JPH0917941A - Semiconductor device - Google Patents

Abstract

PURPOSE: To ensure the strength of joints between inner leads and wires without increases in material cost due to increases in the length of wires or increase in manufacturing cost due to increases in processing time in a semiconductor device of such a stricture that a semiconductor pellet and inner leads are connected with each other by wire bonding. CONSTITUTION: Second inner leads 6 are placed between first inner leads 5. The ends of the first inner leads 5 are extended toward an island 2 as far as their width is processable. The second inner leads 6 are extended closer to the island 2 than the ends of the first inner leads 5 are, and the ends of the second inner leads 6 are widened. These inner leads of two types are coupled with each other and secured in the direction of the row using an insulating tape 3 extending from the ends of the first inner leads 5 to the widened ends of the second inner leads 6. The bonding pads on the pellet 1 and the inner leads 5, 6 are connected with each other by a bonding wire 4 bridging the insulating tape 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a semiconductor device having a structure in which an inner lead of a metal lead frame and a bonding pad of a semiconductor pellet are connected by wire bonding.

[0002]

2. Description of the Related Art A top view of an example of a conventional semiconductor device of this kind is shown in FIG. FIG. 3B is a cross-sectional view. This semiconductor device is described in JP-A-64-27236. Referring to FIG. 3, in this semiconductor device, a bonding pad (connection electrode) 8 of semiconductor pellet 1 and a wire bonding portion 10 of inner lead 9 are connected by wire 4 by wire bonding. The insulating tape 3 is attached to the inner lead 9 from the upper surface side (the surface of the lead frame on the pellet mounting side) at the tip of the inner lead 9 and closer to the pellet 1 than the wire bonding portion 10 described above. The inner leads 9 of the inner leads 9 are aligned on the same plane by the tape 3. Thereby, sufficient heat and pressure can be applied between the wire bonding portion 10 of the inner lead 9 and the wire 4 at the time of wire bonding, so that the bonding state between the inner lead 9 and the wire 4 is good. It becomes something.

On the other hand, a semiconductor device whose top view is shown in FIG. 4A and whose cross-sectional view is shown in FIG. 4B is another example of this type of semiconductor device. It is described in Japanese Patent Publication No. Referring to FIG. 4, in this semiconductor device, insulating tape 3 is attached to the lower surface of inner lead 9 so as to include the leading end. The thermosetting adhesive 7 for this attachment is hardened between the inner leads so as to enter between the adjacent leads to connect and fix the inner leads. For this reason, in this semiconductor device, even when subjected to thermal stress, no thermal distortion occurs and the strength is increased. Also, during bonding, the bonding area is kept at the correct position interval without deformation of the inner lead, so that bonding accuracy is improved. In addition, since deformation due to impact during bonding can be prevented, the reliability of the semiconductor device can be improved.

[0004]

In the semiconductor device described in JP-A-64-27236, the tip of the inner lead is fixed from the upper surface with an insulating tape 3, so that the pellet bonding is performed. The wire 4 connecting the pad 8 and the wire joint 10 of the inner lead is inevitably
It will straddle the tape 3. Therefore, in addition to the conventional length, the wire length requires the width of the tape 3 and the distance from the tape end to the wire joint 10. In addition, the time required for wire bonding increases. As a result, the material cost of the wire increases, the manufacturing period is lengthened, and the manufacturing cost increases.

On the other hand, in the semiconductor device described in Japanese Patent Application Laid-Open No. 3-124555, an insulating tape 3 such as a polyimide tape is attached to the back surface of the tip of the inner lead 9.
By the way, at the time of wire bonding, the inner leads 9
Heat and pressure are applied to the wire 4 and the inner lead 9 by applying a bonding tool such as a wedge or a capillary from above the inner lead to the metal heater plate from below. Then
A polyimide tape is interposed between the in-lead 9 and a heater plate (not shown) thereunder. However, not only polyimide tape but also insulating tape generally has poor thermal conductivity and low hardness as compared with metal. Accordingly, in the semiconductor device shown in FIG. 3, the metal heater plate and the inner lead can be brought into direct contact, whereas in the semiconductor device shown in FIG. 4, sufficient heat and pressure can be applied during wire bonding. Can not. As a result, the bonding strength of the wire bonding part is low.

Accordingly, the present invention provides a semiconductor device having a structure in which an inner lead and a pellet are connected to each other by a bonding wire without increasing the manufacturing cost due to an increase in material cost and work period due to the elongation of the wire. The purpose is to secure the bonding strength with the wire.

[0007]

According to the present invention, there is provided a semiconductor device comprising:
An island for mounting a semiconductor pellet, a plurality of inner leads extending horizontally from the outside of the island toward the island, and at least a semiconductor pellet mounted on the island, provided on the semiconductor pellet In a semiconductor device having a structure in which a bonding pad and an inner lead are connected by wire bonding using a thin metal wire, the plurality of inner leads are a first inner lead extending to the vicinity of an island; A second inner lead having a structure in which at least every other inner lead is arranged therebetween, and extends to a position closer to the island than the most distal end position on the island side of the first inner lead and has a widened end portion. And the two types of inner leads are a first inner lead. Insulating tape extending from the tip end on the island side to the widened tip end on the island side of the second inner lead, is connected and fixed in the direction of the line, and connects the bonding pad of the semiconductor pellet to the inner lead. However, it is characterized in that wire bonding is performed over the insulating tape.

[0008]

Next, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged top view showing a main part of a semiconductor device according to one embodiment of the present invention.
Is a side view thereof. Referring to FIGS. 1 and 2, the present embodiment has two types of first inner leads 5 extending in the direction of island 2 and second inner leads extending closer to island 2 than first inner leads 5. It has an inner lead. The insulating tape 3 is adhered to the upper surface of the inner lead (the surface of the lead frame on the pellet mounting side) from the distal end of the first inner lead 5 to the distal end of the second inner lead 6. The position of the tape 3 to be applied is set at 0.2 mm in the direction away from the island 2 from the tip of the second inner lead 6 in consideration of the adhesion accuracy.
It does not protrude from the tip of the second inner lead 6.

The second inner leads 6 are arranged between the first inner leads 5. The tip of the first inner lead 5 is extended to the island 2 side to the minimum lead width that can be processed at the time of manufacturing a lead frame. On the other hand, the tip of the second inner lead 6 is extended further to the island 2 side than the extended front end of the first inner lead 5 to a range where the tape 3 can be stuck. In both the first and second inner leads, simply extending the length of the lead leads to a smaller width at the tip of the lead and a smaller bonding area with the tape 3, so that the bonding strength is reduced. Therefore, the adhesive force with the tape 3 is increased by increasing the width of the distal end of the second inner lead 6 where the distance between the adjacent leads at the distal end is wider and increasing the bonding area.

A first inner lead 5 and a second inner lead 6 to which the insulating tape 3 is attached;
The wire bonding between the semiconductor pellet 1 and the bonding pad mounted thereon is performed such that the wire 4 straddles the tape 3.

In this embodiment, as compared with the conventional semiconductor device shown in FIG. 3, the tip of the inner lead on the island side is extended as much as possible to shorten the wire length. Further, the connection and fixing of the tips of the inner leads in the arrangement direction depend on the insulating tape adhered to the upper surface side of the inner leads. This allows
At the time of bonding the inner lead and the wire, the inner lead and the heater plate are brought into direct contact and
Pressure is applied to ensure the bonding strength between the inner lead and the wire.

From the above description, it is not necessary to arrange the second inner leads 6 one by one for each of the first inner leads, and one second inner lead 6 is arranged for a plurality of first inner leads. Obviously, it is clear that the arrangement does not need to be regular.

[0013]

As described above, in the present invention, the tip of the inner lead on the island side is extended as much as possible to shorten the wire length. In addition, the connection and fixing of the tip of the inner lead in the direction of alignment are performed by using an insulating tape attached to the upper surface of the inner lead, and when the inner lead and the wire are bonded, the inner lead and the heater plate are brought into direct contact. Heating and pressurization are sufficient.

According to the present invention, the deformation of the inner lead and the wire due to the external force applied to the tip of the inner lead can be prevented without increasing the material cost due to the lengthening of the wire and the production cost due to the elongation of the construction period. Moreover, the bonding strength between the inner lead and the wire can be secured.

[Brief description of the drawings]

FIG. 1 is an enlarged top view showing a main part of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is an enlarged side view showing a main part of the semiconductor device according to one embodiment of the present invention.

FIG. 3 is a top view and a cross-sectional view of an example of a conventional semiconductor device using wire bonding.

FIG. 4 is a top view and a cross-sectional view of another example of a conventional semiconductor device using wire bonding.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pellet 2 island 3 insulating tape 4 wire 5 first inner lead 6 second inner lead 7 adhesive 8 bonding pad 9 inner lead 10 wire joint

Claims (1)

[Claims] An island for mounting a semiconductor pellet, a plurality of inner leads extending horizontally from the outside of the island toward the island, and at least a semiconductor pellet mounted on the island; In a semiconductor device having a structure in which a bonding pad provided on a pellet and an inner lead are connected by wire bonding using a thin metal wire, the plurality of inner leads extend to a vicinity of an island; An inner lead arranged at least every other between one inner lead,
The first inner lead includes a second inner lead having a structure in which the first inner lead extends to a position closer to the island than the frontmost position on the island side and has a widened end portion. An insulating tape extending from the island-side tip portion of the first inner lead to the widened tip portion on the island side of the second inner lead;
A semiconductor device, wherein a thin metal wire connected and fixed in the arrangement direction and connecting a bonding pad of the semiconductor pellet and an inner lead is wire-bonded across the insulating tape.