JPS61292328A - Manufacture of semiconductor sealing structure - Google Patents

Abstract

PURPOSE:To obtain a sealing structure of an organic resin layer without resin stopper by using resin flow restricting material layer such as silicone grease or oil and deciding the profile of the resin layer with the surface tension of the resin. CONSTITUTION:A resin flow restricting material layer 17 made of silicone grease is formed substantially in a square loop shape to surround a chip 14 in space on the surface of a substrate 11 to which wirings 15 are bonded completely. Then, epoxy resin is supplied by potting on the surface of the substrate inside the layer 17. A heat treatment of 150 deg.C for 30min is, for example, executed in the state that the resin is restricted to expand by the layer 17 to hold the shape by the surface tension to harden the resin, thereby forming an organic resin layer 16 for coating and sealing the chip 14. Thereafter, a cleaning with trichloroethylene is applied to remove the layer 17.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a semiconductor encapsulation structure in which a semiconductor chip is mounted on an insulating substrate and sealed with an organic resin layer.

The first semiconductor device of this type that has been proposed in the past is
There is something like the one shown in the figure. In FIG. 1, reference numeral 1 denotes an insulating substrate generally referred to as a printed circuit board, on the surface of which a large number of wiring layers 2 are formed, as well as recesses. A semiconductor chip with a built-in integrated circuit is fixed in the recess of the substrate 10 by a suitable adhesive layer 3, and a large number of electrodes on the chip Φ are electrically connected to the corresponding wiring layer 2 via bonding wires 5. There is. Then, a resin stopper 6 is attached to the surface of the substrate 100 with an adhesive so as to surround the chip 4 at a distance, and the inside of this stopper 6 is filled with organic resin rgI7 to seal the chip 4 permanently. It has become.

However, such a semiconductor device has the following problems.

(1) Since the register/stomper 6 is formed and attached to the substrate 10, material costs, processing costs, installation costs, etc. are required accordingly, resulting in an increase in the cost of the device.

(2) When forming the organic resin layer 7, the resist/stopper 6 regulates the flow of the resin and also regulates the thickness of the resin, so the organic resin layer 7 corresponds to the thickness of the stopper 6. However, it becomes bulky and difficult to make the device thin and compact.

(3) It is necessary to secure a special installation space to provide the resin stopper 6, which reduces the usable area on the substrate surface and the degree of freedom in layout.

In order to solve the problem (3) above, it is possible to remove the resin stopper 6 after forming the organic resin layer 7, but in this case, the step-like edge of the organic resin layer 7 may be removed during handling. There are problems in that the parts are easily damaged, which increases the frequency of appearance defects and impairs the airtightness of the seal, reducing the reliability of the device.

An object of the present invention is to provide a novel method for manufacturing a semiconductor encapsulation structure that solves the various problems described above.

The present invention is characterized in that the outer shape of the organic resin layer is determined by using a resin flow regulating material layer such as silicone grease or silicone oil and by using the surface tension of the resin. The embodiment shown in will be described in detail.

FIG. 2 shows an embodiment in which the present invention is applied to an integrated circuit device for a watch module, and 11 is an insulating substrate made of, for example, glass cloth impregnated with epoxy resin;
Reference numeral 12 denotes a large number of wiring layers formed by patterning Cu foil adhered to the substrate 10 using photolithography technology and then applying Cu plating, Ni plating, and Au plating.

A semiconductor (silicon) chip 14 with a built-in integrated circuit is fixed to the bottom surface of the recess provided in the substrate 11 with an adhesive layer 13 made of epoxy adhesive or Ag paste, and a large number of electrodes on the chip 1Φ are connected using an ultrasonic method, for example. It is electrically connected to the corresponding wiring layer 12 by a bonding wire 15 that is passed through nail head bonding. An organic resin layer 16 made of epoxy resin is formed on the substrate 11 so as to cover the chip 14, the bonding wires 15, and the ends of the wiring layer 1z.

This organic resin layer 16 is for covering and sealing the chip 14, and terminates on the substrate surface in a smooth spherical shape formed by surface tension when its spread is restricted during flow. Has characteristics.

Here, the manufacturing process of the device shown in FIG. 2 will be explained with reference to FIG. 3a. First, as shown in FIG.
A resin flow guide material layer 17 made of silicone grease is formed in a substantially rectangular loop shape so as to surround and space apart from each other.

For this purpose, it is preferable to use, for example, an instrument that can adsorb silicone grease in a pattern corresponding to the layer 17 and then press it directly onto the surface of the substrate 110 to transfer or apply it.

°°Next, as shown in Figure 3b, the resin flow regulating material layer 1
Epoxy resin is supplied onto the inner surface of the substrate 7 by potting. Then, while the epoxy resin is restrained from spreading by the regulating material layer 17 and its shape is maintained by surface tension, heat treatment is performed for about 30 minutes to harden the epoxy resin. By doing this, an organic resin layer (a portion with a mesh) 16 that covers and seals the chip 14 is formed.The organic resin layer 16 formed in this way has a preferable smooth outer shape as shown in FIG. becomes.

Thereafter, as shown in FIG. 3c, a cleaning treatment using, for example, trichlorethylene is applied to remove the register/flow regulating material layer 17 made of silicone grease.

The reason why the resin flow regulating material layer 17 is removed in this way is that if it remains, the installation space cannot be used freely, the appearance is unfavorable, and it adheres to the wiring layer on the board, resulting in poor conductivity. This is because there is a risk that the product may cause damage to the product, and that it may adhere to workers or other parts during handling.

FIG. 4 shows another embodiment in which the present invention is applied to a hybrid integrated circuit device, in which 21 is an insulating substrate made of ceramics, 22 is a large number of wiring layers formed on the surface of the substrate 210, and 23 is, for example, An adhesive layer 24 made of a metal brazing material is fixed to the surface of the substrate 21 by an adhesive layer 23. A semiconductor chip 25 with a built-in integrated circuit connects a large number of electrodes on the chip 24 to the corresponding wiring layer 22! The bonding wires 26 are organic resin layers formed to encapsulate the chip 24 in a manner similar to that described above with respect to FIGS. 3a-3c.

In addition, in the above-mentioned embodiment, as the resin regulating material layer 17, silicone oil can also be used in addition to silicone grease. These silicone greases, silicone, and silicone oils are suitable for carrying out the present invention because they can reach the heat treatment temperature of the resin.
However, the material is not limited to these materials, and other materials that can regulate resin flow and withstand heat treatment temperatures may be used. Also, as a material for the organic resin layer 16.26,
In addition to thermosetting resins such as epoxy resins, suitable thermoplastic resins may also be used.

As detailed above, according to the present invention, there is no need to use a resin stopper as an assembly component, so it is possible to significantly reduce costs, the device can be made thin and compact, and the Excellent functions and effects can be obtained, such as increased usable area and freedom of layout, and the smooth shape of the edges of the organic resin layer, which makes them less likely to be damaged, making it less likely that defects in appearance or deterioration in reliability will occur. It is something.

[Brief explanation of the drawing]

1 is a sectional view of a conventional semiconductor device, 2) is a sectional view of a semiconductor device according to an embodiment of the present invention, and 3a to 8c show the manufacturing process of the device of FIG. 2. FIG. 4 is a sectional view showing a semiconductor device according to another embodiment of the present invention. 1.11.21... Insulating substrate, 2.12.22...
・Wiring layer, 3.13.23...Adhesive layer, small, 14.
24... Semiconductor chip, 5.15.25... Bonding wire, 16, 26... Organic resin layer, 17.
...Resin flow regulating material layer. Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] 1. A step of preparing an insulating substrate on which a semiconductor chip is fixed and a number of electrodes of the chip are electrically connected to corresponding wiring layers on the surface, and separating the chip on the surface of the substrate. forming a resin flow regulating material layer in a pattern surrounding the chip; and supplying a fluidized organic resin material on the surface of the substrate inside the resin flow regulating material layer so as to cover the chip. The supplied organic resin material covers and seals the chip by curing the organic resin material in a state where its spread is regulated by the resin flow regulating material layer and its shape is maintained by surface tension. A method for manufacturing a semiconductor encapsulation structure, comprising the step of forming a resin layer.