The present disclosure relates to the technic field of semiconductors, in particular, to a chip packaging structure and method.
With the miniaturization of electronic products, requirement to chip volumes of various electronic products is increasingly high. However, restricted to the bottleneck of the manufacturing process of the chip itself, currently, it becomes increasingly difficult to further reduce the volume of chips with the desire to meet chip performance. Therefore, new heterogeneous integrated chip packaging will become one of the important solutions for miniaturized electronic devices. The heterogeneous chip packaging is capable of packaging a plurality of dies or chiplets of different materials into a novel system-on-a-chip (SOC).
In the heterogeneous chip packaging technology, two-dimensional packaging is to arrange a plurality of chips on a same packaging substrate for packaging, that is, a plurality of chips are on one plane; while for the three-dimensional packaging, some chips may be overlaid for packaging, that is, some chips are not on the same plane. The three-dimensional packaging may render a smaller planar area than the two-dimensional packaging, but the difficulty of the three-dimensional packaging is also higher.
Currently, a three-dimensional integrated circuit packaging process mainly adopts the wafer-to-wafer packaging based on face-to-back (or front-to-back), and such packaging form is applicable to a wafer level packaging technology. However, this technology cannot achieve three-dimensional heterogeneous packaging of dies of different materials and types.
The present disclosure provides a chip packaging structure, including:
a first chip, wherein the first chip comprises a front surface and a back surface, the front surface of the first chip is a functional surface having a transistor, the back surface of the first chip is a non-functional surface, the front surface of the first chip comprises a plurality of pins, and the plurality of pins on the front surface of the first chip may be pins disposed on a first redistribution layer on the front surface of the first chip or pin pads directly formed on the front surface of the first chip;
a second chip, wherein the second chip comprises a front surface and a back surface, the front surface of the second chip is a functional surface, the back surface of the second chip is a non-functional surface, and the front surface of the second chip is provided with a second redistribution layer;
the back surface of the second chip is bonded to the back surface of the first chip;
an encapsulating material, wherein the encapsulating material wraps the first chip and the second chip;
a plurality of through holes, wherein the plurality of through holes include: a first through hole penetrating from a part of the pins on the front surface of the first chip to the second redistribution layer through the first chip and the second chip, and/or a second through hole penetrating from the first redistribution layer to the back surface of the second chip through the encapsulating material, and a third through-hole penetrating from the back surface of the second chip to the second redistribution layer through the second chip; and
the plurality of through holes are filled with a conductive material, and a part of the pins on the front surface of the first chip and/or the pins on the first redistribution layer are electrically connected with a part of the pins on the second redistribution layer through the conductive material.
The present disclosure further provides a chip packaging method, wherein the method comprises:
providing a first chip, wherein the first chip comprises a front surface and a back surface, the front surface of the first chip is a functional surface having a transistor, the back surface of the first chip is a non-functional surface, the front surface of the first chip comprises a plurality of pins, the plurality of pins on the front surface of the first chip are pins disposed on a first redistribution layer on the front surface of the first chip or pin pads directly formed on the front surface of the first chip;
providing a second chip, wherein the second chip comprises a front surface and a back surface, the front surface of the second chip is a functional surface, and the back surface of the second chip is a non-functional surface;
providing a temporary carrier board;
first bonding the front surface of the second chip to the temporary carrier board, and then bonding the back surface of the first chip to the back surface of the second chip, or first bonding the back surface of the first chip to the back surface of the second chip, and then bonding the front surface of the second chip to the temporary carrier board;
wrapping the first chip and the second chip with an encapsulating material, and removing the temporary carrier board;
forming, after forming the second redistribution layer on the front surface of the second chip, a first through hole penetrating from the second redistribution layer to a part of the pins on the front surface of the first chip and formed with an insulation layer and a conductive material; or forming, after forming the first through hole penetrating from the front surface of the second chip to a part of the pins on the front surface of the first chip and formed with the insulation layer and the conductive material, the second redistribution layer on the front surface of the second chip, so that a part of the pins on the front surface of the first chip are electrically connected with a part of the pins on the second redistribution layer through the conductive material in the first through hole; and
forming a pad layer and a solder ball on the second redistribution layer.
The present disclosure further provides a chip packaging method, wherein the method comprises:
providing a first chip, wherein the first chip comprises a front surface and a back surface, the front surface of the first chip is a functional surface having a transistor, the back surface of the first chip is a non-functional surface, the front surface of the first chip comprises a plurality of pins of pin pads directly formed on the front surface of the first chip;
providing a second chip, wherein the second chip comprises a front surface and a back surface, the front surface of the second chip is a functional surface, the back surface of the second chip is a non-functional surface, and a part of the region on the back surface of the second chip is formed with an intermediate redistribution layer;
providing a temporary carrier board;
first bonding the front surface of the second chip to the temporary carrier board, and then bonding the back surface of the first chip to the back surface of the second chip; or first bonding the back surface of the first chip to the back surface of the second chip, and then bonding the front surface of the second chip to the temporary carrier board;
wrapping the first chip and the second chip with an encapsulating material, and removing the temporary carrier board;
forming a first redistribution layer on the encapsulating material on the front surface of the first chip, forming a second redistribution layer on the front surface of the second chip, then forming a second through hole penetrating from the first redistribution layer to the intermediate redistribution layer through the encapsulating material and filled with the insulation layer and the conductive material, and forming a third through hole penetrating from the second redistribution layer to the intermediate redistribution layer and filled with the insulation layer and the conductive material; or first forming a second through hole penetrating from the first redistribution layer to the intermediate redistribution layer through the encapsulating material and filled with the insulation layer and the conductive material, and forming a third through hole penetrating from the second redistribution layer to the intermediate redistribution layer and filled with the insulation layer and the conductive material, then forming the first redistribution layer on the encapsulating material on the front surface of the first chip, and forming the second redistribution layer on the front surface of the second chip, so that a part of the pins on the first redistribution layer are electrically connected with a part of the pins on the second redistribution layer through the conductive material in the second through hole, the intermediate redistribution layer, and the conductive material in the third through hole; and
forming a pad layer and a solder ball on the second redistribution layer.
For the chip packaging structure and method provided in the present disclosure, in the solution provided in the present embodiment, before bonding the chips, a through silicon via TSV may not need to be formed in advance on the chips, therefore, the requirement to the alignment accuracy of the chips can be reduced, and the process difficulty can be reduced. In addition, as the back-to-back packaging process is adopted, the heat dissipation efficiency of the chips can be improved, and the problem of circuit breakage due to materials with different expansion coefficients present between the chips can be avoided.
In order to more clearly illustrate technical solutions of embodiments of the present disclosure, accompanying drawings which need to be used in the embodiments will be introduced briefly below, and it should be understood that the accompanying drawings below merely show some embodiments of the present disclosure, therefore, they should not be considered as limitation on the scope, and those ordinarily skilled in the art still could obtain other relevant accompanying drawings according to these accompanying drawings, without any inventive effort.
In order to make objects, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely below in conjunction with accompanying drawings in the embodiments of the present disclosure, and apparently, the embodiments described are some but not all embodiments of the present disclosure. Generally, components in the embodiments of the present disclosure, as described and shown in the accompanying drawings herein, may be arranged and designed in various different configurations.
Therefore, the following detailed description of the embodiments of the present disclosure provided in the accompanying drawings is not intended to limit the scope of the present disclosure claimed, but merely represents chosen embodiments of the present disclosure. All of other embodiments obtained by those ordinarily skilled in the art based on the embodiments of the present disclosure without any inventive effort shall fall within the scope of protection of the present disclosure.
It should be noted that similar numerals and letters represent similar items in the following accompanying drawings, therefore, once a certain item is defined in one accompanying drawing, it is not needed to be further defined or explained in subsequent accompanying drawings.
In the description of the present disclosure, it should be indicated that orientation or positional relationships indicated by terms such as “center”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “inner”, and “outer” are based on orientation or positional relationships as shown in the accompanying drawings, or orientation or positional relationships of a product of the present disclosure conventionally placed when in use, merely for facilitating describing the present disclosure and simplifying the description, rather than indicating or suggesting that related devices or elements have to be in the specific orientation, or configured or operated in a specific orientation, therefore, they should not be construed as limiting the present disclosure. Besides, terms such as “first”, “second”, and “third” are merely for distinctive description, but should not be construed as indicating or implying relative importance.
Moreover, terms such as “horizontal”, “vertical”, and “pendulous” do not mean that a component is required to be absolutely horizontal or pendulous, but mean that the component can be slightly inclined. For example, by “horizontal” it merely means that a structure is more horizontal in comparison with “vertical”, rather than being completely horizontal, while the structure can be slightly inclined.
In some existing three-dimensional packaging technologies, a face-to-back packaging structure is commonly used. Referring to
Such face-to-back packaging structure is generally applicable to wafer-level packaging, for example, referring to
In some other existing three-dimensional packaging technologies, a face-to-face packaging structure is also adopted. Referring to
Such face-to-face packaging structure is generally applicable to die-to-die packaging process or die-to-wafer packaging process. For example, referring to
The face-to-face packaging structure still has very high positioning requirement to relative positions of the chips and the wafer. In addition, since the circuit positions of two chips are quite close in distance, if the circuit power consumption is very high, the heat dissipation problem will be hard to solve. If the heat dissipation is relatively poor, and if the filling material between the chip A and the chip B and the soldering tin have different coefficients of thermal expansion, the circuit may be broken. Meanwhile, such packaging will consume the area of the pin led out of the chip, thereby causing too high density of distribution of the pin and leading to crosstalk and integrity problems of electrical signals.
Based on research on the above problems, the present embodiment provides a three-dimensional heterogeneous packaging structure and method with more efficient heat dissipation and more flexible packaging mode. The solutions provided in the embodiment are described in detail below.
Referring to
The first chip 100 includes a front surface and a back surface, the front surface of the first chip 100 is a functional surface having a transistor(s), and the back surface of the first chip 100 is a non-functional surface. The front surface of the first chip 100 includes a plurality of pins, and the plurality of pins on the front surface of the first chip 100 may be pin pads directly formed on the front surface of the first chip 100, as shown in
The second chip 200 includes a front surface and a back surface, the front surface of the second chip 200 is a functional surface, the back surface of the second chip 200 is a non-functional surface, and the front surface of the second chip 200 is provided with a second redistribution layer 210. In the above, the front surface of the second chip 200 may be provided with an insulation material layer, and the second redistribution layer 210 is formed on the insulation material layer, and is electrically connected with pins on the second chip 200 through via holes on the insulation material layer.
In the present embodiment, the back surface of the second chip 200 is bonded to the back surface of the first chip 100. In a possible implementation, the back surface of the first chip 100 and the back surface of the second chip 200 may be bonded together by a binding material 400. In another possible implementation, the back surfaces of the first chip 100 and the second chip 200 may be made of the same material, such as metal copper, silicon, silicon dioxide. The back surface of the first chip 100 and the back surface of the second chip 200 are directly bonded together by grinding them to a certain degree of smoothness, and as the back surfaces of the two chips are of the same material and have a relatively high degree of smoothness, the back surfaces of the two chips can be bonded together through an interaction force between molecules of the same material.
Compared with the solution in which the filling material between the two chips and the soldering tin has different coefficients of thermal expansion in the face-to-face packaging, in the back-to-back packaging manner adopted in the present embodiment, there are substantially no substances with different expansion coefficients between the two bonded chips, thereby circuit breakage due to different expansion coefficients may be effectively avoided when the temperature is relatively high.
The encapsulating material 600 wraps the first chip 100 and the second chip 200. In the above, the encapsulating material 600 is a dielectric material, such as epoxy resin.
Referring again to
Referring again to
The plurality of through holes are filled with a conductive material, and a part of the pins on the front surface of the first chip 100 and/or the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material.
It should be noted that, in the present embodiment, an insulation layer is formed on an inner wall of the through holes penetrating the first chip 100 or the second chip 200, and the insulation layer electrically isolates the conductive material in the through holes from the first chip 100 or the second chip 200. In other words, in the present embodiment, in the plurality of through holes, an insulation layer is formed on the inner wall of the TSV hole.
It should also be noted that, in the chip packaging structure provided in the present embodiment, the number of the first through holes 810, the second through holes 820, and the third through holes 830 is not limited to the number shown in
In the present embodiment, the second redistribution layer 210 on the second chip 200 may serve as a redistribution layer of the entire packaging structure, and the second redistribution layer 210 may further be provided thereon with a pad layer and solder balls 230 for connection with other electronic circuit structures.
Based on the above designs, in the solution provided in the present embodiment, before bonding the chips, the TSV hole may not need to be formed in advance on the chips, thereby reducing the requirement to the alignment accuracy of the chips, and reducing the process difficulty. In addition, as the back-to-back packaging process is adopted, the heat dissipation efficiency of the chips can be improved, and the problem of circuit IC breakage due to materials with different expansion coefficients present between the chips can be avoided.
Optionally, in some possible implementations, an area of the second redistribution layer 210 is greater than the front surface of the second chip 200, and/or an area of the first redistribution layer 110 is greater than the front surface of the first chip 100. In other words, in the present embodiment, at least one of the first chip 100 and the second chip 200 may adopt a fan-out packaging structure, and at least one of the first redistribution layer 110 and the second redistribution layer 210 may be a fan-out redistribution layer.
Optionally, referring to
Optionally, referring to
A front surface of the third chip 300 is a functional surface, a back surface of the third chip 300 is a non-functional surface, the front surface of the third chip 300 includes a plurality of pins, the plurality of pins on the front surface of the third chip 300 may be pins disposed on a third redistribution layer 310 on the front surface of the third chip 300 or pin pads directly formed on the front surface of the third chip 300, and the front surface of the third chip 300 faces toward the front surface of the first chip 100.
In one example, a part of the pins (for example, a pin 311 shown in
In another example, a part of the pins on the front surface of the third chip 300 are corresponding to positions not covered by the second chip 200. The plurality of through holes further include a fifth through hole(s) 850, the fifth through hole 850 penetrates to a part of the pins on the front surface of the third chip 300 through the second chip 200 or the first chip 100, and the fifth through hole 850 is filled with the conductive material. In the above, a part of the pins on the second redistribution layer 210 are electrically connected with a part of the pins (a pin 312 as shown in
Based on the above design, in the solution provided in the present embodiment, in addition to the first chip 100 and the second chip 200, more chips may be stacked in the vertical direction, thereby further improving the integration degree of the chip packaging structure.
Further, in a possible implementation, the encapsulating material 600 may wrap only the first chip 100 and the second chip 200, but does not wrap the third chip 300, as shown in
Optionally, in some implementations, the first redistribution layer 110 and/or the second redistribution layer 210 may be of a multi-layer redistribution layer structure, the multi-layer redistribution layer structure includes a plurality of sub-redistribution layers, and the plurality of sub-redistribution layers may transmit signals relatively independent of each other, and may be electrically connected to each other at certain positions.
Referring to
Step S111: providing a first chip 100, wherein the first chip 100 includes a front surface and a back surface, the front surface of the first chip 100 is a functional surface having a transistor(s), the back surface of the first chip 100 is a non-functional surface, the front surface of the first chip 100 includes a plurality of pins, the plurality of pins on the front surface of the first chip 100 may be pins disposed on a first redistribution layer 110 on the front surface of the first chip 100 or pin pads directly formed on the front surface of the first chip 100.
Referring to
Step S112, providing a second chip 200, wherein the second chip 200 includes a front surface and a back surface, the front surface of the second chip 200 is a functional surface, and the back surface of the second chip 200 is a non-functional surface.
Step S113, providing a temporary carrier board 500.
In the present embodiment, the temporary carrier board 500 in step S113 may be a glass carrier board.
Step S114: first bonding the front surface of the second chip 200 to the temporary carrier board 500, and then bonding the back surface of the first chip 100 to the back surface of the second chip 200; or first bonding the back surface of the first chip 100 to the back surface of the second chip 200, and then bonding the front surface of the second chip 200 to the temporary carrier board 500.
In the present embodiment, the back surface of the first chip 100 and the back surface of the second chip 200 can be bonded together by a binding material 400, as shown in
Step S115, wrapping the first chip 100 and the second chip 200 with an encapsulating material 600, and removing the temporary carrier board 500.
Referring to
Step S116, forming, after forming the second redistribution layer 210 on the front surface of the second chip 200, first through holes 810 penetrating from the second redistribution layer 210 to a part of the pins on the front surface of the first chip 100 and filled with a conductive material; or forming, after forming the first through holes 810 penetrating from the front surface of the second chip 200 to a part of the pins on the front surface of the first chip 100 and filled with the conductive material, the second redistribution layer 210 on the front surface of the second chip 200, so that a part of the pins on the front surface of the first chip 100 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the first through holes 810.
Optionally, in a first possible implementation, in step S116, the second redistribution layer 210 may be first formed on the front surface of the second chip 200, as shown in
In a second possible implementation, in step S116, the first through holes 810 may be formed first and the conductive material is filled in the above first through holes 810, as shown in
It should be noted that, in the present embodiment, before filling the conductive material into the first through hole 810, an insulation material needs to be first covered on an inner wall of the through hole, and then the conductive material is filled into the first through hole 810, so as to prevent the conductive material from being in direct electrical contact with a silicon material inside the first chip 100 or the second chip 200.
Step S117, forming a pad layer and solder balls 230 on the second redistribution layer 210.
Optionally, in some other possible embodiments, it is also feasible that the second redistribution layer 210 is formed on the second chip 200 in advance, that is, the second chip 200 formed with the second redistribution layer 210 in advance is provided, and then steps such as bonding the two chips, forming the first through holes 810, and filling the conductive material are carried out.
Based on the above design, compared with the prior art solution in which TSV through holes need to be formed on the chips first, then the conductive patterns or solder points formed in advance are accurately aligned with the TSV through holes, in the chip packaging method provided in the present embodiment, it is feasible that the TSV through holes and the conductive patterns do not need to be formed in advance on the first chip 100 or the second chip 200, thus, the need for alignment accuracy of chips can be reduced, and the process difficulty is reduced.
Optionally, referring to
Step S121: providing a third chip 300, wherein the third chip 300 includes a front surface and a back surface, the front surface of the third chip 300 is a functional surface, the back surface of the third chip 300 is a non-functional surface, the front surface of the third chip 300 includes a plurality of pins, the plurality of pins on the front surface of the third chip 300 may be pins disposed on the third redistribution layer 310 on the front surface of the third chip 300 or pin pads directly formed on the front surface of the third chip 300.
Step S122, removing, after wrapping the first chip 100 and the second chip 200 with an encapsulating material 600, at least a part of the front surface of the first chip 100 exposed by the encapsulating material 600 on the front surface of the first chip 100.
Step S123, bonding a part of the pins on the front surface of the third chip 300 and a part of the pins on the front surface of the first chip 100 by a bonding material, so that a part of the pins on the front surface of the third chip 300 are electrically connected with a part of the pins on the front surface of the first chip 100.
For example, referring to
Optionally, referring to
Step S124: providing a third chip 300, wherein the third chip 300 includes a front surface and a back surface, the front surface of the third chip 300 is a functional surface, the back surface of the third chip 300 is a non-functional surface, the front surface of the third chip 300 includes a plurality of pins, the plurality of pins on the front surface of the third chip 300 may be pins disposed on the third redistribution layer 310 on the front surface of the third chip 300 or pin pads directly formed on the front surface of the third chip 300.
Step S125, forming, after wrapping the first chip 100 and the second chip 200 with the encapsulating material 600, a fifth through hole(s) 850 penetrating from the encapsulating material 600 to the second redistribution layer 210 and filled with the insulation layer and conductive material.
Step S126: bonding the front surface of the third chip 300 to the side of the encapsulating material 600 close to the front surface of the first chip 100, so that a part of the pins on the third chip 300 are in electrical contact with the conductive material in the fifth through hole 850, and accordingly a part of the pins on the front surface of the third chip 300 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the fifth through hole 850.
For example, in the present embodiment, the third redistribution layer 310 may include a pin 312 for electrical contact with the second redistribution layer 210. Referring to
It should be noted that, in the present embodiment, the third chip 300 may only have the pin 311 or the pin 312, and may simultaneously have the pin 311 and the pin 312, as shown in
Optionally, after bonding the third chip 300, the method may further include wrapping the third chip 300 with the encapsulating material 600.
Optionally, in the present embodiment, the method may further include forming a fourth through hole(s) 840 and filling the fourth through hole 840 with the conductive material, wherein the fourth through hole 840 penetrates from the first redistribution layer 110 to the second redistribution layer 210 through the encapsulating material 600, and a part of the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the fourth through hole 840.
Referring to
Step S211: providing a first chip 100, wherein the first chip 100 includes a front surface and a back surface, the front surface of the first chip 100 is a functional surface having a transistor(s), the back surface of the first chip 100 is a non-functional surface, the front surface of the first chip 100 includes a plurality of pins of pin pads directly formed on the front surface of the first chip 100.
In the present embodiment, the first chip 100 may be provided first, and a redistribution layer is formed on the front surface of the first chip 100, for example, a wafer on which the first chip 100 is located is first fixed on a temporary carrier board 500, and a back surface of the wafer is connected with the carrier board. Then, a metal layer or a redistribution layer is fabricated and distributed on a front surface of the wafer. In the above, the redistribution layer may be a redistribution layer. The wafer is then cut to obtain a single such first chip 100.
Step S212, providing a second chip 200, wherein the second chip 200 includes a front surface and a back surface, the front surface of the second chip 200 is a functional surface, the back surface of the second chip 200 is a non-functional surface, and a part of the region on the back surface of the second chip 200 is formed with an intermediate redistribution layer 220.
Referring to
Step S213, providing a temporary carrier board 500.
Step S214: first bonding the front surface of the second chip 200 to the temporary carrier board 500, and then bonding the back surface of the first chip 100 to the back surface of the second chip 200; or first bonding the back surface of the first chip 100 to the back surface of the second chip 200, and then bonding the front surface of the second chip 200 to the temporary carrier board 500.
In the present embodiment, the back surface of the first chip 100 and the back surface of the second chip 200 can be bonded together by a binding material 400, as shown in
Step S215, wrapping the first chip 100 and the second chip 200 with an encapsulating material 600, and removing the temporary carrier board 500.
Referring to
Step S216, forming a first redistribution layer 110 on the encapsulating material 600 on the front surface of the first chip 100, forming a second redistribution layer 210 on the front surface of the second chip 200, then forming a second through hole(s) 820 penetrating from the first redistribution layer 110 to the intermediate redistribution layer 220 through the encapsulating material 600 and filled with the insulation layer and the conductive material, and forming a third through hole(s) 830 penetrating from the second redistribution layer 210 to the intermediate redistribution layer 220 and filled with the insulation layer and the conductive material; or first forming a second through hole(s) 820 penetrating from the first redistribution layer 110 to the intermediate redistribution layer 220 through the encapsulating material 600 and filled with the insulation layer and the conductive material, and forming a third through hole(s) 830 penetrating from the second redistribution layer 210 to the intermediate redistribution layer 220 and filled with the insulation layer and the conductive material, then forming the first redistribution layer 110 on the encapsulating material 600 on the front surface of the first chip 100, and forming the second redistribution layer 210 on the front surface of the second chip 200, so that a part of the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the second through hole 820, the intermediate redistribution layer 220, and the conductive material in the third through hole 830.
Optionally, in a first possible implementation, in step S216, the first redistribution layer 110 may be first formed on the encapsulating material 600 on the front surface of the first chip 100, and the second redistribution layer 210 may be formed on the front surface of the second chip 200, as shown in
Then, a second through hole 820 penetrating from the first redistribution layer 110 to the intermediate redistribution layer 220 through the encapsulating material 600 and filled with the insulation layer and the conductive material is formed, and a third through hole 830 penetrating from the second redistribution layer 210 to the intermediate redistribution layer 220 and filled with the insulation layer and the conductive material is formed, as shown in
Next, the conductive material is filled in the second through hole 820 and the third through hole 830, so that a part of the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the second through hole 820, the intermediate redistribution layer 220, and the conductive material in the third through hole 830, as shown in
Optionally, in a second possible implementation, in step S216, it is also feasible that the second through hole 820 penetrating from the first redistribution layer 110 to the intermediate redistribution layer 220 through the encapsulating material 600 and filled with the insulation layer and the conductive material is formed first, and the third through hole 830 penetrating from the second redistribution layer 210 to the intermediate redistribution layer 220 and filled with the insulation layer and the conductive material is formed, as shown in
Then, a first redistribution layer 110 is formed on the encapsulating material 600 on the front surface of the first chip 100, and a second redistribution layer 210 is formed on the front surface of the second chip 200, so that a part of the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the second through hole 820, the intermediate redistribution layer 220, and the conductive material in the third through hole 830, as shown in
It should be noted that, in the present embodiment, before filling the conductive material into the third through hole 830, an insulation material needs to be first covered on an inner wall of the through hole, and then the conductive material is filled into the third through hole 830, so as to prevent the conductive material from being in direct electrical contact with a silicon material inside the second chip 200.
Step S217, forming a pad layer and solder balls 230 on the second redistribution layer 210.
Optionally, in some other possible embodiments, it is also feasible that the second redistribution layer 210 is formed on the second chip 200 in advance, that is, the second chip 200 formed with the second redistribution layer 210 in advance is provided, and then steps such as bonding the two chips, forming the second through hole 820 and the third through hole 830, and filling the conductive material are carried out.
Based on the above design, compared with the prior art solution in which TSV through holes need to be formed on the chips first, then the conductive patterns or solder points formed in advance are accurately aligned with the TSV through holes, in the chip packaging method provided in the present embodiment, it is feasible that the TSV through holes and the conductive patterns do not need to be formed in advance on the first chip 100 or the second chip 200, thus, the need for alignment accuracy of chips can be reduced, and the process difficulty is reduced.
Optionally, referring to
Step S221: providing a third chip 300, wherein the third chip 300 includes a front surface and a back surface, the front surface of the third chip 300 is a functional surface, the back surface of the third chip 300 is a non-functional surface, the front surface of the third chip 300 includes a plurality of pins, the plurality of pins on the front surface of the third chip 300 may be pins disposed on the third redistribution layer 310 on the front surface of the third chip 300 or pin pads directly formed on the front surface of the third chip 300.
Step S222, bonding a part of the pins on the front surface of the third chip 300 and a part of the pins on the first redistribution layer 110 by a bonding material, so that a part of the pins on the front surface of the third chip 300 are electrically connected with a part of the pins on the first redistribution layer 110.
For example, referring to
Optionally, referring to
Step S223: providing a third chip 300, wherein the third chip 300 includes a front surface and a back surface, the front surface of the third chip 300 is a functional surface, the back surface of the third chip 300 is a non-functional surface, the front surface of the third chip 300 includes a plurality of pins, the plurality of pins on the front surface of the third chip 300 may be pins disposed on the third redistribution layer 310 on the front surface of the third chip 300 or pin pads directly formed on the front surface of the third chip 300.
Step S224, forming, when forming the second through hole 820 or after forming the first redistribution layer 110, a fifth through hole 850 penetrating from the encapsulating material 600 to the second redistribution layer 210 and filled with an insulation layer and a conductive material.
Step S225: bonding the front surface of the third chip 300 to the side of the encapsulating material 600 close to the front surface of the first chip 100, so that a part of the pins on the third chip 300 are in electrical contact with the conductive material in the fifth through hole 850, accordingly a part of the pins on the front surface of the third chip 300 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the fifth through hole 850.
For example, in the present embodiment, the third redistribution layer 310 may include a pin 312 for electrical contact with the second redistribution layer 210. Referring to
It should be noted that, in the present embodiment, the third chip 300 may only have the pin 311 or the pin 312, and also may have both the pin 311 and the pin 312, as shown in
Optionally, after bonding the third chip 300, the method may further include wrapping the third chip 300 with the encapsulating material 600.
Optionally, in the present embodiment, the method may further include forming a fourth through hole 840 and filling the fourth through hole 840 with the conductive material, wherein the fourth through hole 840 penetrates from the first redistribution layer 110 to the second redistribution layer 210 through the encapsulating material 600, and a part of the pins on the first redistribution layer 110 are electrically connected with a part of the pins on the second redistribution layer 210 through the conductive material in the fourth through hole 840.
It should be indicated that herein, relational terms such as first and second are merely used for distinguishing one entity or operation from another entity or operation, while it is not necessarily required or implied that these entities or operations have any such practical relation or order. Moreover, terms “including”, “containing” or any other derivatives thereof are intended to be non-exclusive, thus a process, method, article or device including a series of elements not only include those elements, but also include other elements that are not listed definitely, or further include elements inherent to such process, method, article or device. Without more restrictions, an element defined with wordings “including a . . . ” does not exclude presence of other same elements in the process, method, article or device including said element.
The above-mentioned are merely various embodiments of the present disclosure, but the scope of protection of the present disclosure is not limited thereto, and any change or substitution that may easily occur to those skilled in the present art within the technical scope disclosed in the present disclosure should be covered within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection of the claims.
For the chip packaging structure and method provided in the present disclosure, in the solutions provided in the present embodiment, the TSV hole passing through a silicon material may not need to be formed in advance on the chips before bonding the chips, thereby the requirement of alignment accuracy of the chips can be reduced, and the process difficulty can be reduced. In addition, as the back-to-back packaging process is adopted, the heat dissipation efficiency of the chips can be improved, and the problem of circuit breakage due to materials with different expansion coefficients present between the chips can be avoided.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2020/096347 | 6/16/2020 | WO | 00 |