JP2919415B2 - Lead frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lead frame, and more particularly to a lead frame for a resin-sealed semiconductor device.

[0002]

2. Description of the Related Art A conventional lead frame is shown in FIG.
As shown in FIG. 2B, a plane including the internal leads 3 is different from the plane including the internal leads 3 by a frame-shaped insulating tape 5 bonded to the internal leads 3 to connect and fix the internal leads 3 to each other and a step 4 provided on the suspension leads 2. And an island 1 supported in a plane.

[0003]

The first problem is that, in a conventional resin-encapsulated semiconductor device using a lead frame, a bonding wire of an internal lead adjacent to a suspension lead is cut when a user mounts a substrate. Would. The reason is that the separation between the lead resins due to water expansion from the island progresses to the insulating tape, and then reaches the adjacent internal leads along the tape. At that time, the neck of the bonding ball is disconnected.

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable resin-encapsulated mold that prevents broken lines of a bonding ball from being caused on a bonding surface of an adjacent internal lead without causing the progress of peeling of a suspension lead occurring when a user mounts a substrate. It is to provide a semiconductor device.

[0005]

According to the present invention, there is provided a lead frame, wherein the internal lead and the suspension lead are adhered to the internal lead.
A frame-shaped insulating tape connecting the upper surfaces of the suspension leads to each other and an island provided in a plane different from the plane including the internal lead by providing a step section on the suspension lead; the provided heart portion in said insulating tape, outward from the center portion of the insulating tape
Is the upper part of the step of the suspension lead.
The center of the insulating tape.
The part inside from the upper part of the step of the suspension lead
Projecting horizontally as it is and connected with the frame-shaped insulating tape.
The insulating tape is placed on the upper surface of the tied internal leads.
It is adhered on the whole surface including the inside and outside . Alternatively, cut the insulating tape of the portion connecting the suspension lead and the internal lead, cut off the suspension lead and the internal lead ,
The insulating tape partially adheres to the upper surface of the suspension lead
Have been .

In a resin-encapsulated semiconductor device, when mounted on a substrate, the swelling moisture from the mounting material applied on the island is:
Proceed from the island along the suspension leads and the insulating tape. As a result, the peeling of the insulating tape and the resin reaches the bonding area of the adjacent internal lead along the upper surface of the insulating tape.

According to the present invention, since the step portion of the suspension lead is located at the center of the lower surface of the insulating tape, the peeling that occurs along the suspension lead from the island proceeds only on the lower surface of the insulating tape. No peeling occurs on the upper surface. Alternatively, a path of separation from the insulating tape to the adjacent internal lead is cut off by separating the insulating tape between the suspension leads.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIGS. 1 (a) and 1 (b) are a plan view of a lead frame and an AO-A according to a first embodiment of the present invention.
It is A 'line sectional drawing. The lead frame according to the first embodiment of the present invention is, as shown in FIGS. 1A and 1B, a frame-shaped insulating tape which adheres to the internal leads 3 to connect and fix the internal leads 3 to each other. 5 and an island 1 provided with a stepped portion 4 on the suspension lead 2 outside the insulating tape 5 and supported in a plane different from the plane including the internal lead 3. An insulating tape 5 is stuck at the center. Since the lower surface of the insulating tape 5 is in contact with the step portion 4 of the suspension lead 2, the resin-encapsulated semiconductor device using the lead frame according to the first embodiment can be mounted on the island 1 generated when the user mounts the substrate. Peeling from the resin along the suspension leads 2 occurs only on the lower surface of the insulating tape 5 and does not occur on the upper surface. As a method of obtaining the same effect, a method of removing the insulating tape 5 on the suspension lead 2 is considered.
Since the peeling generated on the suspension leads 2 reaches the outside of the package, a moisture path from the outside of the package is formed, and the moisture resistance is reduced. In other words, by attaching the insulating tape 5 to the suspension leads 2, the effect of preventing the occurrence of a moisture path between the island 1 and the outside of the package is maintained.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 1A and 1B are a plan view and a sectional view taken along line AOA 'of a lead frame showing an embodiment of the present invention. The island 1, the suspension leads 2, and the internal leads 3 of the present lead frame are made of 42 alloy or copper having a thickness of about 150 μm. The suspension lead 2 has a height of about 200 μm.
A step of about 400 μm is provided. This is Island 1
Is supported on a plane different from the internal lead 3. An insulating tape 5 having a width of about 2 nm is bonded to connect the internal leads 3. Here, the insulating tape 5 has a thickness of about 100
The adhesive was applied to a thickness of about 20 μm on a μm polyimide. The embodiment is constituted by bonding the insulating tape 5 so that the step 4 becomes the center of the width of the insulating tape when the insulating tape 5 is attached. In the present embodiment, only the shape of the insulating tape 5 was changed and no special processing was required, so that the cost was not increased.

Next, a second embodiment of the present invention will be described with reference to the drawings.

FIGS. 2A and 2B are a plan view and a cross-sectional view taken along the line BB 'of a lead frame showing a second embodiment of the present invention. As shown in FIGS. 2A and 2B, the lead frame according to the second embodiment of the present invention is the same as that shown in FIGS.
The insulating tape 5 has a shape in which only the connecting portion between the internal lead 3 and the suspension lead 2 is removed from the conventional lead frame shown in FIG. In the present embodiment, since the internal lead 3 and the suspension lead 2 are completely separated from each other, the peeling of the insulating tape 5 from the suspension lead 2 does not proceed to the adjacent internal lead 3. The present embodiment is superior to the first embodiment in preventing peeling along the insulating tape 5, but in the manufacture of the lead frame of the present embodiment, the insulating tape is attached after the insulating tape is attached. An additional cutting step is required, resulting in high costs. Therefore, the first embodiment is the best when viewed comprehensively.

[0014]

The first effect is that the resin-encapsulated semiconductor device using the present invention does not cause breakage of the bonding wire of the internal lead adjacent to the suspension lead when the user mounts the substrate. The reason for this is to prevent separation of the resin from proceeding from the suspension lead, which causes the breakage of the bonding wire, to the insulating tape and the resin proceeding to the adjacent internal lead in front of the adjacent internal lead.

[Brief description of the drawings]

FIGS. 1A and 1B are a plan view and a cross-sectional view taken along line AOA ′ of a lead frame showing a first embodiment of the present invention.

FIGS. 2 (a) and 2 (b) are a plan view and a cross-sectional view taken along the line BB ′ of a lead frame showing a second embodiment of the present invention.

FIGS. 3 (a) and 3 (b) are a plan view and a cross-sectional view taken along a line CQC 'showing an example of a conventional lead frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Island 2 Suspended lead 3 Internal lead 4 Step part 5 Insulating tape

Claims (2)

(57) [Claims] 1. An island, a suspension lead for holding the island, an internal lead disposed around the island, and a frame-shaped insulating member bonded to and connected to the upper surfaces of the internal lead and the suspension lead. With a tape,
In a lead frame in which the suspension lead is provided with a step portion and the island is arranged in a plane different from the plane including the internal lead, a step portion of the suspension lead is provided in the center of the insulating tape, From the center of the tape
Before the outer part is the upper part of the step part of the suspension lead
Adhered to the upper surface of the suspension lead,
The part inside from the center is above the step of the suspension lead.
The frame-shaped insulating tape that protrudes horizontally as it is
Insulating tape on the upper surface of the internal leads connected by
Are adhered on the entire inner and outer surfaces. 2. An island and holding the island
Suspension leads and the inside of the
Part lead, the inner lead and the upper surface of the suspension lead.
Having a frame-shaped insulating tape bonded and connected to each other,
Steps are provided on the suspension leads to include the internal leads
A leadframe in which the island is arranged in a plane different from the plane
In the frame, the insulating tape is cut off at the connection between the suspension lead and the internal lead, and the insulation tape is also
Features and to Brighter over lead frame in that the insulating tape is partially adhered to the surface.