JP2705566B2 - Method for manufacturing semiconductor integrated circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor integrated circuit device, and more particularly to a method of manufacturing a semiconductor integrated circuit device in which a semiconductor bare chip and a surface mount component are mounted in a mixed state on the same substrate.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a semiconductor integrated circuit device in which a COB structure in which a semiconductor bare chip is mounted on a substrate and an SMT structure in which surface mounting components such as chip resistors and chip capacitors are mounted on the substrate, are mixed. Especially for COB structures that need to ensure electrical reliability, SMT
Care must be taken to ensure that the implementation of the structure does not have any adverse effects.

[0003] In this case, there is a difference particularly in the soldering process depending on whether the COB process or the SMT process is performed first. For example, when the COB process is performed first, after the COB process in which the semiconductor bare chip is mounted on the substrate, the circuit portion of the substrate is so formed that the temperature of the COB structure is not adversely affected by solder or the like when the SMT is mounted. Solder is applied to the SMT area using a dispenser, and thereafter, the SMT process is performed by mounting a surface mount component.

Alternatively, after the COB process, solder is printed only in the SMT region using a specially shaped solder mask, and thereafter, the SMT process is performed by mounting surface mount components. Japanese Patent Application Laid-Open No. 61-97 discloses an example of such a manufacturing method.
No. 893. In the method of this publication, a mask provided with a window in a portion corresponding to the previously mounted COB and a portion to be printed with solder is used.
Solder printing is performed in a state where a portion corresponding to OB is covered with a flexible film. Thus, SMT can be performed without impairing the reliability of the COB.

On the other hand, when the SMT process is performed first, a high-efficiency reflow method can be adopted for mounting the surface mount components, and the COB structure is not affected at this time. Since the COB structure area is contaminated, the COB structure area is cleaned and then the COB structure area is cleaned.
Step B is performed.

[0006]

However, in the solder application method using a dispenser, it is difficult to uniformly control the amount of solder to be applied. There is a problem in that it flows together with the solder, and if the amount of solder is small, reliable mounting cannot be performed. Further, in a printing method using a solder mask as described in the above-mentioned publication, a process of opening a window corresponding to a large number of fine chip components and manufacturing a mask becomes extremely complicated, and a mask for a substrate is also required. There is a problem that high precision is required for the alignment of the semiconductor integrated circuit, and it is difficult to manufacture a semiconductor integrated circuit device mounted at high density.

In the step of performing SMT first, COB
Although the influence on the structure can be avoided, there is a problem that a step of cleaning the COB mounting area is required, and the management of the cleaning is complicated and a complicated step is required.

[0008]

OBJECTS OF THE INVENTION It is an object of the present invention to provide an
An object of the present invention is to provide a method of manufacturing a semiconductor integrated circuit device in which the influence of the MT process is avoided and the reliability of the COB structure is improved.
Another object of the present invention is to provide a manufacturing method which simplifies the SMT process, and particularly enables the formation of the solder layer and the simplification of the soldering process. It is a further object of the present invention to provide a manufacturing method in which the cleaning of the COB mounting area is not required and the manufacturing is facilitated and the manufacturing efficiency is improved.

[0009]

A manufacturing method according to the present invention comprises a step of printing solder on a substrate, a step of mounting an SMT component on the substrate, and a step of mounting a protective frame in the COB mounting area. Coating step and S by a reflow method.
It includes a step of soldering the MT component and a step of removing the protective frame to expose the substrate surface and mounting the COB component on the exposed surface.

The manufacturing method of the present invention comprises the steps of printing solder on a substrate, mounting an SMT component on the substrate, and
A step of mounting a protective frame in the OB mounting area to cover the substrate surface in the COB mounting area, a step of soldering the SMT components by the reflow method, and a step of removing a part of the protective frame and placing the substrate surface inside the protective frame. And a step of mounting the COB component on the exposed surface, and a step of filling the protective frame with resin and sealing the COB component with resin.

Here, the protective frame is composed of a frame surrounding the COB mounting area, a heat-resistant sheet covering the upper surface of the frame, and an adhesive tape for bonding the frame to the surface of the substrate.
At the time of soldering the T component, a method is used in which the COB mounting region is covered with a heat-resistant sheet, and after mounting the SMT component, the heat-resistant sheet is peeled off to expose the COB mounting region.
Further, the resin for resin sealing is dropped into the frame of the protective frame to a height covering the COB component to perform resin sealing.

[0012]

According to the manufacturing method of the present invention, the SMT mounting step is performed in a state where the COB mounting area is protected by the protection frame. Therefore, except for mounting the protection frame, the SMT mounting step can be easily performed similarly to the conventional SMT mounting step. And, during this SMT mounting process, CO
Since the B mounting area is held by the protective frame, the contamination is prevented and the cleaning step is not required.

In the manufacturing method of the present invention, in the resin sealing step for sealing the COB structure, since the outer shape of the sealing resin is restricted by the protective frame, the resin flows to the surrounding SMT mounting area. The external dimensions and the height of the sealing resin can be managed with high accuracy without any need for the sealing resin, and a highly reliable sealing structure can be obtained.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of the manufacturing method of the present invention in the order of steps. First, as shown in FIG. 1A, a circuit board 11 in which a required conductive film pattern is formed on the surface of an organic insulating substrate and is covered with an insulating coating except for parts where COB and SMT components are mounted. Perform solder printing. In this solder printing, for example, a solder sheet 12 having a solder paste film is placed on the circuit board 11 and a head 13 is pressed against the circuit board 11 from above, so that the solder paste is applied to the surface of the circuit board 11 in a required pattern. Can be adopted. Then, as shown in FIG.
The T component 14 is mounted at a required position on the surface of the circuit board 11. At this time, the protection frame 15 is mounted on the COB mounting area on the circuit board 11.

As shown in perspective and sectional views in FIGS. 2 and 3, the protective frame 15 has a vertical and horizontal dimension including a semiconductor bare chip to be mounted and a bonding area disposed around the semiconductor bare chip. The frame 151 includes a rectangular frame 151 having a dimension higher than the maximum height, a heat-resistant sheet 152 stretched over the upper surface of the frame 151, and a double-sided tape 153 attached to the lower surface of the frame 151. ,
The double-sided tape 153 is bonded and fixed on the surface of the circuit board 11.

Then, as shown in FIG. 1 (c), the circuit board 11 is passed through a reflow furnace 16, the printed solder is melted, and the SMT component 14 is soldered to the circuit board 11 for mounting. Next, as shown in FIG. 3D, the protection frame 15 is removed from the circuit board 11 to expose the COB mounting area of the circuit board 11 covered by the protection frame 15. And
As shown in (e), the semiconductor bare chip 17 is mounted on the COB mounting area. For this mounting, a conductive adhesive, a metal brazing material, or the like is used. Then, as shown in an enlarged view in FIG. 4, the mounted semiconductor bare chip 17 and the conductive film pattern of the circuit board 11 are electrically connected by bonding wires 18. Thereafter, a sealing resin 19 is dropped on the semiconductor bare chip 17, and the semiconductor bare chip 17 and the bonding wires 18 are sealed with the resin 19.

Therefore, in this manufacturing method, the SM
T mounting is performed. In this case, solder printing is first performed on the entire surface of the circuit board 11, the protective frame 15 and the SMT component 14 are mounted, and then each step of solder reflow may be performed. Except for mounting the frame 15, the same process as the conventional SMT mounting process may be used. And during this SMT mounting process,
Since the COB mounting area of the circuit board 11 is kept in a sealed state by the protective frame 15, this area is not contaminated. Therefore, after that, the protection frame 15 is attached to the circuit board 11.
When the circuit board 11 is detached from above, the clean COB mounting area is exposed on the circuit board 11, and the cleaning step is not required.

Therefore, the conventional COB mounting process can be directly performed on the COB mounting area. Since the SMT mounting step has already been completed before the COB mounting step, the COB structure is not damaged.

FIG. 5 is a view showing a second embodiment of the present invention in the order of steps. It should be noted that the steps of FIGS.
This is the same as the embodiment. That is, as shown in FIG. 2A, a required conductive film pattern is formed on an organic insulating substrate and
Solder printing is performed on the circuit board 11 covered with the insulating coating except for the parts where the components B and SMT are mounted. Then, as shown in FIG. 3B, the SMT component 14 is mounted at a required position on the substrate. At this time, the protection frame 15 is mounted on the COB mounting area on the surface of the circuit board 11. This protection frame 15 is the same as that shown in the first embodiment,
1 is adhered and fixed on the surface of the circuit board 11 by the double-sided tape 153 attached to the lower surface of the circuit board 11.

Then, as shown in FIG. 1C, the circuit board 11 is passed through a reflow furnace 16, the printed solder is melted, and the SMT component 14 is soldered to the circuit board 11 for mounting. Next, as shown in FIG. 3D, the heat-resistant sheet 152 of the protection frame 15 fixed to the COB mounting area is peeled off from the frame 151, and the COB mounting area of the circuit board 11 covered with the heat-resistant sheet 152 is removed. It is exposed inside the frame 151. Then, the semiconductor bare chip 17 is mounted on the circuit board 11 in the COB mounting area surrounded by the frame 151.
For this mounting, a conductive adhesive, a metal brazing material, or the like is used. Then, as shown in FIG. 6, the mounted semiconductor bare chip 17 and the circuit on the substrate are electrically connected by bonding wires 18.

Thereafter, the sealing resin 1 is placed in the frame 151.
9 is dropped, and the mounted semiconductor bare chip 17 and bonding wire 18 are sealed with resin 19. At this time,
The frame 151 restrains the outer shape of the sealing resin 19 and prevents the resin 19 from flowing out to the surroundings. After the sealing resin 19 is cured, the COB structure is completed by removing the frame 151 from the substrate.

Also in the second embodiment, the SMT mounting is performed first. In this case, solder printing is performed on the entire surface of the circuit board 11, the protection frame 15 and the SMT components 14 are mounted, and thereafter, Since it is sufficient to perform each step of solder reflow,
Except for mounting the protection frame 15, the same process as the conventional SMT mounting process may be used. During the SMT mounting step, the COB mounting area of the circuit board 11 is kept in a sealed state by the protection frame 15, so that this area is not contaminated. Therefore, after that, the heat-resistant sheet 15
When 2 is peeled off, a clean COB mounting area is exposed in the frame 151, and the cleaning step is not required.

Therefore, the conventional COB mounting process can be directly performed on the COB mounting area. Since the SMT mounting step has already been completed before the COB mounting step, the COB structure is not damaged.

Further, in the second embodiment, in the resin sealing step for sealing the COB structure, the flow of the sealing resin 19 is restricted by the frame 151, so that the resin may be applied even if the potting method is adopted. The external dimensions and the height of the sealing resin 19 can be managed with high precision without the 19 flowing to the surrounding SMT mounting area, and highly reliable sealing can be realized. The frame 151 may be left on the circuit board 11 as a part of the COB structure. Or,
It may be subsequently removed as described above.

Although each of the above embodiments shows an example in which a semiconductor bare chip is mounted on a substrate by a wire bonding method, the present invention can be applied to a case where the semiconductor bare chip is mounted by a face down bonding method.

[0026]

As described above, according to the present invention, the SM
T-mounting is performed. In this case, solder printing is performed on the entire surface of the board, a protective frame and SMT components are mounted, and then each step of solder reflow is performed. May be the same as the conventional SMT mounting process.
The MT mounting process can be easily performed. Also, this S
During the MT mounting process, the COB mounting area is held in a sealed state by the protective frame, so that this area is not contaminated, and the COB mounting area does not need to be cleaned, and the process can be simplified and simplified. And the manufacturing efficiency is improved.

Also, the conventional COB mounting process can be directly performed on the COB mounting region, and the SMT mounting process has already been completed before the COB mounting process. No damage.

Further, in the resin sealing step of the COB mounting step, since the outer shape of the sealing resin is constrained by the protective frame, the resin flows to the surrounding SMT mounting area even if the resin sealing is performed by a potting method or the like. The external dimensions and the height of the sealing resin can be managed with high precision, and a highly reliable sealing structure can be easily realized.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of the present invention in the order of steps.

FIG. 2 is a perspective view of a protection frame.

FIG. 3 is a sectional view of a protection frame.

FIG. 4 is an enlarged sectional view of a COB portion of the first embodiment.

FIG. 5 is a front view showing a second embodiment of the present invention in the order of steps.

FIG. 6 is an enlarged sectional view of a COB portion according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Circuit board 12 Solder sheet 14 SMT component 15 Protective frame 16 Reflow furnace 17 Semiconductor bare chip 18 Bonding wire 19 Sealing resin 151 Frame body 152 Heat-resistant sheet 153 Double-sided tape

Claims (4)

(57) [Claims] A step of printing solder on a substrate when manufacturing a semiconductor integrated circuit device in which a semiconductor bare chip and a surface mounting component are mounted on the same substrate; and mounting the surface mounting component on the substrate and the semiconductor bare chip. Mounting a protective frame on the area where the substrate is mounted and covering the substrate surface in the semiconductor bare chip mounting area, soldering the surface mounted component by a reflow method, and removing the protective frame to remove the substrate surface. Exposing and mounting a semiconductor bare chip on the exposed surface. 2. A process for printing a solder on a substrate when manufacturing a semiconductor integrated circuit device in which a semiconductor bare chip and a surface-mounted component are mounted on the same substrate; and mounting the surface-mounted component on the substrate and the semiconductor bare chip. Mounting a protective frame on the area where the semiconductor chip is mounted, covering the surface of the substrate in the semiconductor bare chip mounting area, soldering the surface mounted component by a reflow method, and removing a part of the protective frame for protection. Exposing the surface of the substrate inside a frame, mounting a semiconductor bare chip on the exposed surface, and filling the protective frame with a resin and sealing the front semiconductor bare chip with a resin. A method for manufacturing a semiconductor integrated circuit device. 3. The protection frame includes a frame surrounding a mounting region of the semiconductor bare chip, a heat-resistant sheet covering an upper surface of the frame, and an adhesive tape for bonding the frame to a substrate surface. 3. The method for manufacturing a semiconductor integrated circuit device according to claim 2, wherein the heat-resistant sheet covers the mounting area of the semiconductor bare chip at the time of soldering, and after mounting the surface-mounted components, peels off the heat-resistant sheet to expose the semiconductor bare chip mounting area. 4. The method of manufacturing a semiconductor integrated circuit device according to claim 2, wherein the resin for resin encapsulation is dropped into the frame of the protective frame to a height covering the semiconductor bare chip.