JPH02228046A - Film carrier - Google Patents

Abstract

PURPOSE:To prevent not only bending of inner leads but also occurrence of variability of plating thickness by providing a frame material which interconnects inner leads at each tip of the inner leads and also be erecting reinforcing materials in a body together with the frame material inside the frame material. CONSTITUTION:In a film carrier 100, a frame material 13 for interconnecting inner leads 12a one another at each pointed end of the inner leads 12a is provided so that respective independent inner leads 12a are interconnected and reinforced one another or an electric current that flows concentrately in the case of performing electrolytic plating at each pointed end of the inner leads 12a may escape. Besides, reinforcing materials 14 are erected in a body together with the frame material inside of the frame material 13. It may be as well to form simultaneously these frame material 13 and reinforcing materials 14 when conductor circuits 12 are formed by etching metal foils pasted to a film 10. In this way, no inner leads are bent and variability of plating thickness is thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a film carrier used for mounting electronic components, and more particularly to a film carrier whose inner leads protrude toward device holes in the film.

(Prior art) A film carrier forms a conductive circuit on a film L,
It is configured as a terminal or the like for electrically connecting an electronic component to one end of this conductor circuit and connecting the other end of the conductor circuit to the outside. This film carrier can reliably mount extremely high-density electronic components, and has been widely used in recent years as a form of mass production of electronic component devices and packages.

In general, this film carrier is often constructed in the shape shown in FIGS. 210) formed in the device hole (z
t H, and this protruding part is used as an inner lead (212a), and each conductor circuit (21
2) The other end is extended to the outside of the device hole (second eye), and this is used as the outer lead (2] 2b). Note that the film (210) located below the outer lead (212b) ) is also formed with an opening, and the outer reel (212b) is formed so as to bridge over this device hole. These outer REITs (
212b) and the film (210) to obtain - independent film carriers (200).

Such a film carrier (200) is manufactured by the following method.

First, device holes (211) are formed as shown in FIG. 9(b) in a film (210) made of polyimide or the like as shown in FIG. 91:1(a).

Next, as shown in fjSQ diagram (c), a conductor circuit (212
) is attached to the film (210).

Next, as shown in FIG. 9(d), after forming an etching resist layer (216) and a back coat resin layer (217) in a predetermined shape on the metal foil (215),
By etching 5), a large number of electrically independent conductor circuits (212) are formed.

Finally, as shown in FIG. 9(e), the etching resist layer (216) and the back coat resin layer (217) are removed, and each conductor circuit (212) is removed as shown in FIG. 9(f).
A film carrier (2) having an inner lead (212a) is formed by forming a plating layer (218) on the surface of the film carrier (218).
■) will be completed.

However, in the conventional film carrier (200) manufactured by such a method, at the stage of forming the conductor circuit (212) by etching, the tips of the inner leads (212a) are separated from each other by independent free ends. Therefore, the etching resist layer (216)
And back coat resin layer (217)! ! The inner lead (212a) was frequently bent when the film carrier (R200) was transferred to the next process. Each inner lead (212
In contrast to a), C is an electronic component (20
) is connected, but if this inner lead r212a) has a bent part, the electronic component (20) cannot be connected properly.

Furthermore, when forming a plating layer on the inner lead (212a), an electrolytic plating method is generally adopted, but if the tips of the inner lead (212a) are independent free ends, this electrolytic plating method is During plating, the problem of current flowing concentratedly at the tip of the inner lead (212a), causing variations in the plating thickness, has become a problem.Therefore, conventional methods have sought to solve the following problems.

As shown in Figure 1O or Figure 11, the inner lead (
A film carrier (20 old) is known which is equipped with a frame (213) or an island part (219) that connects the tips of the two parts (212a). 20) is removed just before implementing.

In such a film carrier (200), since the tips of the inner leads (212a) are not independent free ends, when peeling off the etching resist layer (216) and the back coat resin layer (217), Alternatively, when transporting this film carrier (200) to the next process, the inner lead (212a) is difficult to bend at W. Further, during electrolytic plating, @79 does not flow intensively to the tip of the inner lead (212a), so that variations in plating thickness are prevented.

(Problem to be Solved by the Invention) However, the film carrier (20
In case 0), the strength of the frame (213) itself is insufficient, especially the center of each side of the frame (21:l) and the inner lead (212a) connected to this center. There was a problem with it bending.

In addition, the film carrier (20
In case G), when plating solution or cleaning solution is sprayed, more pressure is applied to the island part (219) than necessary, and the inner lead (212a) connected to this island part (219) is damaged. There was a problem with it bending.

The present invention has been made in view of the above circumstances, and its object is to provide a film carrier in which the inner leads do not bend and the plating thickness does not vary.

(Means for Solving the Problems) The means taken by the present invention to solve the problems as described above are as shown in FIGS. 1 to 5.
A film with device holes (U) for mounting (
A conductive circuit (12) is formed in the device hole (10), and one end of the conductive circuit (12) is made to protrude toward the device hole (11), and this protruding portion A film carrier that serves as an inner lead (12a) for electrically connecting a component (20).

A frame body (13) is provided at the tip of the inner lead (12a) and connects these together.
3) is characterized in that a reinforcing body (14) integral with the film carrier (rlO opening) is installed inside the film carrier (rlO opening), 1.

That is, the film carrier (100) according to the present invention aims to strengthen the independent inner leads (12a) by connecting them to each other, and to prevent the current from flowing intensively at the tips of the inner leads (12a). A frame (13) is provided at the tip of the inner lead (12a) to connect the inner leads (12a) to each other, and this frame (13) is
13) In order to increase the strength of the frame body (13), a reinforcing body (14) integral with the frame body (13) is installed inside the frame body (13).

The frame (I3) may be square as shown in FIGS. 3 and 4, or may be rectangular or circular, or may be connected to the V at the tip of the inner lead (12a). It can be of any shape.

In addition, the reinforcing body (14) has a frame body (14) as shown in FIG.
In addition to the structure in which the frame (13) is installed in a cross shape between the centers of the two opposing sides in 3), it may be installed in a mesh pattern between the two opposing sides of the frame (13) as shown in FIG. (I3) can be sufficiently reinforced, and the inner lead (12a) can be strengthened by the pressure applied when plating solution or cleaning solution is sprayed.
Any material may be used as long as it does not cause deformation. In addition, as shown in Fig. 3 and the fourth leap, the frame body (13
) is square, the center of each side is particularly prone to deformation, so a reinforcing body (1
4) is preferable.

These frame body (13) and reinforcing body (14) are made of a film (
When the conductor circuit (12) is formed by etching the metal foil (15) attached to the metal foil (15), it may be formed at the same time.

(Actions of the Invention) By adopting the above-described means, the present invention has the following effects.

By providing the mutually connected frame (13) at the tip of the inner lead (12a), when performing electrolytic plating, the current concentrated at the tip of the inner lead (12a) is transferred to the frame (13). Flow, inner lead (12a)
This prevents current from flowing concentratedly at the tip.

In addition, on the inside of the frame (11), there is also a physical reinforcement (
14), the strength of the frame (1 piece) itself is increased, and the frame body (1 piece) can be easily used when peeling off the etching resist layer (16) and back coat resin layer (17), or when transporting to the next process. The inner lead (12a) connected to the body (13) and this frame (I3) is prevented from bending. Furthermore, instead of blocking the inner opening of the frame (13), by reinforcing it by installing a reinforcing body (14), when spraying a plating solution or a cleaning solution, etc., the frame can be damaged by spray pressure. (13)
and an innerli 1 connected to this frame (13)
'(12a) is designed not to bend.

(Example) Hereinafter, the present invention will be described in detail according to an example shown in the drawings.

First, for the film (10) made of polyimide etc. as shown in M51A (a), t55 (b)
A device hole (11) was formed as shown in FIG.

As shown in FIG. 5(c), a metal foil (15) to become a conductive circuit (12) was attached to the film (l◎).

Next, as shown in FIG. 5(d), after forming an etching resist layer (16) and a back coat resin layer (17) in a predetermined shape on the metal foil (15), the metal foil (15) is formed in a predetermined shape. By etching, a large number of electrically independent conductor circuits (12) were formed.

Finally, as shown in FIG. 5(e), the etching resist layer (16) and back coat resin layer (17) are removed, and the surface of each conductor circuit (12) is plated as shown in FIG. 5(f). By forming the layer (18), a film carrier (100) as shown in FIG. 3 was obtained.

In the film carrier (10o) obtained in this way, just before mounting the electronic component (20), the frame body (13) and the reinforcing body (14) are attached at the two points in FIG. When it was removed by cutting along the chain line and the electronic component (20) was mounted as shown in FIG. 2, the inner lead (12a) was not bent.

Since there was no variation in plating thickness, the electronic component (20) could be mounted reliably.

(Effects of the Invention) As described above, in the film carrier according to the present invention, the frame body that connects these to each other is provided at the tips of the inner leads, so that when performing electrolytic plating, the tips of the inner leads can be easily attached. Since the concentrated current flows through the frame and no longer flows concentratedly through the tips of the inner leads, variations in plating thickness can be prevented.

In addition, by installing a reinforcing body integrally inside the frame, the strength of the frame itself is increased, and the frame and The inner lead connected to the frame does not bend, and by installing a reinforcing body instead of blocking the opening inside the frame, plating solution, cleaning solution, etc. When spraying, the frame and the inner lead connected to the frame are not bent by the spray pressure.

Therefore, it is possible to provide a film carrier on which electronic components can be reliably mounted.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a film carrier according to the present invention;
FIG. 2 is a cross-sectional view showing the state in which electronic components are mounted on the film carrier shown in FIG. 1, FIG. 3 is a partially enlarged plan view showing the inner lead portion of the film carrier shown in FIG. 1, and FIG. FIGS. 5(a) to 5(g) are cross-sectional views sequentially showing the method of mounting a film carrier according to the present invention, and FIG. 6 is a partially enlarged plan view showing the inner lead portion of another film carrier. 7UA is a plan view showing the film carrier of FIG. FIG. 8 is a partially enlarged plan view showing the inner lead portion of the film carrier in FIG. 6, and rpJ9 FIGS. Sectional views shown later, FIGS. 10 and 1
FIG. 1 is a partially enlarged plan view showing an inner lead portion of another conventional film carrier. Explanation of symbols 1 [1 (1...Film carrier, 10-...Film, 11...Device hole,'12...Conductor circuit,
12a...inner lead) (,12b...outer lead, 13...frame body, 14-...auxiliary bullet body,]5...
・Metal foil, 16-・etching resist layer. +7... Back coat resin layer, 18... Plating layer, 20-... Electronic component. that's all

Claims (1)

[Claims] A conductor circuit is formed on a film having a device hole for mounting an electronic component, one end of the conductor circuit is made to protrude toward the device hole, and this protruding portion is inserted into the device hole. A film carrier that serves as an inner lead for electrically connecting electronic components to be inserted, wherein a frame is provided at the tip of the inner lead to connect these to each other, and a frame is provided inside the frame integrally with the inner lead. A film carrier characterized by having a reinforcing body installed therein.