JP2006196667A - Manufacturing method of semiconductor package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of semiconductor package for realizing rigid deposition thereof on a mounting substrate by projecting terminal electrodes formed by etching from the lower surface of the same package. <P>SOLUTION: In the manufacturing method of semiconductor package provided with a plurality of independent terminal electrodes, terminal electrodes are formed by etching on a supporting tape (1) and the supporting tape (1) is peeled after the terminal electrodes are fixed under the condition that an external substrate connecting surface side of the terminal electrodes is embedded by 50 to 60 μm to a supporting tape (2). Subsequently, a semiconductor element is mounted to the terminal electrodes, the semiconductor element and the terminal electrodes are connected with bonding wires, and thereafter the supporting tape (2) is peeled arter the semiconductor element and terminal electrodes are sealed with resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a semiconductor package. More specifically, the present invention relates to a method for manufacturing a semiconductor package in which a terminal electrode is protruded from the lower surface of the semiconductor package to thereby achieve firm fixation to a mounting substrate.

  2. Description of the Related Art Conventionally, a semiconductor package uses a lead frame 103 as shown in FIG. 6 in which a desired pattern is formed by stamping or etching a metal plate with a precision press and having a die pad 101 and a plurality of leads 102 for fixing a semiconductor element. After fixing the semiconductor element on the die pad of the lead frame and wire bonding the semiconductor element and the tip of the lead (terminal electrode), the inside of the lead including the semiconductor element and the bonding wire is sealed with an insulating resin. It is manufactured by cutting and removing unnecessary lead frame portions and cutting leads protruding from the package (see, for example, Patent Document 1).

  Here, in recent years, it has been required to increase the number of terminal electrodes. As shown in FIG. 7, an auxiliary lead 104 is formed between the leads, and the tip 105 of the auxiliary lead functions as a terminal electrode. As a result, a multi-row terminal electrode has been realized.

However, in such a method of increasing the number of terminal electrodes, it is necessary to widen the distance between the leads in order to form auxiliary leads between the leads, and it is difficult to meet the demand for miniaturization of the semiconductor package. there were. In the method of forming auxiliary leads to increase the number of terminal electrodes, two lines are the limit due to technical problems.
Furthermore, it is very difficult to form the auxiliary leads, and there is a disadvantage that the assembly cost increases.

In view of these points, a semiconductor package manufacturing method is proposed in which a semiconductor element is disposed on a plurality of mutually independent terminal electrodes, and the semiconductor element and the terminal electrode are bonded and connected after resin bonding (for example, (See Patent Document 2).
Hereinafter, a conventional method for manufacturing a semiconductor package will be described with reference to the drawings.

  In the conventional semiconductor package manufacturing method, first, as shown in FIG. 8A, a copper thin film is formed on the surface of a heat-resistant support tape 106, and then copper is used using a general-purpose photolithography technique and etching technique. The thin film is etched to form a large number of terminal electrodes 107 regularly arranged at predetermined intervals.

  Next, as shown in FIG. 8 (b), the semiconductor element 108 is mounted, and a wire bonding operation for electrically connecting the semiconductor element and the terminal electrode by a bonding wire 109 made of a thin gold wire is performed. The semiconductor element, the bonding wire, and the terminal electrode are sealed with the molding resin 110 using the transfer molding technique.

  Next, as shown in FIG. 8C, after the support tape is peeled off, the dicing tape 111 is bonded and separated by the dicing blade 112 to obtain a semiconductor package.

JP 2002-280493 A JP 2004-266195 A

However, the semiconductor package obtained by the conventional method of manufacturing a semiconductor package has insufficient mounting strength on the mounting substrate because the lower surface of the semiconductor package and the connection surface of the terminal electrode to the mounting substrate are in the same plane. Improvement in mounting strength has been demanded.
That is, as shown in FIG. 9A, when the semiconductor package is mounted on the mounting substrate 113, the bonding material 114 such as solder paste is adhered only to the lower surface of the terminal electrode, and the outside of the mounting substrate. Since the bonding with the terminal 115 is insufficient, the bonding strength is insufficient, and an improvement in the bonding strength between the terminal electrode and the external terminal of the mounting substrate has been demanded.

  Further, in the conventional method for manufacturing a semiconductor package, since the adhesive tape and the support tape are bonded only on the lower surface of the terminal electrode, the adhesive force is poor, and the terminal electrode may be lost before or during the assembly of the semiconductor package.

  Further, in order to suppress the missing of the terminal electrode and facilitate the wire bonding operation, the external substrate connection surface connected to the external substrate indicated by the symbol a in FIG. When the bonding wire connecting surface that is connected to the semiconductor element is formed by the bonding wire indicated by the middle symbol b, the stability of the terminal electrode is poor, and the terminal electrode is tilted by the weight of the bonding tool during wire bonding work. May also affect sex.

Patent Document 2 also discloses a method of mounting a terminal electrode made of copper on the surface of a support tape by mounting. The semiconductor element is mounted in a state in which a part of the terminal electrode is embedded in the support tape by mounting. In the semiconductor package manufacturing method in which the resin sealing is performed after mounting and wire bonding work, the above-described problems do not occur.
However, considering that the miniaturization of the terminal electrode is progressing and that a highly accurate arrangement of the terminal electrode is required, it is extremely difficult to arrange the terminal electrode by mounting on the surface of the support tape.

  The present invention was devised in view of the above points, and is a semiconductor package that can realize firm fixation to a mounting substrate by projecting a terminal electrode formed by etching from the lower surface of the semiconductor package. The object is to provide a manufacturing method.

  In order to achieve the above object, in a method for manufacturing a semiconductor package according to the present invention, in a method for manufacturing a semiconductor package comprising a terminal electrode having a plurality of mutually independent bonding wire connection surfaces and an external substrate connection surface, A step of forming the terminal electrode on the support by etching so that the bonding wire connection surface is on the first support side; and a terminal electrode formed on the first support; A step of fixing the external substrate connecting surface side with a predetermined depth embedded by a support, a step of removing the first support, a step of mounting a semiconductor element on the terminal electrode, and the semiconductor A step of removing the second support after sealing the element and the terminal electrode with resin is provided.

  Here, the terminal electrode formed on the first support is fixed in a state where the external substrate connection surface side is embedded to a predetermined depth by the second support, and a semiconductor element is mounted on the terminal electrode. After the semiconductor element and the terminal electrode are sealed with resin, the second support is removed to obtain a semiconductor package in which the external substrate connection surface of the terminal electrode protrudes from the lower surface (sealing resin) of the semiconductor package. .

  Further, in the method of manufacturing a semiconductor package according to the present invention, in the method of manufacturing a semiconductor package comprising a terminal electrode having a plurality of mutually independent bonding wire connection surfaces and an external substrate connection surface, The step of forming the terminal electrode by etching so that the bonding wire connection surface is on the first support side, and the terminal electrode formed on the first support is connected to the external substrate by the second support. Fixing the surface side in a state where the surface side is embedded at a predetermined depth; removing the first support; and at least part of the gap between the terminal electrodes fixed by the second support. A step of embedding with a material, a step of mounting a semiconductor element on the terminal electrode, and a step of resin-sealing the semiconductor element and the terminal electrode.

  Here, the terminal electrode formed on the first support is fixed in a state where the external substrate connection surface side is embedded to a predetermined depth by the second support, and further fixed by the second support. After embedding at least a part of the gap between the terminal electrodes with a non-conductive material, a semiconductor element is mounted on the terminal electrode, and the semiconductor element and the terminal electrode are sealed with a resin so that the external substrate connection surface of the terminal electrode is a semiconductor. A semiconductor package protruding from the lower surface (non-conductive material) of the package can be obtained.

  In the semiconductor package manufacturing method to which the present invention is applied, a semiconductor package in which the external substrate connection surface of the terminal electrode protrudes from the lower surface of the semiconductor package can be obtained, and is applied not only to the lower surface of the terminal electrode but also to the side surface of the terminal electrode. Since the bonding material can be adhered, the bonding strength between the terminal electrode and the external terminal of the mounting substrate is improved.

  In addition, since the terminal electrode is fixed in a state where the external substrate connection surface is embedded to a predetermined depth by the second support, the terminal electrode in the semiconductor package manufacturing process such as mounting of a semiconductor element or wire bonding work is performed. Can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings to facilitate understanding of the present invention.

1 and 2 are schematic cross-sectional views for explaining an example of a semiconductor package manufacturing method to which the present invention is applied.
In an example of a method for manufacturing a semiconductor package to which the present invention is applied, first, as shown in FIG. 1 (a), the surface of a support tape (1) 1 made of adhesive polyimide or the like that can withstand a wet etching process described later is applied. After bonding the lead frame material 3 made of copper having a thickness of about 0.2 mm with the Ag plating layer 2 formed on one side, the lead frame material is etched using general-purpose photolithography technology and etching technology. As shown by 1 (b), a large number of terminal electrodes 4 regularly arranged at predetermined intervals are formed.

  Here, the Ag plating layer formed on the surface of the lead frame material is used to improve the connectivity between the bonding wire and the terminal electrode, so long as the connectivity between the bonding wire and the terminal electrode is improved. The plating layer may be formed of another material such as Au, or the plating layer may not be formed if sufficient connectivity is obtained.

Further, the lead frame material to be bonded to the surface of the support tape (1) may be any material as long as it has conductivity, and need not be a copper lead frame material.
The support tape (1) has a function of protecting the Ag plating layer from an etching solution during the etching process and a function of holding a terminal electrode formed by etching.

The terminal electrode may have any shape as long as the semiconductor element and the external substrate can be electrically connected by performing wire bonding, which will be described later. Even if the terminal electrode is fixed in 2), it is conceivable that the terminal electrode is missing after the support tape (1) is peeled off. As shown in (b), it is preferable to form the bonding wire connection surface to be larger than the external substrate connection surface.
In addition, facilitation of the wire bonding operation mentioned later can also be aimed at by forming a bonding wire connection surface large.

  Next, as shown in FIG. 1 (c), the support tape (2) 5 is subjected to heat treatment or the like in a state where the external substrate connection surface side of the terminal electrode is embedded in about 50 to 60 μm. (2) is cured to fix the terminal electrode. Thereafter, the support tape (1) is peeled off as shown in FIG.

  Here, in the present embodiment, the support tape (2) is used to fix the terminal electrode in an embedded state on the external substrate connection surface side, but it is not always necessary to fix the terminal electrode using the support tape, For example, the terminal electrode may be fixed by applying a liquid resin or a resist used for protecting the surface of the substrate to the external substrate connection surface side of the terminal electrode and then curing it by heat treatment or the like. Note that the depth at which the terminal electrode is embedded can be arbitrarily adjusted in consideration of the height at which the standoff is desired.

  In addition, since the temperature of the wire bonding operation and the resin sealing operation by transfer molding technology, which will be described later, may increase to about 300 ° C., the support tape (2) is made of resin by the wire bonding operation or transfer molding technology. A material having heat resistance enough to withstand the temperature of the sealing work is used.

  Next, as shown in FIG. 2A, a semiconductor element 7 is mounted on a terminal electrode using a die bond material 6 such as a die bond paste or a die bond film, and a chip electrode 8 formed on the surface of the semiconductor element; The terminal electrode is electrically connected by a bonding wire 9 made of a fine metal wire such as Au.

  Subsequently, using a general-purpose transfer mold technique, as shown in FIG. 2B, the semiconductor element, the bonding wire, and the terminal electrode are sealed with the sealing resin 10 to obtain the combined body 11 of the semiconductor package. Can do.

  The sealing with the sealing resin is sufficient if the semiconductor element, the bonding wire, and the terminal electrode can be sealed. It is not always necessary to perform the resin sealing using the transfer molding technique. For example, the potting molding technique However, it is considered that the resin sealing by the transfer molding technique is preferable in consideration of productivity.

  Next, after the support tape (2) is peeled off by chemical methods such as chemical etching or mechanical removal using water pressure, the combined semiconductor package is bonded to the dicing tape 12, and FIG. As shown in FIG. 2C, the semiconductor package as shown in FIG. 2D can be obtained by dividing the combined body of the semiconductor packages into pieces by the dicing blade 13.

  In one example of a semiconductor package manufacturing method to which the present invention is applied, a semiconductor package manufacturing method in which a semiconductor element of the same size is mounted on a substrate and a single semiconductor element is mounted in the semiconductor package is provided. Although described by way of example, the present invention is not limited to such a manufacturing method. For example, as shown in FIG. 4A, a semiconductor package including semiconductor elements of different sizes is manufactured in the same process. Alternatively, as shown in FIG. 4 (b), two semiconductor elements mounted on the terminal electrode may be included in the same semiconductor package, and as shown in FIG. 4 (c). A semiconductor package in which a semiconductor element is further mounted on the semiconductor element mounted on the terminal electrode via an insulating film may be used. In addition, the dotted line shown with the code | symbol c in FIG. 4 represents the location cut | disconnected by a dicing blade when dividing into pieces.

In an example of a semiconductor package manufacturing method to which the present invention is applied, a semiconductor package in which the external substrate connection surface of the terminal electrode protrudes from the sealing resin that is the lower surface of the semiconductor package can be obtained, as shown in FIG. In addition, since the bonding material 15 can be adhered not only to the lower surface of the terminal electrode but also to the side surface of the terminal electrode, the mounting strength on the mounting substrate 16 can be improved.
That is, when a semiconductor package obtained by a semiconductor package manufacturing method to which the present invention is applied is mounted on a mounting substrate using solder or the like, the connectivity between the terminal electrode and the solder or the like is improved by the anchor effect, and the semiconductor package Improvement in connection reliability can be expected.

  In addition, since the external substrate connection surface of the terminal electrode protrudes from the lower surface of the semiconductor package, the standoff, which is the distance between the lower surface of the semiconductor package and the external substrate connection surface of the terminal electrode, can be increased, and the semiconductor package is mounted. When the semiconductor package is mounted on the substrate, the floating of the semiconductor package due to the foreign matter adhering to the mounting substrate can be reduced, and the tempering failure of the terminal electrode can be suppressed.

  Furthermore, since the terminal electrode is fixed in a state of being embedded in the support tape (2), it is possible to suppress the loss of the terminal electrode in the manufacturing process of the semiconductor package such as mounting of the semiconductor element or wire bonding work.

  In addition, since wire bonding is performed with the terminal electrode embedded and fixed in the support tape (2), ultrasonic vibration at the time of wire bonding is reliably transmitted, and the reliability of wire bonding is improved. Can be planned.

FIG. 5 is a schematic cross-sectional view for explaining another example of a semiconductor package manufacturing method to which the present invention is applied.
In another example of the method for manufacturing a semiconductor package to which the present invention is applied, a terminal electrode is formed on the surface of the support tape (1) as in the example of the method for manufacturing a semiconductor package to which the present invention is applied. In the state where the external substrate connection surface side of the terminal electrode is embedded in 50 to 60 μm in (2), the support tape (2) is cured to fix the terminal electrode, and then the support tape (1) is peeled off (FIG. 5A )reference.).

  Next, as shown in FIG. 5B, the resin material 14 is filled in the gaps between the terminal electrodes using a general-purpose transfer molding technique.

  Here, it is sufficient that the terminal electrode is fixed by the resin material, and it is not always necessary to fill the gap between the terminal electrodes with the resin material. The terminal electrode is embedded by embedding the resin material in a part of the gap between the terminal electrodes. It may be fixed. However, in order to fix the terminal electrode more reliably, it is preferable to fill the gap between the terminal electrodes with a resin material.

  In this embodiment, the resin material is filled in the gap between the terminal electrodes by the transfer molding technique. However, any method such as a printing method can be used as long as the resin material can be filled in the gap between the terminal electrodes. I do not care.

  In this embodiment, a resin material is used as the nonconductive material filling the gap between the terminal electrodes. However, any nonconductive material can be used as long as the terminal electrodes can be fixed in an insulated state. Of course, it is not limited to the resin material.

  The support tape (2) may be peeled off at this point, but in this embodiment, in order to prevent scratches on the terminal surface in the subsequent steps, the peeling is not carried out at this point and dicing described later. It is assumed that peeling is performed immediately before the process.

  Next, similarly to the example of the semiconductor package manufacturing method to which the present invention is applied, the semiconductor element is mounted, the semiconductor element and the terminal electrode are electrically connected by a bonding wire, and then sealed with a sealing resin. Then, a combined body of the semiconductor package can be obtained, and then the support tape (2) is peeled off and the combined body of the semiconductor package is separated into pieces as shown in FIG. A semiconductor package can be obtained.

  It should be noted that a semiconductor package including semiconductor elements having different sizes may be manufactured by the same process, or may be a semiconductor package including two or more semiconductor elements. This is the same as the manufacturing method.

  In another example of the semiconductor package to which the present invention is applied, a semiconductor package can be obtained in which the external substrate connection surface of the terminal electrode protrudes from the resin material that is the lower surface of the semiconductor package. Since the bonding material can be adhered also to the side surfaces, the mounting strength on the mounting substrate can be improved. In addition, the standoff can be increased, and the tempering failure of the terminal electrode can be suppressed.

  In addition, since the terminal electrode is fixed in the state of being embedded in the support tape (2) and the gap between the terminal electrodes is filled with a resin material, the semiconductor package is manufactured such as mounting of a semiconductor element or wire bonding work. Missing terminal electrodes in the process can be suppressed.

  Further, since the terminal electrode is embedded and fixed in the support tape (2) and the wire bond connection is performed in a state where the gap between the terminal electrodes is filled with the resin material, the ultrasonic vibration at the time of the wire bond connection, etc. It is transmitted reliably and the reliability of wire bond connection can be improved.

It is typical sectional drawing (1) for demonstrating an example of the manufacturing method of the semiconductor package to which this invention is applied. It is typical sectional drawing (2) for demonstrating an example of the manufacturing method of the semiconductor package to which this invention is applied. It is typical sectional drawing for demonstrating the shape of a terminal electrode. It is a typical top view for explaining the modification of the semiconductor package to which the present invention is applied. It is typical sectional drawing for demonstrating another example of the manufacturing method of the semiconductor package to which this invention is applied. It is a figure (1) for demonstrating the conventional lead frame. It is FIG. (2) for demonstrating the conventional lead frame. It is typical sectional drawing for demonstrating the manufacturing method of the conventional semiconductor package. It is typical sectional drawing which shows the mounting state of the semiconductor package to a mounting board | substrate.

Explanation of symbols

1 Support tape (1)
2 Ag plating layer 3 Lead frame material 4 Terminal electrode 5 Support tape (2)
6 Die Bond Material 7 Semiconductor Element 8 Chip Electrode 9 Bonding Wire 10 Sealing Resin 11 Semiconductor Package Combined Body 12 Dicing Tape 13 Dicing Blade 14 Resin Material 15 Bonding Material 16 Mounting Board

Claims (6)

In a method for manufacturing a semiconductor package comprising a terminal electrode having a plurality of mutually independent bonding wire connection surfaces and an external substrate connection surface,
Forming the terminal electrode on the first support by etching so that the bonding wire connection surface is on the first support; and
Fixing the terminal electrode formed on the first support in a state where the external substrate connection surface side is embedded to a predetermined depth by the second support;
Removing the first support;
Mounting a semiconductor element on the terminal electrode;
A method of manufacturing a semiconductor package, comprising: removing the second support after sealing the semiconductor element and the terminal electrode with resin. The method of manufacturing a semiconductor package according to claim 1, wherein the terminal electrodes are aligned at a predetermined interval. In a method for manufacturing a semiconductor package comprising a terminal electrode having a plurality of mutually independent bonding wire connection surfaces and an external substrate connection surface,
Forming the terminal electrode on the first support by etching so that the bonding wire connection surface is on the first support; and
Fixing the terminal electrode formed on the first support in a state where the external substrate connection surface side is embedded to a predetermined depth by the second support;
Removing the first support;
Filling at least part of the gap between the terminal electrodes fixed by the second support with a non-conductive material;
Mounting a semiconductor element on the terminal electrode;
A method of manufacturing a semiconductor package, comprising: resin sealing the semiconductor element and the terminal electrode. The method of manufacturing a semiconductor package according to claim 3, wherein the second support is removed after the resin sealing. The semiconductor package manufacturing method according to claim 3, wherein a gap between the terminal electrodes is filled with the non-conductive material. The method of manufacturing a semiconductor package according to claim 3, wherein the terminal electrodes are aligned at a predetermined interval.

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