Semiconductor Devices and Methods of Manufacture Thereof
Semiconductor devices and methods of manufacture thereof are disclosed. In some embodiments, a semiconductor device includes a first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate, and a second semiconductor chip bonded to the first semiconductor chip. The second semiconductor chip includes a second substrate and a second conductive feature formed over the second substrate. A conductive plug is disposed through the first conductive feature and is coupled to the second conductive feature. The conductive plug includes a first portion disposed over the first conductive feature, the first portion having a first width, and a second portion disposed beneath or within the first conductive feature. The second portion has a second width. The first width is greater than the second width.
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This application relates to the following co-pending and commonly assigned patent application: Ser. No. 13/839,860, filed on Mar. 15, 2013, entitled, “Interconnect Structure and Method,” which application is hereby incorporated herein by reference in its entirety.
BACKGROUNDSemiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment, as examples. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon. The semiconductor industry continues to improve the integration density of various electronic components (e.g., transistors, diodes, resistors, capacitors, etc.) by continual reductions in minimum feature size, which allow more components to be integrated into a given area.
As semiconductor technologies further advance, stacked semiconductor devices have emerged as an effective alternative to further reduce the physical size of a semiconductor device. In a stacked semiconductor device, active circuits such as logic, memory, processor circuits and the like are fabricated on different semiconductor wafers. Two or more semiconductor wafers may be installed on top of one another to further reduce the form factor of the semiconductor device.
Two semiconductor wafers may be bonded together through suitable bonding techniques. Some commonly used bonding techniques for semiconductor wafers include direct bonding, chemically activated bonding, plasma activated bonding, anodic bonding, eutectic bonding, glass frit bonding, adhesive bonding, thermo-compressive bonding, reactive bonding and/or the like. After two semiconductor wafers are bonded together, the interface between two semiconductor wafers may provide an electrically conductive path between the stacked semiconductor wafers in some applications.
One advantageous feature of stacked semiconductor devices is that much higher density can be achieved by employing stacked semiconductor devices. Furthermore, stacked semiconductor devices can achieve smaller form factors, improved cost-effectiveness, increased performance, and lower power consumption.
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:
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTSThe making and using of some of the embodiments of the present disclosure are discussed in detail below. It should be appreciated, however, that the present disclosure provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the disclosure, and do not limit the scope of the disclosure.
Some embodiments of the present disclosure are related to novel methods of forming conductive plugs between conductive features of semiconductor wafers that are bonded together, and structures thereof.
Referring first to
The second semiconductor chip 110b includes a second substrate 102b and a second conductive feature 106b formed over the second substrate 102b. The second conductive feature 106b is formed in a second IMD 104b disposed over the second substrate 102b. The first conductive feature 106a is formed in a redistribution layer (RDL) 132b of the second IMD 104b in some embodiments. The second semiconductor chip 110b may include a plurality of second conductive features 106b in some embodiments.
The first and second IMDs 104a and 104b of the first semiconductor chip 110a and the second semiconductor chip 110b, respectively, may include a plurality of conductive features such as conductive lines 108a and 108b and vias (not shown) formed in a plurality of insulating material layers of the first and second IMDs 104a and 104b using damascene or subtractive etch techniques, as examples.
The first and second substrates 102a and 102b of the first semiconductor chip 110a and the second semiconductor chip 110b, respectively, each comprise a workpiece which may include a semiconductor substrate comprising silicon or other semiconductor materials and may be covered by an insulating layer, for example. The workpieces may also include other active components or circuits, not shown. The workpieces may comprise silicon oxide over single-crystal silicon, for example. The workpieces may include other conductive layers or other semiconductor elements, e.g., transistors, diodes, etc. Compound semiconductors, GaAs, InP, Si/Ge, or SiC, as examples, may be used in place of silicon. The workpieces may comprise a silicon-on-insulator (SOI) or a germanium-on-insulator (GOI) substrate, as examples.
In
A bottom anti-reflection coating (BARC) layer 112, also shown in
A patterned mask (not shown) such as a photoresist mask and/or the like may be formed over the BARC layer 112 using suitable deposition and photolithography techniques. A suitable etching process, such as a reactive ion etch (RIE) or other dry etch, an anisotropic wet etch, or any other suitable anisotropic etch or patterning process may be applied to the first substrate 102a of the first semiconductor chip 110a. As a result, a plurality of openings are formed in the BARC layer 112 and the first substrate 102a, as shown in
It should be noted that the first conductive features 106a and second conductive features 106b may be comprised of suitable metal materials such as copper in some embodiments, which has a different etching rate (selectivity) from the first substrate 102a and the insulating material layers of the first IMD 104a and the second IMD 104b. As such, the first conductive features 106a may function as a hard mask layer for the etching process of the first IMD 104a and the second IMD 104b. A selective etching process may be employed to etch the first IMD 104a and the second IMD 104b rapidly while etching only a portion of or a negligible amount of the first conductive features 106a. As shown in
The remaining mask 116 (see
Referring next to
Each conductive plug 120 may comprise three portions in some embodiments. A first portion extends from the second conductive features 106b to the hard mask layer formed by the first conductive features 106a. The first portion is of a width W1, as shown in
In embodiments wherein a top portion of the first conductive features 106a is removed during the etch process described for
After the conductive plug 120 formation, a dielectric layer 118 is formed on the semiconductor device 100 in accordance with some embodiments of the present disclosure, also shown in
An advantageous feature of the semiconductor device 100 comprising the stacked wafers having the conductive plugs 120 shown in
In some embodiments, the semiconductor device 100 includes a conductive plug 120 that is coupled between the first conductive feature 106a and the second conductive feature 106b. The conductive plug 120 is disposed through the first conductive feature 106a and is coupled to the second conductive feature 106b in some embodiments. For example, the conductive plug 120 passes through the first conductive feature 106a and ends at the second conductive feature 106b, in some embodiments.
In some embodiments, the conductive plug 120 includes a first portion disposed over the first conductive feature 106a, the first portion comprising a first width comprising dimension W3. The conductive plug 120 includes a second portion disposed beneath or within the first conductive feature 106a, the second portion comprising a second width comprising dimension W1. The first width comprising dimension W3 is greater than the second width comprising dimension W1. The first portion of the conductive plug 120 having the first width comprising dimension W3 is disposed within the first substrate 102a of the first semiconductor chip 110a in some embodiments. In some embodiments, the conductive plug 120 further comprises a third portion disposed between the first portion having the first width comprising dimension W3 and the first conductive feature 106a. The third portion of the conductive plugs 120 has a third width comprising a dimension W2, wherein the third width comprising dimension W2 is greater than the second width of the conductive plugs 120 comprising dimension W1, and wherein the third width comprising dimension W2 is less than the first width of the conductive plugs 120 comprising dimension W3.
Two conductive plugs 120 are shown in the figures; however, only one conductive plug 120 may be formed, or a plurality of conductive plugs 120 (e.g., three or more) may be formed within the semiconductor device 100. The conductive plugs 120 form vertical connections for the semiconductor device 100 between the first conductive features 106a and the second conductive features 106b. Likewise, only two semiconductor chips 110a and 110b are shown; alternatively, three or more semiconductor chips may be bonded together and connected together using conductive plugs 120 in accordance with some embodiments of the present disclosure.
The first conductive feature 106a comprises a hard mask for a formation of the second portion of the conductive plug 120 which has the second width comprising dimension W1 in some embodiments. The first conductive feature 106a comprises an opening therein, and the second portion of the conductive plug 120 having the second width comprising dimension W1 is disposed beneath the opening in the first conductive feature 106a in some embodiments. The first conductive feature 106a comprises a circular, oval, square, rectangular, or other shape in a top view in some embodiments, as described in the related patent application.
In accordance with some embodiments of the present disclosure, the first conductive feature 106a, the second conductive feature 106b, and the conductive plugs 120 comprise a conductive material such as W, Cu, AlCu, polysilicon, other conductive materials, or combinations or multiple layers thereof, as examples. Alternatively, the first conductive feature 106a, the second conductive feature 106b, and the conductive plugs 120 may comprise other materials.
In some embodiments, a portion of the conductive plugs 120 is disposed within the first conductive feature 106a or the second conductive feature 106b. For example, in
In the embodiment shown in
In the embodiments shown in
For example,
Thus, in accordance with some embodiments of the present disclosure, the first conductive feature 106a and/or the second conductive feature 106b may comprise a contact in a contact layer, a conductive line in a conductive line layer, or a portion of an RDL in an RDL layer of the first semiconductor chip 110a or the second semiconductor chip 110b, respectively. The first conductive feature 106a may comprise a conductive line in a bottom metallization layer of the first semiconductor chip 110a, in a top metallization layer of the first semiconductor chip 110a, or in a metallization layer disposed between a bottom metallization layer and a top metallization layer of the first semiconductor chip 110a. Likewise, the second conductive feature 106b may comprise a conductive line in a bottom metallization layer of the second semiconductor chip 110b, in a top metallization layer of the second semiconductor chip 110b, or in a metallization layer disposed between a bottom metallization layer and a top metallization layer of the second semiconductor chip 110b.
The conductive plugs 120 are disposed within the IMD 104a or 104b of the first semiconductor chip 110a and/or the second semiconductor chip 110b in accordance with some embodiments. For example, in
The first semiconductor chip 110a or the second semiconductor chip 110b comprises an application specific integrated circuit (ASIC) device or a system-on-a-chip (SOC) in some embodiments. Alternatively, the first semiconductor chip 110a or the second semiconductor chip 110b may comprise other types of devices and may be adapted to perform other functions. In some embodiments, the semiconductor device 100 comprises a complementary metal oxide semiconductor (CMOS) image sensor device. In some embodiments, the semiconductor device 100 comprises a backside illuminated imaging sensor that includes a semiconductor chip 110b comprising an ASIC device and a semiconductor chip 110a comprising a sensor device and/or SOC, as another example. Alternatively, the semiconductor device 100 may comprise other types of devices.
Some embodiments of the present disclosure include methods of manufacturing semiconductor devices 100 that include the conductive plugs 120, and also include semiconductor devices 100 that include the novel conductive plugs 120 described herein.
Advantages of some embodiments of the disclosure include providing novel methods of forming interconnects for two or more semiconductor wafers or chips that have been bonded together. The conductive plugs 120 may advantageously be used to interconnect between any conductive material layers of the semiconductive chips. The conductive plugs 120 comprise through-vias that provide vertical electrical connections for semiconductor devices 100. The conductive plugs 120 and also the conductive features 106a and 106b may be comprised of a variety of conductive materials. Furthermore, the novel semiconductor device 100 structures and designs are easily implementable in manufacturing process flows.
In accordance with some embodiments of the present disclosure, a semiconductor device includes a first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate, and a second semiconductor chip bonded to the first semiconductor chip. The second semiconductor chip includes a second substrate and a second conductive feature formed over the second substrate. A conductive plug is disposed through the first conductive feature and is coupled to the second conductive feature. The conductive plug includes a first portion disposed over the first conductive feature, the first portion having a first width, and a second portion disposed beneath or within the first conductive feature. The second portion has a second width. The first width is greater than the second width.
In accordance with other embodiments, a semiconductor device includes a first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate. The first conductive feature is disposed in a contact layer, a conductive line layer, or an RDL of the first semiconductor chip. The semiconductor device includes a second semiconductor chip bonded to the first semiconductor chip, the second semiconductor chip including a second substrate and a second conductive feature formed over the second substrate. The second conductive feature is disposed in a contact layer, a conductive line layer, or an RDL of the second semiconductor chip. A conductive plug is disposed through the first conductive feature and is coupled to the second conductive feature. The conductive plug includes a first portion disposed over the first conductive feature, the first portion comprising a first width, and a second portion disposed beneath or within the first conductive feature, the second portion comprising a second width. The first width is greater than the second width. The conductive plug includes a third portion disposed between the first portion and the first conductive feature, the third portion comprising a third width. The third width is greater than the second width and less than the first width.
In accordance with other embodiments, a method of manufacturing a semiconductor device includes providing a first semiconductor chip and a second semiconductor chip bonded to the first semiconductor chip. The first semiconductor chip includes a first substrate and a first conductive feature formed over the first substrate. The second semiconductor chip includes a second substrate and a second conductive feature formed over the second substrate. The method includes forming a conductive plug that is disposed through the first conductive feature and coupled to the second conductive feature. The conductive plug comprises a first portion disposed over the first conductive feature, the first portion comprising a first width. The conductive plug further comprises a second portion disposed beneath or within the first conductive feature, the second portion comprising a second width. The first width is greater than the second width.
Although some 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.
Claims
1. A semiconductor device, comprising:
- a first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate;
- a second semiconductor chip bonded to the first semiconductor chip, the second semiconductor chip including a second substrate and a second conductive feature formed over the second substrate; and
- a conductive plug disposed through the first conductive feature and coupled to the second conductive feature, wherein the conductive plug comprises: a first portion disposed over the first conductive feature, the first portion comprising a first width; and a second portion disposed beneath or within the first conductive feature, the second portion comprising a second width, wherein the first width is greater than the second width, and wherein the first conductive feature comprises a hard mask for a formation of the second portion of the conductive plug.
2. The semiconductor device according to claim 1, wherein the conductive plug further comprises a third portion disposed between the first portion and the first conductive feature, the third portion comprising a third width, and wherein the third width is greater than the second width and less than the first width.
3. (canceled)
4. The semiconductor device according to claim 1, wherein the first conductive feature or the second conductive feature comprises a contact, a conductive line, or a portion of a redistribution layer (RDL).
5. The semiconductor device according to claim 1, wherein the first conductive feature comprises an opening therein, and wherein the second portion of the conductive plug is disposed beneath the opening in the first conductive feature.
6. The semiconductor device according to claim 1, wherein the first conductive feature comprises a conductive line in a bottom metallization layer of the first semiconductor chip, a top metallization layer of the first semiconductor chip, or a metallization layer disposed between a bottom metallization layer and a top metallization layer of the first semiconductor chip.
7. The semiconductor device according to claim 1, wherein the second conductive feature comprises a conductive line in a bottom metallization layer of the second semiconductor chip, a top metallization layer of the second semiconductor chip, or a metallization layer disposed between a bottom metallization layer and a top metallization layer of the second semiconductor chip.
8. A semiconductor device, comprising:
- a first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate, the first conductive feature being disposed in a contact layer, a conductive line layer, or a redistribution layer (RDL) of the first semiconductor chip;
- a second semiconductor chip bonded to the first semiconductor chip, the second semiconductor chip including a second substrate and a second conductive feature formed over the second substrate, the second conductive feature being disposed in a contact layer, a conductive line layer, or an RDL of the second semiconductor chip; and
- a conductive plug disposed through the first conductive feature and coupled to the second conductive feature, wherein the conductive plug comprises: a first portion disposed over the first conductive feature, the first portion comprising a first width; a second portion disposed beneath or within the first conductive feature, the second portion comprising a second width, the first width being greater than the second width; and a third portion disposed between the first portion and the first conductive feature, the third portion comprising a third width, wherein the third width is greater than the second width and less than the first width.
9. The semiconductor device according to claim 8, wherein the first semiconductor chip or the second semiconductor chip comprises an application specific integrated circuit (ASIC) device or a system-on-a-chip (SOC).
10. The semiconductor device according to claim 8, wherein the semiconductor device comprises a complementary metal oxide semiconductor (CMOS) image sensor device.
11. The semiconductor device according to claim 8, wherein the conductive plug is disposed within an inter-metal dielectric (IMD) of the first semiconductor chip or the second semiconductor chip.
12. The semiconductor device according to claim 8, wherein the first conductive feature, the second conductive feature, or the conductive plug comprises a material selected from the group consisting essentially of W, Cu, AlCu, polysilicon, and combinations thereof.
13. The semiconductor device according to claim 8, wherein the first portion of the conductive plug is disposed within the first substrate of the first semiconductor chip.
14. The semiconductor device according to claim 8, wherein a portion of the conductive plug is disposed within the first conductive feature or the second conductive feature.
15. A method of manufacturing a semiconductor device, the method comprising:
- providing a first semiconductor chip and a second semiconductor chip bonded to the first semiconductor chip, the first semiconductor chip including a first substrate and a first conductive feature formed over the first substrate, the second semiconductor chip including a second substrate and a second conductive feature formed over the second substrate; and
- forming a conductive plug disposed through the first conductive feature and coupled to the second conductive feature, wherein the conductive plug comprises a first portion disposed over the first conductive feature, the first portion comprising a first width, and wherein the conductive plug further comprises a second portion disposed beneath or within the first conductive feature, the second portion comprising a second width, wherein the first width is greater than the second width, and wherein forming the second portion of the conductive plug comprises using the first conductive feature as a hard mask.
16. (canceled)
17. The method according to claim 15, wherein the first conductive feature comprises a contact, a conductive line, or a portion of a redistribution layer (RDL).
18. The method according to claim 15, wherein the second conductive feature comprises a contact, a conductive line, or a portion of a redistribution layer (RDL).
19. The method according to claim 15, wherein the first conductive feature, the second conductive feature, or the conductive plug comprises a material selected from the group consisting essentially of W, Cu, AlCu, polysilicon, and combinations thereof.
20. The method according to claim 15, wherein forming the conductive plug further comprises forming a conductive plug including a third portion disposed between the first portion and the first conductive feature, the third portion comprising a third width, and wherein the third width is greater than the second width and less than the first width.
21. The method according to claim 15, wherein forming the conductive plug comprises using a single mask pattern for forming the first portion and the second portion.
22. The method according to claim 15, wherein forming the conductive plug comprises forming a recess in a top surface of the first conductive feature.
Type: Application
Filed: Dec 26, 2013
Publication Date: Jul 2, 2015
Applicant: Taiwan Semiconductor Manufacturing Company, Ltd. (Hsin-Chu)
Inventors: Shu-Ting Tsai (Kaohsiung City), Dun-Nian Yaung (Taipei City), Jen-Cheng Liu (Hsin-Chu), Szu-Ying Chen (Toufen Township), U-Ting Chen (Wanluan Township)
Application Number: 14/141,000