This application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2022-0106453 filed in the Korean Intellectual Property Office on Aug. 24, 2022, the entire contents of which are incorporated herein by reference.
The present disclosure relates to module boards and semiconductor modules including the same.
A module board used for a semiconductor module has tab terminals on the edge of a substrate. The tab terminals facilitate an electrical signal connection and are inserted into a socket and are electrically connected to electronic components, including the socket.
For environmental reasons, efforts are being made to reduce gas discharge generated in the manufacturing process of semiconductor modules. In relation to this, cooling of semiconductor modules through external ventilation is being utilized to reduce power consumption. Unfortunately, corrosion may occur in corrodible materials such as silver (Ag) and copper (Cu) due to corrosive material that can inflow during external ventilation.
In particular, tab terminals of conventional module boards have regions that may be vulnerable to corrosion. Defects, such as wire pattern breakage, may occur due to Cu corrosion in these regions.
One aspect is to provide module boards that may prevent corrosion at the pattern neck, which is a weak region susceptible to corrosion at a tab terminal.
Another aspect is to provide semiconductor modules with improved life-span reliability by preventing pattern defects caused by corrosion.
A module board according to an embodiment includes a substrate having a surface, a wire pattern on the substrate surface, a protection layer on the substrate surface and configured to expose an edge region of the substrate surface. A plurality of tab terminals are on the edge region in adjacent, spaced apart relationship and are connected to the wire pattern. Each tab terminal has a width that is larger than a width of a portion of the wire pattern to which each tab terminal is connected. Each tab terminal includes a pattern layer, and the protection layer is on a portion of the pattern layer at a region where each tab terminal is connected to the wire pattern, and a plating layer is on a remaining portion of the pattern layer.
The plating layer may include a first plating layer on the pattern layer and a second plating layer on the first plating layer.
The boundary line between the protection layer and the plating layer may extend in the width direction of each of the tab terminals.
The protection layer may include a first protection layer on the wire pattern, and a second protection layer on the region where each tab terminal is connected to the wire pattern.
Each tab terminal may include an overlapping region where the protection layer extends over a portion of the plating layer.
In the overlapping region, the protection layer may be on a portion of the second plating layer.
In the overlapping region, the protection layer may be on a portion of the first plating layer.
At each tab terminal, an end of the protection layer may abut an end of the second plating layer.
A width of each tab terminal in a region where each tab terminal is connected to the wire pattern may gradually increase in a direction toward a free end of the substrate edge region.
For each tab terminal, the protection layer may conform to a shape of a region where each tab terminal is connected to the wire pattern.
The pattern layer may include copper, and the plating layer may include at least one of nickel and gold.
A module board according to an embodiment includes a substrate having a surface, a wire pattern on the substrate surface, a protection layer on the wire pattern, and a plurality of tab terminals on an edge portion of the substrate surface in adjacent, spaced apart relationship. The tab terminals are connected to the wire pattern and each tab terminal has a width that is larger than a width of a portion of the wire pattern to which each tab terminal is connected. The protection layer is on a portion of each tab terminal at a region where each tab terminal is connected to the wire pattern, and a plating layer is on a remaining portion of each tab terminal.
Each tab terminal includes a pattern layer and the plating layer is on a portion of the pattern layer.
The pattern layer may be completely covered by the protection layer and the plating layer.
The boundary line between the protection layer and the plating layer may extend in a width direction of each of the tab terminals.
The protection layer may include a first protection layer on the wire pattern, a second protection layer on the region where each tab terminal is connected to the wire pattern, and the second protection layer may be on the first protection layer and the plating layer.
Each tab terminal may include an overlapping region where the protection layer extends over the plating layer. The plating layer may include a first plating layer on the pattern layer and a second plating layer on the first plating layer. The protection layer may be on the second plating layer in the overlapping region.
Each tab terminal may include an overlapping region in which the protection layer extends over the plating layer. The plating layer may include a first plating layer on the pattern layer and a second plating layer on the first plating layer. The protection layer may be on the first plating layer in the overlapping region.
A semiconductor module according to an embodiment includes a module board having a substrate that includes a surface and a wire pattern on the substrate surface. A protection layer covers the wire pattern on the substrate surface, and a plurality of tab terminals are on an edge region of the substrate surface in adjacent, spaced apart relationship. The tab terminals are connected to the wire pattern. A plurality of semiconductor elements are on the substrate surface of the module board and are connected to the wire pattern. Each tab terminal has a width that is larger than a width of a portion of the wire pattern to which each tab terminal is connected. The protection layer is on a portion of each tab terminal and a plating layer is on a remaining portion of each tab terminal.
The protection layer is on each tab terminal at a region where each tab terminal is connected to the wire pattern, and a boundary between the protection layer and the plating layer may extend in a width direction of each of the tab terminals.
According to an embodiment, by covering the pattern neck of the tab terminal with the protection layer, it is possible to prevent corrosion of the pattern neck.
In addition, life-span reliability may be increased by preventing pattern defects caused by corrosion.
Hereinafter, an embodiment will be described more fully with reference to the accompanying drawings for a person of ordinary skill to easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the scope of the present invention.
The drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.
Because the size and thickness of each configuration shown in the drawings are arbitrarily shown for better understanding and ease of description, the present invention is not limited thereto.
Throughout the specification, when it is described that a part is “connected (in contact with, coupled)” to another part, the part may be “directly connected” to the other element or “connected” to the other part through a third part. In addition, unless explicitly described to the contrary, the word “comprise”, and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. Further, in the specification, the word “on” or “above” means positioned on or below the object portion, and does not necessarily mean positioned on the upper side of the object portion based on a gravitational direction.
Further, throughout the specification, the phrase “in a plan view” means when an object portion is viewed from above, and the phrase “in a cross-sectional view” means when a cross-section taken by vertically cutting an object portion is viewed from the side.
Hereinafter, a module board according to an embodiment and a semiconductor module including the same will be described with reference to accompanying drawings.
Referring to
According to an embodiment, the semiconductor module 100 may be a memory module, and for example, may be at least one memory module selected from a DIMM (Dual Inline Memory Module), a SO-DIMM (Small Outline Dual Inline Memory Module), or an Unbuffered-DIMM or FB-DIMM (Fully Buffered Dual Inline Memory Module), but is not limited thereto.
The semiconductor elements 120 may be provided on the surface of the module board 110 and connected to a wire pattern formed on the surface of the module board 110. According to an embodiment, the semiconductor element 120 may include a memory element, for example, at least one memory element selected from a DRAM (Dynamic Random Access Memory), an SRAM (Static Random Access Memory), a PRAM (Phase Random Access Memory), an RRAM (Resistive Random Access Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or a flash memory, but is not limited thereto.
The module board 110 includes a substrate S (
The substrate S may have a wire pattern 140 on the surface. In addition, although not shown in the drawing, a plurality of stacked wiring layers and a via may be included. For example, the substrate S could have an approximately rectangular shape with four corners, but is not limited thereto.
The protection layer P is a layer to protect the wire pattern 140 by covering the surface of the substrate S, and covers the wire pattern 140 so that the wire pattern 140 is not exposed.
According to an embodiment, the protection layer P may include a PSR (Photo Solder Resist). For example, it may be formed through a process of printing a PSR ink on the surface of the substrate S before mounting the semiconductor elements 120. The protection layer P may be formed in a region where an element component is not mounted.
According to an embodiment, the protection layer P may be formed such that one edge region of the substrate S surface is exposed. That is, the protection layer P may not be formed in one edge region in which the tab terminal 130, which is described below, is positioned. Accordingly, one edge region of the substrate S surface may be exposed from the protection layer P.
A plurality of tab terminals 130 are arranged on one edge region of the substrate surface where the protection layer P is not formed. A plurality of tab terminals 130 are parts that are configured to be fastened to a socket of an electronic part to be electrically connected to the electronic part and may be arranged on both surfaces of the substrate S. Also, since a plurality of tab terminals 130 must be connected to the socket, they may be exposed from the protection layer P. A plurality of tab terminals 130 may be connected to a wire pattern 140 formed on the surface of the substrate S.
Referring to
Since each tab terminal 130 is directly connected to the wire pattern 140 while having the larger width than the wire pattern 140, the tab terminal 130 may include a pattern neck 135 that is a connection part with the wire pattern 140. The pattern neck 135 is a portion with a width that is less than the width W of the tab terminal 130, which may be vulnerable to damage. For example, a corrosion-causing gas may be penetrated into the interface between a plating layer PL covering a pattern layer 130-1 described below and the protection layer P, so that the pattern layer 130-1 of the pattern neck 135 having the relatively small width may be easily corroded and broken. Thus, according to an embodiment, since one region (the region far from the substrate edge) including the connection part with the wire pattern at the tab terminal 130 is covered by the protection layer P, the pattern neck 135 of the vulnerable part may be protected by the protection layer P.
As shown in
Referring to
The pattern layer 130-1 is a layer that is directly connected to the wire pattern 140 and may be extended from the wire pattern 140. The pattern layer 130-1 may be formed on the substrate S in the same process as the wire pattern 140 and may be integral to the wire pattern 140. It may also be made of the same material as the wire pattern 140 and may include one metal or an alloy of the metal. For example, the pattern layer 130-1 may include copper (Cu).
The plating layer PL is a layer plated on the pattern layer 130-1 and covers the region not covered by the protection layer P at the tab terminal 130. That is, the plating layer PL covers the region A2 that is exposed from the protection layer P on the tab terminal 130.
The plating layer PL may include a first plating layer 130-2 on the pattern layer 130-1, and a second plating layer 130-3 on the first plating layer 130-2. The plating layer PL may be formed by plating the upper part of the pattern layer 130-1, for example, the first plating layer 130-2 and the second plating layer 130-2 may be sequentially formed over the pattern layer 130-1 through a commonly known plating process such as the electroplating process. The plating layer PL is made up of a metal with very low resistance, which allows the tab terminal 130 to have low resistance. According to an embodiment, the plating layer PL may include at least one of nickel (Ni) and gold (Au). For example, the first plating layer 130-2 may be plated with nickel (Ni), and the second plating layer 130-3 may be plated with gold (Au).
According to an embodiment, the pattern layer 130-1 may be completely covered by the protection layer P and the plating layer PL so that there is no region exposed to the outside. Accordingly, it is possible to prevent the penetration of the corrosion-causing gas into the interface of the plating layer PL and the protection layer P. Hereinafter, various forms of the embodiment will be described in conjunction with the drawings.
According to a first embodiment, the pattern layer 130-1 is covered by the protection layer P and the plating layer PL, and referring to
In the case of the first embodiment, like a manufacturing process of a general flexible printed circuit (FPC), the wire pattern 140 and the pattern layer 130-1 are formed on the substrate S, the protection layer P is then formed to cover one region of the wire pattern 140 and the pattern layer 130-1, and then the upper part of the exposed region A2 of the pattern layer 130-1 is plated with the first plating layer 130-2 and the second plating layer 130-3 through the plating process.
As shown in
In the case of the second embodiment, the wire pattern 140 and the pattern layer 130-1 may be formed on the substrate S, and then the first protection layer P1 may be formed to cover the wire pattern 140, the upper part of the exposed region A2 of the pattern layer 130-1 is plated with the first plating layer 130-2 and the second plating layer 130-3 through the plating process, and then the part between the first protection layer P1 and the second plating layer 130-2 may be plated with the second protection layer P2, thereby being manufactured.
The second protection layer P2 may be formed of the same material as the first protection layer P1. According to an embodiment, the second protection layer P2 may be formed of PSR. However, it is not limited thereto, and the second protection layer P2 may be made of a resin and may include an epoxy resin, a thermosetting resin, a UV-curing resin, and an insulating material.
As shown in
In the case of the third embodiment, the wire pattern 140 and the pattern layer 130-1 are formed on the substrate S (referring to
As shown in
In the case of the fourth embodiment, the wire pattern 140 and the pattern layer 130-1 are formed on the substrate S, and then the first plating layer 130-2 is formed on the pattern layer 130-1 (referring to
Hereinafter, a modified form of the tab terminal portion and the protection layer from the various embodiments described above will be described as an example.
As mentioned above, each tab terminal 130 is extended towards the edge of the substrate and may have the form of an approximately rectangular shape. Referring to
For example, as shown in
Further, as shown in
According to an embodiment, the shape of the protection layer P in the covered region (A1, referring to
While this disclosure has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
Number | Date | Country | Kind |
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10-2022-0106453 | Aug 2022 | KR | national |