JP3104695B2 - BGA type resin encapsulated semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD [0001] The present invention relates to a BGA (Bal
1 (Grid Array) type resin-sealed semiconductor device.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become higher in performance and smaller, lighter, and thinner, not only high integration of mounted semiconductor devices has been required, but also high speed processing of signals in semiconductor devices has been required. There is also a demand for a reduction in inductance. To meet these requirements, the total number of external terminals is steadily increasing.

In order to cope with this, conventionally, a QFP (Quad Flat) having a structure in which outer leads for electrically connecting to an external circuit in four directions of a semiconductor package are provided.
tPackage) and the like, and a surface mount type package has been used, which has been adapted to increase the number of terminals.

However, in order to respond to the demand for more terminals, the pitch of the outer leads must be further reduced.
Although it is necessary to make the outer leads thinner, problems arise in molding, positioning accuracy, flatness accuracy, and the like of the outer leads.

In order to avoid these problems, a BGA (Ball Grid Array) type semiconductor device which is a surface mount type package using solder balls instead of outer leads has been developed.

FIG. 4 is a schematic sectional view illustrating the structure of a conventional BGA type resin-sealed semiconductor device.

A land 10 is provided on the upper surface of the semiconductor chip 101.
Lead frame 1 other than 3 is half-etched
02 are joined by a tape 107. The semiconductor chip 101 and the lead frame 102 are electrically connected by wires 105, and solder balls 104 as external terminals are provided on the land 103. The parts other than the solder balls 104 are sealed with a resin 106 molded by insert molding or the like.

In the BGA having such a structure, the solder balls 104 are two-dimensionally arranged.
The pitch between the external terminals can be wider than that of the QFP, and the mounting process does not involve difficulty compared to the QFP.

FIG. 5 shows another conventional BGA type resin-sealed semiconductor device.

In the conventional example shown in FIG. 4, half-etching is performed on the portions other than the land portions 103 of the lead frame 102 to prevent the solder balls 103 from melting out of the portions other than the land portions 103. On the other hand, in the conventional example shown in FIG. 5, a flat lead frame 206 is used, and a portion corresponding to the land portion 203 is sealed with a resin 206 having a concave portion 208 formed thereon, thereby forming the land portion 2 of the solder ball 204.
Prevents melting to other than 03.

[0011]

However, in the conventional example shown in FIG.
Becomes vulnerable by half-etching other than 03,
It is disadvantageous in strength.

As shown in FIG. 5, in order to form the concave portion 208 in the resin 206, a convex portion should be formed in a portion corresponding to the concave portion 208 of the mold used for sealing with the resin 206. Must-have. However, there is a limit in the production of the mold also in the formation of the protrusions, and it is difficult to form the protrusions at a pitch of 0.65 mm or less.

In order to solve the above problem, the lead frame is not half-etched, and the mold for sealing the resin does not have a convex portion for forming a concave portion in the resin. Assume that a flat mold is used. FIG. 6 shows a top view of the semiconductor device thus formed. The land portion 303 and the lead frame 302 are both exposed on the surface of the semiconductor device 300, and are not insulated by the resin 306.

FIG. 7 is a diagram showing a state in which solder balls are placed on the semiconductor device 300 shown in FIG. 6 as viewed from the direction of arrow A shown in FIG.

When the solder ball 304 is mounted on the land portion 303 in such a state, the solder ball 304 flows from the land portion 303 toward the lead frame 302 to the outflow portion 3.
04a and it will flow out.

Accordingly, it is a first object of the present invention to provide a BGA-type resin-sealed semiconductor device having secured mechanical strength. BGA with a narrow pitch between terminals
A second object is to provide a mold resin-sealed semiconductor device.

[0017]

In order to achieve the above object, a BGA type resin-sealed semiconductor device according to the present invention is provided on a semiconductor chip, and is provided on an upper surface of the semiconductor chip, and is electrically connected to the semiconductor chip. And a lead frame having a plurality of lands arranged in parallel and having a groove formed in the periphery, a solder ball placed on the land, sealing the semiconductor chip, and filling the groove. And a resin having a property that the solder ball does not stick.

In the BGA-type resin-sealed semiconductor device of the present invention configured as described above, since the groove is formed only around the land portion of the lead frame on which the solder ball is placed, the lead frame can be made thinner. Can be minimized.
In addition, since insulation between the land and the lead frame other than the land is performed by filling the groove with a resin, the insulation is performed by exposing only the land and sealing the lead frame other than the land. There is no need for a mold for molding the shaped resin.

The lead frame other than the land portion may be sealed with a resin, and the arrangement pitch of the land portions may be 0.65 mm or less. Further, the groove may be formed within a range of 0.4 mm or less from the outer periphery of the land portion, or the groove may be formed by a half-etching process. The surface of the resin and the surface of the resin are preferably flat.

[0020]

Next, embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 is a schematic sectional view of a BGA type resin-sealed semiconductor device of this embodiment, and FIG. 2 is a top view of the semiconductor device shown in FIG.

A tape 7 is attached to both sides of the upper surface of the semiconductor chip 1, and a lead frame 2 made of a conductive member is attached thereon. The semiconductor chip 1 and the lead frame 2 are electrically connected by wires 5. Further, around the land 3 on which the solder balls 4 are mounted, a half-etched land peripheral half-etched portion 8 is formed. Half etch part 8 around land
In addition, a resin 6 which is formed around the semiconductor chip 1 by insert molding or the like and has a property that the solder ball 4 does not stick is formed.
It is sealed with. The lead frame 2 and the land portion 3 which are not sealed with the resin 6 are exposed on the upper surface of the BGA type resin-sealed semiconductor device. The part 3 is configured to be separated by the resin 6. The surface of the land 3 and the surface of the resin 6 are flat. The solder ball 4 is placed on the land 3 after the semiconductor chip 1 is sealed with the resin 106.

The BG according to the present embodiment having the above configuration
The A-type resin-encapsulated semiconductor device has a structure in which the land portion 3 and the lead frame 2 are formed on the surface of the semiconductor device without performing a half-etching process on all of the lead frame 102 except for the land portion 103 as in the related art shown in FIG. Can be separated from each other. For this reason, the reduction in strength of the lead frame 2 can be minimized, and the BGA
The reduction in the strength of the mold resin-sealed semiconductor device is also minimized.

Further, unlike the conventional example shown in FIG. 5, it is not necessary to form a convex portion in a mold for enclosing the resin 208 for forming the concave portion 208 in the resin 206. Therefore, the pitch between the terminals is not affected by the processing limit of the mold.
The terminal pitch can be 65 mm or less. When the pitch between terminals is 0.65 mm or less, it is preferable that the half-etched portion 8 around the land is formed within 0.4 mm around the land 3. Further, since the cavity surface of the mold corresponding to the land portion 3 has a flat shape, even if the pitch between terminals of the BGA type resin-sealed semiconductor device or the diameter of the solder ball 4 is changed, the mold is removed. There is no need to make it again.

Furthermore, since the lead frame 2 and the land 3 are separated by the resin 6 on the upper surface of the BGA type resin-sealed semiconductor device, the solder balls 4 flow out of the land 3 to the lead frame 2. Nothing to do.

As described above, according to the BGA-type resin-sealed semiconductor device of the present embodiment, without impairing the mechanical strength,
The pitch between terminals can be reduced. (Second Embodiment) FIG. 3 is a schematic sectional view of a part of a BGA type resin-sealed semiconductor device according to a second embodiment.

The bottom surface of the concave portion 28 formed in the resin 16 for sealing the lead frame 12 has a large land corresponding to the large solder ball 204 originally used in the conventional BGA type resin sealed semiconductor device shown in FIG. The small land portion 1 has a smaller diameter than the large land portion 13b.
3a, and the periphery thereof is a land peripheral half-etched portion 18.

As described above, in the present embodiment, the conventional BGA in which the concave portion is formed, which has the mechanical strength shown in FIG.
The size of the solder ball 14 can be reduced without changing the mold for resin sealing used for manufacturing the mold resin-sealed semiconductor device.

[0028]

As described above, according to the present invention, since the groove is formed only around the land portion of the lead frame on which the solder ball is placed, the thickness of the lead frame can be minimized. . For this reason, it is possible to suppress a decrease in the mechanical strength of the BGA-type resin-sealed semiconductor device due to the insulation treatment between the lead frame and the land.

Since the land and the lead frame other than the land are insulated by filling the groove with resin, the insulation is achieved by exposing only the land and sealing the lead frame other than the land. There is no need for a mold for molding a resin having the shape to be performed. For this reason, the land portion, that is, the arrangement pitch between the terminals is not affected by the processing limit of the mold, so that the pitch between the terminals can be narrowed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a BGA type resin-sealed semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a top view of the BGA type resin-sealed semiconductor device shown in FIG.

FIG. 3 is a schematic sectional view of a part of a BGA type resin-sealed semiconductor device according to a second embodiment of the present invention.

FIG. 4 is a schematic sectional view illustrating the structure of a conventional BGA-type resin-sealed semiconductor device.

FIG. 5 is a schematic sectional view illustrating the structure of another conventional BGA-type resin-sealed semiconductor device.

FIG. 6 is a top view of a BGA-type resin-sealed semiconductor device having a lead frame that has not been subjected to a half-etching process and is manufactured by using a mold having no convex portion for forming a concave portion in a resin.

FIG. 7 is a view of the BGA type resin-sealed semiconductor device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor chip 2, 12 Lead frame 3 Land part 3a Small land part 3b Large land part 4, 14 Solder ball 5 Wire 6, 16 Resin 7 Tape 8, 18 Land periphery half-etch part 28 Depression

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 23/50 H01L 23/12

Claims (6)

(57) [Claims] 1. A semiconductor chip, comprising: a plurality of lands provided on an upper surface of the semiconductor chip and electrically connected to the semiconductor chip, arranged in parallel and formed with a groove around the land. A BGA-type resin-sealed semiconductor, comprising: a lead frame; a solder ball placed on the land portion; and a resin that seals the semiconductor chip and fills the groove, and has a property that the solder ball does not ride. apparatus. 2. The BG according to claim 1, wherein the lead frame other than the land portion is sealed with the resin.
A-type resin-sealed semiconductor device. 3. The arrangement pitch of the land portions is 0.65 m.
The BGA type resin-sealed semiconductor device according to claim 1, wherein m is equal to or less than m. 4. The groove is 0.4 mm from the outer periphery of the land.
The BGA type resin-sealed semiconductor device according to claim 1, wherein the BGA type resin-sealed semiconductor device is formed within a range of not more than mm. 5. The BGA type resin-sealed semiconductor device according to claim 1, wherein said groove is formed by a half-etching process. 6. The BGA type resin-sealed semiconductor device according to claim 1, wherein a surface of said land portion and a surface of said resin are flat.