This U.S. non-provisional patent application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2023-0082150, filed on Jun. 26, 2023, in the Korean Intellectual Property Office, the entire contents of which are hereby incorporated by reference.
The disclosure relates to a semiconductor package and a method of fabricating the same, and in particular, to a semiconductor package including a redistribution substrate and a conductive post and a method of fabricating the same.
A semiconductor package is configured to facilitate the use of an integrated circuit chip as a component in an electronic product. In general, the semiconductor package includes a printed circuit board (PCB) and a semiconductor chip, which is mounted on the PCB and is electrically connected to the PCB using bonding wires or bumps. As the electronics industry advances, various studies are being conducted to develop a highly reliable, highly integrated, and compact semiconductor package.
In light of recent advancements in the electronics industry, the demand for high-performance, high-speed, and compact electronic components has been steadily increasing. As an integration density of a semiconductor chip increases, a size of a semiconductor chip is gradually decreasing. However, in the case where the size of the semiconductor chip is reduced, it is increasingly difficult to attach many solder balls to the semiconductor chip and to handle and test the solder balls. In addition, it is necessary to diversify a board in accordance with a size of a semiconductor chip, and this is another difficult problem. As a result, recent packaging technology is progressing in the direction of integrating a plurality of semiconductor chips within a single package. One example is a fan-out wafer-level package (FO-WLP). In the FO-WLP, mold-through vias (MTVs) are used to electrically connect redistribution patterns, which are placed on or under a semiconductor chip, and this may enable vertical stacking of boards mounted with the semiconductor chips.
The disclosure provides a method of reducing a failure rate in a process of fabricating a semiconductor package and a semiconductor package fabricated thereby.
The disclosure also provides a semiconductor package, which has an improved electric connection structure and high driving stability, and a method of fabricating the same.
The disclosure also provides a semiconductor package with improved heat-dissipation characteristics and a method of fabricating the same.
According to an aspect of the disclosure, a method of fabricating a semiconductor package includes: providing an insulating layer; forming a seed layer to cover a top surface of the insulating layer; forming a sacrificial layer on the seed layer; forming penetration holes to penetrate the sacrificial layer and expose the seed layer; forming conductive posts in the penetration holes; removing the sacrificial layer; performing a laser irradiation process on the seed layer to form seed patterns below the conductive posts; attaching a semiconductor chip to a portion of the insulating layer located between the conductive posts; and removing the insulating layer, wherein an outer side surface of the conductive posts and an outer side surface of the seed patterns are substantially coplanar with each other, thereby forming a substantially flat surface.
According to an aspect of the disclosure, a method of fabricating a semiconductor package includes: providing an insulating layer; forming a seed layer to cover a top surface of the insulating layer; forming a sacrificial layer on the seed layer; forming a penetration hole to penetrate the sacrificial layer and expose the seed layer; forming a conductive post in the penetration hole; removing the sacrificial layer; irradiating a laser onto the seed layer and the conductive post to form a seed pattern below the conductive post and a heat-dissipation pattern beside the conductive post; attaching a semiconductor chip to the heat-dissipation pattern; and removing the insulating layer, wherein the conductive post is not etched by the irradiating of the laser, and the seed layer is etched by the irradiating of the laser.
According to an aspect of the disclosure, a method of fabricating a semiconductor package includes: providing an insulating layer; forming a seed layer to cover a top surface of the insulating layer; forming a sacrificial layer on the seed layer; forming a penetration hole to penetrate the sacrificial layer and expose the seed layer; forming a conductive post in the penetration hole; removing the sacrificial layer; directly irradiating a laser onto the seed layer and the conductive post to form a seed pattern below the conductive post and a heat-dissipation pattern beside the conductive post; attaching a semiconductor chip to the heat-dissipation pattern; and removing the insulating layer, wherein a width of the conductive post is equal to a width of the seed pattern.
The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
The following will now describe one or more embodiments of the disclosure in conjunction with the accompanying drawings.
In this description, the phrase “a certain component is connected or coupled to a different component” may be interpreted as that “the certain component is directly connected to the different component” or “an intervening element is present between the certain component and the different component.” The phrase “a certain component is in contact with a different component” may mean that “no intervening element is interposed between the certain component and the different component.”
Also, when a part “includes” or “comprises” an element, unless there is a particular description contrary thereto, the part may further include other elements, not excluding the other elements.
It will be understood that, although the terms first, second, third, etc., may be used herein to describe various elements, is the disclosure should not be limited by these terms. These terms are only used to distinguish one element from another element.
As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
An identification code is used for the convenience of the description but is not intended to illustrate the order of each step. Each step may be implemented in an order different from the illustrated order unless the context clearly indicates otherwise.
Herein, the expression “at least one of a, b or c” indicates “only a,” “only b,” “only c,” “both a and b,” “both a and c,” “both b and c,” or “all of a, b, and c.”
Referring to
The first substrate insulating pattern 110 may be formed of or include at least one of insulating polymers or photoimageable polymers (e.g., photoimageable dielectric (PID) materials). For example, the photoimageable polymers may include at least one of photoimageable polyimide (PI), polybenzoxazole (PBO), phenol-based polymers, or benzocyclobutene-based polymers. Alternatively, the first substrate insulating pattern 110 may include an insulating material. For example, the first substrate insulating pattern 110 may be formed of or include silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), or insulating polymers.
The first substrate interconnection pattern 120 may be provided on the first substrate insulating pattern 110. The first substrate interconnection pattern 120 may be horizontally extended, on the first substrate insulating pattern 110. The first substrate interconnection pattern 120 may be provided on a bottom surface of the first substrate insulating pattern 110. The first substrate interconnection pattern 120 may include a portion that is exposed to the outside of the first substrate insulating pattern 110 near the bottom surface of the first substrate insulating pattern 110. The first substrate interconnection pattern 120 under the first substrate insulating pattern 110 may be covered with another first substrate insulating pattern 110 thereunder. A portion 130 of the first substrate interconnection pattern 120, which is provided in the lowermost one of the first substrate interconnection layers, may be coupled to an outer terminal 150, which will be described below, and will be referred to as a substrate pad 130. As described above, the first substrate interconnection pattern 120 may serve as a pad portion or a wire portion of the first substrate interconnection layer. That is, the first substrate interconnection pattern 120 may be an element for a horizontal redistribution of the first redistribution substrate 100. The first substrate interconnection pattern 120 may include a conductive material. For example, the first substrate interconnection pattern 120 may be formed of or include at least one of metallic materials (e.g., copper (Cu)).
The first substrate interconnection pattern 120 may have a damascene structure. For example, the first substrate interconnection pattern 120 may include a via portion that is protrudingly extended upward from a top surface thereof. The via portion may be configured to vertically connect the first substrate interconnection patterns 120, which are included in adjacent ones of the first substrate interconnection layers, to each other. Alternatively, the via portion may be an element, which is used to connect the first substrate interconnection pattern 120 of the uppermost one of the first substrate interconnection layers to a semiconductor chip 200 and a conductive post 350 to be described below. For example, the via portion may be extended from a top surface of the first substrate interconnection pattern 120 to penetrate the first substrate insulating pattern 110 and may be connected to a bottom surface of the first substrate interconnection pattern 120 of another first substrate interconnection layer thereon. Also, the via portion may be extended from the top surface of the first substrate interconnection pattern 120 to penetrate the uppermost one of the first substrate insulating patterns 110 and may be connected to a bottom surface of the conductive post 350 or to a first chip circuit layer 220 of the semiconductor chip 200. That is, a lower portion of the first substrate interconnection pattern 120, which is provided under the bottom surface of the first substrate insulating pattern 110, may be a head portion, which is used as a horizontal wire or a pad, and the via portion of the first substrate interconnection patterns 120 may be a tail portion. The first substrate interconnection patterns 120 may have an inverted shape of the letter “T”.
A barrier layer may be interposed between the first substrate insulating pattern 110 and the first substrate interconnection patterns 120. The barrier layer may be provided to enclose the head and tail portions of the first substrate interconnection patterns 120. A thickness of a gap between the first substrate interconnection patterns 120 and the first substrate insulating pattern 110 (i.e., the barrier layer) may range from 50 Å to 1000 Å. The barrier layer may be formed of or include at least one of titanium (Ti), tantalum (Ta), titanium nitride (TiN), or tantalum nitride (TaN).
A substrate protection layer 140 may be provided. The substrate protection layer 140 may cover a bottom surface of the lowermost one of the first substrate interconnection layers. Here, the substrate protection layer 140 may enclose the substrate pads 130 on the lowermost one of the first substrate insulating patterns 110. The substrate pads 130 may be exposed to the outside of the substrate protection layer 140 near a bottom surface of the substrate protection layer 140. The substrate protection layer 140 may be formed of or include at least one of insulating polymers or photoimageable polymers (e.g., photoimageable dielectric (PID) materials). In an embodiment, the substrate protection layer 140 may not be provided.
The outer terminals 150 may be provided on the exposed bottom surfaces of the substrate pads 130. The outer terminals 150 may include solder balls or solder bumps, and the semiconductor package may be classified into a ball grid array (BGA) package, a fine ball-grid array (FBGA) package, or a land grid array (LGA) package, depending on the kind and arrangement of the outer terminals 150.
The semiconductor chip 200 may be disposed on the first redistribution substrate 100. When viewed in a plan view, the semiconductor chip 200 may be disposed on a center region of the first redistribution substrate 100. The semiconductor chip 200 may be a logic chip. Alternatively, the semiconductor chip 200 may be a memory chip, such as a DRAM, SRAM, MRAM, or FLASH memory chip. The semiconductor chip 200 may have a front surface and a rear surface. Hereinafter, in the present specification, the front surface may be a surface of a semiconductor chip, which is called an active surface, and on which integrated devices or pads are formed, and the rear surface may be another surface of the semiconductor chip that is opposite to the front surface. The semiconductor chip 200 may be disposed such that the front surface thereof faces the first redistribution substrate 100. That is, the semiconductor chip 200 may be disposed on the first redistribution substrate 100 in a face-down manner. The semiconductor chip 200 may include a chip base layer 210 and a chip circuit layer 220, which is provided on the front surface of the chip base layer 210.
The chip base layer 210 may be formed of or include silicon (Si). Integrated devices or integrated circuits may be formed in a lower portion of the chip base layer 210.
The chip circuit layer 220 may be provided on a bottom surface of the chip base layer 210. The chip circuit layer 220 may be electrically connected to the integrated device or the integrated circuit, which is formed in the chip base layer 210. For example, the chip circuit layer 220 may include a chip circuit insulating pattern 222 and a chip circuit pattern 224, which is provided in the chip circuit insulating pattern 222 and is coupled to the integrated device or the integrated circuit formed in the chip base layer 210. The chip circuit pattern 224 may include a portion 225, which is exposed to the outside of the chip circuit layer 220 near a bottom surface of the chip circuit layer 220 and is used as a chip pad of the semiconductor chip 200. A bottom surface of the semiconductor chip 200, on which the chip circuit layer 220 is provided, may be an active surface of the semiconductor chip 200.
The semiconductor chip 200 may be mounted on the first redistribution substrate 100. For example, the semiconductor chip 200 may be disposed such that the chip circuit layer 220 faces a top surface of the first redistribution substrate 100. The chip circuit layer 220 of the semiconductor chip 200 may be in contact with the top surface of the first redistribution substrate 100. At an interface between the semiconductor chip 200 and the first redistribution substrate 100, the chip pads 225 of the semiconductor chip 200 may be in contact with the first substrate interconnection patterns 120 of the first redistribution substrate 100. For example, a portion of the first substrate interconnection pattern 120 in the uppermost one of the first substrate interconnection layers of the first redistribution substrate 100 may penetrate the first substrate insulating pattern 110 and may be coupled to the chip pad 225.
In an embodiment, the semiconductor chip 200 may not be in contact with the top surface of the first redistribution substrate 100. For example, the semiconductor chip 200 may be vertically spaced apart from the top surface of the first redistribution substrate 100. In this case, the portion of the first substrate interconnection pattern 120 of the first redistribution substrate 100 may be extended toward the semiconductor chip 200 to penetrate the first substrate insulating pattern 110 and may be coupled to the chip pad 225.
A heat-dissipation pattern 250 may be provided on the semiconductor chip 200. The heat-dissipation pattern 250 may have a plate shape. A planar shape of the heat-dissipation pattern 250 may be substantially equal or similar to a planar shape of the semiconductor chip 200. For example, as shown in
The heat-dissipation pattern 250 may be attached to the top surface of the semiconductor chip 200 using a chip adhesive layer 252. The chip adhesive layer 252 may be attached to the top surface of the semiconductor chip 200 and a bottom surface of the heat-dissipation pattern 250. The chip adhesive layer 252 may cover the entire top surface of the semiconductor chip 200. For example, side surfaces of the chip adhesive layer 252 may be vertically aligned to the side surfaces of the semiconductor chip 200 and the side surfaces 250a of the heat-dissipation pattern 250. However, the disclosure is not limited to this example. The chip adhesive layer 252 may include an adhesive tape. The chip adhesive layer 252 may be formed of or include a thermal interface material (TIM) (e.g., thermal grease).
A mold layer 300 may be provided on the first redistribution substrate 100. The mold layer 300 may cover the top surface of the first redistribution substrate 100. The mold layer 300 may enclose the semiconductor chip 200, when viewed in a plan view. In an embodiment, the mold layer 300 may cover the side surfaces of the semiconductor chip 200, but not the top surface of the semiconductor chip 200. In detail, a top surface of the mold layer 300 may be located at a level higher than the top surface of the semiconductor chip 200. Here, the top surface of the semiconductor chip 200 may mean a top surface of the chip base layer 210 of the semiconductor chip 200. The top surface of the semiconductor chip 200 may be closer to the first redistribution substrate 100 than the top surface of the mold layer 300. The mold layer 300 may not cover a top surface of the heat-dissipation pattern 250. In detail, the mold layer 300 may be provided to enclose the chip adhesive layer 252 and the heat-dissipation pattern 250, which are provided on the semiconductor chip 200, and the heat-dissipation pattern 250 may be exposed to the outside of the mold layer 300 near the top surface of the mold layer 300. The top surface of the mold layer 300 and the top surface of the heat-dissipation pattern 250 may be substantially coplanar with each other, thereby forming a substantially flat surface. In another embodiment, the mold layer 300 may cover the top surface of the heat-dissipation pattern 250. In other words, the semiconductor chip 200, the chip adhesive layer 252, and the heat-dissipation pattern 250 may be buried in the mold layer 300. Hereinafter, the disclosure will be further described with reference to the embodiment of
In the case where the semiconductor chip 200 is not in contact with the first redistribution substrate 100, the mold layer 300 may be extended into a region between the semiconductor chip 200 and the first redistribution substrate 100. The mold layer 300 may fill a space between the semiconductor chip 200 and the first redistribution substrate 100. The mold layer 300 may enclose the portion of the first substrate interconnection pattern 120, which is extended from the first redistribution substrate 100 to the chip pad 225.
At least one of conductive post 350 may be provided on the first redistribution substrate 100. The conductive posts 350 may be placed next to or around the semiconductor chip 200. The conductive posts 350 may be provided to vertically penetrate the mold layer 300. The conductive post 350 may be extended toward the first redistribution substrate 100 and may be coupled to the first substrate interconnection pattern 120 of the first redistribution substrate 100. Also, the conductive post 350 may be extended toward the top surface of the mold layer 300. Top surfaces of the conductive posts 350 may be located at a level lower than the top surface of the mold layer 300. In other words, the top surfaces of the conductive posts 350 may be closer to the first redistribution substrate 100 than the top surface of the mold layer 300. A difference in level between the top surfaces of the conductive posts 350 and the top surface of the mold layer 300 may range from 1 nm to 900 nm. An outer side surface 350a of the conductive post 350 may be substantially flat. The outer side surface 350a of the conductive posts 350 may be perpendicular to the top surface of the first redistribution substrate 100. The width W of the conductive post 350 may be substantially uniform. The width W of the conductive posts 350 may range from 1 μm to 1 mm. A second thickness T2 of the conductive posts 350 may range from 1 μm to 1 mm. Here, the thickness may mean a height from the top surface of the first redistribution substrate 100 in a vertical direction. The conductive posts 350 may be provided to have an aspect ratio of 2 to 10. The conductive posts 350 may be formed of or include copper (Cu).
Seed patterns 360 may be provided on the conductive posts 350. The seed patterns 360 may be connected to the conductive posts 350, respectively. The description that follows will refer to one seed pattern 360 and one the conductive post 350, which are connected to each other. The seed pattern 360 may be in contact with a top surface of the conductive post 350. A top surface of the seed pattern 360 and the top surface of the mold layer 300 may be substantially coplanar with each other, thereby forming a substantially flat surface. In other words, the mold layer 300 may have a penetration hole, which is formed to penetrate the mold layer 300 and expose the first substrate interconnection pattern 120 of the first redistribution substrate 100, and the conductive post 350 and the seed pattern 360 may be provided to fill the penetration hole. The conductive post 350 and the seed pattern 360 may be enclosed by the mold layer 300. The seed pattern 360 may have substantially the same planar shape as the conductive post 350. For example, a width of the seed pattern 360 may be equal to the width W of the conductive post 350. The width of the seed pattern 360 may be uniform. An outer side surface 360a of the seed pattern 360 may be vertically aligned to the outer side surface 350a of the conductive post 350. The outer side surface 360a of the seed pattern 360 and the outer side surface 350a of the conductive post 350 may be substantially coplanar with each other, thereby forming a flat surface. A third thickness T3 of the seed pattern 360 may be equal to the first thickness T1 of the heat-dissipation pattern 250. The third thickness T3 of the seed pattern 360 may range from 1 nm to 900 nm. The seed pattern 360 may be formed of the same material as the heat-dissipation pattern 250. The seed pattern 360 may be formed of or include a metallic material. For example, the seed pattern 360 may be formed of or include gold (Au), copper (Cu), or titanium (Ti). The structure with one seed pattern 360 and one conductive post 350 has been described, and the remaining ones of the seed patterns 360 and the conductive posts 350 may be configured to have substantially the same features as the afore-described structure.
According to an embodiment of the disclosure, the outer side surface 360a of the seed pattern 360 may be substantially coplanar with the outer side surface 350a of the conductive post 350. In other words, the seed pattern 360 may not have any under-cut region, near the conductive post 350. Accordingly, it may be possible to prevent the conductive posts 350 from being disconnected or detached from a second redistribution substrate 400, which will be described below, or from the seed patterns 360 by the under-cut region, and thus, the semiconductor package may have improved structural stability.
Furthermore, the seed patterns 360 may have substantially the same planar shape as the conductive posts 350. That is, the seed patterns 360 may be provided to have a large area without the under-cut region, and in this case, the seed pattern 360 and the conductive post 350 may be in contact with each other with a large contact area. Thus, an electric resistance or interface resistance between the conductive post 350 and the seed pattern 360 may be lowered, and this make it possible to realize a semiconductor package with improved electric characteristics.
Referring further to
The second redistribution substrate 400 may be a substrate for redistribution. For example, the second redistribution substrate 400 may include at least one of second substrate interconnection layer. Each of the second substrate interconnection layers may include a second substrate insulating pattern 410 and a second substrate interconnection pattern 420 in the second substrate insulating pattern 410. The second substrate interconnection patterns 420, which are respectively provided in adjacent ones of the second substrate interconnection layers, may be electrically connected to each other.
The second substrate insulating pattern 410 may be formed of or include at least one of insulating polymers or photoimageable polymers (e.g., photoimageable dielectric (PID) materials). For example, the photoimageable polymers may include at least one of photoimageable polyimide (PI), polybenzoxazole (PBO), phenol-based polymers, or benzocyclobutene-based polymers. Alternatively, the second substrate insulating pattern 410 may include an insulating material. For example, the second substrate insulating pattern 410 may be formed of or include silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), or insulating polymers.
The second substrate interconnection pattern 420 may be provided on the second substrate insulating pattern 410. The second substrate interconnection pattern 420 may be horizontally extended, on the second substrate insulating pattern 410. The second substrate interconnection pattern 420 may be provided on a top surface of the second substrate insulating pattern 410. The second substrate interconnection pattern 420 may include a portion that is exposed to the outside of the second substrate insulating pattern 410 near the top surface of the second substrate insulating pattern 410. The second substrate interconnection pattern 420 on the second substrate insulating pattern 410 may be covered with another second substrate insulating pattern 410 thereon. A portion of the second substrate interconnection pattern 420 in the uppermost one of the second substrate interconnection layers may be used as a substrate pad, which is coupled to an external device, another package, or another chip. As described above, the second substrate interconnection pattern 420 may be used as the pad or wire portion of the second substrate interconnection layer. In other words, the second substrate interconnection pattern 420 may be an element for a horizontal redistribution in the second redistribution substrate 400. The second substrate interconnection pattern 420 may include a conductive material. For example, the second substrate interconnection pattern 420 may be formed of or include a metallic material (e.g., copper (Cu)).
The second substrate interconnection pattern 420 may have a damascene structure. For example, the second substrate interconnection pattern 420 may include a via portion that is protrudingly extended downward from a bottom surface thereof. The via portion be configured to vertically connect the second substrate interconnection patterns 420, which are included in adjacent ones of the second substrate interconnection layers, to each other. For example, the via portion may be extended from a bottom surface of the second substrate interconnection pattern 420 to penetrate the second substrate insulating pattern 410 and may be connected to a top surface of the second substrate interconnection pattern 420 of another second substrate interconnection layer thereunder. Alternatively, the via portion may be an element, which is used to connect the second substrate interconnection pattern 420 of the lowermost one of the second substrate interconnection layers to the seed pattern 360. For example, the via portion may be extended from the top surface of the second substrate interconnection pattern 420 to penetrate the lowermost one of the second substrate insulating patterns 410 and may be connected to the top surface of the seed pattern 360. That is, an upper portion of the second substrate interconnection pattern 420, which is placed on the top surface of the second substrate insulating pattern 410, may be a head portion, which is used as a horizontal wire or pad, and the via portion of the second substrate interconnection pattern 420 may be a tail portion. The second substrate interconnection patterns 420 may have a shape of the letter ‘T’.
A barrier layer may be interposed between the second substrate insulating pattern 410 and the second substrate interconnection patterns 420. The barrier layer may enclose the head and tail portions of the second substrate interconnection patterns 420. A thickness of a gap between the second substrate interconnection patterns 420 and the second substrate insulating pattern 410 (i.e., the barrier layer) may range from 50 Å to 1000 Å. The barrier layer may be formed of or include at least one of titanium (Ti), tantalum (Ta), titanium nitride (TiN), or tantalum nitride (TaN).
A portion 422 of the second substrate interconnection pattern 420 may be used to exhaust heat of the semiconductor chip 200 to the outside, and thus, it will be referred to as a heat transfer pattern 422. For example, the heat transfer pattern 422 may be a portion of the second substrate interconnection pattern 420, which is placed on the semiconductor chip 200. The heat transfer pattern 422 may penetrate the lowermost one of the second substrate insulating patterns 410 and may be connected to the top surface of the heat-dissipation pattern 250. The heat-dissipation pattern 250 may have various planar shapes. Here, the planar shape of the heat-dissipation pattern 250 may mean a shape of the via portion of the heat-dissipation pattern 250, when viewed from the top or bottom of the heat-dissipation pattern 250.
As shown in
In an embodiment, as shown in
In an embodiment, as shown in
In an embodiment, as shown in
So far, some examples of the planar shape of the heat transfer pattern 422 have been described with reference to
The head portion of the heat-dissipation pattern 250 may have the same or similar shape as the via portion of the heat-dissipation pattern 250 or have a plate shape, when viewed in a plan view.
The heat transfer pattern 422 may be electrically disconnected from the semiconductor chip 200. For example, the second substrate interconnection pattern 420 of the second redistribution substrate 400 may include a first portion that is connected to the semiconductor chip 200 through the conductive posts 350 and the first redistribution substrate 100. Also, the second substrate interconnection pattern 420 of the second redistribution substrate 400 may include a second portion that is not electrically connected to the first portion of the second substrate interconnection pattern 420. The second portion of the second substrate interconnection pattern 420 may be coupled to the heat transfer pattern 422. However, the disclosure is not limited to this example. In an embodiment, the heat transfer pattern 422 may be a portion of the second substrate interconnection pattern 420 electrically connected to the semiconductor chip 200. Heat, which is generated in the semiconductor chip 200, may be transferred to the heat transfer pattern 422 through the heat-dissipation pattern 250. In this case, the heat in the heat transfer pattern 422 may be exhausted to a region on the second redistribution substrate 400 through the second substrate interconnection pattern 420.
According to an embodiment of the disclosure, the heat-dissipation pattern 250 may be provided on a rear surface of the semiconductor chip 200, and the second substrate interconnection pattern 420 of the second redistribution substrate 400, which is placed on the rear surface of the semiconductor chip 200, may be used as the heat transfer pattern 422 for heat dissipation. Accordingly, the heat-dissipation efficiency of the semiconductor package may be improved.
The second substrate interconnection pattern 420 may have a damascene structure. For example, the second substrate interconnection pattern 420 may include a via portion that is protrudingly extended upward from a top surface thereof. The via portion may be extended from the top surface of the second substrate interconnection pattern 420 to penetrate the second substrate insulating pattern 410 and may be connected to a bottom surface of the second substrate interconnection pattern 420 of another second substrate interconnection layer thereon. A lower portion of the second substrate interconnection pattern 420, which is placed on the bottom surface of the second substrate insulating pattern 410, may be a head portion, which is used as a horizontal wire or pad, and the via portion of the second substrate interconnection pattern 420 may be a tail portion. The second substrate interconnection patterns 420 may have an inverted shape of the letter ‘T’.
The heat transfer pattern 422 may be a portion of the second substrate interconnection pattern 420, which is placed on the semiconductor chip 200. Here, the planar shape of the heat-dissipation pattern 250 may mean a shape of the head portion of the heat-dissipation pattern 250, when viewed from the top or bottom of the heat-dissipation pattern 250.
Referring to
The lower package 10 may have the same or similar structure as that of
The upper package 20 may have the same or similar structure as that of
The upper package 20 may be mounted on the lower package 10. For example, the outer terminals 150 may be provided on the substrate pads 130 of the upper package 20. The outer terminals 150 of the upper package 20 may be coupled to the upper substrate pads 430 of the lower package 10.
Referring to
An insulating layer 910 may be formed on the carrier substrate 900. For example, the insulating layer 910 may be formed by depositing or coating an insulating material on the top surface of the carrier substrate 900. The insulating layer 910 may cover the entire top surface of the carrier substrate 900. The insulating layer 910 may include a photoresist material. The insulating layer 910 may be formed of or include at least one of polyimide (PI) or PI-based polymers.
A seed layer 920 may be formed on the insulating layer 910. For example, the seed layer 920 may be formed by attaching a metal foil of a metallic material to the insulating layer 910 or by depositing or plating the metallic material on the insulating layer 910. The seed layer 920 may cover the entire top surface of the insulating layer 910. A thickness of the seed layer 920 may range from 1 nm to 1 μm. In particular, the thickness of the seed layer 920 may range from 1 nm to 900 nm. In the case where the thickness of the seed layer 920 is larger than 1 μm, there may be a difficulty in a process of patterning the seed layer 920 to be described below. In the case where the thickness of the seed layer 920 is smaller than 1 nm, there may be difficulty in achieving a high uniformity in the thickness of the seed layer 920. As an example, there may be a technical issue, such as non-deposition, non-plating, or loss of the seed layer 920, in some regions. The metallic material may contain a metal element (e.g., copper (Cu)).
Referring to
Penetration holes may be formed in the sacrificial layer 930. For example, the penetration holes may be formed by performing an exposure and developing process on the sacrificial layer 930. The penetration holes may vertically penetrate the sacrificial layer 930 and expose a top surface of the seed layer 920.
The conductive posts 350 may be formed in the penetration holes. For example, the penetration hole may be filled with a metallic material by a plating process using the seed layer 920, which is exposed through the penetration hole, as a seed layer. The metallic material may be formed to fill the penetration hole and cover a top surface of the sacrificial layer 930. Thereafter, an etch-back process may be performed on the metallic material to form the conductive post 350 in the penetration hole. In an embodiment, the etch-back process may be performed to remove a portion of the metallic material, which is placed on the top surface of the sacrificial layer 930 and in upper regions of the penetration holes. In an embodiment, the plating process may be performed such that a top surface of the metallic material is located within the penetration holes. The metallic material in the penetration holes may constitute the conductive posts 350.
In another embodiment, a seed/barrier layer may be formed in the penetration holes before the formation of the conductive posts 350. For example, the seed/barrier layer may be formed by depositing or coating a metal layer to conformally cover the side and bottom surfaces of the penetration holes and the top surface of the sacrificial layer 930. The seed/barrier layer may be formed of or include at least one of metallic materials (e.g., gold (Au), titanium (Ti), and tantalum (Ta)) or metal nitride materials (e.g., titanium nitride (TiN) and tantalum nitride (TaN)). In an embodiment, the seed/barrier layer may not be formed.
In the case where the seed/barrier layer is formed in the penetration hole, a plating process may be performed using the seed/barrier layer as a seed layer. A metallic material, which fills the penetration holes and covers the top surface of the sacrificial layer 930, may be formed through the plating process, and then, the conductive posts 350 may be formed by removing the metallic material and the seed/barrier layer from the top surface of the sacrificial layer 930. Hereinafter, the disclosure will be described with reference to the embodiment of
Referring to
As a result of the removal of the sacrificial layer 930, the top surface of the seed layer 920 and the outer side surfaces of the conductive posts 350 may be exposed to the outside.
Referring to
According to an embodiment of the disclosure, the seed layer 920, but not the conductive posts 350, may be patterned by the laser irradiation process, even without using an additional mask pattern. In addition, the outer side surface of the seed patterns 360 and the outer side surface of the conductive posts 350 may be coplanar with each other, thereby forming a flat surface. In the case where a patterning process using etching solution is used, the seed patterns 360 under the conductive posts 350 may be over-etched to form an under-cut region, but according to an embodiment of the disclosure, the under-cut region may not be formed in the seed patterns 360. Thus, it may be possible to prevent an adhesive strength between the seed patterns 360 and the conductive posts 350 or between the seed patterns 360 and the insulating layer 910 from being deteriorated by the under-cut region and thereby prevent the conductive posts 350 from being detached from the insulating layer 910. In addition, since the conductive posts 350 is thick enough to be hardly etched by the laser LA, the conductive posts 350 may not be deformed during the process of patterning the seed layer 920. That is, it may be possible to reduce a failure rate in a process of fabricating a semiconductor package.
Moreover, the seed patterns 360 and the heat-dissipation pattern 250 may be formed simultaneously using just one seed layer (i.e., 920), and thus, the fabrication process of the semiconductor package may be simplified.
Referring to
Since the seed layer 920 is commonly used to form the heat-dissipation pattern 250 and the seed patterns 360, the heat-dissipation pattern 250 and the seed patterns 360 may be formed to have substantially the same thickness. For example, the thickness of the heat-dissipation pattern 250 and the thickness of the seed patterns 360 may range from 1 nm to 900 nm.
In another embodiment, before the laser irradiation process, a mask pattern MP may be formed on the portion 250 of the seed layer 920, as shown in
Referring to
The semiconductor chip 200 may be attached to the heat-dissipation pattern 250. The semiconductor chip 200 may be attached to the heat-dissipation pattern 250 using the chip adhesive layer 252. That is, the semiconductor chip 200 may be attached to the heat-dissipation pattern 250 in a face-up manner. The planar shape of the semiconductor chip 200 may correspond to the planar shape of the heat-dissipation pattern 250. However, the disclosure is not limited to this example, and in an embodiment, the heat-dissipation pattern 250 may have the same planar shape as the semiconductor chip 200, like the embodiment of
Referring to
Thereafter, a planarization process may be performed on the mold layer 300. An upper portion of the mold layer 300 may be removed by the planarization process. The planarization process may include a chemical mechanical polishing (CMP) process. The planarization process may be performed to expose the top surface of the semiconductor chip 200 and the top surfaces of the conductive posts 350. The top surface of the semiconductor chip 200 may be a top surface of the chip circuit layer 220 exposing the chip pads 225 of the semiconductor chip 200.
Referring to
Referring to
Next, a structure including the first redistribution substrate 100, the semiconductor chip 200, the heat-dissipation pattern 250, the mold layer 300, the conductive posts 350, and the seed patterns 360 may be inverted. Thus, the surfaces of the mold layer 300, the seed patterns 360, and the heat-dissipation pattern 250, which are exposed by removing the insulating layer 910 and the carrier substrate 900, may become the top surfaces of the mold layer 300, the seed patterns 360, and the heat-dissipation pattern 250.
Referring back to
The outer terminals 150 may be provided on the substrate pads 130 of the first redistribution substrate 100.
As a result of the afore-described fabrication process, the semiconductor package may be fabricated to have the structure of
In an embodiment, the second redistribution substrate 400 may be formed, and then the semiconductor chip 200, the heat-dissipation pattern 250, the mold layer 300, the conductive posts 350, and the seed patterns 360 may be formed. For example, the second redistribution substrate 400 may be formed on the carrier substrate 900. The second substrate insulating pattern 410 may be formed by depositing an insulating material on the carrier substrate 900 to form an insulating layer and patterning the insulating layer, the second substrate interconnection pattern 420 may be formed by forming a conductive layer on the second substrate insulating pattern 410 and patterning the conductive layer, and in this case, the second substrate insulating pattern 410 and the second substrate interconnection pattern 420 may form one second substrate interconnection layer. The second redistribution substrate 400 may be formed by repeating the process of forming the second substrate interconnection layer. The insulating layer 910 may be formed on the second redistribution substrate 400 to expose the second substrate interconnection pattern 420, the seed layer 920 and the conductive posts 350 on the seed layer 920 may be formed, and a laser irradiation process may be performed to form the seed patterns 360 and the heat-dissipation pattern 250. The semiconductor chip 200 may be attached to the heat-dissipation pattern 250, and the mold layer 300 may be formed on the second redistribution substrate 400. The first redistribution substrate 100 may be formed on the mold layer 300, and the outer terminals 150 may be attached to the first redistribution substrate 100. Thereafter, the carrier substrate 900 may be removed.
In a semiconductor package according to an embodiment of the disclosure, an outer side surface of a seed pattern may be coplanar with an outer side surface of a conductive post. That is, the seed pattern may be formed without an under-cut region, which is laterally recessed from the outer side surface of the conductive post. Thus, it may be possible to prevent the conductive posts from being detached from a second redistribution substrate or the seed patterns by the under-cut region and thereby improve the structural stability of the semiconductor package. In addition, the seed patterns may have substantially the same planar shape as the conductive posts. That is, the seed patterns may be provided to have a large area, without the under-cut region, and thus, a contact area between the seed patterns and the conductive posts may be increased. Accordingly, an electric resistance or an interface resistance between the conductive posts and the seed patterns may be lowered, and this may make it possible to improve the electrical characteristics of the semiconductor package.
In addition, a heat-dissipation pattern may be provided on a rear surface of a semiconductor chip, and a second substrate interconnection pattern of the second redistribution substrate placed on the rear surface of the semiconductor chip may be used as a heat transfer pattern for exhausting heat. Accordingly, the heat-dissipation efficiency of the semiconductor package may be improved.
In a method of fabricating a semiconductor package according to an embodiment of the disclosure, a laser irradiation process may be performed to pattern the seed layer, but not the conductive posts, even without using an additional mask pattern. Furthermore, of the seed pattern and the conductive post may be formed to have outer side surfaces that are coplanar with each other and form a flat surface. That is, the under-cut region may not be formed in the seed pattern. Thus, it may be possible to prevent an adhesive strength between the seed patterns and the conductive posts or between the seed patterns and an insulating layer from being weakened by the under-cut region and thereby preventing the conductive posts from being detached from the insulating layer. Furthermore, in the case where the conductive post is thick, the conductive post may not be etched by a laser, and thus, the conductive post may not be deformed during a process of patterning the seed layer. That is, it may be possible to reduce a failure rate in a process of fabricating a semiconductor package.
While example embodiments of the disclosure have been particularly shown and described, it will be understood by one of ordinary skill in the art that variations in form and detail may be made therein without departing from the spirit and scope of the attached claims.
Number | Date | Country | Kind |
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10-2023-0082150 | Jun 2023 | KR | national |