JPH10306349A - Low thermal expansion alloy sheet for electronic parts, excellent in etching characteristic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low thermal expansion alloy sheet for electronic parts, free from the occurrence of inferior etching, such as striped irregularity, causing deterioration in the local visibility of image. SOLUTION: This alloy sheet is composed of an Fe-Ni alloy containing, by mass, 32-38% Ni or an Fe-Ni-Co alloy containing, by mass, 23-38% Ni and <=7% Co and satisfying Ni+Co=32 to 38%. Moreover, the amount of concentration fluctuations of Ni microsegregation with respect to the direction orthogonal to rolling direction in the plane to be subjected to etching is <=2 mass% and also the width of the concentration fluctuation zone of Ni microsegregation is >=500 μm, or further, the proportion (%) of degree of orientation of the 100} crystal plane to the rolling surface is 20-40% or >=80%. The alloy sheet is used as a starting sheet for a product in which a pit pitch by eyching is regulated to <=300 μm. By this method, etching velocity at the time of etching can be uniformized, and the occurrence of striped irregularity can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-thermal-expansion alloy thin plate used in an electronic section for performing fine etching such as a shadow mask and a lead frame, and more particularly to a high-definition shadow mask used for a computer display. The present invention relates to a low-thermal-expansion alloy sheet having excellent etching properties.

[0002]

2. Description of the Related Art Electronic parts such as shadow masks and lead frames are generally used after being subjected to etching.
At this time, there is a demand for a material having a high etching rate and a high etching property which is excellent in the end shape and dimensional accuracy of the hole after etching.

Hereinafter, a shadow mask will be described as an example. Shadow masks are used in television cathode-ray tubes, and are used to provide a specific color tone by precisely irradiating an electron beam emitted from an electron gun to a predetermined position on a phosphor screen supported by a glass body. Has pores. In this case, about 20% of the emitted electron beams pass through the pores and irradiate the phosphor, and the remaining
Since 80% of the glass collides with the shadow mask, the temperature of the shadow mask becomes higher than that of the glass body supporting the phosphor screen. In addition, mild steel sheets such as low-carbon rimmed steel and low-carbon aluminum-killed steel that have been conventionally used as materials for shadow masks have a much larger coefficient of thermal expansion than the glass body that supports the phosphor screen, An electron beam cannot be accurately irradiated to a predetermined position on the phosphor screen due to a positional deviation between them, and the image often becomes unclear.

In order to prevent the image from becoming unclear, attempts have been made to compensate for the above-mentioned positional deviation by devising the structure of a support serving as a suspension device of the shadow mask, but it is not always sufficient. Absent. Further, in recent years, with the enlargement, higher quality, and higher luminance of the television screen, these positional shift problems have become more apparent.

Therefore, as a material for a shadow mask, 36
The use of Fe-Ni-based alloys containing mass% Ni is expanding. This alloy has a thermal expansion coefficient of about
Since it is as small as 1/10 and its low expansion property is maintained even when the electron beam is heated on a high luminance screen, a color shift due to thermal expansion hardly occurs in a shadow mask manufactured using this material as a material.

[0006] Fe-Ni-based alloy sheets for shadow masks are usually prepared by adjusting alloy slabs or steel ingots by continuous casting or ingot casting, and then subjected to slab rolling, hot rolling, cold rolling and annealing. Manufactured. After forming an electron beam passage hole in this alloy thin plate by photo etching, annealing,
A shadow mask is manufactured by performing various processes such as molding and blackening.

[0007] However, a shadow mask made of an Fe-Ni alloy thin plate has excellent low thermal expansion characteristics,
Because of poor etching properties, it is difficult to obtain a good hole shape by photo-etching, and poor etching may cause local poor image sharpness. Therefore, attempts have been made to improve the etching properties of this alloy sheet.

For example, in Japanese Patent Publication No. 59-32859, in order to make the hole shape after photoetching uniform over the entire shadow mask, it is necessary to keep the etching rate constant while preventing the crystal orientation of the etching surface from being irregular. In view of the above, improvement is achieved by setting the orientation ratio of the {100} crystal plane to 35% or more.

[0009]

However, in recent years,
With the enlargement of television screens and the expansion of applications to computer displays, the demand for finer images and higher brightness has been increasing, and as a result, holes for passing electron beams must be drilled with higher precision. Etching processing is required.

In particular, a high-definition shadow mask used for a computer display mainly has a thickness of 0.15 mm.
The following materials are used, for example, a hole with a diameter of 120 μm is 270
The holes are drilled at a pitch of μm, and attempts have been made to make the pitch even finer.

[0011] In order to accurately drill such fine holes in the etching image, the material of the raw material has been improved together with the improvement of the etching technique, but the hole shape caused by the local etching defect still remains. Has occurred, which is one of the causes of the local poor definition of the image.

[0012] This etching defect is observed as fine linear unevenness in the mask portion along the rolling direction of the alloy thin plate, and is called "line unevenness". Figure 3 shows Fe-36mas
FIG. 4 is a schematic view showing a state in which streak unevenness occurs on a shadow mask made of a s% Ni alloy thin plate. Most of the line unevenness has a width of several tens μm to several mm, and reaches one side to the other side of the mask portion as shown in FIG.

Until now, it has been known that unevenness of stripes occurs during etching due to segregation of Ni or segregation of impurities, and several techniques have been proposed for suppressing unevenness of stripes.

For example, Japanese Patent Application Laid-Open No. Sho 61-223188 discloses that the unevenness of stripes is caused by the segregation of Ni. It discloses a technology to reduce the length to 300 mm or less.

In Japanese Patent Publication No. 63-64514, it is assumed that the unevenness of the stripes is caused by the enrichment of Ni. %
In the following, and by setting the length to 30 mm or less, streak unevenness is suppressed.

However, Fe-N containing 32 to 38 mass% of Ni
In the i-type alloy sheet, there is no region where Ni is concentrated more than 10% with respect to the average concentration.On the other hand, even if the concentration is several%, etching defects such as uneven stripes may occur. Has been confirmed.

In Japanese Patent Application Laid-Open No. 2-54744, streak unevenness is assumed to be caused by segregation of impurity elements such as C, Si, Mn and Cr, or by a solidification structure at the time of casting.
By adding mass% B and heating the slab under specific conditions, segregation is prevented, columnar crystal structure is reduced, and streak unevenness is suppressed. However, for materials that require fine etching and low thermal expansion, such as shadow mask materials, C, S
Elements such as i, Mn, and Cr are reduced as much as possible to less than 1 mass% in total, and streak unevenness due to such segregation cannot occur, and streak unevenness generated in Fe-36 mass% Ni alloy thin plate Does not eliminate the problem. On the other hand, in the blackening process of the shadow mask, if B exceeds 0.02 mass%, uneven blackening occurs and local color shift occurs.

As described above, even if any of the above techniques is used, it is impossible to overcome the streak unevenness due to the etching process that occurs in the Fe-36mass% Ni alloy thin plate. Therefore, etching defects such as uneven stripes tend to increase, and a countermeasure is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and does not cause etching defects such as uneven stripes which cause a local decrease in the sharpness of an image, and an electronic device capable of performing high-precision etching. An object of the present invention is to provide a low thermal expansion alloy sheet for a part.

[0020]

The present inventors have conducted various studies on the etching properties of Fe-Ni-based low thermal expansion alloy thin plates. It has been found that the occurrence occurs either due to the amount of concentration fluctuation of microsegregation and the width of the concentration fluctuation part of Ni microsegregation, or in combination with the orientation ratio of {100} crystal plane to the rolling surface.

The micro-segregation of Ni is performed by analyzing the amount of fluctuation of the concentration of the Ni component and the width of the concentration fluctuation portion on the surface or cross section in the direction perpendicular to the rolling direction in the plane of the product original plate to be etched. Specifically, the surface or cross section of the product original plate in the direction perpendicular to the rolling direction was Ni-
The concentration of the component is analyzed to obtain a Ni concentration distribution curve.

The Ni concentration fluctuation amount Ni _D (%) is calculated from the maximum Ni concentration Ni _max (%) and the minimum Ni concentration Ni _min (%) in the Ni concentration distribution curve.
From the difference between In the Ni concentration distribution curve, the average
When the Ni concentration is Ni _AV (%) and there are n Ni segregation portions exceeding the average Ni concentration Ni _AV (%), and the width of the i-th Ni segregation portion is S _i , the width S ( μm) is obtained from S (μm) = ΣS _i / n.

FIG. 2 shows an example of the result of analyzing the concentration of Ni component on the surface in the direction perpendicular to the rolling direction of the Fe-36mass% Ni alloy thin plate using an electron beam microanalyzer. In the case of FIG.
There are seven Ni segregation sites exceeding the average Ni concentration Ni _AV (%),
The concentration fluctuation amount Ni _D (%) and the width S (μm) of the Ni concentration fluctuation part are as follows:
Ni _D (%) = Ni _max (%)-Ni _min (%), S (μm) = Σ
(S _I + S ₂ +… + S ₇ ) / 7

In the etched surface of the original product plate, FIG.
If there is a fluctuation in the concentration of Ni as shown in (a) and (b), etching defects such as uneven stripes are likely to occur due to a relative difference in etching rate depending on the concentration difference. In particular, when the density fluctuation amount is large and the width of the density fluctuation portion is large, the stripe unevenness becomes remarkable.

Further, in addition to reducing the amount of concentration fluctuation of Ni microsegregation and the width of the concentration fluctuation portion, the degree of orientation of the crystal plane with respect to the rolling surface is randomized, or the ratio of the degree of orientation of the {100} crystal plane is increased. Then, the etching rate in the depth direction becomes more uniform, and the effect of preventing the occurrence of uneven stripes is further improved.

The degree of orientation of the crystal plane, such as the ratio of the degree of orientation of the {100} crystal plane to the rolled plane, can be determined by X-ray diffraction. The method of identifying the crystal orientation by the X-ray diffraction method is extremely commonly used, for example,
It is described on pages 81 to 82 of "Guide to X-ray Diffraction, Revised 4th Edition" issued by Rigaku Denki Co., Ltd.

The present invention has been completed on the basis of these findings. First, Ni is made of an Fe-Ni-based alloy containing 32 to 38 mass%, and the rolling direction in the plane to be etched is described. The concentration fluctuation amount of Ni micro-segregation in the direction orthogonal to is 2 mass% or less, and the width of the concentration fluctuation part is
An object of the present invention is to provide a low-thermal-expansion alloy thin plate for electronic parts having excellent etching properties, which is used as a base plate of a product having a hole pitch of 300 μm or less by etching, which is 500 μm or less.

Second, Ni: 23 to 38 mass%, Co: 7 m
Fe containing less than ass% and Ni + Co of 32 to 38 mass%
-Ni-Co-based alloy, the concentration fluctuation amount of Ni micro-segregation in the direction perpendicular to the rolling direction in the plane to be etched is 2 mass% or less, and the width of the concentration fluctuation portion is 50%
An object of the present invention is to provide a low-thermal-expansion alloy thin plate for electronic components excellent in etching properties, which is used as a base plate of a product having a hole pitch of 300 μm or less by etching and characterized by being not more than 0 μm.

Third, the Ni-segregation is made of an Fe-Ni-based alloy containing 32 to 38 mass% of Ni, and the concentration fluctuation of Ni microsegregation in the direction orthogonal to the rolling direction in the plane to be etched is 2 mass%. And the width of the density fluctuation part is
Characterized in that the orientation ratio of the {100} crystal plane to the rolled surface (%) is 20 to 40% or 80% or more.
An object of the present invention is to provide a low-thermal-expansion alloy thin plate for electronic parts having excellent etching properties, which is used as a base plate for products of 300 μm or less.

Fourth, Ni: 23-38 mass%, Co: 7 m
Fe containing less than ass% and Ni + Co of 32 to 38 mass%
-Ni-Co-based alloy, the concentration fluctuation amount of Ni micro-segregation in the direction perpendicular to the rolling direction in the plane to be etched is 2 mass% or less, and the width of the concentration fluctuation portion is 50%
0 μm or less and the orientation ratio (%) of {100} crystal plane to the rolled surface is 20 to 40% or 80% or more.
An object of the present invention is to provide a low-thermal-expansion alloy thin plate for electronic components having excellent etching properties, which is used as a base plate for products having a size of 0 μm or less.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

In the present invention, the amount of concentration fluctuation of Ni micro-segregation in the direction perpendicular to the rolling direction in the plane to be etched is 2 mass% or less, and the width of the concentration fluctuation portion of Ni micro-segregation is 500 μm or less. is required.

If the variation in the concentration of Ni micro-segregation exceeds 2 mass%, the difference in the etching rate due to the variation in the concentration of the Ni component is large, so that stripe unevenness occurs. On the other hand, when the width of the concentration fluctuation portion of Ni micro-segregation exceeds 500 μm, a difference in etching rate occurs due to the rows of rows of etching processes,
Streaks occur. Therefore, it was limited to the above range.

Also, when the orientation ratio of the {100} crystal face to the rolled face is set to 20 to 40% or 80% or more, the etching rate in the depth direction becomes more uniform, and the effect of preventing the occurrence of uneven stripes is obtained. Is more improved.

Further, the concentration fluctuation amount of Ni micro-segregation is 1 mass%.
When the width is less than or equal to 200 μm and the width of the density variation portion is within 200 μm or less, the effect of preventing the occurrence of uneven stripes is further improved. Therefore, in order to obtain better etching properties,
More preferably, the amount of concentration fluctuation of Ni microsegregation is 1 mass% or less, and the width of the concentration fluctuation portion is 200 μm or less.

In particular, the concentration fluctuation of Ni micro-segregation is 1 mass%.
Below, and the width of the concentration fluctuation portion is within the range of 200μm or less, and when the orientation ratio of the {100} crystal plane to the rolled surface is within the above range, no line unevenness occurs.
Particularly preferred.

FIG. 1 shows that the hole pitch of the etching process is 300
Fe-36mass% Ni alloy thin plate that becomes the base plate of products of μm or less,
FIG. 9 is a graph showing the relationship between the concentration fluctuation amount of Ni microsegregation, the width of the concentration fluctuation portion, and the occurrence of streak unevenness when the orientation ratio of the {100} crystal plane is 20 to 40% or 80% or more. FIG.
The plots in the middle correspond to the examples described later. In the examples, the evaluations of 〜 to ◎ are represented by the symbol ○ in FIG.

As shown in FIG. 1, when the amount of concentration fluctuation of Ni microsegregation is 2 mass% or less and the width of the concentration fluctuation portion is 500 μm or less, almost no line unevenness occurs, and the shadow mask is not used. Good etching properties without any problem can be obtained. Further, when the amount of concentration fluctuation of Ni micro-segregation is 1 mass% or less and the width of the concentration fluctuation portion is 200 μm or less, no line unevenness occurs.

In the present invention, in order to obtain a sufficiently low thermal expansion property so as not to cause dimensional change or misalignment which deteriorates the performance of electronic parts, Fe-Ni containing 32 to 38 mass% of Ni is used.
A system alloy is used. By using such an alloy,
A low-thermal-expansion alloy sheet having an average coefficient of thermal expansion from room temperature to 100 ° C. of 2.0 × 10 ⁻⁶ / ° C. or less is realized.

In another embodiment of the present invention, 7 mass
An Fe-Ni-Co alloy to which s% or less of Co is added is used. In this case, Ni: 23 to 38 mass%, Co: 7 mass% or less,
And Ni + Co is 30 to 38 mass%. By using an alloy having such a composition, the same low thermal expansion property as that of the above-mentioned Fe-Ni-based alloy can be obtained. If Co exceeds 7% by mass, the etching property is significantly reduced, so the upper limit of the amount of Co is set to 7% by mass.

The alloy of the present invention further comprises, in addition to the above elements,
Si ≦ 0.07mass%, Mn ≦ 0.5mass%, B ≦ 0.02mass%, N ≦
It may contain 0.005 mass% and O 2 ≦ 0.002 mass%. Even if these components are contained in the above range, the effects of the present invention are not impaired.

Of these elements, Si can be used as a deoxidizing element for molten steel. However, if it is present in excess, it is concentrated in the surface layer of the plate during the blackening treatment, and the formation of a uniform and black oxide film is hindered. It is desirable to be 0.07 mass% or less. Mn is useful for ensuring good hot workability, but if it is present in excess, it reduces the etchability, and because of the blackening treatment, it concentrates on the surface layer of the plate and hinders the formation of a uniform and black oxide film. , 0.5 mass% or less. B has the effect of improving hot workability and suppressing scale formation.However, if it is present excessively, it is concentrated in the surface layer of the plate during the blackening treatment and hinders the formation of a homogeneous black oxide film.
It is desirable to set it to 02 mass% or less. Since N causes deterioration in press workability and etching property, 0.005 mass
It is desirable to be s% or less. O inhibits the growth of crystal grains during softening annealing before pressing and degrades the pressability, so it is preferably 0.002 mass% or less.

Next, a method for producing a low thermal expansion alloy sheet according to the present invention will be described. First, a steel ingot prepared to the above-mentioned composition is melted and subjected to a heat treatment at 1200 to 1300 ° C. for 20 hours or more, and then to a thickness of 160 to 250 mm by slab rolling.
Further, heat treatment is performed at 1050 to 1250 ° C. for 30 minutes or more, and a hot-rolled steel sheet having a thickness of 2 to 3 mm is obtained by hot rolling. This hot-rolled steel sheet is repeatedly subjected to cold rolling and annealing at 750 ° C. or more to produce a thin sheet having a thickness of 0.10 to 0.25 mm. At this time, the cumulative rolling reduction from the steel ingot to the thin plate is 99.9% or more. At this time, the amount of concentration fluctuation and the width of the concentration fluctuation portion of the Ni micro-segregation of the present invention, and the ratio of the degree of orientation of the {100} crystal plane with respect to the rolling surface are determined by electromagnetic stirring when melting the steel ingot having the above-mentioned composition. Prevents the segregation of components and the formation of an abnormal structure, and further adjusts the temperature and time of diffusion heat treatment by soaking the ingot and soaking the slab according to the thickness of the ingot, reducing the cold rolling rate and the temperature of the intermediate annealing. And by adjusting the time.

The present invention is generally applied to an alloy thin plate for an electronic component to be etched, and in particular, a shadow mask having a hole pitch of 300 μm or less by etching with high precision and low thermal expansion. It is suitable as a material for use. Fe having low thermal expansion characteristics in the present invention
Since a shadow mask made of a -Ni-based or Fe-Ni-Co-based alloy thin plate has a small displacement due to thermal expansion, an image of a CRT using the same becomes sharper.

[0045]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the alloy thin plate of the present invention is used as a material for a shadow mask will be described below.

Table 1 shows the chemical composition of the steel used in this example. Here, low thermal expansion properties, blackening properties, and press moldability required for shadow mask materials are obtained.
A to C were melted.

[0047]

[Table 1]

The steel ingot obtained by melting these steels is 1200
Heat treatment was performed at 1300 ° C. for 5 to 50 hours, followed by slab rolling. For some of the materials, the slab obtained above was further subjected to a heat treatment at 1200 to 1300 ° C. for 5 to 50 hours, followed by slab rolling again. Subsequently, heat treatment is performed at 1050-1150 ° C for 1-5 hours, and then hot-rolled to a thickness of 2.0-3.5mm.
Was obtained. Two to four additional cold rollings and 700 ° C
Annealing at the above temperature was repeated 1 to 3 times, and the sheet thickness was 0.10
Thin plates Nos. 1 to 22 shown in Table 2 having a thickness of 0.20 mm were manufactured. No.1 ~
18 is the present invention, and Nos. 19 to 24 are comparative examples.

The amount of fluctuation in the concentration of Ni microsegregation, the width of the concentration fluctuation portion, and the orientation ratio of the {100} crystal plane to the rolled surface are adjusted by adjusting the casting conditions when melting the steel ingot, The temperature and time of the diffusion heat treatment were adjusted according to the thickness, and the cold rolling reduction and the temperature and time of the intermediate annealing were adjusted.

The concentration variation of Ni microsegregation in the thin plate, the width of the concentration variation portion, and the orientation ratio of the {100} crystal plane to the rolled surface were investigated. Table 2 shows the survey results.

The concentration fluctuation amount of Ni microsegregation and the width of the concentration fluctuation portion are determined by the Ni concentration distribution curve of the surface in the direction perpendicular to the rolling obtained by the electron beam microanalyzer, specifically, the rolling direction.
A surface analysis was performed in a range of 2 mm and a direction perpendicular to the rolling direction of 5 mm, and an average Ni concentration distribution curve in a direction perpendicular to the rolling direction of 5 mm was obtained. The measurement conditions of the electron beam microanalyzer are: acceleration voltage: 15 kV, electron beam diameter: 20 μm.

Further, the etching property of the thin plate was evaluated. Table 2 also shows the results. The etching performance was evaluated as follows: the electron beam passage hole diameter was 120 μm φ, and the hole pitch was 27
A photoetching perforation test was performed using a photomask of 0 μm, and the degree of uneven stripes was determined for the appearance of the processed shadow mask (n = 4). The photo-etching at this time was performed under the conditions of spraying an aqueous solution of ferric chloride having a solution temperature of 60 ° C. and a concentration of 47 Baume at a spray pressure of 2.0 kgf / cm ² . The degree of streak unevenness was determined by visual observation using transmitted light and reflected light using a one-way light source according to the following criteria. ◎: No uneven streaks ○: Fine uneven streaks ×: Strong uneven streaks

[0053]

[Table 2]

As shown in Table 2, in Nos. 1 to 18 of the examples of the present invention, no or no streak unevenness occurs. On the other hand, in Comparative Examples Nos. 19 to 24,
Since the amount of concentration fluctuation of i microsegregation or the width of the concentration fluctuation part was too large, the difference in the relative etching rate due to the fluctuation of the concentration of the Ni component was promoted, and strong stripe unevenness occurred.

In the examples of the present invention, the width of the Ni concentration fluctuation portion is
If the concentration variation is less than 200 mass% or less than 1 mass%, or the orientation ratio of the {100} crystal plane to the rolled surface satisfies one of 20% to 40% or 80% or more, the etching property is evaluated as good. To ◎, and less occurrence of streak unevenness as compared with the invention examples which do not satisfy the above conditions.

If the width of the Ni concentration fluctuation portion is 200 μm or less, the concentration fluctuation amount is 1 mass% or less, and the orientation ratio of the {100} crystal plane to the rolled surface is 20 to 40% or 80% or more, Is evaluated as ス, and no line unevenness occurs.

[0057]

As described above, according to the present invention,
By using a Fe-Ni-based alloy or a Fe-Ni-Co-based alloy having a specific composition as a raw material, the amount of fluctuation of the concentration of Ni microsegregation and the width of the concentration fluctuation portion are defined within a predetermined range, or furthermore, the distance between the rolling surface and By defining the orientation ratio of the 100 ° crystal plane in a predetermined range, a low thermal expansion alloy thin plate for electronic components having excellent etching properties without occurrence of etching defects such as uneven stripes can be obtained.

The thin plate of the present invention is suitable as a low-thermal-expansion alloy thin plate for electronic parts used as a base plate of a product having a hole pitch of 300 μm or less by etching. The thin plate of the present invention can be used as a material for a shadow mask used in a computer display requiring high-precision processing.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between Ni microsegregation and the occurrence of uneven stripes.

FIG. 2 is a diagram showing a state of Ni microsegregation by an electron beam microanalyzer.

FIG. 3 is a schematic diagram showing a state in which stripe unevenness occurs in a shadow mask after etching.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masaki Omura 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd.

Claims (4)

[Claims] 1. Ni: Fe--Ni-based alloy containing 32 to 38 mass%, and the concentration fluctuation amount of Ni micro-segregation in a direction perpendicular to a rolling direction in a plane to be etched is reduced.
2 mass% or less, and the width of the concentration fluctuation part of Ni micro-segregation is 500 μm or more.Excellent etchability used as a base plate for products with a hole pitch of 300 μm or less by etching. Low thermal expansion alloy sheet for electronic parts. 2. A rolling direction in a plane to be etched, comprising a Fe-Ni-Co alloy containing Ni: 23-38 mass% and Co: 7 mass% or less, and Ni + Co being 32-38 mass%. Concentration fluctuation of Ni micro-segregation in the direction perpendicular to
ass% or less, and the width of the concentration fluctuation portion of Ni microsegregation is
A low thermal expansion alloy sheet for electronic components with excellent etching properties, used as a base plate of a product having a hole pitch of 300 μm or less by etching, characterized by being 500 μm or less. 3. Ni: An Fe-Ni-based alloy containing 32 to 38 mass%, and the concentration fluctuation amount of Ni micro-segregation in a direction perpendicular to a rolling direction in a plane to be etched is reduced.
2 mass% or less, and the width of the concentration fluctuation portion of Ni micro-segregation is 500 μm or less, and {100}
For use in electronic parts with excellent etching properties, used as a base plate for products with a hole pitch of 300 μm or less by etching, characterized by a crystal plane orientation ratio (%) of 20-40% or 80% or more. Low thermal expansion alloy sheet. 4. A rolling direction in a plane to be etched, comprising a Fe-Ni-Co alloy containing Ni: 23-38 mass%, Co: 7 mass% or less, and Ni + Co being 32-38 mass%. Concentration fluctuation of Ni micro-segregation in the direction perpendicular to
ass% or less, and the width of the concentration fluctuation portion of Ni microsegregation is
A product with a hole pitch of 300 μm or less, characterized in that the orientation ratio of the {100} crystal plane to the rolled surface (%) is 20 to 40% or 80% or more. Low-thermal-expansion alloy thin plate for electronic components with excellent etching properties used as a base plate for aluminum.