JPH1187219A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device having an alignment mark, which reduces random reflection and can be detected easily and precisely by suppressing the growth of grains during heat treatment, and a method of manufacture thereof. SOLUTION: An alignment mark 12 has a set of two horizontal strips 12a lying in parallel to each other with a predetermined spacing d, and a set of two vertical strips 12b lying in parallel to each other with the same spacing d. The strips are made of an aluminum alloy film formed on a silicon oxide film 11 on a substrate 10, wherein the width W of each of the stripes 12a and 12b is made smaller than 5 μm, or the thickness t of the each is made smaller than 0.3 μm. By making the width W or the thickness t of the each strip smaller than the specified value, the growth of the grains in the strips during heat treatment is suppressed, and their random reflection coefficient is reduced. As a result of the prevention of the random reflection the detection of the alignment mark facilitated and enhances the alignenment accuracy, resulting in the prevention of the occurrence of failure of the products.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a semiconductor device having an alignment mark and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a process of manufacturing a semiconductor device, it is necessary to align a wafer during lithography processing, laser trimming, and the like. As an invention related to an alignment mark used for this alignment, for example, there is one described in Japanese Patent Application Laid-Open No. 7-221166. This is because a high reflectance aluminum band is formed in a cross shape that is orthogonal to the X and Y directions, for example, in order to make it easier to aim at the time of performing alignment on a video monitor. A cross-shaped low reflectance pattern is formed at the center in the width direction along the X and Y directions.

[0003] As described in the above-mentioned publication, there is a demand that the shape of the alignment mark should be devised so that it can be easily recognized and that it can be clearly detected optically. However, in an alignment mark formed of an aluminum alloy film in a conventional semiconductor device, grains grow when heat treatment is applied, and irregular reflection occurs when a reference beam is applied to detect the alignment mark, thereby deteriorating the mark detection accuracy during alignment. I do.

For example, a substrate provided with an alignment mark having a thickness of 1 [μm] and a line width of about 10 [μm] made of an aluminum alloy has a temperature of 450 [° C.] and 30 [m].
In], heat treatment for stabilizing transistor characteristics is performed. By this heat treatment, grains having a diameter of about 10 [μm] grow at some points on the alignment mark.
Due to the growth of the grains, the reference light for alignment is irregularly reflected.

In order to prevent the growth of grains, there is a method of covering an alignment mark of an aluminum alloy having a thickness of 1 [μm] with a titanium nitride film having a thickness of about 0.1 [μm]. . In this case, since the aluminum alloy is covered with titanium nitride, it is known that the grains do not grow even by heat treatment for stabilizing transistor characteristics at, for example, 450 ° C. for 30 minutes after the alignment mark is formed. ing.

[0006]

Since the conventional semiconductor device is configured as described above, there are the following problems. That is, for example, when heat treatment is performed to stabilize transistor characteristics, grains grow on the alignment of the aluminum alloy film, and the reference light is irregularly reflected. For this reason, there has been a problem that the detection accuracy of the alignment mark is reduced. Further, when the grains grow large, the large grains themselves may be erroneously recognized as alignment marks.

In order to solve this problem, when the surface of the alignment mark is covered with titanium nitride, the growth of grains can be suppressed. However, since the reflectance of titanium nitride is lower than the reflectance of an aluminum alloy, the alignment mark is poor. Was disadvantageous for the detection of

The present invention has been made to solve the above-mentioned problems, and has the following object. A semiconductor device which has an alignment mark which has a small grain growth, a high reflectance, and which can be easily and accurately detected, can perform high-precision alignment, and can prevent the occurrence of product defects. Provided is a method of manufacturing a semiconductor device which can form an alignment mark having a high reflectivity while suppressing the growth of grains, perform high-accuracy alignment, and prevent the occurrence of product defects.

[0009]

In order to achieve the above object, a semiconductor device according to the present invention has:
It is formed in a strip shape with a metal material on a substrate and has a width of 5 [μm] or less or a thickness of 0.3 [μm].
An alignment mark having the following belt-like body is provided. If you limit the width or thickness of the band,
Grain growth during heat treatment is suppressed. By suppressing the growth of grains, irregular reflection of the strip can be prevented, and the alignment mark can be easily and accurately detected.

The alignment marks are formed by arranging two strips in parallel at a predetermined interval. Position detection can be performed by scanning the parallel strips across with a light beam.

Further, the alignment mark may be provided with a connecting portion for connecting two band-shaped bodies arranged in parallel at a predetermined position. Position detection can be performed by scanning this connecting portion across with a light beam, which is substantially the same as a strip having a width twice or more.

Further, the alignment mark may be formed by arranging the first band and the second band in an L shape.

[0013] The metal material forming the strip is an aluminum alloy or copper.

Further, in the method of manufacturing a semiconductor device according to the present invention, a step of forming a conductive layer of a predetermined thickness with a metal material on a substrate, and a step of forming a wiring of a predetermined thickness by etching the conductive layer. Forming a strip having a layer and a width of 5 μm or less or a thickness of 0.3 μm or less, and using the strip as an alignment mark.

The step of forming a strip and using the strip as an alignment mark includes an etch-back step of etching back the conductive layer to form a strip having a thickness of 0.3 [μm] or less. Things. The conductive layer is etched to form a wiring layer and a strip, but the thick conductive layer can be etched back to form a strip of 0.3 [μm] or less. The thickness can be selected without being limited by the thickness of the body, and the resistance of the wiring layer can be reduced.

The method of manufacturing a semiconductor device according to the present invention includes the steps of: forming a conductive layer of a predetermined thickness from a metal material on a substrate; forming a coating layer on the conductive layer; And performing a predetermined heat treatment by etching the conductive layer to form a wiring layer having a predetermined thickness and a predetermined width of the band-like body covered with the coating layer, the coating layer serving as an anti-reflection film. After that, removing the coating layer on the belt-like body to make the belt-like body an alignment mark. When performing a predetermined heat treatment, the coating layer on the band suppresses the growth of grains in the band. Then, since the coating layer is removed after the heat treatment to form an alignment mark, it is not necessary to strictly limit the width and thickness of the belt-like body, and the degree of freedom is increased.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a plan view showing a main part of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along section line II-II in FIG. FIG. 3 is an explanatory diagram showing the relationship between the grain size of the alignment mark and the reflectance. 4 to 7 are cross-sectional views for explaining a process of manufacturing the semiconductor device of FIG. In these figures, 10 is a silicon substrate, 11 is a silicon oxide film formed on the silicon substrate, and 12 is an alignment mark provided on the silicon oxide film 11.

The alignment mark 12 includes two horizontal strips 12a arranged in parallel at a predetermined interval d, two vertical strips 12b similarly arranged in parallel at an interval d, and two horizontal strips 12b. A connecting portion 12c for connecting the band 12a at the right end in FIG. 1 and a connecting portion 12d for connecting the two vertical bands 12b at the upper end in FIG. 1. The horizontal band 12a and the vertical band 12b They are arranged in an L shape so as to be orthogonal.

The horizontal band 12a, the vertical band 12b, and the connecting portions 12c, 12d are formed, for example, by forming an aluminum alloy film having a line width W of 4 [μm] and a thickness t of 1 [μm] with a distance d of 2 [μm].
[Μm] and formed on the silicon oxide film 11. The connection width and the connection length of the connection portions 12c and 12d are each 2 [μm]. The connecting portions 12c and 12d connect the horizontal strips 12a and the vertical strips 12b to each other to improve the adhesion strength with the silicon oxide film 11.

Reference numeral 13 denotes a wiring pattern formed on the silicon oxide film 11, which is formed of the same aluminum alloy as the alignment mark 12, and has a thickness of 1 μm and a width of 10 μm.
[Μm]. Although details will be described later, in this embodiment, the alignment mark 12 is formed simultaneously when the wiring pattern 13 is formed on the silicon oxide film 11. 14 is an antireflection film of titanium nitride,
Light is prevented from being reflected on the wiring pattern 13.
Reference numeral 15 denotes an insulating film of silicon nitride having a thickness of 1 [μm], which covers the antireflection film 14 and the wiring pattern 13. Specific examples of the aluminum alloy include aluminum-1% silicon, aluminum-1% silicon-0.5
% Copper and the like.

A light beam for position detection scans the two horizontal strips 12a in the direction of arrow A, which is the vertical direction in FIG. 1, and moves the two vertical strips 12b in the direction of arrow B, which is the horizontal direction. Scan and detect position.

As described above, the line width of the horizontal band 12a, the vertical band 12b, and the connecting portions 12c and 12d constituting the alignment mark 12 is set to 5 [μm] or less. It is for the following reasons.

When the grain size of the alignment mark 12 increases, the ratio of irregular reflection of the laser beam increases, and the reflectance decreases. FIG. 3 shows the relationship between the grain size [μm] and the reflectance [%] of the strips 12 a and 12 b formed of the aluminum alloy film forming the alignment mark 12. According to FIG. 3, in order to ensure a reflectance of 80% or more, a grain size of 5
It is desirable to suppress it to about [μm]. On the other hand, according to an experiment performed by the inventor of the present invention, the film thickness is more than
m] or more, after the alignment mark 12 is formed, predetermined heat treatment, for example, 450 [° C.], 30 [m
In], it was found that when the heat treatment for stabilizing the transistor characteristics was performed, the average grain size of the grains grown by the heat treatment could be suppressed to be equal to or less than the width of the alignment mark.

In this embodiment, the horizontal band 1
The line width W of the 2a and the vertical band 12b is 4 [μm], the film thickness is 1 [μm], and the average grain size of the grown grains can be suppressed to about 4 [μm]. Therefore, if the width W of each strip constituting the alignment mark is set to 5 [μm] or less, the growth of the grain size is suppressed to 5 [μm] or less even when the heat treatment at 450 [° C.] and 30 [min] is performed. As a result, there is no possibility that the grains will grow large and cause irregular reflection of the reference light to lower the reflectance.

Here, a method of manufacturing the semiconductor device shown in FIGS. 1 and 2 will be described with reference to FIGS. First, as shown in FIG. 4, a metal layer 16 made of an aluminum alloy and having a thickness of 1 [μm] is formed on the silicon oxide film 11 by a plasma sputtering method. Next, a coating layer 17 of titanium nitride having a thickness of 0.1 [μm] is formed on the metal layer 16. A resist pattern 18 for forming the alignment mark 12 and the wiring pattern 13 on the coating layer 17;
19 is formed.

Thereafter, the covering layer 17 and the metal layer 16 are patterned by performing anisotropic etching on the state shown in FIG. 4, and the alignment mark 12 and the covering layer 17 covered with the covering layer 17 are covered. The wiring pattern 13 is formed. The covering layer 17 on the wiring pattern 13
Is formed on the antireflection film 14. Further, the resist patterns 18 and 19 are removed to obtain the state shown in FIG. Thus, the alignment mark 12 is formed simultaneously with the wiring pattern 13.

The state shown in FIG. 5 is entirely covered with an insulating film 20 made of silicon nitride to form the state shown in FIG. The resist pattern shown in FIG.
State. That is, as shown in FIG. 7, the resist pattern 21 covers the wiring pattern 13 and the antireflection film 14, but does not cover the covering layer 17 and the alignment mark 12.

The insulating film 20 is partially etched away by performing anisotropic etching with respect to the state shown in FIG.
(Titanium nitride) is removed by etching. As described above, the alignment mark 12 shown in FIGS.
Is manufactured.

Embodiment 2 FIG. 8 is a plan view showing a main part of another embodiment of the present invention. In FIG. 8, an alignment mark 32 is formed by connecting two horizontal strips 12a on the left side of a link 12c by a left link 32a so as to form a vertical scanning section 32c as an integral unit. Are connected to each other by a lower connecting portion 32b below the connecting portion 12d in FIG. 8 to integrally form a horizontal scanning portion 32d as shown in the figure.

The left connecting portion 32a and the lower connecting portion 32b are
Like the horizontal band 12a and the vertical band 12b, the thickness is 1 [μ].
m], the connection width C is 5 μm, and the connection length is 2 μm corresponding to the interval d. Note that the light beam for position detection is transmitted to the vertical scanning unit 3.
2c is scanned in the direction of arrow A, and the horizontal scanning unit 32d is moved in the direction of arrow B.
Scan in the direction to detect the position. In this case, the substantial width of the alignment mark 32 in the direction of each of the arrows A and B, which is the scanning direction, is 10 [μm].

The other components are the same as those shown in FIGS. 1 and 2, and the corresponding components are denoted by the same reference numerals and description thereof will be omitted. This semiconductor device is also shown in FIG.
Is manufactured by a process similar to that shown in FIG.

Also in this embodiment, by setting the line width of each part to 5 [μm] or less, for example, 450 [° C.] and 30 [mi] after the alignment mark 32 is formed.
n], the growth of grains due to the heat treatment for stabilizing the transistor characteristics is suppressed as compared with the conventional case as shown in FIG. 1, and the irregular reflection of the reference light is reduced. Further, since each of the scanning sections 32c and 32d, which are scanned by the beam for position detection, has a substantial width in the scanning direction of 10 [μm], similarly to the conventional alignment mark, the setting of the position detection mechanism is changed. No need.

Embodiment 3 9 and 10 show a main part of another embodiment of the present invention.
FIG. 10 is a plan view, and FIG. 10 is a cross-sectional view taken along the line XX in FIG. The semiconductor device according to this embodiment includes:
The thickness of the alignment mark strip is reduced to suppress grain growth. 9 and 10,
In the alignment mark 42, a horizontal band 42a and a vertical band 42b formed in a film shape of an aluminum alloy having a line width W of 10 [μm] and a thickness t of 0.3 [μm] are orthogonal to the L shape. It is arranged as in. The horizontal band 42a and the vertical band 42b are formed directly on the silicon oxide film 11 without any intervening barrier metal.
Other configurations are the same as those shown in FIGS.

Next, a method of manufacturing the semiconductor device shown in FIGS. 9 and 10 will be described. Through a process similar to that shown in FIGS. 4 and 5, the wiring pattern 13 having a thickness t of 1 [μm] and a band-shaped metal layer for the horizontal band 42a and the vertical band 42b are formed. At this time, the wiring pattern 13
A coating layer 14 serving as an anti-reflection film is provided on the horizontal band 4.
The covering layer 17 remains on the band-shaped metal layer for the 2a and the vertical band-shaped body 42b, and is in a state similar to FIG. However,
The width W of the band-shaped metal layer for the horizontal band 42a and the vertical band 42b is 10 [μm].

Next, the whole is covered with the insulating film 15 to make the same state as in FIG. 6, and furthermore, the portion of the wiring pattern 13 is masked, and the portion of the band-shaped metal layer for the horizontal band 42a and the vertical band 42b is formed. Is etched back so that the film thickness t becomes 0.3 [μm], thereby obtaining a semiconductor device having a sectional structure as shown in FIG. This semiconductor device has the same advantages as those shown in FIG.

9 and 10, the horizontal band 42
a and the vertical strips 42b are as thin as 0.3 [μm], so that the grains are 5 even by heat treatment for stabilizing transistor characteristics of, for example, 450 [° C.] and 30 [min].
There is no large growth exceeding [μm]. According to an experiment by the inventor, when the film thickness is 0.3 [μm] or less,
For example, even when heat treatment at 450 [° C.] and 30 [min] was performed, it was found that the average grain size of the grains did not grow significantly beyond 5 [μm]. At this time, the width of the strip hardly affects the grain growth.

On the other hand, although the wiring pattern 13 is in the same layer as the horizontal band 42a and the vertical band 42b of the alignment mark 42, the wiring pattern 13 has a thickness of 1 [μm] and therefore can have a low resistance. Further, since the planar shape of the alignment mark 42 is the same as that of the conventional one, there is no need to change the setting of the position detection mechanism, and it is not necessary to change the mask pattern.

Embodiment 4 FIG. FIG. 11 is a sectional view showing a main part of another embodiment of the present invention. In FIG. 11, reference numeral 51 denotes a barrier metal layer, and a titanium film 51a laid on the silicon oxide film 11 and the titanium film 51a.
And a titanium nitride film 51b formed thereon. On the barrier metal layer 51, the wiring pattern 13 and the alignment mark 52 are formed. The wiring pattern 13 has a width of 10 [μm] and a thickness of 1 [μm], and an antireflection film 14 having a thickness of 0.1 [μm] is formed thereon. The horizontal strips (not shown, but similar to the horizontal strips 42a in FIG. 9) and the vertical strips 52b that form the alignment mark 52 are made of an aluminum alloy having a thickness of 0.3 mm.
[Μm] films are formed in an L shape so as to be perpendicular to each other.

As can be generally said, the size of the grains grown during the heat treatment greatly depends on the underlying film, and when the underlying film is made of titanium nitride (barrier metal), the silicon oxide film is formed. Is smaller than the case where According to an experiment by the inventor, in the case of an aluminum alloy strip formed on two barrier metal layers of titanium and titanium nitride, aluminum grains grown by heat treatment at about 450 [° C.] and about 30 [min] are used. The maximum average particle size was about three times the film thickness. Therefore, in the case of this embodiment,
The size of the grain can be reduced to 1 [μm], and a better reflectance can be obtained.

Embodiment 5 12 to 17 show still another embodiment of the present invention. FIG. 12 is a plan view illustrating a main part of the semiconductor device, and FIG. 13 is a cross-sectional view taken along section line XIII-XIII in FIG. 14 to 17 are cross-sectional views for explaining a method of manufacturing the semiconductor device of FIGS.

In FIGS. 12 and 13, the alignment mark 62 has a horizontal band 62a and a vertical band 62b formed of an aluminum alloy having a line width of 10 [μm] and a thickness of 1 [μm]. They are arranged so as to be orthogonal to the mold. Horizontal band 62a and vertical band 62b
Is the silicon oxide film 11 without the intervention of a barrier metal.
Is formed directly on 12 and 13 are different from those shown in FIG. 1 and have been subjected to a predetermined heat treatment, for example, a heat treatment for stabilizing transistor characteristics at 450 [° C.] and 30 [min]. Things.
Other configurations are the same as those shown in FIGS.

Next, a method of manufacturing the semiconductor device shown in FIGS. 12 and 13 will be described. First, as shown in FIG. 14, a metal layer 16 made of an aluminum alloy and having a thickness of 1 [μm] is formed on a silicon oxide film 11 by a plasma sputtering method. Next, a coating layer 17 of titanium nitride having a thickness of 0.1 [μm] is formed on the metal layer 16.
Resist patterns 61 and 19 for forming alignment marks 62 and wiring patterns 13 on coating layer 17
To form

Thereafter, the coating layer 17 and the metal layer 16 made of an aluminum alloy are patterned by performing anisotropic etching on the state shown in FIG.
7 (vertical strip 62)
b) and the wiring pattern 13 covered with the antireflection film 14 is formed. Further, the resist patterns 19 and 61 are removed to obtain the state shown in FIG. Thus, the alignment mark 62 is formed simultaneously with the wiring pattern 13.

The structure shown in FIG. 15 is entirely covered with an insulating film 20 made of silicon nitride, and a resist pattern 21 is formed on the insulating film 20 to obtain the state shown in FIG.
The wiring pattern 13 and the antireflection film 14 are covered with the resist pattern 21, and the coating layer 17 and the alignment mark 6 are formed.
2 is not covered.

In FIG. 17, alignment mark 62
The vertical band 62b formed of the aluminum alloy film is covered with the coating layer 17 of titanium nitride. The structure shown in FIG. 17 is subjected to heat treatment for stabilizing transistor characteristics at, for example, 450 [° C.] and 30 [min]. At this time, since the aluminum alloy film 62 is covered with the coating layer 17, the growth of grains is suppressed.

After the heat treatment is completed, the coating layer 17 (titanium nitride) covering the alignment mark 62 is removed by etching. As described above, a semiconductor device having the alignment marks 62 as shown in FIGS. 12 and 13 and having undergone a predetermined heat treatment is manufactured. Since the planar shape of the alignment mark 62 is the same as that of the related art, there is no need to change the setting of the position detection mechanism, and it is not necessary to change the mask pattern.

In the above embodiment, the metal forming the belt-like body is an aluminum alloy. However, the same effect can be obtained with other metals, such as copper. Further, the alignment mark strip is not limited to be formed simultaneously with the wiring pattern, and the alignment mark may be formed later. In the embodiments shown in FIGS. 1, 8 and the like, if the thickness of each band is smaller than 1 [μm], for example, about 0.5 [μm], the growth of grains can be further suppressed. it can.

Further, the shape of the alignment mark is not limited to the shape in which the band is disposed on the L, but may be a plurality of lines having a different shape, for example, a plurality of linear bands having a width of 5 [μm]. It may be provided on a substrate. It is to be noted that if the same barrier metal layer 51 as shown in FIG. 11 is applied to the embodiments shown in FIGS. 1, 8, 9 and 12, the growth of grains can be further suppressed.

[0049]

As described above, according to the present invention, a band is formed of a metal material on a substrate and has a width of 5 [μm] or less or a thickness of 0.3 [μm]. Since the alignment mark having the following band is provided, the growth of the grain in the heat treatment is suppressed by restricting the width or the thickness of the band, and the irregular reflection of the band is prevented. Detection is easy and highly accurate alignment can be performed.
Product failure can be prevented.

The alignment marks are formed by arranging two strips in parallel at a predetermined interval.
Detection can be performed by scanning the parallel strips across with a light beam, which facilitates detection.

Further, since the alignment mark is provided with a connecting portion for connecting the two strips arranged in parallel at a predetermined position, the alignment mark is detected by scanning across the connecting portion with a light beam. Can be performed, and the width is substantially the same as that of a band having a width of twice or more, and detection is easy.

If the alignment mark is formed by arranging the first band and the second band in an L shape, positioning on a two-dimensional plane is easy.

Since the metal material forming the band is made of an aluminum alloy or copper, the conductive layer may be made of an aluminum alloy or copper, and may be formed simultaneously with the band.

Further, in the method of manufacturing a semiconductor device according to the present invention, a step of forming a conductive layer of a predetermined thickness with a metal material on a substrate, and a step of forming a wiring of a predetermined thickness by etching the conductive layer. Forming a strip having a layer and a width of 5 μm or less or a thickness of 0.3 μm or less and using the strip as an alignment mark, so that the width or thickness of the strip is reduced. By limiting the growth of grains during heat treatment by restricting, and preventing irregular reflection of the band-like body, it becomes easy to detect the alignment mark, it is possible to perform highly accurate alignment, and it is possible to prevent the occurrence of product defects. A method for manufacturing the device can be provided.

In the step of forming a strip and using the strip as an alignment mark, an etch-back step of etching back the conductive layer to form a strip having a thickness of 0.3 [μm] or less is provided. Therefore, a thick conductive layer can be etched back to form a strip of 0.3 [μm] or less, and the thickness of the wiring layer can be selected to be thick without being limited to the thickness of the strip. In addition, the resistance of the wiring layer can be reduced.

The method of manufacturing a semiconductor device according to the present invention includes the steps of forming a conductive layer of a predetermined thickness with a metal material on a substrate, forming a coating layer on the conductive layer, And performing a predetermined heat treatment by etching the conductive layer to form a wiring layer having a predetermined thickness and a predetermined width of the band-like body covered with the coating layer, the coating layer serving as an anti-reflection film. And removing the coating layer on the band after forming the band to make the band an alignment mark, so that when the predetermined heat treatment is performed, the growth of the grains in the band by the coating layer on the band is performed. Can be suppressed,
Since the coating layer is removed after the heat treatment to form an alignment mark, it is not necessary to set strict restrictions on the width and thickness of the strip, and a semiconductor device having an alignment mark with a high degree of freedom can be manufactured.

[Brief description of the drawings]

FIG. 1 is a plan view showing a main part of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a section taken along a cutting line II-II in FIG. 1;

FIG. 3 is an explanatory diagram showing a relationship between a grain size of an alignment mark and a reflectance.

FIG. 4 is a cross-sectional view for explaining a manufacturing process of the semiconductor device of FIG. 1;

FIG. 5 is a cross-sectional view for explaining a manufacturing process of the semiconductor device of FIG. 1;

FIG. 6 is a cross-sectional view for explaining a manufacturing process of the semiconductor device of FIG. 1;

FIG. 7 is a cross-sectional view for explaining a manufacturing process of the semiconductor device of FIG. 1;

FIG. 8 is a plan view showing a main part of a semiconductor device according to another embodiment of the present invention.

FIG. 9 is a plan view showing a main part of a semiconductor device according to another embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a cross section taken along a cutting line XX in FIG. 9;

FIG. 11 is a cross-sectional view showing a main part of a semiconductor device according to another embodiment of the present invention.

FIG. 12 is a plan view showing a main part of a semiconductor device according to another embodiment of the present invention.

FIG. 13 is a sectional view showing a section taken along a cutting line XIII-XIII in FIG. 12;

FIG. 14 is a cross-sectional view for explaining a manufacturing process of the semiconductor device in FIG. 12;

FIG. 15 is a cross-sectional view for explaining a manufacturing process of the semiconductor device in FIG. 12;

FIG. 16 is a cross-sectional view for explaining a manufacturing process of the semiconductor device of FIG. 12;

FIG. 17 is a cross-sectional view for explaining the manufacturing process of the semiconductor device in FIG. 12;

[Explanation of symbols]

10 substrate, 11 silicon oxide film, 12 alignment mark, 12a horizontal band, 12b vertical band,
13 wiring pattern, 16 metal layer, 17 coating layer, 3
2 Alignment mark, 32a Left connecting part, 32b
Lower connecting portion, 32c horizontal scanning portion, 32d vertical scanning portion, 42 alignment mark, 42a horizontal band,
42b vertical strip, 51 barrier metal layer, 52 alignment mark, 52b vertical strip, 62 alignment mark, 62a horizontal strip, 62b vertical strip.

Claims (8)

[Claims] 1. An alignment mark having a band formed of a metal material on a substrate and having a width of 5 μm or less or a thickness of 0.3 μm or less. Equipped semiconductor device. 2. The semiconductor device according to claim 1, wherein the alignment mark is formed by arranging two strips in parallel at a predetermined interval. 3. The semiconductor device according to claim 2, wherein the alignment mark is provided with a connecting portion that connects two strips arranged in parallel at a predetermined position. 4. The semiconductor device according to claim 1, wherein the alignment mark is formed by arranging a first band and a second band in an L shape. 5. The semiconductor device according to claim 1, wherein the metal material is an aluminum alloy or copper. 6. A step of forming a conductive layer of a predetermined thickness with a metal material on a substrate, and etching the conductive layer to form a wiring layer of a predetermined thickness and a width of 5 [μm] or less. Forming a strip having a thickness of 0.3 [μm] or less, and using the strip as an alignment mark. 7. The step of forming a strip and using the strip as an alignment mark includes an etch-back step of etching back the conductive layer to form a strip having a thickness of 0.3 [μm] or less. 7. The method for manufacturing a semiconductor device according to claim 6, wherein: 8. A step of forming a conductive layer of a predetermined thickness with a metal material on a substrate, a step of forming a coating layer on the conductive layer, and etching the coating layer and the conductive layer. Forming a strip of a predetermined width covered with the wiring layer and the coating layer having a predetermined thickness by using the coating layer as an anti-reflection film, and coating the strip on the strip after performing a predetermined heat treatment. Removing the layer to use the strip as an alignment mark.