JPH02165996A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the generation of the warpage of a semiconductor device by forming a through-hole in an insulating layer shaped by covering a substrate surface with a photosensitive film and executing a printed wiring. CONSTITUTION:Conductive adhesives 2 are placed on both recessed surfaces of a support base body 1 being composed of an insulating material and having recessed sections 50, 51 in both surfaces thereof, a plurality of IC chips 3 are inserted, and adhesives 4 are introduced into the clearances of the IC chips 3 and the substrate 1 and fixed while the IC chips 3 are brought near to one side as a reference. Photosensitive films 5 are applied onto both surfaces through thermocompression bonding respectively, and the photosensitive films 5 on both surfaces are exposed through ultraviolet- light irradiation by using a photomask, to which the patterns of through-holes 6 and substrate-terminal connecting patterns are shaped, in the films 5. A developer is sprayed against surfaces to be exposed and development treatment is executed, thus forming the through-holes 6, then shaping insulating surfaces through drying and curing. Wirings 7 are shaped to the surface and the rear through printing respectively, the electrode terminals of the IC chips 3 and substrate electrode terminals are connected, and the wirings 7 are led out of both surfaces of the substrate 1 at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention particularly relates to a semiconductor device suitable for a memory card mounted with an IC memory chip.

(Prior art) Recently, as an external storage device for data of electronic computers, etc.
2. Description of the Related Art Semiconductor devices equipped with a plurality of memory integrated circuits (hereinafter referred to as memory ICs) have been developed.

As a method of mounting a memory IC in this semiconductor device, a packaged memory IC is placed on a printed circuit board, and the lead terminals of this IC are soldered to the wiring pattern of the printed circuit board, or a bare memory IC is mounted on the printed circuit board. IC
A commonly used method is to mount a chip (hereinafter referred to as an IC chip) on a printed circuit board and then connect the bonding pads of the IC chip to the wiring pattern of the printed circuit by wire bonding.

By the way, as another mounting method, Fig. 3 (a) and (b)
In order to arrange a plurality of IC chips 11 with high relative positional accuracy as shown in FIG. Insert IC chip 11 and glue 1
A photosensitive film 16 that is fixed with 4 or the like to form a substantially coplanar shape and has an opening 15 for a through hole on this plane.
A method has been proposed in which insulating layers such as those described above are laminated as necessary and an electric circuit is created using printed wiring 17.

This mounting method uses bare IC chips rather than packaged ICs, so the cost of the parts used is low;
It has the advantage of not requiring a chip mount device or wire bonding device with high positioning accuracy.

However, when this method is used, since the insulating layer is formed on one side, the thermal stress due to thermocompression bonding is applied only to one side, which tends to cause warping of the semiconductor device.To prevent this, the back side is reinforced with an area equivalent to the chip mounting area. Measures such as installing a board will be required.

(Problem to be Solved by the Invention) Since the insulating layer of a semiconductor device is only on one side by the conventional method, warping occurs due to thermal stress when thermocompression bonding is applied to attach a photosensitive film. The purpose of this method is to prevent warpage of semiconductor devices by simultaneously applying photosensitive films to both sides of a device substrate frame by thermocompression bonding.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a semiconductor device in which a plurality of integrated circuit (IC) chips are arranged on a substrate substantially on the same plane, and the IC chips are wired. This is a semiconductor device in which through holes are provided in an insulating layer formed by applying a photosensitive film to a substrate surface, and then printed wiring is applied.

(Function) By forming insulating layers on both sides of the substrate frame as in the present invention, it is possible to prevent warping of the semiconductor device. Furthermore, by forming through holes similar to those on the front surface of the insulating layer on the back surface of the substrate and wiring them, it becomes possible to draw out the wires from both sides.

(Example) FIG. 1 is a plan view and a cross-sectional view showing the manufacturing process of a semiconductor device according to an example of the present invention.

First, as shown in FIGS. 1(a) to (d), a supporting base (hereinafter referred to as a substrate) is made of an insulating material such as glass epoxy or ceramics and has recesses 50 and 51 on both sides.
A conductive adhesive 2 is placed on both concave surfaces of 1, and an IC chip (3
) After inserting a plurality of chips, an adhesive 4 such as a resin is put into the gap between the IC chip and the board, filling the gap and fixing the IC chip, while moving the IC chip to one side as a reference.

Furthermore, as shown in FIGS. 1(θ) and (f), a photosensitive film 5 to be used as an insulating layer is adhered to both sides by thermocompression bonding, and the IC chip electrode terminal portion and wiring portion are covered with the photosensitive film 5. Using a photomask such as a metal mask in which a pattern of through-holes 6 for connection to the board and board terminal connection no-turns are formed at arbitrary positions, the photosensitive film 5 on both sides is exposed using an ultraviolet irradiation device such as an exposure machine. Perform exposure.

Next, as shown in FIGS. 1(g) and 1(h), the through holes 6 are developed by spraying a solvent type developer onto the exposed surface and the entire surface.
After forming, dry and harden to form an insulating surface.

Next, wiring 7 is formed by printing on each of the front and back surfaces to connect the electrode terminals of the IC chip and the electrode terminals of the substrate, and the wiring is drawn out from both sides of the substrate.

FIG. 2 is a plan view and a sectional view showing another embodiment of the present invention.

First, as shown in FIGS. 2(a) and 2(b), a support base (hereinafter referred to as a substrate) 61 having an opening 60 made of an insulating material such as glass epoxy or ceramics is coated with a heat-resistant material on one side. An adhesive tape 62 is pasted to cover the opening, and a heat-resistant adhesive tape 83 having a shape corresponding to the opening 60 is further pasted. A conductive adhesive 64 is placed on the surface of this tape 63 at key points.

Next, as shown in FIGS. 2(e) and 2(d), a plurality of IC chips 65 are inserted into positions corresponding to the conductive adhesive 64 placed on the bottom surface with the opening facing up, and placed on one side as a reference. IC
While bringing the chips together, an adhesive 66 such as a resin is put into the gap between the IC chip 65 and the end surface of the opening of the substrate 61, filling the gap and fixing the IC chip 65.

Furthermore, as shown in FIG. 2(e), a photosensitive film 67 to be used as an insulating layer is adhered to the upper surface of the supporting base 61 by thermocompression bonding, and a heat-resistant film 67 is attached to the back surface of the substrate B1. Peel off the photosensitive tape 62 and remove the photosensitive film 68.
Using a photomask such as a metal mask with through holes formed to connect to the IC chip electrode terminals and wiring parts, both sides of the board are coated by thermocompression bonding using an ultraviolet irradiation device such as an exposure machine. Expose the photosensitive film.

Next, as shown in FIGS. 2(f') and (g), through-holes 69 are formed and dried by performing a developing process by spraying a solvent type developer over the entire surface to be exposed. , and harden to form an insulating layer surface. Next, as shown in FIGS. 2(h) and (I), the base 61
By forming printed wiring 70 on the front and back sides of the substrate by printing, wiring was drawn out from both sides of the substrate.

[Effects of the Invention] By forming insulating layers on both sides of the semiconductor device, warpage is prevented, and wiring can be drawn out from both sides. Furthermore, as shown in the embodiments, by mounting IC chips on both sides of a semiconductor device, the degree of integration of the IC chips can be greatly increased compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a manufacturing process diagram showing an embodiment of the present invention, FIG. 2 is a manufacturing process diagram showing another embodiment of the invention, and FIG. 3 is a diagram explaining a conventional device. DESCRIPTION OF SYMBOLS 1... Support base, 2... Conductive adhesive, 3... IC chip, 5... Photosensitive film, 6... Through hole, 7... Wiring. Agent Patent Attorney Noriyuki Chika Yudo Mitsuyuki Matsuyama Figure 1! Figure 2

Claims (2)

[Claims] (1) A semiconductor device in which a plurality of integrated circuit chips are arranged on a substrate substantially on the same plane and the integrated circuit chips are wired, and the semiconductor device is formed by covering the entire surface of the substrate with a photosensitive film. A semiconductor device characterized in that printed wiring is applied after providing through holes in an insulating layer. (2) The printed wiring method is used to place the entire effective area on both sides of the board, and the wiring is drawn out from both sides to increase the degree of integration of the integrated circuit chip, and the integrated circuit chips are placed on both sides. The semiconductor device according to claim 1.