JPH03212960A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a resin from flowing into a through hole by a method wherein the opening end part of the through hole is blocked up by using a coating hardened layer of an organic compound resist. CONSTITUTION:A coating hardened layer 17 of a resist ink is formed on a circuit board 10 around a semiconductor chip 13. The opening end on the surface side of through holes 12 is blocked up completely. Thereby, it is possible to prevent that an epoxy-resin sealing layer 18 formed at the upper part flows into the holes 12. Since the layer 18 is formed by a transfer molding method, pads 14 of an inserted semiconductor chip 13 and connecting wires 16 are not carried away by a pressed-into resin and are not destroyed and a good characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a semiconductor device in which a semiconductor element is mounted on a circuit board and the outside thereof is sealed with an insulating resin.

(Prior Art) In recent years, in the field of electronic devices, miniaturization and thinning have been progressing more and more, and this has become an important element for increasing the added value of products. Therefore, even in a semiconductor device in which a semiconductor element such as a semiconductor chip is mounted on a circuit board and the outside thereof is sealed with an insulating resin, the overall thickness is required to be as thin as possible.

Conventionally, as shown in FIG. 2, such a semiconductor device has a predetermined structure on a circuit board 3 on which a conductive circuit 1 is formed on the surface or inside and a plurality of through holes 2 passing through the front and back sides. The semiconductor chip 4 is directly die-bonded to the position using a conductive adhesive or the like, and the pads 5 of the semiconductor chip 4 and the lead frame 6 formed on the circuit board 3 are connected using wires 7 such as gold wires. Furthermore, a device is used in which a liquid insulating resin such as epoxy resin or silicone resin is potted (cast) on the outside of these, and the semiconductor chip 4 is hermetically sealed.

In such a semiconductor device, in order to make the overall thickness of the device as thin as possible, a sealing layer 8 of insulating resin is used.
An important issue is to make the thickness as thin as possible.

Therefore, we use a low viscosity liquid insulating resin,
In addition, during potting, a frame 9 is provided on the circuit board 3 around the semiconductor chip 4 so as to close the through hole 2 at the bottom to prevent the liquid insulating resin from flowing out around the through hole 2. Efforts are being taken to prevent the influx.

(Problem to be Solved by the Invention) However, in the conventional semiconductor device configured as described above, it is not only difficult to adjust the viscosity and injection amount of the liquid insulating resin, but also the upper surface of the sealing layer 8 There was a problem in that the surface was not smooth and had an unfavorable appearance.

The present invention was made to solve these problems, and semiconductor elements are encapsulated with an insulating resin layer that is thin and has good adhesion to the underlying circuit board, and has good appearance and characteristics. An object of the present invention is to provide a semiconductor device in which an insulating resin constituting a sealing layer is prevented from flowing into a through hole.

[Structure of the Invention] (Means for Solving the Problems) A semiconductor device of the present invention is provided at a predetermined position on a circuit board on which a conductive circuit is formed and a plurality of through holes are formed through the front and back sides. In a semiconductor device in which a semiconductor element is mounted and the outside of the semiconductor element is sealed with an insulating resin, a coated hardened layer of an organic compound resist is provided on the circuit board around the mounting part of the semiconductor element. The sealing layer made of the insulating resin is formed by transfer molding of a thermosetting resin.

(Function) In the semiconductor device of the present invention, a hardened coating layer of an organic compound resist is provided on the circuit board around the portion where the semiconductor element is mounted, and this hardened coating layer is applied to at least the surface of the through hole. Since it is embedded in the open end of the side, the through hole is completely closed.

Therefore, the thermosetting resin in a fluid state that is transfer-molded from above the mounted semiconductor element does not flow into the through hole.

In addition, since the sealing layer made of insulating resin is formed by transfer molding of thermosetting resin, the thickness of the sealing layer can be reduced compared to conventional semiconductor devices in which this layer is formed by botting. It can be made thinner, and the entire device can be made smaller and thinner.

Furthermore, since most of the sealing layer is provided on the coated and cured layer of organic compound resist, the adhesion between the sealing layer and the circuit board is improved.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a cross-sectional view showing an embodiment of the semiconductor device of the present invention.

In the figure, reference numeral 10 indicates a circuit board on which a conductive circuit 11 is formed by etching copper foil or the like, and a plurality of through holes 12 are provided through the front and back sides. A semiconductor chip 13 is die-bonded with a conductive adhesive (not shown).

And the pad 14 of this semiconductor chip 13 and the circuit board 1
The lead frame 15 on the top of the lead frame 15 is electrically connected by a wire 16 such as a gold wire.

Further, in this way, a thermosetting or UV (ultraviolet) curing organic compound resist is applied to the area around the semiconductor chip 13 on the circuit board 10, that is, on the circuit board 10 excluding the die-bonding part of the chip and the lead frame 15. A coating hardening layer 17 of ink is provided. The lower part of the cured coating layer 17 is embedded into the through hole 12 from its open end, and the open end of the through hole 12 on the surface side is completely closed by the cured coating layer 17.

Further, on the outside of the semiconductor chip 13, a sealing layer 18 made of epoxy resin is formed by a transfer molding method as shown below, spanning over a coated and cured layer 17 of resist ink provided around the semiconductor chip 13. .

That is, a rectangular formwork equipped with heating means is placed on the coated and cured layer 17 of resist ink around the semiconductor chip 13, and the epoxy resin, which has been heated and plasticized in a chamber (pot) in advance, is placed in this form. The sealing layer 18 is formed by press-fitting and transferring it into the cavity of the frame using a plunger, and then heating and curing it.

In the semiconductor device of the embodiment configured in this way,
A cured coating layer 17 of resist ink is provided on the circuit board 10 around the semiconductor chip 13, and the cured coating layer 17 completely closes the opening end of the through hole 12 on the surface side. The sealing layer 18 formed of epoxy resin does not flow into the through hole 12.

Furthermore, since the sealing layer 18 made of epoxy resin is formed by a transfer molding method, the pad 14 of the inserted semiconductor chip 13 and the wires 16 connecting it to the circuit board 10 are press-fitted. There is no chance of it being suppressed by the resin and breaking. Further, since a molded body having uniform quality is formed, a semiconductor device with good characteristics can be obtained.

Furthermore, compared to conventional semiconductor devices in which such a sealing layer 18 is provided directly on the circuit board 10 by potting, the adhesiveness between the sealing layer 18 and the circuit board 10 is excellent, and the mechanical strength of the entire device is improved. It's improving.

Furthermore, since the thickness of the sealing layer 18 can be made as thin as possible, the entire semiconductor device can be made smaller and thinner.

[Effects of the Invention] As explained above, in the semiconductor device of the present invention, a coated hardened layer of an organic compound resist is provided on the circuit board around the mounted semiconductor element, and this coated hardened layer Since the opening end of the through hole is closed, the sealing insulating resin is prevented from flowing into the through hole.

In addition, most of the sealing layer made of such insulating resin is
Since it is provided on the cured coating layer, the adhesiveness between the sealing layer and the circuit board is good, and the mechanical strength of the entire device is improved.

Furthermore, since the sealing layer is formed by transfer molding, the thickness of the sealing layer can be reduced, and the entire semiconductor device can be made smaller and thinner.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the semiconductor device of the present invention, and FIG. 2 is a cross-sectional view illustrating a conventional semiconductor device. 10......Circuit board 11...Conductive circuit 12...Through hole 13...Semiconductor chip 16.・・・・・・Wire

Claims (1)

[Claims] (1) A semiconductor element is mounted at a predetermined position on a circuit board on which a conductive circuit is formed on the front surface and a plurality of through holes are formed passing through the front and back sides, and the outside of the semiconductor element is covered with an insulating resin. In the semiconductor device sealed by the semiconductor device, a coated and cured layer of an organic compound resist is provided on the circuit board around the mounting portion of the semiconductor element, and the sealing layer made of the insulating resin is heat-cured. A semiconductor device characterized in that it is formed by transfer molding of a synthetic resin.