JPH06101486B2 - Adhesive mounting method for semiconductor chips - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an adhesive attachment method for a semiconductor chip, which enables easy and highly accurate adhesive attachment.

[Technical background of the invention and its problems] Conventionally, when a semiconductor chip is attached to an attached body such as a lead frame or a substrate, a liquid conductive or insulating adhesive is applied to the adhered portion of the attached body. The method of adhering semiconductor chips has been adopted. That is, as shown in FIG. 2, many elements 12 are formed on the semiconductor wafer 11.
The surface of the semiconductor wafer 11 is scraped with a dicer. Subsequently, a vinyl chloride sheet is attached to the front surface and the back surface of the wafer and pushed up from the back surface side by a roller or the like, and divided into a large number of chips along the scrape line. Next, the vinyl chloride on the upper surface is peeled off, and the vinyl chloride sheet on the lower surface is stretched in all directions to separate into semiconductor chips. The semiconductor chip 12 thus separated is mounted on the lead frame in the order of steps as shown in FIG. As shown in FIG. 3 (X), a silver plating layer 14 is formed on the lead frame 13, and a liquid conductive or insulating adhesive 15 is applied to the adhesive portion on the silver plating layer 14. Apply. Continuing,
As shown in FIG. 13 (Y), the semiconductor chip 12 separated by the above method of FIG. 2 is placed on the adhesive and heat-bonded.

However, in this adhesive attachment method, a method such as stamping or potting with a dispenser was adopted to apply the liquid adhesive onto the lead frame, but there were the following problems.

(1) In the case of a conductive adhesive, the dispersion of the conductive substance is likely to be non-uniform, which adversely affects the physical properties.

(2) After the adhesive is applied, the resin spreads and the bleeding varies widely, and it is difficult to perform high-density mounting.

(3) Due to variations in the viscosity of the adhesive, it is difficult to adjust the coating amount and coating area with high precision.

(4) Since an expensive coating device is required, the coating processing cost becomes high.

[Object of the Invention] The present invention has been made to solve the above-mentioned problems, and the object thereof is to make the amount and thickness of the adhesive uniform, to improve high-density mounting, and An object of the present invention is to provide a method for adhesively attaching a semiconductor chip in which an additive substance is uniformly dispersed, physical properties are improved, and highly accurate adhesion can be easily performed without requiring an expensive device.

[Summary of the Invention] The present inventor has completed the present invention by discovering that the sheet with an adhesive can be used for easy and accurate adhesive attachment as a result of intensive studies to achieve the above object. Is. That is, the present invention relates to a method of adhesively attaching a semiconductor chip to an object to be attached, wherein a thermoplastic film surface is bonded to an object to be attached, by applying an adhesive-coated sheet obtained by applying an adhesive on a thermoplastic film to a semi-cured state. The semiconductor chip is bonded and attached by thermocompression bonding and melting and curing, and then the semiconductor chip is placed on the adhesive surface of the adhesive-bonded sheet that has been pressure bonded as described above.

The semiconductor chip used in the present invention may be of any type and shape and is not particularly limited and can be widely applied.

The thermoplastic film used in the present invention has a softening point of 15
It is desirable that the thickness is 0 ° C. or less and the thickness is several tens of μm or less. Specific films include nylon, tetron, polypropylene and the like.

The adhesive used in the present invention is not particularly limited, and may be conductive or insulating, and the resin component is preferably thermosetting. An adhesive is applied on the thermoplastic film to make it a semi-cured state. The amount of the adhesive applied is appropriately selected according to the size of the semiconductor chip to determine the amount applied. The sheet with an adhesive thus obtained is cut into the same size as the semiconductor chip.

Embodiments of the Invention The present invention will be specifically described below with reference to the drawings. FIG. 1 is described with reference to explanatory views showing a method of adhesively attaching a semiconductor chip in the order of steps. As shown in FIG. 1 (A), a semi-cured adhesive 1 is used as an adhesive-attached sheet formed on a thermoplastic film 2 as shown in FIG. 1 (B). The sheet is cut and divided into almost the same size as the semiconductor chip to be bonded. This thermoplastic film 2 has a thickness of several tens of μ.
It is desirable that the softening point at m is 150 ° C or lower. The thickness of the film is appropriately selected and used according to the size and shape of the semiconductor chip. When the softening point of the film exceeds 150 ° C., other properties are adversely affected, and heating is not easy, which is not preferable. Next, as shown in FIG. 1 (C), the adhesive 1 surface of the sheet with the adhesive divided is adsorbed by the vacuum adsorbing means 5 (C-2 stage) and silver-plated on the lead frame 3 preheated by the preheater 9. Lightly thermocompression-bond onto the pattern 4 (C-1 stage). Then, the thermoplastic film 2 is softened and temporarily adhered to the silver plating pattern 5. Next, as shown in FIG. 1 (D), the semiconductor chips 6 separated on the vinyl chloride sheet 7 are adsorbed by the vacuum adsorption means 5 and separated from the vinyl chloride sheet 7 (D-2 stage). In this case, the push-up rod 8 is slightly pushed up from below the vinyl chloride sheet to further facilitate the separation of the semiconductor chip 6 from the vinyl chloride sheet 7. Vacuum suction means 5
The semiconductor chip 6 adsorbed on is strongly thermocompression bonded to the adhesive 1 surface on the thermoplastic film 2 which is thermocompression bonded onto the silver plating pattern 4 of the lead frame 3 preheated by the preheater 9 (D-1 stage ). The semi-cured adhesive 1 and the thermoplastic film 2 are melt-cured, and the semiconductor chip 6 can be firmly adhered and attached.

Although the case where the semiconductor chip is bonded to the lead frame is shown here, the body to be mounted is not limited to this, and may be an insulating substrate, a substrate with an electrode pattern, or the like.
Further, as the adhesive, an appropriate one such as conductivity, insulation, or heat conductivity is selected and used according to the necessary conditions and state. The semiconductor chip is not limited to the IC, and other types of semiconductor chips can be attached by adhesion.

[Advantages of the Invention] According to the adhesive mounting method for a semiconductor chip of the present invention, since the sheet with an adhesive is used and the die bonding is carried out instantly, the spread and bleeding of the resin are prevented and the high-density mounting is improved. To be done. Further, the additive substance in the adhesive is uniformly dispersed, the characteristics of the physical characteristics are reduced and the characteristics are improved, and it is possible to adhere to a large number of pieces at once, without the need for an expensive coating device like the conventional one. There are merits such as reduction of manufacturing costs and equipment costs.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a method of mounting a semiconductor chip according to an embodiment of the present invention in the order of steps, FIG. 2 is a perspective view of a semiconductor wafer, and FIG. 3 is a main step of a conventional method of bonding and mounting a semiconductor chip. It is explanatory drawing shown in order. 1 ... Adhesive, 2 ... Thermoplastic film, 3 ... Lead frame, 4 ... Silver plating pattern, 5 ... Vacuum suction means, 6 ... Semiconductor chip, 7 ... Vinyl chloride sheet, 8
…… Pusher rod, 9 …… Preheat heater.

Claims (1)

[Claims] 1. A method of adhesively attaching a semiconductor chip to a body to be attached, wherein a thermoplastic film surface is joined to a body to be attached with an adhesive-attached sheet obtained by applying an adhesive agent on a thermoplastic film to give a semi-cured state. A method for adhering and attaching a semiconductor chip, which comprises placing the semiconductor chip on the adhesive surface of the adhesive-attached sheet, then thermocompression-bonding and melt-curing.