Semiconductor memory module including fixing structure

Abstract

A semiconductor memory module is disclosed. The semiconductor memory module includes: a first substrate including a first corner portion; a first semiconductor package mounted on a lower surface of the first substrate; a second substrate disposed above the first substrate and including a second corner portion corresponding to the first corner portion; a second semiconductor package mounted on an upper surface of the second substrate; and a fixing structure in which the first corner portion and the second corner portion are fitted.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Korean Patent Application No. 10-2023-0079770 filed on June 21, 2023 in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The inventive concept relates to a semiconductor memory module, and more particularly, to a semiconductor memory module having improved reliability. Background Art

[0004] Many electronic systems include semiconductor memory modules, such as solid-state drives (SSDs), dual in-line memory modules (DIMMs), and small form factor DIMMs, all of which utilize memory cells to store data as an electrical charge or voltage. Improvements in the storage density of these modules have been achieved by using enhanced manufacturing techniques to increase the density of memory cells on each individual memory component. In addition, the storage density of these modules has also been increased by including more memory components in each memory device or module using advanced board-level packaging techniques. Summary of the invention

[0005] An object of the inventive concept is to provide a semiconductor memory module having improved reliability.

[0006] The benefits provided by the inventive concept are not limited to solving the above-mentioned problems, and other benefits not mentioned will be clearly understood by those skilled in the art from the following description.

[0007] A semiconductor memory module according to some embodiments of the present invention includes: a first substrate including a first corner portion; a first semiconductor package mounted on a lower surface of the first substrate; a second substrate disposed above the first substrate and including a second corner portion corresponding to the first corner portion; a second semiconductor package mounted on an upper surface of the second substrate; and a fixing structure into which the first corner portion and the second corner portion are assembled.

[0008] The semiconductor memory module according to some embodiments of the present invention comprises a housing and a stacking structure accommodated therein, wherein the stacking structure comprises: a first substrate, which comprises a plurality of first corner portions and has a first side surface and a second side surface; a first semiconductor package, which is mounted on a lower surface of the first substrate; a second semiconductor package, which is mounted on an upper surface of the first substrate; a second substrate, which is disposed above the first substrate, comprises a plurality of second corner portions and has a third side surface and a fourth side surface, each second corner portion respectively corresponding to a corresponding first corner portion; a third semiconductor package, which is mounted on an upper surface of the second substrate; a plurality of fixing structures, corresponding pairs of first A corner portion and a second corner portion are assembled in corresponding fixing structures among a plurality of fixing structures; a frame, which is interposed between the first substrate and the second substrate; at least one flexible connector, which connects the second side surface and the fourth side surface; and at least one capacitor, which is connected to the first side surface, wherein the length, width or height of each fixing structure is in the range of 0.1 mm to 200 mm, wherein at least one fixing structure among the plurality of first fixing structures includes a first slot in which one of the first corner portions is assembled and a second slot in which one of the second corner portions is assembled, and wherein the distance between the first slot and the second slot is in the range of 0.1 mm to 100 mm.

[0009] A semiconductor memory module according to some embodiments of the present invention includes: a first substrate including a first corner portion and a first side surface; a first semiconductor package mounted on a lower surface of the first substrate; a second substrate disposed above the first substrate and including a second corner portion and a second side surface corresponding to the first corner portion and the first side surface, respectively; a second semiconductor package mounted on an upper surface of the second substrate; a fixing structure into which the first corner portion and the second corner portion are inserted, the fixing structure fixing a distance between the first substrate and the second substrate; and at least one flexible connector connecting the first side surface and the second side surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Example embodiments will be more clearly understood from the following brief description taken in conjunction with the accompanying drawings.The accompanying drawings represent non-limiting example embodiments as described herein.

[0011] Figure 1 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept.

[0012] Figure 2 is taken along line A-A' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0013] Figure 3 is taken along line BB' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0014] Figure 4 is taken along line C-C' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0015] Figure 5A and Figure 5B is a perspective view of a flexible connector according to an embodiment of the inventive concept.

[0016] Fig. 6A yes Figure 1 A three-dimensional diagram of a semiconductor memory module.

[0017] Figure 6B yes Figure 1 An exploded perspective view of a semiconductor memory module.

[0018] 7A to 7H is a perspective view of a fixing structure according to an embodiment of the inventive concept.

[0019] Figure 8 is taken along line BB' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0020] Fig. 9 is a plan view showing states of components of a semiconductor memory module during a manufacturing process of the semiconductor memory module.

[0021] Fig.10 It is taken along the line A-A' Fig. 9 Cross-sectional view of .

[0022] Fig.11 is a cross-sectional view showing states of components of a semiconductor memory module during a manufacturing process of the semiconductor memory module.

[0023] Fig.12 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept.

[0024] Fig.13 is taken along line BB' according to an embodiment of the present invention. Fig.12 Cross-sectional view of .

[0025] Fig.14 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept.

[0026] Fig.15 is taken along line A-A' according to an embodiment of the present invention. Fig.14 Cross-sectional view of .

[0027] Fig.16 is taken along line BB' according to an embodiment of the present invention. Fig.14 Cross-sectional view of . DETAILED DESCRIPTION

[0028] Hereinafter, in order to explain the inventive concept in detail, embodiments according to the inventive concept will be described with reference to the accompanying drawings. However, the inventive concept can be implemented in many different forms and should not be construed as being limited to the example embodiments set forth herein. These example embodiments are merely examples, and many implementations and variations that do not require the details provided herein are possible. It should also be emphasized that the present disclosure provides the details of alternative examples, but this enumeration of alternative examples is not exhaustive. In addition, any consistency of the details between the examples should not be construed as requiring such details, and it is impractical to list each possible variation for each feature described herein. The language of the claims should be referenced when determining the requirements of the present invention.

[0029] Ordinal numbers such as "first", "second", "third", etc. may simply be used as labels for certain elements, steps, etc. to distinguish these elements, steps, etc. from each other. Terms that are not described using "first", "second", etc. in the specification may still be referred to as "first" or "second" in the claims. In addition, terms referenced with a specific ordinal number (e.g., "first" in a specific claim) may be described elsewhere with a different ordinal number (e.g., "second" in the specification or another claim).

[0030] As can be seen, for example, in the accompanying drawings, items described herein as one may be provided in plural. Therefore, unless the context otherwise requires, it should be understood that descriptions of single items provided in plural may apply to other plural items.

[0031] For ease of description, spatially relative terms such as "below", "under", "down", "above", "up", "top", "bottom", "front", "back", etc. may be used herein to describe positional relationships such as those shown in the figures. It should be understood that the spatially relative terms include different orientations of the device in addition to the orientation shown in the figures. Moreover, these spatially relative terms (such as "above" and "below") as used herein have their ordinary broad meanings, for example, element A can be above element B even if there is no overlap between elements A and B when looking down (just as something in the sky is generally above something on the ground even if it is not directly above).

[0032] It should be understood that when an element is referred to as being "connected" or "coupled" to another element or being "on" another element, it can be directly connected or coupled to or on another element, or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, or as being "contacting" or "in contact with" another element (or any form of the word "contacting"), there are no intervening elements at the point of contact.

[0033] As used herein, components described as being "electrically connected" are configured so that electrical signals can be passed from one component to another (although such electrical signals may be attenuated in strength when passed and may be selectively transmitted). In addition, components that are "directly electrically connected" share a common electrical node through electrical connection made by one or more conductors, such as wires, pads, internal wires, feedthroughs, etc. Thus, components that are directly electrically connected do not include components that are electrically connected through active elements, such as transistors or diodes.

[0034] Figure 1 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept.

[0035] Figure 2 is taken along line A-A' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0036] Figure 3 is taken along line BB' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0037] Reference Figures 1 to 3 , the semiconductor memory module 1000 according to the inventive concept may be, for example, a solid-state drive (SSD), a dual in-line memory module (DIMM), or a small-outline DIMM. The semiconductor memory module 1000 according to the inventive concept includes a housing 500 and a stacking structure ST inserted therein (for example, the housing may accommodate the stacking structure ST). In the semiconductor memory module 1000 according to some of the inventive concepts, the housing 500 may not be included. The stacking structure ST includes a first substrate 100 and a second substrate 200 stacked in sequence. The first substrate 100 and the second substrate 200 may be, for example, a double-sided or multi-layer printed circuit board.

[0038] The first substrate 100 may have a first upper surface 100a and a first lower surface 100b. The first upper conductive pad 101a is disposed on the first upper surface 100a of the first substrate 100. The first lower conductive pad 101b is disposed on the first lower surface 100b of the first substrate 100. The first internal wiring 2 may be disposed in the first substrate 100. The first substrate 100 may have four first corner portions CR1 arranged in a clockwise direction. The first substrate 100 may have a first side surface RS1 and a second side surface RS2 opposite to each other. When viewed in a plan view, the first side surface RS1 and the second side surface RS2 of the first substrate 100 may be recessed toward the center of the first substrate 100.

[0039] The second substrate 200 may have a second upper surface 200a and a second lower surface 200b. The second upper conductive pad 201a is disposed on the second upper surface 200a of the second substrate 200. The second internal wiring 4 may be disposed in the second substrate 200. Although not shown, the second lower conductive pad may also be disposed on the second lower surface 200b of the second substrate 200. The second substrate 200 may have four second corner portions CR2 arranged in a clockwise direction. The second corner portion CR2 is located above the first corner portion CR1, and each second corner portion CR2 may overlap (or correspond to) the corresponding first corner portion CR1. The second substrate 200 may have a third side surface RS3 and a fourth side surface RS4 opposite to each other. When viewed in a plan view, the third side surface RS3 and the fourth side surface RS4 of the second substrate 200 may be recessed toward the center of the second substrate 200. The third side surface RS3 may be disposed on the first side surface RS1 and may overlap with the first side surface RS1 in a vertical direction. The fourth side surface RS4 may be disposed on the second side surface RS2 , and may overlap the second side surface RS2 in a vertical direction.

[0040] The first semiconductor package 20 and at least one second semiconductor package 30 may be mounted on the first lower surface 100b of the first substrate 100. The first semiconductor package 20 may be bonded to some of the first lower conductive pads 101b through the first solder balls 12. The second semiconductor package 30 may be bonded to the other portions of the first lower conductive pads 101b through the second solder balls 14. The third semiconductor package 40 may be disposed on the first upper surface 100a of the first substrate 100. The third semiconductor package 40 may be bonded to the first upper conductive pads 101a through the third solder balls 16.

[0041] The fourth semiconductor package 50 may be mounted on the second upper surface 200a of the second substrate 200. The fourth semiconductor package 50 may be bonded to some of the second upper conductive pads 201a by the fourth solder balls 18. At least one of the first to fourth semiconductor packages 20, 30, 40, and 50 may independently be a system large-scale integration (LSI) chip or a logic circuit chip. Alternatively, the other semiconductor packages of the first to fourth semiconductor packages 20, 30, 40, and 50 may independently be a NAND flash memory chip, a DRAM chip, an SRAM chip, an EEPROM chip, a PRAM chip, an MRAM chip, a ReRAM chip, a high bandwidth memory (HBM) chip, and a hybrid memory cube (HMC) chip. The other semiconductor packages of the first to fourth semiconductor packages 20, 30, 40, and 50 may independently be a micro-electromechanical system (MEMS) device chip or an application-specific integrated circuit (ASIC) chip. At least one of the first to fourth semiconductor packages 20, 30, 40, and 50 may be replaced with a passive element. The passive element may be a capacitor or a resistor.

[0042] The first thermal interface material layer 62 may be between the first semiconductor package 20 and the housing 500. The second thermal interface material layer 64 may be between the second semiconductor package 30 and the housing 500. The third thermal interface material layer 66 may be between the fourth semiconductor package 50 and the housing 500. The thickness of the first thermal interface material layer 62, the second thermal interface material layer 64, and the third thermal interface material layer 66 may be different from each other. For example, the thickness of the first thermal interface material layer 62 may be greater than the thickness of the second thermal interface material layer 64. The density of the first thermal interface material layer 62, the second thermal interface material layer 64, and the third thermal interface material layer 66 may be different from each other. For example, the density of the first thermal interface material layer 62 may be higher than the density of the second thermal interface material layer 64. The first thermal interface material layer 62, the second thermal interface material layer 64, and the third thermal interface material layer 66 may include a thermosetting resin layer. The first thermal interface material layer 62, the second thermal interface material layer 64, and the third thermal interface material layer 66 may also include filler particles dispersed in the thermosetting resin layer. The filler particles may include at least one of silica, alumina, zinc oxide, and boron nitrogen.

[0043] The first frame 90 may be interposed between the first substrate 100 and the second substrate 200. The first frame 90 may maintain a space between the first substrate 100 and the second substrate 200 at a specific distance or more. A portion of the first frame 90 may be inserted into a first groove ( Fig.10Another portion of the first frame 90 may be inserted into a second groove ( H1 ) provided on the second lower surface 200 b of the second substrate 200 . Fig.10 H2). The first frame 90 may be formed of and / or include ceramic, plastic, or metal. The first frame 90 may be spaced apart from the first to fourth semiconductor packages 20, 30, 40, and 50 (e.g., the first frame 90 does not contact the first to fourth semiconductor packages 20, 30, 40, and 50).

[0044] Figure 4 is taken along line C-C' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0045] Reference Figure 1 , Figure 2 and Figure 4 , the semiconductor memory module 1000 according to the present invention may also include at least one capacitor 70. In this example, two capacitors 70 may be provided, but in other examples, more than two capacitors 70 are possible. The capacitor 70 may include two connection terminals 71. The connection terminal 71 may have an "L" shape. The capacitor 70 may be bonded to the recessed first side surface RS1 of the first substrate 100. The connection terminal 71 of the capacitor 70 may be bonded to the first upper conductive pad 101a adjacent to the first side surface RS1. Although not shown, a solder layer may be interposed between the connection terminal 71 and the first upper conductive pad 101a. The capacitor 70 may be disposed in a space provided by the recessed first side surface RS1, and the upper portion of the capacitor 70 may be inserted into a space provided by the recessed third side surface RS3. Due to the recessed first side surface RS1 and the third side surface RS3 of the first substrate 100 and the second substrate 200, the capacitor 70 may not protrude beyond the outermost surfaces of the first substrate 100 and the second substrate 200. Since the capacitor 70 may not protrude beyond the outermost surfaces of the first and second substrates 100 and 200 , the overall size of the semiconductor memory module 1000 may be reduced.

[0046] Figure 5A and 5B is a perspective view of a flexible connector according to an embodiment of the inventive concept.

[0047] Reference Figure 1 , Figure 2 as well as Figure 5A and Figure 5B, the semiconductor memory module 1000 according to the present invention may further include at least one first flexible connector 150. In the present example, two first flexible connectors 150 may be provided. The first flexible connector 150 may connect the recessed second side surface RS2 of the first substrate 100 and the recessed fourth side surface RS4 of the second substrate 200. The first flexible connector 150 may be disposed in a space provided by the recessed second side surface RS2 and the fourth side surface RS4. As a result, the first flexible connector 150 may not protrude beyond the outermost peripheries of the first substrate 100 and the second substrate 200, and therefore, the overall size of the semiconductor memory module 1000 may be reduced. In the present specification, a "flexible connector" may also be referred to as a "flexible substrate."

[0048] like Figure 5A As shown, the first flexible connector 150 may include a first flexible layer 110 and a second flexible layer 140 stacked in sequence, and a flexible wiring 130 interposed therebetween. The flexible wiring 130 may include a metal such as copper. The first flexible layer 110 and the second flexible layer 140 may be formed of and / or include a polyimide or polymer material. Figure 2 The first internal wiring 2 of the first substrate 100 can be connected to the flexible wiring 130 through Figure 2 As another example, the first flexible connector 150 may further include at least one active element 120 disposed between the first flexible layer 110 and the second flexible layer 140 and connected to the flexible wiring 130. The active element 120 may be one of a logic chip, a memory chip, and a processor chip.

[0049] Fig. 6A yes Figure 1 A three-dimensional diagram of a semiconductor memory module. Figure 6B yes Figure 1 An exploded perspective view of a semiconductor memory module.

[0050] Reference Figure 1 , Figure 3 , Fig. 6A and Figure 6B , the first corner portion CR1 of the first substrate 100 and the corresponding second corner portion CR2 of the second substrate 200 may be assembled into the corresponding fixing structure 400. In this example, four fixing structures 400 may be provided. However, the number of the fixing structures 400 in the example is not limited thereto, and may be one or more in other examples. Each of the four corner portions of the stacked structure ST may be assembled into the corresponding fixing structure 400. The fixing structure 400 may surround the stacked structure ST at each of the four corner portions.

[0051] Each of the fixing structures 400 may include a first narrow groove SL1 into which the first corner portion CR1 is assembled and a second narrow groove SL2 into which the second corner portion CR2 corresponding to the first corner portion CR1 is assembled. The fixing structure 400 may cooperate with the first corner portion CR1 of the first substrate 100 and the corresponding second corner portion CR2 of the second substrate 200, and thus, the distance between the first substrate 100 and the second substrate 200 may be fixed to be constant by the fixing structure 400. The fixing structure 400 may have a single-layer or multi-layer structure formed by and / or including at least one of plastic, fiber, rubber, sponge, polyurethane, carbon material, ceramic, metal and porous material. The fixing structure 400 may also be referred to as a "clip". The fixing structures 400 may each independently have a length, width and / or height in the range of 0.1 mm to 200 mm. The distance between the first narrow groove SL1 and the second corner portion CR2 ( Fig. 7A The distance (or spacing) between the center of the first narrow groove SL1 or the center of the second corner portion CR2 may be in the range of 0.1 mm to 100 mm.

[0052] Due to the elastic restoring force of the first flexible connector 150, the first flexible connector 150 may apply a downward force to the first substrate 100 and an upward force to the second substrate 200. However, the first flexible connector 150 cannot be deployed within the housing 500. Therefore, the first semiconductor package 20, the second semiconductor package 30, and the fourth semiconductor package 50 mounted on the first substrate 100 and the second substrate 200 may be pressed toward the housing 500 by the elastic restoring force of the first flexible connector 150. The elastic restoring force of the first flexible connector 150 may cause physical stress applied to the first semiconductor package 20, the second semiconductor package 30, and the fourth semiconductor package 50. The physical stress may be transferred to the first solder ball 12, the second solder ball 14, and the fourth solder ball 18 between the first semiconductor package 20, the second semiconductor package 30, and the fourth semiconductor package 50. As a result, solder ball cracks (or solder joint cracks) or pattern cracks may occur in the PCB area. Therefore, the reliability of the semiconductor memory module may be deteriorated.

[0053] However, in the present inventive concept, the fixing structure 400 can suppress the elastic restoring force of the first flexible connector 150. Therefore, the physical stress applied to the first solder ball 12, the second solder ball 14, and the fourth solder ball 18 can be dispersed, alleviated, and / or reduced, thereby preventing the solder balls from being broken. Therefore, the reliability of the semiconductor memory module can be improved by the fixing structure 400. In addition, according to the present inventive concept, since the corner portions CR1 and CR2 of the stacked structure ST inserted into the fixing structure 400 are generally not the areas where the semiconductor packages 20 to 50 are disposed, space utilization is effective. Therefore, the described integrated semiconductor memory module 1000 can provide an improved semiconductor memory module.

[0054] 7A to 7H is a perspective view of a fixing structure according to an embodiment of the inventive concept.

[0055] Reference Fig. 7A , when viewed in a plan view, the fixing structure 400 may have an "L" shape or have edges with right angles. The fixing structure 400 may further include a recessed portion RR between the first slot SL1 and the second slot SL2. All side surfaces of the fixing structure 400 may be straight (eg, straight).

[0056] Alternatively, refer to Figure 7B , one side surface 400S of the fixing structure 400 may be rounded. When viewed in a plan view, the fixing structure 400 may have an edge of a curved shape. The curved shape may be bent inwardly toward the fixing structure 400.

[0057] Alternatively, refer to Figure 7C , the fixing structure 400 may have an “I” shape extending in the longitudinal direction. When viewed in a plan view, the slots such as the first slot SL1 and the second slot SL2 may extend linearly without changing the direction.

[0058] Alternatively, refer to Fig.7D , when viewed in a plan view, the fixing structure 400 may have an "L" shape. The fixing structure 400 may have a single slot. For example, the fixing structure may not include the first slot SL1 (eg, the first slot SL1 is not included).

[0059] Alternatively, refer to Fig. 7E , when viewed in a plan view, the fixing structure 400 may have an “L” shape. The fixing structure 400 may not include the second slot SL2 (eg, the second slot SL21 is not included).

[0060] Alternatively, refer to Figure 7F , when viewed in a plan view, the fixing structure 400 may have a rectangular shape.

[0061] Alternatively, refer to Figure 7G , when viewed in a plan view, the fixing structure 400 may have a right triangle shape.

[0062] Alternatively, refer to Figure 7H The fixing structure 400 has a structure in which the first and second slots SL1 and SL2 are merged with the recessed portion RR. That is, the first corner portion CR1 of the first substrate 100 and the corresponding second corner portion CR2 of the second substrate 200 may be inserted into the recessed portion RR.

[0063] Figure 8 is taken along line BB' according to an embodiment of the present invention. Figure 1 Cross-sectional view of .

[0064] Reference Figure 8 In the semiconductor memory module 1001 according to the present example, the fixing structure 400 may be formed of a metal or a conductive material. The first substrate 100 may further include a first lower wiring 101c disposed on the first lower surface 100b and in contact with the fixing structure 400. The second substrate 200 may further include a second upper wiring 201c disposed on the second upper surface 200a and in contact with the fixing structure 400. The fixing structure 400 may electrically connect the first lower wiring 101c of the first substrate 100 and the second upper wiring 201c of the second substrate 200. One of the first semiconductor packages 20 may be electrically connected to one of the fourth semiconductor packages 50 through one of the fixing structures 400. The second semiconductor package 30 may be electrically connected to another of the fourth semiconductor packages 50 through another of the fixing structures 400. Other structures may be the same as those described with reference to FIG. Figures 1 to 7H The structures are the same or similar to those described.

[0065] Fig. 9 It is shown that in the manufacture of Figure 1 A plan view showing states of components of a semiconductor memory module during a process of manufacturing the semiconductor memory module is shown. Fig.10 It is taken along the line A-A' Fig. 9 Cross-sectional view of . Fig.11 is a cross-sectional view showing states of components of a semiconductor memory module during a manufacturing process of the semiconductor memory module.

[0066] Reference Fig. 9 and Fig.10, prepare a first substrate 100. The first substrate 100 may have a first upper surface 100a and a first lower surface 100b. The first upper conductive pad 101a is mounted on the first upper surface 100a of the first substrate 100. The first lower conductive pad 101b is mounted on the first lower surface 100b of the first substrate 100. The first groove H1 may be formed in the first upper surface 100a of the first substrate 100. The first internal wiring 2 may be provided in the first substrate 100. The first substrate 100 may have four first corner portions CR1 arranged in a clockwise direction. The first substrate 100 may have a first side surface RS1 and a second side surface RS2 opposite to each other. When viewed in a plan view, the first side surface RS1 and the second side surface RS2 of the first substrate 100 may be recessed toward the center of the first substrate 100.

[0067] The first semiconductor package 20 is mounted on the first lower surface 100b of the first substrate 100, with the first solder ball 12 interposed therebetween. The second semiconductor package 30 is mounted on the first lower surface 100b of the first substrate 100, with the second solder ball 14 interposed therebetween. The third semiconductor package 40 is mounted on the first upper surface 100a of the first substrate 100, with the third solder ball 16 interposed therebetween. The third semiconductor package 40 may be bonded to other portions of the first upper conductive pad 101a. The capacitor 70 is connected to the first side surface RS1 of the first substrate 100.

[0068] Prepare the second substrate 200. The second substrate 200 may have a second upper surface 200a and a second lower surface 200b. Fig.10 The second substrate 200 observed in the state is turned over so that the second upper surface 200a faces downward and the second lower surface 200b faces upward. The second upper conductive pad 201a is provided on the second upper surface 200a of the second substrate 200. The second internal wiring 4 may be provided in the second substrate 200. Although not shown, a second lower conductive pad may also be provided on the second lower surface 200b of the second substrate 200. The second groove H2 may be formed in the second lower surface 200b of the second substrate 200. The second substrate 200 may have four second corner portions CR2 arranged in a clockwise direction.

[0069] In components such as Fig.10In the case where the semiconductor memory module 1000 is in place as shown in the state of FIG. 1 , the semiconductor memory module 1000 may be folded so that the first upper surface 100a of the first substrate 100 faces the second lower surface 200b of the second substrate 200. After the second substrate 200 is folded on the first substrate 100, each of the second corner portions CR2 may be located above the corresponding first corner portion CR1 and may vertically overlap (or correspond to) the corresponding first corner portion CR1. The second substrate 200 may have a third side surface RS3 and a fourth side surface RS4 opposite to each other. When viewed in a plan view, the third side surface RS3 and the fourth side surface RS4 of the second substrate 200 may be recessed toward the center of the second substrate 200. The third side surface RS3 may be disposed above the first side surface RS1 and may vertically overlap the first side surface RS1. The fourth side surface RS4 may be disposed above the second side surface RS2 and may vertically overlap the second side surface RS2.

[0070] The fourth semiconductor package 50 is mounted on the second upper surface 200 a of the second substrate 200 with the fourth solder balls 18 interposed therebetween. The second side surface RS2 of the first substrate 100 is connected to the fourth side surface RS4 of the second substrate 200 through the first flexible connector 150 .

[0071] The first thermal interface material layer 62 is formed on the first semiconductor package 20. The second thermal interface material layer 64 is formed on the second semiconductor package 30. The third thermal interface material layers 66 are formed on the fourth semiconductor packages 50, respectively.

[0072] Reference Fig.11 , the first frame 90 is located on the first upper surface 100a of the first substrate 100. The first frame 90 is inserted into the first groove H1. Then, the first flexible connector 150 is bent to place the second substrate 200 on the first substrate 100, as shown in FIG. Figure 2 and Figure 5B In this case, the first frame 90 may be inserted into the second groove H2 of the second lower surface 200b of the second substrate 200. As a result, a stacked structure ST may be formed. Figure 5B As shown, the fixing structure 400 is assembled into the corner portions CR1 and CR2 of the stack structure ST. In addition, the stack structure ST may be inserted into the case 500.

[0073] Fig.12 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept. Fig.13 is taken along line BB' according to an embodiment of the present invention. Fig.12 A cross-sectional view of the . Fig.12 The cross section can be Figure 2 the same or similar.

[0074] Reference Fig.12 and Fig.13 , in the semiconductor memory module 1002 according to the present example, two fixing structures 400 may be provided.

[0075] Two first corner portions CR1 of the first substrate 100 and corresponding second corner portions CR2 of the second substrate 200 may be assembled into the fixing structure 400. In this example, for the first substrate 100, two first corner portions CR1 adjacent to the first side surface RS1 and opposite to the second side surface RS2 on which the first flexible connector 150 is disposed may be assembled into the fixing structure 400. The remaining first corner portions CR1 of the first substrate 100 are not assembled into the fixing structure 400. For the second substrate 200, two second corner portions CR2 adjacent to the third side surface RS3 and opposite to the fourth side surface RS4 on which the first flexible connector 150 is disposed may be assembled into the fixing structure 400. The remaining second corner portions CR2 of the second substrate 200 are not assembled into the fixing structure 400. Other structures may be the same as those described with reference to FIG. Figures 1 to 8 The structures are the same or similar to those described.

[0076] Fig.14 is a plan view of a semiconductor memory module according to an embodiment of the inventive concept.

[0077] Fig.15 is taken along line A-A' according to an embodiment of the present invention. Fig.14 Cross-sectional view of .

[0078] Fig.16 is taken along line BB' according to an embodiment of the present invention. Fig.14 Cross-sectional view of .

[0079] Reference Figures 14 to 16 According to the present example, the semiconductor memory module 1003 may not include reference Figure 1 , Figure 2 and Figure 4 The semiconductor memory module 1003 according to the present example may further include a third substrate 300 disposed under the first substrate 100, a second flexible connector 250, and a second frame 190. The third substrate 300 may be, for example, a double-sided or multi-layer printed circuit board.

[0080] The third substrate 300 may have a third upper surface 300a and a third lower surface 300b. The third internal wiring 6 may be provided in the third substrate 300. The third substrate 300 may have four third corner portions CR3 arranged in a clockwise direction. The third substrate 300 may have a fifth side surface RS5 and a sixth side surface RS6 opposite to each other. When viewed in a plan view, the fifth side surface RS5 and the sixth side surface RS6 of the third substrate 300 may be recessed toward the center of the third substrate 300.

[0081] The fifth semiconductor package 80 and at least one sixth semiconductor package 82 may be mounted on the third lower surface 300b of the third substrate 300 using solder balls. The seventh semiconductor package 84 may be mounted on the third upper surface 300a of the third substrate 300 using solder balls.

[0082] Each of the fifth to seventh semiconductor packages 80, 82, and 84 may be independently a system large-scale integration (LSI) chip or a logic circuit chip, or may be a memory device chip such as a NAND flash memory chip, a DRAM chip, an SRAM chip, an EEPROM chip, a PRAM chip, an MRAM chip, a ReRAM chip, a high bandwidth memory (HBM) chip, a hybrid memory cube (HMC) chip, etc., or may be a micro-electromechanical system (MEMS) device chip or an application-specific integrated circuit (ASIC). At least one of the fifth to seventh semiconductor packages 80, 82, and 84 may be replaced with a passive element. The passive element may be a capacitor or a resistor.

[0083] The fourth thermal interface material layer 86 may be interposed between the fifth semiconductor package 80 and the housing 500 . The fifth thermal interface material layer 88 may be interposed between the sixth semiconductor package 82 and the housing 500 .

[0084] The second frame 190 may be interposed between the first substrate 100 and the third substrate 300. The second frame 190 may maintain a gap of at least a certain distance between the first substrate 100 and the third substrate 300. A portion of the second frame 190 may be inserted into the first substrate 100 and the third substrate 300.

[0085] The second flexible connector 250 may connect the concave first side surface RS1 of the first substrate 100 to the concave fifth side surface RS5 of the third substrate 300. The structure of the second flexible connector 250 may be similar to that of the reference numeral 254. Figure 5A or Figure 5B The first flexible connector 150 described above is the same or similar. The second flexible connector 250 may be provided in plural numbers.

[0086] The corner portions CR1, CR2, and CR3 of the stacked structure ST may be assembled into the fixed structure 400. The first corner portion CR1, the second corner portion CR2, and the third corner portion CR3 corresponding to each other may be assembled into the fixed structure 400. In this example, four fixed structures 400 may be provided. The four corner portions of the stacked structure ST may be assembled into the fixed structure 400. Each of the fixed structures 400 may include a first narrow groove SL1 into which the first corner portion CR1 is inserted, a second narrow groove SL2 into which the second corner portion CR2 corresponding to the first corner portion CR1 is inserted, and a third narrow groove SL3 into which the third corner portion CR3 corresponding to the first corner portion CR1 is inserted. Other configurations may be the same as those described with reference to FIG. Figures 1 to 8 The constructions are the same or similar to those described.

[0087] In a semiconductor memory module according to the present invention, at least one corner portion of a stack structure including a first substrate and a second substrate stacked on each other is inserted into a fixing structure. The fixing structure can suppress the elastic restoring force of a flexible connector connecting the side surfaces of the substrates, and can fix the first substrate and the second substrate to be separated from each other by at least a certain distance. Therefore, the solder balls under the semiconductor packages mounted on the first substrate and the second substrate can be prevented from being broken. Therefore, the reliability of the bump solder joint can be improved, thereby improving the reliability of the semiconductor memory module.

[0088] Furthermore, since the corner portion of the substrate according to the inventive concept can be inserted into the fixing structure, an area for disposing a semiconductor package can be omitted, so space utilization is effective. Therefore, an improved integrated semiconductor memory module can be provided.

[0089] Although the embodiments are described above, it will be appreciated by those skilled in the art that many modifications and variations may be made without departing from the spirit and scope of the inventive concept defined in the appended claims. Therefore, the exemplary embodiments of the inventive concept should be considered in all aspects to be illustrative and not restrictive, and the spirit and scope of the inventive concept are indicated by the appended claims. Figures 1 to 16 The embodiments may be combined with each other.

Claims

1. A semiconductor memory module, comprising: A first substrate including a first corner portion; a first semiconductor package mounted on a lower surface of the first substrate; a second substrate disposed above the first substrate and comprising a second corner portion corresponding to the first corner portion; a second semiconductor package mounted on an upper surface of the second substrate; as well as A fixing structure in which the first corner portion and the second corner portion are assembled.

2. The semiconductor memory module according to claim 1, in, The first substrate includes a first plurality of corner portions, the first plurality of corner portions including the first corner portion, wherein the second substrate includes a second plurality of corner portions, the second plurality of corner portions includes the second corner portion, wherein the fixing structure is a first fixing structure, and the semiconductor memory module includes a plurality of fixing structures, the plurality of fixing structures including the first fixing structure, and Wherein, each of the plurality of fixing structures physically supports a corresponding corner portion of the first plurality of corner portions and the second plurality of corner portions.

3. The semiconductor memory module according to claim 1, wherein: The first substrate has a first side surface, wherein the second substrate has a second side surface disposed on the first side surface, and The semiconductor memory module further includes at least one first flexible connector connecting the first side surface and the second side surface.

4. The semiconductor memory module according to claim 3, wherein: Each of the first side surface and the second side surface has a recessed portion, and Wherein, the first flexible connector is arranged in the recessed portion.

5. The semiconductor memory module according to claim 3, wherein: The first flexible connector comprises: A first flexible layer and a second flexible layer stacked sequentially; a first flexible wiring interposed between the first flexible layer and the second flexible layer; and An active element is interposed between the first flexible layer and the second flexible layer and connected to the first flexible wiring.

6. The semiconductor memory module according to claim 3, further comprising: A third substrate, disposed below the first substrate; a third semiconductor package mounted on the lower surface of the third substrate; as well as a second flexible connector connecting the third substrate and the first substrate, wherein the first substrate has a third side surface opposite to the first side surface, The third substrate has a fourth side surface located below the third side surface, and Wherein, the second flexible connector connects the third side surface and the fourth side surface.

7. The semiconductor memory module according to claim 1, wherein: The fixing structure has a multilayer structure of at least one of plastic, fiber, rubber, sponge, polyurethane, carbon material, ceramic, metal and porous material.

8. The semiconductor memory module according to claim 1, in, The fixing structure is formed of a conductive material, Wherein, the semiconductor memory module further includes: a first conductive pattern disposed on a lower surface of the first substrate and electrically connecting the fixed structure with one of the first semiconductor packages; and a second conductive pattern disposed on an upper surface of the second substrate, and The fixing structure is electrically connected to one of the second semiconductor packages.

9. The semiconductor memory module according to claim 1, wherein: When viewed in a plan view, the fixing structure has an "L" shape, an "I" shape, a triangle or a quadrilateral.

10. The semiconductor memory module according to claim 1, wherein: The fixed structure comprises: a first slot into which the first corner portion of the first substrate is inserted; and A second narrow groove into which the second corner portion of the second substrate is inserted.

11. The semiconductor memory module according to claim 1, in, The first substrate includes a first side recessed portion, Wherein, the second substrate comprises a second side recessed portion corresponding to the first side recessed portion, The semiconductor memory module further includes a first capacitor, which is disposed in the first side recess and connected to the first substrate, and Wherein, the upper surface of the first capacitor is inserted into the second side recess.

12. The semiconductor memory module according to claim 1, further comprising: a housing accommodating the first substrate, the first semiconductor package, the second substrate, the second semiconductor package and the fixing structure; a first thermal interface material layer disposed between the first semiconductor package and the housing; as well as A second thermal interface material layer is disposed between the second semiconductor package and the housing.

13. The semiconductor memory module according to claim 12, wherein: The density of the first thermal interface material layer is different from the density of the second thermal interface material layer.

14. The semiconductor memory module according to claim 12, wherein: The thickness of the first thermal interface material layer is different from the thickness of the second thermal interface material layer.

15. The semiconductor memory module according to claim 1, further comprising: a frame interposed between the first substrate and the second substrate; as well as A third semiconductor package is mounted on the upper surface of the first substrate and is spaced apart from the frame.

16. A semiconductor memory module, comprising: case; as well as a stacking structure housed in the housing, Wherein, the stacking structure comprises: A first substrate including a plurality of first corner portions and having a first side surface and a second side surface; a first semiconductor package mounted on a lower surface of the first substrate; a second semiconductor package mounted on an upper surface of the first substrate; a second substrate disposed above the first substrate, the second substrate comprising a plurality of second corner portions, each of the second corner portions corresponding to a corresponding first corner portion, and the second substrate having a third side surface and a fourth side surface; a third semiconductor package mounted on the upper surface of the second substrate; a plurality of fixing structures, wherein corresponding pairs of the first corner portions and the second corner portions are assembled in corresponding fixing structures among the plurality of fixing structures; a frame interposed between the first substrate and the second substrate; at least one flexible connector connecting the second side surface and the fourth side surface; and at least one capacitor connected to the first side surface, wherein the length, width or height of each of the fixing structures is in the range of 0.1 mm to 200 mm, Wherein, at least one of the plurality of fixed structures comprises: a first slot in which one of the first corner portions fits; and a second slot in which one of the second corner portions fits, and Wherein, the distance between the first slot and the second slot is in the range of 0.1 mm to 100 mm.

17. The semiconductor memory module according to claim 16, in, The first side surface and the second side surface are recessed toward the center of the first substrate, Wherein, the third side surface and the fourth side surface are recessed toward the center of the second substrate.

18. The semiconductor memory module according to claim 16, wherein: When viewed in a plan view, each of the fixing structures has an "L" shape, an "I" shape, a triangle, or a quadrilateral.

19. A semiconductor memory module, comprising: a first substrate including a first corner portion and a first side surface; a first semiconductor package mounted on a lower surface of the first substrate; a second substrate disposed above the first substrate and comprising a second corner portion and a second side surface corresponding to the first corner portion and the first side surface, respectively; a second semiconductor package mounted on an upper surface of the second substrate; a fixing structure, into which the first corner portion and the second corner portion are inserted, and wherein the fixing structure fixes a distance between the first substrate and the second substrate; as well as At least one flexible connector connects the first side surface and the second side surface.

20. The semiconductor memory module according to claim 19, in, The first substrate includes a first side recessed portion, Wherein, the second substrate comprises a second side recessed portion corresponding to the first side recessed portion, The semiconductor memory module further includes a first capacitor, which is disposed in the first side recess and connected to the first substrate, and Wherein, the upper surface of the first capacitor is inserted into the second side recess.

Images