JP3221060B2 - Substrate processing method and manufacturing method of mounting substrate - 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 for treating a substrate and a method for treating the same.
The present invention relates to a method for manufacturing a mounting board using the same . INDUSTRIAL APPLICABILITY The present invention can be used as a method for processing various substrates such as an electronic circuit substrate and a method for manufacturing the same . For example, as a substrate process having a process for performing wire bonding on a printed circuit board or a process for mounting an IC chip by soldering, or manufacturing a mounting board requiring such a process.
It can be used as a fabrication method .

[0002]

2. Description of the Related Art When performing wire bonding on a substrate, gold plating is required on the substrate.
Further, TAB (Tape Antomated Bonding) or flip chip ( face-down bonding of an IC chip on a substrate ) requires soldering. For example, as shown in FIG. 3, a Cu foil 2 is printed on a substrate 1, and an IC
When the chip 4 is soldered, the Cu foil 2
Requires a soldering process for forming the preliminary solder 3 in advance.

[0003] However, such various processes are not always easy in the present day when the pattern on the substrate 1 is miniaturized. In particular, when the pattern gap L (distance between patterns) is less than 1 mm (see FIG. 3), such processing is difficult.

On the other hand, only one type of processing can be performed on the same substrate. For example, it is possible to perform only one of the metal processing of the gold plating processing and the solder processing. For this reason, even if wire bonding (gold plating is required) and flip chip mounting (solder processing is required) are both performed on the same substrate, the two types of metal processing cannot be performed, and both cannot be performed. This problem is a bottleneck for realizing high-density mounting.

[0005] Further, since the pattern for the flip chip has become so fine as to have a gap of 75 μm and a width of 75 μm, for example, the processing on the substrate is not easy as described above. It bridges with dips. As soldering, a technique called super solder soldering, which can perform fine processing, has been developed. However, even when such processing is performed, it is not always easy if the pattern is fine, Typically, more than one treatment cannot be performed on the substrate.

[0006] In addition, heat treatment (heat-resistant pre-flux treatment) of printed metal such as Cu foil may be required as another treatment. The same can be said for such treatment.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a substrate processing method capable of performing a plurality of processes on a substrate and a method of manufacturing a mounting substrate using the same. And

[0008]

Means for Solving the Problems The invention of each claim of the present application achieves the above object by adopting the following constitution.

[0009] The invention according to claim 1 of the present application is a method for manufacturing a semiconductor device on a substrate to be processed.
In the substrate surface treatment method of performing a plurality of types of treatment,
Treated with a photosensitive composition that can be developed and removed by light irradiation
Covering the main part of the surface, and in the first processing step, the photosensitive
Exposing a first surface to be treated to the composition;
And then in a second processing step, the same photosensitive composition
Exposing a second surface to be processed to an object;
A second process different from the first and second processes
Are gold plating, soldering, and heat treatment, respectively.
Any one of the substrate surface treatment methods,
The above object is achieved.

[0010] The invention according to claim 2 of the present application is characterized in that:
The plate has a pattern, with a gap of less than 1 mm
Or a pattern having a pattern width of less than 1 mm is formed.
The substrate surface treatment method according to claim 1, wherein
This achieves the above object.

[0011] The invention according to claim 3 of the present application is characterized in that
3. The board according to claim 1, wherein the board is a printed circuit board.
Substrate surface treatment method, thereby achieving the above object.
Is what it does.

[0012]

According to the present invention, the photosensitive composition formed on the entire surface can be removed from the required surface to be processed in each required processing step, and that portion can be exposed to carry out each processing. Thus, a plurality of substrate treatments and a plurality of metal treatments are possible according to the present invention.

[0013]

Next, embodiments of the present invention will be described with reference to the drawings. However, needless to say, the present invention is not limited by the following examples.

[0014] Example 1 This example, a Cu foil on the printed circuit board, and gold plating, the case where have rows both metal processing soldering by super solder printing, thereby obtaining a mounting substrate, the present invention Is applied.

In this embodiment, the substrate is prepared by the following procedures (A) to (F).

(A) A resist 5 of this type is formed on the entire surface of the substrate 1 as a photosensitive composition that can be developed and removed by light irradiation. Open resist. This is the first
This is a step of exposing the surface to be processed in which the processing step (here, the gold plating processing step) is performed. This results in the state shown in FIG. In FIG. 1, reference numerals 21 and 22 denote Cu foils.
The foil 21 and the Cu foil 22 should be subjected to different treatments (that is, gold plating and soldering). That is, in this step, the resist for the portion where the next second process (preliminary soldering process, especially super soldering process) is performed is left on the substrate 1 as it is. After the exposure and development, the substrate is transferred to the next plating step while the substrate remains dark (meaning that the exposure wavelength of the resist remains dark; the same applies hereinafter).

(B) Electroless gold plating is performed in a dark place.
This is the first processing step in this embodiment. Thus, as shown in FIG. 1B, the substrate 1 on which the first process 61 (gold plating process) has been performed is obtained. At this point, it is assumed that the resist 5 has not been cured (cured) yet.

(C) Next, the portion to be subjected to the soldering, which is the second process, is covered with a mask 8 as shown in FIG.
Exposure using. Exposure light is indicated by reference numeral 7.

(D) By developing, as shown in FIG.
As shown in (2), a portion of the Cu foil 22 where solder processing as the second processing is to be performed is exposed.

(E) Next, a solder material is applied and heat-treated to form a solder only on the surface of the necessary part. For example, a so-called super solder is solid-printed on a portion to be soldered. Super solder printing is advantageous because solder can be applied uniformly. FIG. 1
The structure shown in FIG.

(F) Next, by heat-treating the super solder, the solder 63 remains only in the portion of the Cu foil 22,
There is no bridge, and the same processing as solder plating can be performed.

FIG. 2 shows a plane of the substrate 1 to be processed obtained as described above. Only necessary portions are subjected to a gold plating process as a first process 61, and only necessary portions are formed with solders 63 obtained by the second process. Other portions are still covered with the resist 5 in this state.

Further, when another processing such as heat-resistant pre-flux processing is desired to be performed on other Cu foil portions, the required portions are exposed and developed by irradiating light, a resist opening is provided, a processing portion is applied, and further heating is performed. By doing so, the processing can be performed.

The pattern formed by the Cu foils 21 and 22 of this embodiment has a pattern gap and a pattern width of 1 respectively.
Although it is less than 1 mm (especially a gap of 75 μm and a width of 75 μm) and the processing is difficult, a plurality of metal treatments can be performed according to the present embodiment, and the processing can be achieved satisfactorily.

As described above, according to the present embodiment, gold plating and soldering can be performed on the same substrate by performing two-step exposure when preparing the preliminary solder (solder resist) for the substrate. Further, a heat-resistant pre-flux treatment in which a heat-resistant treatment is performed on the copper foil in advance for a reflow treatment in the next step is also possible, and three types of substrate treatments are also possible. These are made possible by using two-step exposure (or multi-step exposure) of the resist.

[0026]

According to the present invention, there is provided a substrate processing method and a method for manufacturing a mounting substrate.
According to the manufacturing method , there is an effect that a plurality of processes can be performed on the substrate.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the steps of Example 1 in order.

FIG. 2 is a plan view of a substrate to be processed according to the first embodiment.

FIG. 3 is a diagram showing a conventional technique.

[Explanation of symbols]

 Reference Signs List 1 substrate 21, 22 Cu foil (pattern) 61 First treatment (gold plating treatment) 62 Second treatment (super solder printing solder treatment) 63 Solder (obtained by second treatment)

Claims (3)

(57) [Claims] 1. A substrate surface treatment method for performing a plurality of types of treatments on a substrate to be treated, wherein a first portion of the surface to be treated is covered with a photosensitive composition which can be developed and removed by light irradiation. In the step, a first processing surface is exposed to the photosensitive composition, a first processing is performed, and then, in a second processing step, the same photosensitive composition is exposed.
Exposes the second surface to be processed, and is different from the first process.
A second process is performed, and the first and second processes are each performed by a gold plating process.
A substrate surface treatment method that is one of the following : 2. The processing target substrate has a gap of less than 1 mm.
Pattern with loop or pattern width less than 1mm
The substrate surface treatment method according to claim 1, wherein a pattern having : 3. The substrate to be processed is a printed circuit board.
The substrate surface treatment method according to claim 1 or 2 that.