Substrate-free semiconductor device assemblies with multiple semiconductor devices and methods for making the same
11710702 · 2023-07-25
Assignee
Inventors
Cpc classification
H01L2221/68359
ELECTRICITY
H01L2224/73204
ELECTRICITY
H01L23/3142
ELECTRICITY
H01L21/4853
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L24/20
ELECTRICITY
H01L2224/96
ELECTRICITY
H01L2224/92225
ELECTRICITY
H01L2224/73204
ELECTRICITY
H01L2225/06513
ELECTRICITY
H01L2224/32225
ELECTRICITY
H01L2225/06517
ELECTRICITY
H01L23/5384
ELECTRICITY
H01L21/563
ELECTRICITY
H01L23/49816
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2224/32225
ELECTRICITY
H01L2225/06524
ELECTRICITY
H01L2924/00
ELECTRICITY
H01L2224/16227
ELECTRICITY
H01L2224/19
ELECTRICITY
H01L2224/92125
ELECTRICITY
H01L2924/00
ELECTRICITY
H01L2224/16237
ELECTRICITY
H01L2225/06541
ELECTRICITY
H01L2224/19
ELECTRICITY
H01L2225/06548
ELECTRICITY
H01L2224/96
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/81191
ELECTRICITY
H01L25/50
ELECTRICITY
H01L2224/16225
ELECTRICITY
H01L23/3128
ELECTRICITY
H01L2225/06565
ELECTRICITY
H01L23/5389
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2221/68368
ELECTRICITY
H01L24/19
ELECTRICITY
H01L2224/16225
ELECTRICITY
H01L2224/20
ELECTRICITY
H01L2221/68345
ELECTRICITY
H01L2225/06586
ELECTRICITY
H01L2224/92244
ELECTRICITY
H01L24/73
ELECTRICITY
International classification
H01L23/538
ELECTRICITY
H01L25/065
ELECTRICITY
H01L21/48
ELECTRICITY
H01L25/00
ELECTRICITY
H01L23/498
ELECTRICITY
Abstract
A semiconductor device assembly includes a first remote distribution layer (RDL), the first RDL comprising a lower outermost planar surface of the semiconductor device assembly; a first semiconductor die directly coupled to an upper surface of the first RDL by a first plurality of interconnects; a second RDL, the second RDL comprising an upper outermost planar surface of the semiconductor device assembly opposite the lower outermost planar surface; a second semiconductor die directly coupled to a lower surface of the second RDL by a second plurality of interconnects; an encapsulant material disposed between the first RDL and the second RDL and at least partially encapsulating the first and second semiconductor dies; and a third plurality of interconnects extending fully between and directly coupling the upper surface of the first RDL and the lower surface of the second RDL.
Claims
1. A semiconductor device assembly, comprising: a first remote distribution layer (RDL), the first RDL comprising a lower outermost planar surface of the semiconductor device assembly; a first semiconductor die directly coupled to an upper surface of the first RDL by a first plurality of interconnects; a second RDL, the second RDL comprising an upper outermost planar surface of the semiconductor device assembly opposite the lower outermost planar surface; a second semiconductor die directly coupled to a lower surface of the second RDL by a second plurality of interconnects; an encapsulant material disposed between the first RDL and the second RDL and at least partially encapsulating the first and second semiconductor dies; and a third plurality of interconnects extending fully between and directly coupling the upper surface of the first RDL and the lower surface of the second RDL, wherein the lower outermost planar surface comprises a dielectric material with a plurality of openings in which a corresponding plurality of bond pads are disposed, and wherein each of the plurality of bond pads is electrically connected to an interconnect of the first plurality of interconnects, an interconnect of the third plurality of interconnects, or both.
2. The semiconductor device assembly of claim 1, wherein the first semiconductor die has a first back surface opposite the first plurality of interconnects, the second semiconductor die has a second back surface opposite the second plurality of interconnects, and the first and second back surfaces are coupled by an adhesive.
3. The semiconductor device assembly of claim 1, wherein the second semiconductor die is electrically coupled to the first RDL by the second plurality of interconnects, the second RDL, and the third plurality of interconnects.
4. The semiconductor device assembly of claim 1, wherein the upper outermost planar surface comprises a dielectric material with no openings.
5. The semiconductor device assembly of claim 1, wherein each of the second plurality of interconnects is electrically connected to a corresponding interconnect of the third plurality of interconnects.
6. The semiconductor device assembly of claim 1, further comprising a layer of underfill material between the second semiconductor device and the second RDL.
7. The semiconductor device assembly of claim 1, wherein a lower surface of each of the first plurality of interconnects is co-planar with a lower surface of each of the third plurality of interconnects.
8. A method of making a semiconductor device assembly, comprising: forming a first remote distribution layer (RDL) comprising a plurality of external pads, a first plurality of internal pads and a second plurality of internal pads; disposing a first semiconductor device over the first RDL and electrically connecting a first plurality of die contacts of the first semiconductor device to the first plurality of internal pads with a first plurality of interconnects; forming a second plurality of interconnects on the second plurality of internal pads; disposing a second semiconductor device over the first semiconductor device; forming a third plurality of interconnects on a second plurality of die contacts of the second semiconductor device; encapsulating the first and second semiconductor devices and the second and third pluralities of interconnects with an encapsulant material; planarizing the encapsulant material to expose co-planar surfaces of the second and third pluralities of interconnects; and forming a second RDL over the encapsulant material and electrically connecting corresponding ones of the second and third pluralities of interconnects.
9. The method of claim 8, wherein forming the first RDL comprises forming a plurality of dielectric layers and a plurality of electrical connection features between the plurality of external pads and the first and second pluralities of internal pads.
10. The method of claim 9, wherein the first RDL is formed over a carrier wafer.
11. The method of claim 10, further comprising: removing the carrier wafer from the first RDL.
12. The method of claim 8, wherein disposing the second semiconductor device over the first semiconductor device comprises adhering a backside of the second semiconductor device to a backside of the first semiconductor device with a layer of adhesive.
13. The method of claim 8, wherein the second plurality of interconnects comprise copper pillars having a height greater than a combined height of the first and second semiconductor devices.
14. The method of claim 8, further comprising: forming a plurality of solder balls on the plurality of external pads.
15. The method of claim 8, further comprising: singulating the semiconductor device assembly from a plurality of other semiconductor device assemblies.
16. The method of claim 8, wherein the second RDL comprises an upper outermost planar surface of the semiconductor device assembly having a dielectric material with no openings.
17. The method of claim 8, further comprising: dispensing an underfill material between the first semiconductor device and the first RDL.
18. A semiconductor device assembly comprising: a first remote distribution layer (RDL), the first RDL comprising a lower outermost planar surface of the semiconductor device assembly; one or more face-down semiconductor dies coupled to the first RDL by a first plurality of interconnects; a second RDL, the second RDL comprising an upper outermost planar surface of the semiconductor device assembly opposite the lower outermost planar surface; one or more face-up semiconductor dies coupled to the second RDL by a second plurality of interconnects; an encapsulant material disposed between the first RDL and the second RDL and at least partially encapsulating the one or more first semiconductor dies and the one or more second semiconductor dies; and a third plurality of interconnects extending fully between and directly coupling the first RDL and the second RDL, wherein the lower outermost planar surface comprises a dielectric material with a plurality of openings in which a corresponding plurality of bond pads are disposed, and wherein each of the plurality of bond pads is electrically connected to an interconnect of the first plurality of interconnects, an interconnect of the third plurality of interconnects, or both.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(5) Specific details of several embodiments of semiconductor devices, and associated systems and methods, are described below. A person skilled in the relevant art will recognize that suitable stages of the methods described herein can be performed at the wafer level or at the die level. Therefore, depending upon the context in which it is used, the term “substrate” can refer to a wafer-level substrate or to a singulated, die-level substrate. Furthermore, unless the context indicates otherwise, structures disclosed herein can be formed using conventional semiconductor-manufacturing techniques. Materials can be deposited, for example, using chemical vapor deposition, physical vapor deposition, atomic layer deposition, plating, electroless plating, spin coating, and/or other suitable techniques. Similarly, materials can be removed, for example, using plasma etching, wet etching, chemical-mechanical planarization, or other suitable techniques.
(6) One approach to packaging semiconductor devices into an assembly includes electrically coupling a semiconductor device to an interposer or other pre-formed substrate that is configured to mate with the bond pads of external devices. A significant drawback to pre-formed substrates, however, is their thickness, which contributes significantly to the height (e.g., in the z-dimension) of the semiconductor packages that employ them. Other approaches to packaging semiconductor devices can instead include forming a redistribution layer (RDL) directly on a die (e.g., in a wafer level fan-out process (FOP)). The RDL can includes traces, lines and/or vias that connect the bond pads of a semiconductor device with RDL bond pads, which can in turn be configured to mate with the bond pads of external devices. In one such packaging approach, many semiconductor devices are mounted on a carrier (e.g., at the wafer or panel level) and encapsulated before the carrier is removed. Then an RDL can be formed directly on a front side (e.g., active surface) of the semiconductor devices using various well-known deposition and lithography techniques. Finally, an array of leads, ball-pads, or other types of electrical interconnects are mounted on bond pads of the RDL and the encapsulated semiconductor devices are singulated to form individual device assemblies.
(7) One drawback with the foregoing packaging technique is that it makes it difficult and costly to include multiple semiconductor dies in a single package. Accordingly, various embodiments of the present disclosure address this limitation by providing semiconductor device assemblies with upper and lower RDLs, each configured to couple with a respective die (or die stack), with the dies of each of the upper and lower RDL being arranged back-to-back, and the RDLs electrically connected by interconnects laterally spaced apart from the semiconductor devices.
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(9) Turning to
(10) Turning to
(11) As is illustrated in
(12) Turning to
(13) As is illustrated in
(14) Turning to
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(16) In accordance with one aspect of the present disclosure, the first and second semiconductor dies 1302 and 1304 can be memory dies, such as dynamic random access memory (DRAM) dies, NOT-AND (NAND) memory dies, NOT-OR (NOR) memory dies, magnetic random access memory (MRAM) dies, phase change memory (PCM) dies, ferroelectric random access memory (FeRAM) dies, static random access memory (SRAM) dies, or any combination thereof. In this regard, the first and second semiconductor dies 1302 and 1304 can be memory dies of a same kind (e.g., both NAND, both DRAM, etc.) or memory dies of different kinds (e.g., one DRAM and one NAND, etc.). In accordance with another aspect of the present disclosure, the first and second semiconductor dies 1302 and 1304 can be logic dies (e.g., controller dies, processor dies, etc.), or a mix of logic and memory dies (e.g., a memory controller die and a memory die controlled thereby).
(17) Although in the foregoing example embodiment semiconductor device assemblies have been illustrated and described as including two semiconductor devices, in other embodiments assemblies can be provided with additional semiconductor devices. For example, one or both of the first and second semiconductor devices illustrated in
(18) In another embodiment, rather than replacing the second semiconductor device 107 illustrated in
(19) In yet another embodiment, each of the first semiconductor device 105 in
(20) Although in the foregoing example embodiments, assemblies have been shown with a single die or a single stack of dies connected to each of the first and second RDLs, in other embodiments multiples dies and/or multiple stacks of dies can be arranged (e.g., side-by-side) on one or both of the first and second RDLs. Such an assembly can be fabricated in a similar fashion to the assembly 1300 illustrated in
(21) Any one of the semiconductor devices and semiconductor device assemblies described above with reference to
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(23) The devices discussed herein, including a memory device, may be formed on a semiconductor substrate or die, such as silicon, germanium, silicon-germanium alloy, gallium arsenide, gallium nitride, etc. In some cases, the substrate is a semiconductor wafer. In other cases, the substrate may be a silicon-on-insulator (SOI) substrate, such as silicon-on-glass (SOG) or silicon-on-sapphire (SOP), or epitaxial layers of semiconductor materials on another substrate. The conductivity of the substrate, or sub-regions of the substrate, may be controlled through doping using various chemical species including, but not limited to, phosphorous, boron, or arsenic. Doping may be performed during the initial formation or growth of the substrate, by ion-implantation, or by any other doping means.
(24) The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. Other examples and implementations are within the scope of the disclosure and appended claims. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.
(25) As used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of” or “one or more of”) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an exemplary step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on.”
(26) As used herein, the terms “vertical,” “lateral,” “upper,” “lower,” “above,” and “below” can refer to relative directions or positions of features in the semiconductor devices in view of the orientation shown in the Figures. For example, “upper” or “uppermost” can refer to a feature positioned closer to the top of a page than another feature. These terms, however, should be construed broadly to include semiconductor devices having other orientations, such as inverted or inclined orientations where top/bottom, over/under, above/below, up/down, and left/right can be interchanged depending on the orientation.
(27) It should be noted that the methods described above describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Furthermore, embodiments from two or more of the methods may be combined.
(28) From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the scope of the invention. Rather, in the foregoing description, numerous specific details are discussed to provide a thorough and enabling description for embodiments of the present technology. One skilled in the relevant art, however, will recognize that the disclosure can be practiced without one or more of the specific details. In other instances, well-known structures or operations often associated with memory systems and devices are not shown, or are not described in detail, to avoid obscuring other aspects of the technology. In general, it should be understood that various other devices, systems, and methods in addition to those specific embodiments disclosed herein may be within the scope of the present technology.