CN1421920A - Substrate on which passive components can be placed - Google Patents

A base plate capable of setting passive components comprises a core layer, a chip connecting area for connecting a chip and a lead forming area which is annularly arranged outside the chip bonding area and is used for arranging a plurality of conductive traces are formed on the core layer, and a solder mask layer is laid on the lead forming area to make the conductive traces hermetically isolated from the outside; the lead forming area is also provided with at least one welding pad for welding the passive component and exposing the anti-welding agent layer, at least the central part of the welding pad is provided with a central slot, when welding agent is coated on the welding pad to weld the passive component, the formation of the central slot can cause the surface tension of the welding agent to concentrate towards the central slot to generate cohesive force, thereby pulling the passive component to be positioned on the central slot of the welding pad without deviation, and simultaneously, the formation of the central slot can cause the welding agent positioned on the part to generate downward pulling force which is enough to pull the passive component on the welding agent downwards to ensure that no tombstone problem occurs after the welding of the passive component and the welding pad is finished.

可设置无源组件的基板Substrate on which passive components can be placed

技术领域technical field

本发明涉及一种用于半导体封装件的基板，尤指一种可供芯片与无源组件同时设置其上的半导体封装件用基板。The invention relates to a substrate for a semiconductor package, in particular to a substrate for a semiconductor package on which a chip and a passive component can be arranged simultaneously.

背景技术Background technique

电子产品在高功能及高速化的趋势下，渐需在半导体封装件(Semicoductor Package)上整合有如电容、电阻或电感等无源组件，以提升或稳定电子产品的电性及功能。然而，伴随着电子产品轻薄短小化的需求，半导体封装件中所包覆的基板上可供无源组件设置的面积随而减少。因而，如何在有限的面积上设置足够的无源组件以配合产品设计上的需求，而同时不致影响基板上的线路布局性(Routability)，乃成半导体业界亟须解决的一大课题。Under the trend of high-performance and high-speed electronic products, it is gradually necessary to integrate passive components such as capacitors, resistors, or inductors on the semiconductor package to improve or stabilize the electrical properties and functions of electronic products. However, along with the demand for thinner, lighter and smaller electronic products, the area available for disposing passive components on the substrate covered by the semiconductor package is reduced accordingly. Therefore, how to arrange enough passive components in a limited area to meet the requirements of product design without affecting the circuit layout (Routability) on the substrate has become a major issue that the semiconductor industry needs to solve urgently.

并且，无源组件一般通过涂布于基板上用以提供无源组件焊接的焊垫(Solder Pad)上的焊药(Solder Paste)而电性连接至基板，而焊接的手段一般则采用回熔焊接(Reflow Soldering)的方式。在回熔焊接进行时，焊药受热所产生的表面张力的变化往往会令体积逐渐微小化的无源组件产生组件浮动(Passive Float)现象，无源组件一旦发生位置偏移，在极有限的空间中，遂易接触至邻近的组件或焊线而造成短路的问题；而另一无源组件在回焊作业中常发生的问题在于立碑(Tombstone)现象的产生，一旦无源组件受焊药的拉引而竖起时，无源组件即无法与焊垫形成完全电性连接的关系而导致制成品电性品质不理想。In addition, passive components are generally electrically connected to the substrate by applying solder paste on the substrate to provide passive component soldering pads (Solder Pad), and the soldering method generally uses remelting Welding (Reflow Soldering) method. During reflow soldering, the change of surface tension caused by the heating of solder tends to cause passive components with gradually miniaturized volume to produce passive float phenomenon. In the space, it is easy to touch the adjacent components or welding wires to cause short circuit; another problem that often occurs in passive components during reflow operation is the tombstone phenomenon. Once the passive components are exposed to solder flux When pulled and erected, the passive component cannot form a complete electrical connection with the pad, resulting in unsatisfactory electrical quality of the finished product.

针对上述无源组件的位移(Shifting)及立碑问题，美国专利5,311,405号案的「用以定位与接置表面黏接组件的方法及装置](Method and Apparatus for Aligning and Attaching a Surface MountComponent)即提出解决方法。该现有技术利用两相对的焊垫使无源组件的两端接置在该两相对的焊垫上，各焊垫是由一椭图形部及一与该椭圆形部连设的角锥部所构成，且该两焊垫的角锥部的尖端乃彼此相向，由于该角锥部的形成，在回熔焊接作业进行时，焊膏涂布于各焊垫的椭圆形部中，在无源组件的两端部接置于该焊药上后，焊药会自椭圆形部流注至角锥部中，此时，焊药的流动即产生一导正该无源组件的拉引力，使无源组件的长轴线得以大致落于通过该两焊垫中心点的中心线，而令无源组件在回焊作业进行时无偏位之虞。For the above-mentioned displacement (Shifting) and tombstone problems of passive components, the "Method and Apparatus for Aligning and Attaching a Surface Mount Component" (Method and Apparatus for Aligning and Attaching a Surface Mount Component) of US Patent No. 5,311,405 is Propose a solution. This prior art utilizes two relative welding pads to make the two ends of the passive component be connected on the two relative welding pads, and each welding pad is formed by an elliptical portion and a joint connected with the elliptical portion. The tips of the pyramids of the two pads face each other. Due to the formation of the pyramids, the solder paste is coated on the ellipse of each pad during the reflow soldering operation. , after the two ends of the passive component are connected to the solder, the solder will flow from the elliptical part into the pyramid part. The pulling force enables the long axis of the passive component to roughly fall on the center line passing through the center points of the two solder pads, so that the passive component has no risk of deviation during the reflow operation.

然而，该第5,311,405号美国专利所提出的无源组件焊接于基板上的方法及结构仍有若干缺点而亟待改良。首先，由于供无源组件焊接的两焊垫位于无源组件的两端部处且须成椭圆形状，使两焊垫占据基板上的面积较现有的单一焊垫者为大，故会影响到基板上导线的布局性(Routability)，且不利于基板的小型化；再者，两焊垫的角锥部的尖端相距甚近，往往易在无源组件黏置于焊药上后，溢流出两角锥部的焊药会触接，使两应分离的焊垫因焊药的溢流而接连，遂导致短路的发生，但为避免焊药溢流而致两焊垫电性相接的问题发生，往往须扩大两焊垫间的距离，如此而为，则将使该两焊垫所占据基板的面积增大，而令布线的困难度提高或甚而须增大基板；同时，无源组件是以两相对焊垫上涂布的焊药焊设于基板上，当两焊垫上的焊药的涂布量不均等时，极可能导致无源组件在回焊作业进行中受到焊药施予不均等的拉引力，而易导致立碑现象的发生；此外，该美国专利所使用的焊垫的形状及构成，无法使用现有的设备及工艺以形成该种焊垫，而须另行设计适用的设备及工艺，且既有的用以涂布焊药的型版(stencile)亦无法适用，因而，此两种相对焊垫的使用会导致制成成本的提高及工艺的复杂化。However, the method and structure for soldering the passive components on the substrate proposed in the US Pat. No. 5,311,405 still have some shortcomings and need to be improved. First of all, since the two welding pads for passive component welding are located at both ends of the passive component and must be in an elliptical shape, the area occupied by the two welding pads on the substrate is larger than that of the existing single welding pad, so it will affect The layout of the wires on the substrate (Routability), and is not conducive to the miniaturization of the substrate; moreover, the tips of the pyramidal parts of the two pads are very close to each other, and it is often easy to overflow after the passive components are attached to the solder. The flux flowing out of the two pyramids will contact, so that the two welding pads that should be separated will be connected due to the overflow of the flux, which will cause a short circuit. If the problem occurs, it is often necessary to expand the distance between the two welding pads. Doing so will increase the area of the substrate occupied by the two welding pads, which will increase the difficulty of wiring or even increase the substrate; at the same time, there will be no The source components are soldered on the substrate with flux coated on two opposite pads. When the amount of flux coated on the two pads is not equal, it is very likely that the passive components will be exposed to flux during the reflow operation. Because of the uneven pulling force, it is easy to cause the tombstoning phenomenon; in addition, the shape and composition of the solder pads used in the US patent cannot use existing equipment and processes to form such solder pads, and must be designed separately Applicable equipment and processes, and the existing stencils for coating flux are also unsuitable. Therefore, the use of these two relative pads will lead to increased manufacturing costs and complicated processes.

发明内容Contents of the invention

本发明的目的在于提供一种避免无源组件焊接时产生偏移或立碑现象的可设置无源组件的基板。The object of the present invention is to provide a substrate on which passive components can be arranged, which avoids offset or tombstoning phenomenon during soldering of passive components.

本发明的另一目的在于提供一种在不致影响导线布局或增大使用面积的状况下，仍能有效避免无源组件焊接时产生偏位或立碑现象的可设置无源组件的基板。Another object of the present invention is to provide a substrate on which passive components can be provided, which can effectively avoid displacement or tombstoning during soldering of passive components without affecting the wiring layout or increasing the use area.

本发明的再一目的在于提供一种可利用已有设备与工艺完成无源组件的焊接且可有效避免无源组件在焊接时产生偏位或立碑现象的可设置无源组件的基板。Another object of the present invention is to provide a substrate on which passive components can be installed, which can complete the soldering of passive components by using existing equipment and technology, and can effectively avoid deviation or tombstoning of passive components during welding.

为达成本发明上述目的，本发明提供的可设置无源组件的基板包括：一芯层，在该芯层上形成一供芯片接置的芯片接置区及一环设于该芯片接置区外以供多个导电迹线布设的导线形成区；一敷布于该导线形成区上的拒焊剂层，以使该导电迹线与外界气密隔离；至少一设于该导线形成区上并外露出该拒焊剂层的焊垫，以供一无源组件藉焊药与的焊接，该焊垫的至少中央部位开设有一中心开槽，以在焊药涂布于该焊垫上时，该中心开槽的形成会使焊药的表面张力朝该中心开槽集中而产生一内聚引力，从而拉引该无源组件定位于焊垫的中心开槽而无偏位或立碑之虞。In order to achieve the above object of the present invention, the substrate provided by the present invention that can be provided with passive components includes: a core layer, on which a chip connection area for chip connection is formed and a ring is arranged on the chip connection area A wire forming area for laying a plurality of conductive traces outside; a solder repellent layer applied on the wire forming area to make the conductive traces airtightly isolated from the outside; at least one wire forming area and outside The welding pad exposing the solder repellent layer is used for soldering of a passive component by means of flux. At least the central part of the welding pad is provided with a central slot, so that when the flux is coated on the welding pad, the central opening The formation of the groove will cause the surface tension of the solder to concentrate toward the central groove to generate a cohesive attractive force, thereby pulling the passive component to be positioned in the central groove of the solder pad without the risk of misalignment or tombstoning.

该焊垫除可开设一中心开槽外，还可以该中心开槽为中心朝焊垫的边缘开设至少一对对称形成的肋状开槽以进一步提高焊药受该开槽形成的影响所产生的内聚引力。该中心开槽的形状无特定限制，圆形或方形均适用，其大小亦无特殊限制，只要不影响无源组件与焊垫的电性导接即可；此外，中心开槽得与肋状开槽的槽径相同，亦可大于肋状开槽的槽径，视实际需要而定。In addition to a central slot, the solder pad can also be provided with at least a pair of symmetrically formed rib-shaped slots towards the edge of the pad to further improve the solder flux produced by the impact of the slot formation. cohesive gravity. The shape of the central slot is not limited, either circular or square, and its size is not particularly limited, as long as it does not affect the electrical connection between passive components and solder pads; The slot diameters of the slots are the same, and may also be larger than the slot diameters of the ribbed slots, depending on actual needs.

本发明的基板上的焊垫得以现有的设备及工艺完成，较现有技术，有成本较低及工艺较简单的优点，且可有效避免无源组件的偏位及立碑现象的发生，还不致影响基板上导电迹线的布设，故可有效解决无源组件与基板的焊接不良存在的诸多问题。The welding pads on the substrate of the present invention can be completed with existing equipment and processes, and compared with the prior art, it has the advantages of lower cost and simpler process, and can effectively avoid the occurrence of passive component deviation and tombstoning. It will not affect the layout of conductive traces on the substrate, so it can effectively solve many problems of poor welding between passive components and the substrate.

附图说明Description of drawings

下面结合附图及实施例对本发明进行详细：The present invention is described in detail below in conjunction with accompanying drawing and embodiment:

图1是本发明第一实施例的基板的主视图；Fig. 1 is the front view of the substrate of the first embodiment of the present invention;

图2是图1沿2-2线的剖视图；Fig. 2 is a sectional view along line 2-2 of Fig. 1;

图3是图2所示的焊垫上敷设焊药后接置一无源组件的剖面示意图；FIG. 3 is a schematic cross-sectional view of a passive component after laying flux on the welding pad shown in FIG. 2;

图4是示图3的焊药在回焊作业进行时所产生的变化的剖面示意图；Fig. 4 is a schematic cross-sectional view showing the changes of the flux of Fig. 3 during the reflow operation;

图5是本发明第二实施例的基板的主视图；Fig. 5 is the front view of the substrate of the second embodiment of the present invention;

图6是本发明第三实施例的基板的主视图；Fig. 6 is the front view of the substrate of the third embodiment of the present invention;

图7是本发明第四实施例的基板的主视图；7 is a front view of a substrate of a fourth embodiment of the present invention;

图8是本发明第五实施例的基板的主视图；及8 is a front view of a substrate of a fifth embodiment of the present invention; and

图9是本发明第六实施例的基板的主视图。Fig. 9 is a front view of a substrate of a sixth embodiment of the present invention.

图中符号说明：Explanation of symbols in the figure:

1                     基板1 Substrate

10                    芯层10 core layer

100                   芯片接置区100 chip placement area

101                   导线形成区101 Conductor forming area

11                    拒焊剂层11 Solder Resist Layer

12，52，62，72，82，92焊垫12, 52, 62, 72, 82, 92 pads

120，520，620，720，820，920开槽120, 520, 620, 720, 820, 920 slotting

S                      焊药S Solder Flux

P                      无源组件P Passive components

具体实施方式Detailed ways

参照图1、2，本发明第一实施例的基板1包括一芯层10，在该芯层10的表面上形成一供芯片接置的芯片接置区100以及一环设于该芯片接置区100外的导线形成区101，该导线形成区101乃供由铜箔经蚀刻处理或印刷(print)方式形成的多个导电迹线(Conductive Traces)布设之用，以藉之使芯片电性连接至该基板1，由于该导电迹线的形成与布设(Routing)为现有技术，故在此未予图标及详细说明。Referring to Fig. 1, 2, the substrate 1 of the first embodiment of the present invention comprises a core layer 10, on the surface of this core layer 10, forms a chip connection area 100 for chip connection and a ring is arranged on this chip connection area. The wire forming area 101 outside the area 100, the wire forming area 101 is used for laying a plurality of conductive traces (Conductive Traces) formed by copper foil through etching or printing (printing), so as to make the chip electrically To be connected to the substrate 1 , since the formation and routing of the conductive traces are prior art, they are not illustrated and described in detail here.

在该芯层10的导线形成区101上敷设有拒焊剂(Solder Mask)层11，以藉之将布设于该导线形成区101上的导电迹线(未图标)与外界气密隔离。在该导线形成区101上并形成有至少一焊垫12，该焊垫12部分外露出该拒焊剂层11，以供无源组件与之电性连接，而使无源组件与基板1形成电性连接关系；该焊垫12以如铜的金属形成，且其形成的方式为现有技术，故在此不另为文赘述。A solder mask layer 11 is laid on the wire forming area 101 of the core layer 10 to airtightly isolate the conductive traces (not shown) disposed on the wire forming area 101 from the outside. At least one pad 12 is formed on the wire formation area 101, and part of the pad 12 exposes the solder repellent layer 11 for electrically connecting the passive component to it, so that the passive component and the substrate 1 form an electrical connection. Sexual connection relationship; the welding pad 12 is formed of metal such as copper, and its forming method is the prior art, so it will not be repeated here.

该焊垫12在外露出拒焊剂层11的部位上并开设有一呈十字交叉的开槽120，使该焊垫12在开槽120形成处产生一凹部，且该呈十字交叉的开槽120的交叉部位位于该焊垫12的中央处，而令该开槽120可视为由在焊垫12的中央处开设的中心开槽及以该中心开槽为中心朝焊垫12及周边延伸开设出的四道对称配置的肋状开槽所构成。The welding pad 12 is provided with a criss-cross slot 120 on the part where the solder repellent layer 11 is exposed, so that the solder pad 12 produces a recess at the place where the slot 120 is formed, and the intersection of the criss-cross slot 120 The position is located at the center of the welding pad 12, so that the groove 120 can be regarded as a central groove opened at the center of the welding pad 12 and a center groove extending toward the welding pad 12 and its periphery with the central groove as the center. It is composed of four symmetrically arranged rib-shaped slots.

再参照图3，开槽120形成后，在焊接无源组件P时，须先在焊垫12上涂布一现有的焊药(Solder Paste)S。焊药S涂布完成后，即进行常用的回熔焊接处理，此时，焊药S受热即产生如图4所示的变化，由于焊垫12具有下凹的开槽120，受焊药S表面张力的作用，位于该开槽120上的焊药S即会向下凹陷而使焊药5产生一向下(Downward)及内聚(Convergent)的拉引力，此一拉引力的产生便形成一将无源组件P定位于焊垫12的开槽120上作用，而使无源组件P在回焊作业中无偏位之虞而不致碰触至邻近的其它组件或焊线，同时，该拉引力可有效地将无源组件P均匀下引而固着于焊药S上，故不会有立碑现象的发生。Referring to FIG. 3 again, after the slot 120 is formed, when soldering the passive component P, an existing solder paste (Solder Paste) S must be coated on the pad 12 first. After the coating of the flux S is completed, the commonly used remelting soldering process is carried out. At this time, the flux S is heated and changes as shown in FIG. Due to the effect of surface tension, the solder S located on the slot 120 will sag downwards, causing the solder 5 to generate a downward and cohesive pulling force, and the generation of this pulling force will form a The passive component P is positioned on the slot 120 of the welding pad 12, so that the passive component P will not be displaced during the reflow operation and will not touch other adjacent components or welding wires. At the same time, the pull The gravitational force can effectively draw down the passive component P evenly and fix it on the solder S, so there will be no tombstoning phenomenon.

因而，清楚可知本发明的基板上的焊垫得以现有的设备及工艺完成，较诸前述的第5,311,405号美国专利，有成本较低及工艺较简单的优点，且可有效避免无源组件的偏位及立碑现象的发生，还不致影响基板上导电迹线的布设，故可有效解决无源组件与基板的焊接不良存在的诸多问题。Therefore, it is clear that the soldering pads on the substrate of the present invention can be completed by existing equipment and processes. Compared with the aforementioned U.S. Patent No. 5,311,405, it has the advantages of lower cost and simpler process, and can effectively avoid passive components. The occurrence of offset and tombstoning will not affect the layout of conductive traces on the substrate, so it can effectively solve many problems of poor soldering between passive components and the substrate.

另，须知本发明所称的基板乃泛指一般在一芯层上形成有多个导电迹线以供半导体装置及/或电子组件接置用的结构，亦即，用于半导体封装件(Semiconductor Package)中的基板或一般所称的印刷电路板(printed Circuit Board)均涵括在内；且构成该基板的层数亦无限制，单层板或多层板均适用。In addition, it should be noted that the substrate referred to in the present invention generally refers to a structure in which a plurality of conductive traces are generally formed on a core layer for semiconductor devices and/or electronic components to be connected, that is, for semiconductor packages (Semiconductor packages). The substrate in the Package) or the commonly called printed circuit board (printed circuit board) are included; and the number of layers constituting the substrate is also unlimited, and both single-layer boards and multi-layer boards are applicable.

图5-9是用以说明本发明第二至六实施例的基板上所形成的焊垫的不同变化。如图5所示，焊垫52的开槽520仅形成于焊垫52的中央处，附图中为矩形，但若为圆形亦适用。如图6所示为焊垫62的开槽62乃一条状的单槽，但仍通过该焊垫62的中心点。如图7所示，该焊垫72的开槽720与前述第一实施例所示大致相同，不同处在于该开槽720乃沿焊垫72的对角线形成，并在焊垫72的中央处交叉。如图8所示，该焊垫82的开槽820为十字形，但其端部并未延伸至与拒焊剂81相接触之处。最后，如图9所示，在焊垫92中央处的开槽920的槽径大于开槽920自中央处向外延伸部位的槽径。5-9 are used to illustrate different variations of pads formed on the substrate according to the second to sixth embodiments of the present invention. As shown in FIG. 5 , the slot 520 of the welding pad 52 is only formed at the center of the welding pad 52 , which is rectangular in the drawing, but it is also applicable if it is circular. As shown in FIG. 6 , the slot 62 of the pad 62 is a single slot in a strip shape, but still passes through the center point of the pad 62 . As shown in FIG. 7 , the groove 720 of the welding pad 72 is substantially the same as that shown in the first embodiment, the difference is that the groove 720 is formed along the diagonal of the welding pad 72 and is in the center of the welding pad 72 cross. As shown in FIG. 8 , the slot 820 of the solder pad 82 is cross-shaped, but its end does not extend to the point where it contacts the solder repellant 81 . Finally, as shown in FIG. 9 , the diameter of the slot 920 at the center of the pad 92 is larger than the diameter of the slot 920 extending outward from the center.

以上所述，仅为本发明的具体实施例而已，其它任何未背离本发明的精神与技术下所作的等效改变或修饰，均应仍包含在本专利的保护范围之内。The above descriptions are only specific examples of the present invention, and any other equivalent changes or modifications made without departing from the spirit and technology of the present invention shall still fall within the scope of protection of this patent.