JPH02105545A - Manufacture of resin sealed semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the cost by eliminating the wasteful use of a good semiconductor pellet by fixing the semiconductor pellet and forming a wiring after effecting resin-sealing, leaving behind spaces needed for a region of a lead frame where the semiconductor pellet is mounted and a wiring region. CONSTITUTION:An island 2 of a lead frame and the tip end of an internal lead 4 are exposed, and the surroundings of the exposed portions are sealed by exterior sealing resin 1. Then, an external lead 3 is molded by a finishing process, and a semiconductor pellet 6 is subjected to die-bonding onto the island 2 using silver paste and the like. Thereupon, the internal lead 4 and the bonding pad of the semiconductor pellet 6 are connected through a bonding wire. Further, said portion surrounded by the exterior sealing resin 1 is sealed with interior sealing resin 8. Hereby, a resin-sealing type semiconductor device is completed. Since the exterior resin formation process and the finishing process are performed prior to the die-bonding process, use of semiconductor pellet is eliminated in the resin formation process and the finishing process to reduce the cost of the device.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing a resin-sealed semiconductor device.

[Conventional technology]

Conventionally, resin-sealed semiconductor devices have been made by fixing a semiconductor pellet to an island of a lead frame with silver paste, etc., connecting the lead and the bonding pad of the semiconductor pellet with wire bonding, and then molding the semiconductor pellet with resin. After sealing, finishing touches such as cutting tie bars and forming leads were performed.

[Problem to be solved by the invention]

In recent years, the unit price of semiconductor pellets has become higher due to higher integration of semiconductors, and the ratio of the price of semiconductor pellets to the price of the entire resin-sealed semiconductor device has increased. Therefore, defects in the encapsulation process and finishing process of the resin-sealed semiconductor device result in the waste of good semiconductor pellets, which has the drawback of increasing costs.

[Means to solve the problem]

The method for manufacturing a resin-sealed semiconductor device of the present invention leaves space at least in the semiconductor pellet mounting area of the board frame having the leads connected to tie bars and in the wiring area for connecting the leads and bonding pads. a step of sealing the lead frame with resin, a step of fixing a semiconductor pellet in the semiconductor pellet mounting area and then forming a wiring between the lead and the bonding pad, and a step of sealing the space in which the semiconductor pellet is mounted and the wiring is formed. The method includes a step of resin sealing.

〔Example〕

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

FIGS. 1(a) and 1(b) are a plan view and a cross-sectional view taken along the line AA' of a lead frame partially sealed with resin for explaining a first embodiment of the present invention.

First, the island 2 and the inner part of the lead frame have an island 2 connected to a suspension lead 3, and an inner lead 4 and an outer lead 5 connected around this A/F land 2 by a tie bar (not shown). The tips of the leads 4 are exposed, and the periphery thereof is sealed with an external sealing resin 1.

Next, the external leads 5 are formed in a finishing process. This molding may be performed before sealing with the external sealing resin.

Next, after die-bonding the semiconductor pellet 6 onto the island 2 using silver paste or the like, the internal lead 4
and the bonding pads of the semiconductor pellet 6 are connected by a bonding wire.

Next, the portion surrounded by the outer sealing resin 1 is sealed with the inner sealing resin 8, thereby completing a resin-sealed semiconductor device. The internal sealing resin 8 used here may be the same as the external sealing resin 1 or may be different.

However, for example, if a resin for alpha ray protection is used, a resin-sealed semiconductor device that is resistant to alpha rays can be made, and if a moisture-resistant resin is used, a resin-sealed semiconductor device with excellent moisture resistance can be made. can get.

According to the first embodiment, since the external resin forming process and finishing process are performed before the die bonding process, there is no need to use semiconductor pellets for defective products in the resin forming process and finishing process, which reduces costs. is reduced.

In addition, for lead frames with thin and long internal leads such as multi-pin quad flat packages, the internal leads can be fixed by resin formation before Gui bonding. It is also possible to prevent thermal deformation of the internal leads due to paste baking and heating during the wiring process, thereby improving yield.

FIG. 2 is a plan view of a lead frame partially sealed with resin for explaining a second embodiment of the present invention.

In this second embodiment, since a lead frame without hanging leads and islands is used, the pellet mounting portion 7
is the surface of the external sealing resin 1.

That is, after the external sealing resin is formed in the same manner as in the first embodiment, the semiconductor pellet 6 is fixed to the pellet attachment portion 7 using pellet adhesion means such as silver paste. Next, the internal leads 4 and the bonding pads are wire-bonded with a bonding wire, and then sealed with an internal sealing resin.

In the case of the second embodiment, since there is no hanging lead, the width of the internal lead 4 can be made slightly thicker, which is advantageous when increasing the number of pins, and is also advantageous in terms of moisture resistance of the package.

〔Effect of the invention〕

As explained above, the present invention enables the semiconductor pellet mounting area and the wiring area of the lead frame to be sealed with resin while leaving the necessary space, and then the semiconductor pellet is fixed and the wiring is formed, thereby eliminating the conventional encapsulation process. Also, since good semiconductor pellets are not wasted due to defects occurring in the finishing process, there is an effect that costs can be reduced.

[Brief explanation of the drawing]

1(a) and 1(b) are a plan view and a cross-sectional view taken along line A-A' of a partially resin-sealed lead frame for explaining the first embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA' of the present invention. FIG. 3 is a plan view of a partially resin-sealed lead frame for explaining a second embodiment of the present invention. 1... External sealing resin, 2... Island, 3...
Hanging lead, 4... Internal lead, 5... External lead, 6... Semiconductor pellet, 7... Pellet mounting part,
8... Internal sealing resin.

Claims (1)

[Claims] a step of sealing the lead frame with a resin leaving a space between at least a semiconductor pellet mounting area of a lead frame having leads connected to tie bars and a wiring area for connecting the leads and bonding pads; and a step of sealing the lead frame with a resin, and said semiconductor pellet mounting area. Resin sealing characterized by comprising the steps of: forming a wiring between the lead and the bonding pad after fixing a semiconductor pellet to the semiconductor pellet; and sealing with resin the space in which the semiconductor pellet is mounted and the wiring is formed. A method for manufacturing a type semiconductor device.