising: a first diffusion barrier layer formed in the first polymer material, wherein the first metallization structure is between the first diffusion barrier layer and the first TSV.
13. The semiconductor device structure as claimed in claim 7, wherein the first substrate has a first height, and the second substrate has a second height, and the first height is smaller than the second height.
14. A semiconductor device structure, comprising: a first substrate bonded to a second substrate via a bonding structure, wherein the bonding structure comprises a first polymer bonded to a second polymer, and a first diffusion barrier layer bonded to a second diffusion barrier layer; a first TSV extending from a bottom surface of the first substrate to a first conductive layer; a first contact plug adjacent to the first TSV, wherein the first conductive layer is in direct contact with the first TSV and the first contact plug; and a second TSV extending from a bottom surface of the second substrate to a second conductive layer over the second substrate, wherein the second conductive layer is between the second diffusion barrier layer and the second TSV.
15. The semiconductor device structure as claimed in claim 14, further comprising: a first transistor formed over the first substrate; and the first contact plug formed over the first transistor.
16. The semiconductor device structure as claimed in claim 14, further comprising: an interconnect structure formed over the bottom surface of the first substrate, wherein the interconnect structure is in direct contact with the first TSV.
17. The semiconductor device structure as claimed in claim 14, wherein the first substrate has a first height, and the second substrate has a second height, and the first height is smaller than the second height.
18. The semiconductor device structure as claimed in claim 14, wherein a first width of the first TSV is smaller than a second width of the second TSV.
19. The semiconductor device structure as claimed in claim 1, further comprising: a second transistor formed over the second substrate; a second contact plug formed over the second transistor; and a second conductive layer formed over the second contact plug, wherein the second conductive layer has a first surface and a second surface, the first surface is in direct contact with the second contact plug, and the second surface is in direct contact with the second polymer.
20. The semiconductor device structure as claimed in claim 14, wherein the first conductive layer has a first surface in contact with the first contact plug and a second surface in contact with the first polymer.
Description
BRIEF DESCRIPTION OF THE DRAWING
(1) For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
(2)
(3)
DETAILED DESCRIPTION
(4) It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of the disclosure. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. Moreover, the performance of a first process before a second process in the description that follows may include embodiments in which the second process is performed immediately after the first process, and may also include embodiments in which additional processes may be performed between the first and second processes. Various features may be arbitrarily drawn in different scales for the sake of simplicity and clarity. Furthermore, the formation of a first feature over or on a second feature in the description may include embodiments in which the first and second features are formed in direct or indirect contact.
(5)
(6) Semiconductor wafer 100 includes a semiconductor substrate 104, which may be made of silicon or other semiconductor materials. Alternatively or additionally, semiconductor substrate 104 may include other elementary semiconductor materials such as germanium. In some embodiments, semiconductor substrate 104 is made of a compound semiconductor such as silicon carbide, gallium arsenic, indium arsenide, or indium phosphide. In some embodiments, semiconductor substrate 104 is made of an alloy semiconductor such as silicon germanium, silicon germanium carbide, gallium arsenic phosphide, or gallium indium phosphide. In some embodiments, semiconductor substrate 104 includes an epitaxial layer. For example, semiconductor substrate 104 has an epitaxial layer overlying a bulk semiconductor.
(7) Referring to
(8) Device regions 103 may form various N-type metal-oxide semiconductor (NMOS) and/or P-type metal-oxide semiconductor (PMOS) devices, such as transistors or memories, and the like, which are interconnected to perform one or more functions. Other devices, such as capacitors, resistors, diodes, photo-diodes, fuses, and the like may also be formed on substrate 104.
(9) As shown in
(10) Each TSVs 400 includes a liner 410, a diffusion barrier layer 420, and a conductive material 430 in accordance with some embodiments. Liner 410 is made of an insulating material, such as oxides or nitrides. Liner 410 may be formed by using a plasma enhanced chemical vapor deposition (PECVD) process or other applicable processes. Liner 410 may be a single layer or multi-layers. In some embodiments, liner 410 has a thickness in a range from about 100 to about 5000 .
(11) Diffusion Barrier layer 420 is made of Ta, TaN, Ti, TiN, or CoW. In some embodiments, diffusion barrier layer 420 is formed by a physically vapor deposition (PVD) process. Conductive material 430 is made of copper (Cu), copper alloy, aluminum (Al), aluminum alloys, or combinations thereof. Alternatively, other applicable materials may be used. In some embodiments, conductive material 430 is formed by plating.
(12) With high aspect ratio, filling materials into the TSV opening becomes challenging. Voids may form in a TSV opening. In addition, due to insufficient sidewall coverage of liner 410 or diffusion barrier layer 420, some extrusion or diffusion problems related to conductive via material 430 may occur. In contrast, as shown in
(13) In addition, width W.sub.1 of TSVs 400 is reduced along with a decrease of depth D.sub.1 of TSVs 400. When distance W.sub.2 is smaller, a larger area of device regions 103 may be used. As a result, integrated intensity of the devices in device regions 103 is further improved.
(14) In some embodiments, semiconductor wafer 100 has a height H.sub.1 from a bottom surface 104b of semiconductor substrate 104 to a top surface of gate structure 109 in a range from about 1 m to about 20 m. In some embodiments, TSVs 400 have a width W.sub.1 in a range from about 0.025 m to about 2 m. In some embodiments, TSVs 400 have a depth D.sub.1 in a range from about 0.2 m to about 10 m. In some embodiments, TSVs 400 have an aspect ratio (D.sub.1/W.sub.1) in a range from about 2 to about 15.
(15) In addition, devices in the vicinity of the TSV suffer from serious performance degradation due to the stress induced by the TSV. A keep-out zone (KOZ) is used to define a region where no devices could be placed within. In some embodiments, keep-out zone (KOZ) is defined by a distance W.sub.2, which is measured from a sidewall 400a of TSV 400 to a nearest gate structure 209. Since the depth D.sub.1 of TSVs 400 is made smaller, a smaller width W.sub.1 is achieved. Therefore, overall stress induced by TSVs 400 is reduced. In some embodiments, distance W.sub.2 is in a range from 0.01 m to about 3 In some embodiments, when width W.sub.1 of TSVs 400 is reduced to a range from about 2 m to about 3 m, the stress induced by TSV can almost be ignored.
(16) As shown in
(17) A bonding structure 142 is formed over metallization structure 122. Bonding structure 142 includes a conductive material 144 embedded in a polymer material 146. Conductive material 144 is contact pad (or bond pad) formed on a top surface of semiconductor wafer 100. Conductive features 124 are connected to conductive material 144. Conductive material 144 may be made of conductive materials, such as copper (Cu), copper alloy, aluminum (Al), aluminum alloy, or combinations thereof. Other applicable materials may be used as conductive material 144.
(18) In some embodiments, if conductive material 144 is made of a metal, such as copper, which is easy to diffuse, a diffusion barrier layer 143 is needed. Diffusion barrier layer 143 may be made of silicon nitride (SiN), silicon oxynitride (SiON), titanium nitride (TiN), tantalum nitride (TaN), or aluminum nitride (AlN). In some embodiments, conductive material 144 is made of copper, and diffusion barrier layer 143 is made of Ti, TiN, Ta, TaN, Ta/TaN, COP or CoW. In some embodiments, diffusion barrier layer 143 has a thickness in a range from about 5 to about 1000 .
(19) In some embodiments, polymer material 146 is benzocyclobutene (BCB) polymer, polyimide (PI), or polybenzoxazole (PBO). In some embodiments, polymer material 146 is made of benzocyclobutene (BCB) polymer and is applied to metallization structure 122 by spin coating. Since benzocyclobutene polymer is a soft material, it can tolerant more stress resulting from the TSV formed in the subsequent processes, compared to other dielectric materials such as silicon dioxide.
(20) As shown in
(21) Semiconductor wafer 200 further includes a metallization structure 222 and a bonding structure 242. Metallization structure 222 is similar to metallization structure 122 and includes a contact plug 214 embedded in a dielectric layer 207 and conductive features 224 embedded in an insulating material 226. Contact plug 214 is similar to contact plug 114, and dielectric layer 207 is similar to dielectric layer 107. Conductive features 224 are similar to conductive features 124, and insulating material 226 is similar to insulating material 126. Bonding structure 242 is similar to bonding structure 142 and includes a conductive material 244 and a polymer material 246. Conductive material 244 is similar to conductive material 144, and polymer material 246 is similar to polymer material 146. Metallization structure 222 may further include a diffusion barrier layer 243 which is similar to diffusion barrier layer 143.
(22) Before semiconductor wafer 100 is bonded to semiconductor 200, semiconductor wafers 100 and 200 are aligned, such that conductive material 144 on semiconductor wafer 100 can be bonded to conductive material 244 on semiconductor wafer 200 and polymer material 146 on semiconductor wafer 100 can be bonded to polymer material 246 on semiconductor wafer 200. In some embodiments, the alignment of semiconductor wafers 100 and 200 may be achieved by using an optical sensing method.
(23) Referring to
(24) Afterwards, stacking structure 300 is further heated to a higher temperature in a range from about 220 C. to about 380 C., such that conductive materials 144 and 244 are interconnected by thermocompression bonding and polymer materials 146 and 246 are fully cured. In some embodiments, the pressure for hybrid bonding is in a range from about 0.7 bar to about 10 bar. The hybrid bonding process may be performed in an inert environment, such as an environment filled with inert gas including N.sub.2, Ar, He, or combinations thereof.
(25) As shown in
(26) Compared to hybrid bonding involving other dielectric layers, semiconductor wafers 100 and 200 are bonded through polymer materials 146 and 246. Since the bonding of polymer materials 146 and 246 involves the reflowing of polymer materials 146 and 246, voids in polymer materials 146 and 246 are eliminated and bonding strength of semiconductor wafers 100 and 200 is improved.
(27) Referring to
(28) If thinning process 11 is performed before semiconductor wafers 100 and 200 are bonded, the thin semiconductor wafer 100 is easy to break during subsequent processes. However, if semiconductor wafers 100 and 200 are bonded firstly, as shown in
(29) Referring to
(30) After forming interconnect structure 500, one or more redistribution layers (RDLs) (not shown) may be formed over interconnect structure 500. For example, redistribution layers (RDLs) are embedded in a passivation layer. Interconnect structure 500, redistribution layers (RDLs) and TSVs 400 provide electrical interconnection. In addition, since TSVs 400 have a relatively low resistance, RC delay is reduced.
(31) In addition, other processes may also be performed to 3DIC stacking structure 300, and 3DIC stacking structure 300 may be diced to form individual chips afterwards.
(32)
(33) As shown in
(34) Because semiconductor wafer 200 will be thinned later to expose TSVs 600, TSVs 600 do not extend through the whole substrate 204 of semiconductor wafer 200. Therefore, TSVs 600 are designed to have a depth D.sub.2 which is smaller than original height H.sub.3 of semiconductor wafer 100.
(35) In some embodiments, semiconductor wafer 200 has a height H.sub.3 from a bottom surface 204b of semiconductor substrate 204 to a top surface of gate structure 209 in a range from about 17 m to about 100 m. In some embodiments, TSVs 600 have a width W.sub.3 in a range from about 0.3 m to about 10 m. In some embodiments, TSVs 600 have a depth D.sub.2 in a range from about 15 m to about 100 m. In some embodiments, TSVs 600 have an aspect ratio (D.sub.2/W.sub.3) in a range from about 5 to about 15. In some embodiments, depth D.sub.1 is the same as depth D.sub.2. In some other embodiments, depth D.sub.1 is different with depth D.sub.2
(36) Referring to
(37) Referring to
(38) Referring to
(39) An under bump metallization (UBM) layer 165 is formed on metal pad 162, and conductive element 166 (such as solder ball) is formed over UBM layer 165. UBM layer 165 may contain an adhesion layer and/or a wetting layer. In some embodiments, UBM layer 165 is made of titanium (Ti), titanium nitride (TiN), tantalum nitride (TaN), tantalum (Ta), or the like. In some embodiments, UBM layer 165 further includes a copper seed layer. In some embodiments, conductive element 166 is made of conductive materials with low resistivity, such as solder or solder alloy. Exemplary elements included in the solder alloy include Sn, Pb, Ag, Cu, Ni, Bi or combinations thereof.
(40) Interconnect structure 500 is electrically connected to another package (not shown) on the backside of semiconductor wafer 200 via TSVs 600, RDL structure 160 and conductive element 166.
(41) TSVs 400 and 600 individually provide different functions. Semiconductor wafer 100 is electrically connected to another package structure (not shown) via interconnect structure 500 and TSVs 400. Semiconductor wafer 200 is electrically connected to another package structure (not shown) via interconnect structure 500 and TSVs 600. TSVs 400 and 600 provide a fast conductive path to connect semiconductor wafer 100, semiconductor wafer 200, and/or other package structures, without the formation of complicated metal routings.
(42) Embodiments of mechanisms for forming a die stack are provided. Two semiconductor wafers are bonded together by hybrid bonding with metal-to-meal bonding and polymer-to-polymer bonding to form the die stack. TSVs are formed before the two semiconductor wafers are bonded. One or both of the semiconductor wafers are thinned to expose the TSVs after the semiconductor wafers are bonded. The bonded semiconductor wafers provides extra strength to reduce the risk of wafer breaking during a thinning process. In addition, polymer-to-polymer bonding is strong, and the polymer material is soft to provide a cushion to absorb the stress resulting from the TSVs.
(43) In some embodiments, a semiconductor device structure is provided. The semiconductor device includes a bonding structure formed between a first substrate and a second substrate. The bonding structure includes a first polymer bonded to a second polymer, and a first conductive material bonded to a second conductive material. The semiconductor device includes a first TSV formed in the first substrate and an interconnect structure formed over the first TSV. The first TSV is between the interconnect structure and the bonding structure.
(44) In some embodiments, a semiconductor device structure is provided. The semiconductor device includes a first metallization structure formed over a first substrate and a first bonding structure formed over the first metallization structure. The first bonding structure includes a first conductive material embedded in a first polymer material and a second bonding structure formed over a second substrate. The second bonding structure includes a second conductive material embedded in a second polymer material, the first conductive material is bonded to the second conductive material and the first polymer material is bonded to the second polymer material. The semiconductor device includes a first through substrate via (TSV) extending from a bottom surface of the first substrate to the first metallization structure, and the first metallization structure is between the first TSV and the first polymer material.
(45) In some embodiments, a semiconductor device structure is provided. The semiconductor device includes a first substrate bonded to a second substrate via a bonding structure, and the bonding structure includes a first polymer bonded to a second polymer, and a first diffusion barrier layer bonded to a second diffusion barrier layer. The semiconductor device also includes a first TSV extending from a bottom surface of the first substrate to a first metallization structure and a second TSV extending from a bottom surface of the second substrate to a second metallization structure over the second substrate. The second metallization structure is between the second diffusion barrier layer and the second TSV.
(46) Although embodiments of the present disclosure and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. For example, it will be readily understood by those skilled in the art that many of the features, functions, processes, and materials described herein may be varied while remaining within the scope of the present disclosure. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.