JPH09118963A - Base stock for fine etching work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base stock for fine etching work with which fine etching work is quickly and accurately executed and also the generation of surface ruggedness is prevented, defective etching caused by nonmetallic inclusion is not observed and high-quality etched products are manufactured. SOLUTION: The base stock for fine etching work is a base stock of a nickel- iron alloy for etching work consisting of a 42% Ni-Fe alloy or a 36% Ni-Fe alloy of 0.020-0.40mm thick which is manufactured by cold rolling, the content of C in the base stock is <=0.01% and the cross-sectional cleanliness that is specified by JIS G 0555 is <=0.017%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for fine etching, and more particularly to a material for fine etching such as a high-definition shadow mask.

[0002]

2. Description of the Related Art Most lead frames for ICs have a thickness of 0.
42% nickel-iron alloy called 42 alloy of 10 to 0.30 mm is manufactured by press punching or etching. Conventionally, aluminum killed steel has been used for the shadow mask for color cathode ray tubes, but it is amber material with a small coefficient of thermal expansion (30% nickel-
Iron alloys) have also come to be used. In addition, 50% nickel-iron alloy is used as a material for various electronic parts such as display tubes.

The products manufactured by such etching process have a large dimensional accuracy allowable range, and the linearity and roundness of the shape formed by the etching process are not so severe, and the conventional technology can sufficiently cope with them. It was However, the lead frame 100 ~
There are some technical problems with respect to a multi-pin product such as 160 pins and a finely processed product such as a high-definition mask having a pitch of 0.2 to 0.3 mm in a shadow mask.

First, when a lead frame with a fine pitch, a shadow mask, and other electronic parts are processed by etching, the etching time becomes long, so the adhesion between the photoresist and the material is reduced, and the processing of products formed by etching is processed. There was a problem that the linearity and roundness of the part were damaged.

Secondly, there is a problem in that the cross section formed by etching becomes a state called arabic, which causes rasping. Such arabis, for example, subtly affects unevenness in a shadow mask, resulting in deterioration of the quality of the entire mask.

Thirdly, inclusions of a size which was not a problem in practice in a lead frame having a small number of pins or a consumer shadow mask become a problem in a lead frame having a large number of pins and a high-definition shadow mask, resulting in a yield in the etching process. There was a problem of lowering.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention is directed to solving the above-mentioned conventional drawbacks.
A material for fine etching processing that enables faster and more accurate fine etching processing, prevents the occurrence of arabic, does not show etching defects due to non-metallic inclusions, and can manufacture high-quality etching products. It is intended to be provided.

[0008]

As a result of research to solve the above problems, the present inventor found that the carbon content in the material was 0.0
It has been found that the desired object can be achieved by controlling the cross-sectional cleanliness degree to be 1% or less and JIS G 0555 to 0.007% or less, and the present invention has been completed based on such findings. Is.

That is, the gist of the present invention is 42% Ni-F having a plate thickness of 0.020 to 0.40 mm produced by cold rolling.
In a nickel-iron alloy material for etching, which comprises an e alloy or a 36% Ni-Fe alloy, the carbon content of the material is 0.01% or less, and JIS G 0
It is a material for fine etching processing characterized by a cross-sectional cleanliness degree defined by 555 of 0.017% or less.

Here, 42% Ni-Fe alloy, 36% N
The i-Fe alloy is, for example, a Military Standard (MI
LI-23011C (March 29, 1974) "IRON
-NICKEL ALLOYS FOR SEALING TO GLASSES AND CERAMIC
S "(see Table II Class 5 and Class 7)) means the well-known so-called 42% alloy, 36% alloy, specifically containing about 42% Ni, or 36%.
By Ni-Fe alloy containing some Ni.

[0011]

The carbon content in the present invention is 0.01%.
By the following, the etching rate is accelerated and arabic is eliminated.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The etching rate of a nickel-iron alloy depends on the nickel content, and the lower the nickel content, the faster the etching rate.
As a result of investigating nickel-iron alloys of 0% or less, a common phenomenon that a plurality of nickel-iron alloys having different nickel contents have a high etching rate when the carbon content is 0.01% or less was observed.

FIG. 1 shows the change in etching rate with carbon content determined for a 42% nickel-iron alloy.

As is apparent from this figure, when the etching rate is 1 when the carbon content is 0.02%, it is 0.0
1.25 to 1.30 when the carbon content is 1% or less, and 25% to 30% as compared with the case where the carbon content is 0.02%.
Be faster.

FIG. 2 also shows the change in etching rate depending on the carbon content obtained for the 36% nickel-iron alloy. Similarly, in the case of the 36% nickel-iron alloy and the case of the 42% nickel-iron alloy, the etching rate becomes high when the carbon content is 0.01% or less.

Further, by setting the carbon content to 0.01% or less, defects due to carbide inclusions are substantially eliminated.

Table 1 shows the relationship between the carbon content and the defect rate due to carbide inclusions in a 0.3 mm pitch high definition shadow mask. Table 1 Carbon content (%) Defect rate of shadow mask due to carbide inclusions 0.05 0.1 to 1.0% 0.02 0 to 0.5% 0.01 0% 0.0050 0% From this table As is apparent, when the carbon content is 0.01% or less, the defective rate due to the carbide inclusions is 0%.

Next, in the present invention, JIS G 0555 is used.
By setting the cross-sectional cleanliness degree defined by the above to 0.007% or less, the number of non-metallic inclusions in the material is increased to the extent that the presence of non-metallic inclusions in the material does not substantially hinder fine processing. It can be reduced.

In the iron-nickel alloy, when the carbon content is 0.01% or less, the non-metallic inclusions in the material are mainly oxides of elements such as Al, Si and Ca.
Among these oxides, those having a size of 10 μm or more pose a problem in microfabrication.

Table 2 shows the cross-sectional cleanliness of non-metallic inclusions specified in JIS G 0555 and the number of non-metallic inclusions having a size of 10 μm or more (number per 10 mm × 10 mm).
The relationship is shown below. No. 2 number of non-metallic inclusions with cross section cleanliness of 10 μm (10 mm x 10 mm) 0.004% 0 to 1 0.008% 0 to 3 0.013% 0 to 5 0.017% 0 to 10 0.021% 2 to 20 0.058% 10 to 50 2nd As is clear from the table, when the cross-section cleanliness is 0.017% or less, 10 μm per unit area of 10 mm × 10 mm
The number of non-metallic inclusions described above can be reduced to less than three. With such a degree of cross-section cleanliness, the presence of non-metallic inclusions does not substantially hinder fine processing.

It should be noted that the Ni-Fe alloy having a Ni content of 42% has a thermal expansion coefficient close to that of ceramics, silicon, etc., and has been conventionally suitably used as an IC lead frame material or the like. It is a material. Further, a Ni content of 36% has a remarkably small thermal expansion coefficient and is known as an amber material,
In recent years, it is a material that has come to be used as a shadow mask material or the like by taking advantage of its thermal expansion coefficient and corrosion resistance.

[0022]

EXAMPLE 1 Ni% with a plate thickness of 0.13 mm; 35.7%, C%; 0.00
4% and a large number of large circle dot-shaped openings (diameter 0.150 mm) arranged at a 0.25 mm pitch on one surface of a material made of a nickel-iron alloy having a cross section cleanliness of 0.004% according to JIS G 0555. ) Is provided, and a second resist pattern having a large number of small circular dot-shaped openings (diameter 0.090 mm) arranged at a pitch of 0.25 mm is provided on the other surface. 46 ° B
Using e'FeCl ₃ etchant, spray etching from both sides with a spray pressure of 2.0 kg / cm ² to etch a large number of holes with a diameter of 0.220 mm for large holes and 0.110 mm for small holes. , Got the product. Reference Example 1 Ni% of plate thickness 0.15 mm; 41.5%, C%; 0.00
7%, cross section cleanliness according to JIS G 0555 is 0.0
160% on both sides of the material consisting of 08% nickel-iron alloy
Provide a resist pattern for the lead frame of the pin, and use a 48 ° Be'FeCl ₃ corrosive liquid at a liquid temperature of 70 ° C. for 2.0
A product was obtained by spray etching from both sides with a spray pressure of kg / cm ² . Comparative Example 1 Ni% with a plate thickness of 0.13 mm; 35.5%, C%; 0.02
A resist plate was made in the same manner as in Example 1 on a material made of a nickel-iron alloy having a cross-sectional cleanliness degree of 0.033% according to JIS G 0555 of 2% and then a liquid temperature of 60.
2.0 kg / using 46 ° Be'FeCl ₃ corrosive liquid at ℃
Spray etching was performed from both sides with a spray pressure of cm ² , and a large number of apertures having a diameter of 0.220 mm for the large holes and 0.110 mm for the small holes were etched to obtain a product. Comparative Example 2 Ni% having a plate thickness of 0.15 mm; 41.8%, C%; 0.02
3%, cross section cleanliness according to JIS G 0555 is 0.0
A resist plate-making process was performed on a material composed of a nickel-iron alloy of 50% in the same manner as in Example 2, and then the liquid temperature was changed to 4 at a temperature of 70 ° C.
A product was obtained by spray etching from both sides with a spray pressure of 2.0 kg / cm ² using an 8 ° Be′FeCl ₃ etching solution.

Table 3 shows the results of Examples 1 and 2 and Comparative Examples 1 and 2. Table 3 Ni% C% Cross-section cleanliness Etching Etching defect rate % Status status Example 1 35.7 0.004 0.004 1.28 Good 0% Comparative example 1 35.5 0.022 0.033 1.00 With arabic 0.5% Reference example 1 41.5 0.007 0.008 1.25 Good 0% Comparative example 2 41.8 0.023 0.050 1.0 With arabic 1.3% (Note) Etching rate contains carbon The rate at which a predetermined size is reached when a material having an amount of 0.023% is etched is defined as 1.

As shown in Table 3, the product according to the present invention can be finely etched in a quicker and more accurate manner than the conventional nickel-iron alloy, and the product has no arabic. In addition, no etching failure due to non-metallic inclusions was observed.

[0025]

As described above in detail, according to the material of the present invention, fine etching processing can be performed quickly and accurately,
It is possible to manufacture a high-quality etching product, since no arabi is observed and no etching failure due to non-metallic inclusions is observed.

[Brief description of the drawings]

FIG. 1 is a graph showing a change in etching rate depending on the amount of carbon obtained for a 42% Ni—Fe alloy.

FIG. 2 is a graph showing a change in etching rate depending on the amount of carbon obtained for a 36% Ni—Fe alloy.

Claims (1)

[Claims] 1. A plate thickness of 0.02 produced by cold rolling.
0% to 0.40 mm 42% Ni-Fe alloy or 36% N
In a nickel-iron alloy material for etching processing made of an i-Fe alloy, the carbon content in the material is 0.01%.
A material for fine etching processing, which is the following and has a cross-sectional cleanliness degree of 0.017% or less defined by JIS G0555.