JP3046003B2 - Glass substrate for electronic device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass substrate for an electronic device used as a mask substrate or the like in the manufacture of a semiconductor integrated circuit and a method for manufacturing the same.

[0002]

2. Description of the Related Art For example, an electronic device made of soda-lime glass, borosilicate glass, fused silica, or the like has been used as a mask substrate for performing photolithography in the manufacture of a semiconductor integrated circuit. Glass substrates are used. The glass substrate for an electronic device is usually mirror-finished on the surface, and a light-shielding film such as chromium or chromium oxide is formed thereon by a vacuum deposition method, a sputtering method, or the like. After a predetermined pattern is formed on the light-shielding film, it is used as a mask substrate in a semiconductor manufacturing process.

Incidentally, the process of manufacturing a mask substrate from a glass substrate for an electronic device needs to be performed in an extremely clean environment. In particular, when the light-shielding film is formed, if dust, fine particles such as abrasives, glass chips, or other foreign matters are mixed in the light-shielding film, fatal holes such as pinholes are formed when forming a putter on the light-shielding film. Serious defects occur frequently.

For this reason, as the glass substrate for an electronic device, a foreign substance such as an abrasive is trapped during a mask substrate manufacturing process, or a chip is generated during the process to generate a foreign substance on a glass chip by itself. It is not required to do so. For this reason, conventionally, the side peripheral portion of the electronic device glass substrate is mirror-finished so that there is no room for capturing foreign substances such as abrasives, or a predetermined surface is provided on the side peripheral portion of the substrate. It is known that chipping is performed so that chipping hardly occurs (for example,
See Japanese Patent Publication No. 61-34669).

FIGS. 2 to 4 are partial cross-sectional views of a conventional glass substrate for an electronic device. In the figure, reference numeral 11 denotes a glass substrate main body, reference numeral 12 denotes a front surface, reference numeral 13 denotes a back surface, and reference numeral 14 denotes a side surface.

In FIG. 2, flat sloping slopes 15 and 16 are formed by chamfering ridges where the front and back surfaces 12 and 13 intersect with the side surface 14, respectively. Also, what is shown in FIG.
And 13 and the side surface 14 are formed with rounded ridge lines. Further, what is shown in FIG. 4 is one in which the entire side surface 14 is formed round.

[0007]

As shown in FIGS. 2 to 4, the glass substrate for an electronic device is cut into a wedge-like shape during the manufacturing process of a mask substrate or the like, as shown in FIGS. The glass substrate main body 11 is held and conveyed by pressing the side surface 14 of the glass substrate main body 11 against the chip holder 21.

At this time, in the example shown in FIG. 2 of the conventional examples, since the flat chamfered slopes 15 and 16 abut on the notch holding portion 21, it can be surely held. There are advantages. However, the ridges where the chamfered slopes 15 and 16 intersect with the front and back surfaces 12 and 13 and the side surface 14 are sharp.
For this reason, when holding | maintaining the said glass substrate 11, or when releasing holding | maintenance, it turned out that these ridge lines touch the board | substrate holding jig 20, and the accident which a chip | chip produces | generates occurs not a little.

In the example shown in FIG. 3, the contact between the substrate holding jig 20 and the glass substrate body 11 is close to a point or line contact. It has been found that there is a problem that an excessive force is applied to cause a minute crack or the like, or a fine glass chip is generated due to strong friction at the time of holding.

Further, the example shown in FIG.
As compared with the examples shown in FIGS. 3 and 3, the problems in these examples are alleviated to some extent. However, it has been found that these problems cannot be completely eliminated, because the point or line contact still exists. Moreover, in the examples shown in FIGS. 3 and 4,
It has been found that there is also a problem that the efficiency of removing foreign substances is reduced during cleaning performed in a predetermined process.

That is, generally, cleaning of a glass substrate is performed by:
The process is performed with the glass substrate body 11 standing upright. For this reason, foreign matter adhering to the side surface 12 of the glass substrate main body 11 is washed down from the side surface 12 by a solvent or the like. At this time, as in the example shown in FIG. 2, if a ridge portion where the side surface 14 and the surface 12 intersect is chamfered and a flat inclined surface 15 is formed, FIG. As shown, the foreign matter e slides relatively smoothly on the flat inclined surface 15 and is easily washed off. However, if the entire side surface 14 including the ridges and the ridges is round as in the examples shown in FIGS. 3 and 4, smooth sliding is hindered as shown in FIG. Since the sliding distance is long, the probability of adhesion on the way increases.

Further, in the example shown in FIG. 4, since the entire side surface is round, it becomes difficult to handle the automatic transfer in scrub cleaning, which is a general method of cleaning a mask substrate, and the entire side surface is polished round. Therefore, there is a disadvantage that the production is troublesome.

The present invention has been made under the above-mentioned background, and has a relatively simple structure and does not cause chipping or the like during a manufacturing process of a glass substrate for an electronic device such as a mask substrate. Moreover, it is an object of the present invention to provide a glass substrate for an electronic device that can be easily held during transportation and a method for manufacturing the same.

Means for Solving the Problems As means for solving the above-mentioned problems, the first invention is to flatten a flat glass substrate by chamfering a ridge portion where the front and back surfaces and side surfaces intersect. A chamfered slope is formed, and a ridge portion where the chamfered slope, the front and back surfaces, and the side surfaces intersect is formed to be round so that the radius of curvature R is 0.01 to 0.3 mm. Glass substrate for electronic devices.

According to a second aspect of the present invention, a flat chamfered surface is formed by chamfering a ridge line where the front and back surfaces and the side surface of the plate-like glass substrate intersect with each other. Is present, and the ridges where the chamfered slopes and the front and back surfaces and the side surfaces intersect are each formed so as to have a radius of curvature R of 0.01 to 0.3 mm. A glass substrate for an electronic device, which is a feature.

According to a third aspect of the present invention, a plate-like glass substrate is cut into a predetermined size and shape, the front and back surfaces thereof are roughly polished, and then the ridge portion where the front and back surfaces and the side surfaces of the plate-like glass substrate intersect. A chamfering process is performed to form a flat chamfered slope, and then the chamfered slope and a part of the side and front and back surfaces are polished by brushing to make the chamfered slope and the front and back surfaces and the side surfaces. Are defined by the radii of curvature R
Is rounded so as to be 0.01 to 0.3 mm, and then, the front and back surfaces are finish-polished and then subjected to cleaning.

[0016]

[0017]

In the above structure, since the flat chamfered slope is formed, it is easy to hold the mask substrate during the transportation in a manufacturing process or the like, and an excessive force is locally applied during the holding. There is no risk of cracking or chipping. In addition, since there is a flat chamfered slope, it is easy to wash away foreign substances at the time of cleaning, and efficient cleaning can be performed. In addition, since the chamfered slope, the front and back surfaces, and the side surfaces each have a rounded ridge portion, no chipping or the like occurs in this portion.
In addition, since the polishing for forming these ridge portions in a round shape can be performed relatively quickly, manufacturing is easy.

[0019]

FIG. 1 is a partial sectional view of a glass substrate for an electronic device according to an embodiment of the present invention, FIG. 7 is an enlarged view of a portion A of FIG. 1, and FIG. 8 is a portion B of FIG. It is an enlarged view. Hereinafter, an embodiment of the present invention will be described in detail with reference to these drawings.

In FIG. 1, reference numeral 1 denotes a glass substrate body, reference numeral 2 denotes a front surface, reference numeral 3 denotes a back surface, reference numeral 4 denotes a side surface, reference numerals 5 and 6 denote chamfers, and reference numerals 5a, 5b, 6a and 6b denote ridge portions. It is.

The glass substrate body 1 has a side length of 12
It is a plate having a substantially square shape with a thickness of 7 mm and a thickness of 2.3 mm. The material may be any of soda lime glass, borosilicate glass, fused quartz, etc., but in this embodiment, soda lime glass is used.

The front surface 2 and the back surface 3 of the glass substrate main body 1 are flat surfaces and are mirror-finished.

The chamfered slopes 5 and 6 are formed as flat inclined surfaces by chamfering the ridges at which the front surface 2 and the back surface 3 intersect with the side surfaces 4, respectively. The chamfered slopes 5 and 6 include a reference plane C including the center of the glass substrate main body 1 and being parallel to the front and back surfaces 2 and 3.
It is formed so as to be substantially symmetrical with respect to it. The angles α and β between the chamfered slopes 5 and 6 and the front surface 2 and the back surface 3 and the side surface 4 are set in accordance with a transfer device used at the time of manufacturing a mask substrate. , Α, and β are both set at approximately 45 °. Further, the projection distances a and b of the chamfered slopes 5 and 6 onto the side surface 4 and the front and back surfaces 2 and 3 are also set in accordance with the transport device. In this embodiment, the projection distances are 0.6 to 0.7 mm. Is set.

The ridges 5a, 5b, 6a, 6b
Is a portion where the chamfered slopes 5 and 6 intersect the front surface 2, the back surface 3, and the side surface 4, respectively.

As shown in FIGS. 7 and 8, these ridge portions 5a and 5b are, as shown by dotted lines in the drawings,
The side surface 4 and the chamfered slope 5, and the chamfered slope 5 and the surface 2
In addition, the vicinity of the intersection line where the back surface 3 intersects with each other is removed, and the cross section is formed in a round shape so as to have a substantially arc-shaped cross section. The radius of curvature R of the arc is set in consideration of the thickness of the glass substrate body 1, the inclination angles α and β of the chamfered slopes 5 and 6, and the like, and is in a range of about 0.01 mm to 0.3 mm. It is preferable to set In this embodiment, R is set to 0.05 mm. In addition, the said ridgeline part 6
Since a and 6b are the same as the ridge portions 5a and 5b, description thereof is omitted.

The glass substrate for an electronic device of the above-described embodiment can be manufactured, for example, by the following procedure.

First, a soda lime glass having a thickness of 2.3 mm is cut into a square having a size of 127 × 127 mm, and the front and back surfaces are roughly polished to obtain a glass substrate body 1.

Next, using a well-known chamfering apparatus, chamfering is performed on the ridge portions where the front and back surfaces and the side surfaces intersect, thereby forming chamfered slopes 5 and 6.

Next, the glass substrate main body 1 is set in a polishing apparatus 7 shown in FIGS. 9 and 10, and the side surfaces including the chamfered slopes 5 and 6 are polished. This polishing device 7
Is a method in which a plurality of glass substrates 1 are set upright on a substrate fixing box 71 and fixed, and brushing is performed with a nylon brush 73 planted on a brush pedestal 72. This brushing operation is performed by rotating and reciprocating a swing arm 74 fixed to the brush pedestal 72 by a drive mechanism (not shown). At that time,
A plurality of nozzles 75 arranged around the polishing apparatus 7 eject a polishing liquid 76 in which a known polishing material is dispersed in a mixed liquid containing water or an organic solvent, and the glass substrate main body 1
Spray.

By this polishing, protruding portions where the chamfered slopes 5 and 6 intersect with the front surface 2 and the back surface 3 and the side surface 4 are selectively polished, and these portions are formed in a round shape to form the ridge portion 5a. , 5b, 6a, 6b are formed. In this polishing, the type of brush and the particle size of the abrasive to be dispersed are changed as the polishing progresses,
Performs rough polishing to precision polishing.

Then, the front and back surfaces 2 and 3 are mirror-finished by a known method, washed with a cleaning solution containing a surfactant and pure water, and dried. Thereby, a glass substrate for an electronic device is obtained.

As a result of manufacturing 100 glass substrates for an electronic device by the above-described procedure and examining peripheral scratches and the like, it was found that the surface was scratched due to contact with a holding jig during mirror polishing, or
There were no scratches or the like due to contact with the holding jig during transportation. A chromium film was formed on each surface of the glass substrates for electronic devices by a sputtering method to produce a mask substrate. Then, the number of foreign substances (fine particles) and the number of pinholes adhering to these mask substrates were examined. As a result, the number of foreign substances is less than half the number of conventional ones, and the average number of pinholes is 0.04 / cm.
² , which is half of the conventional average value of 0.08 / cm ² . Furthermore, when these mask substrates are used for semiconductor manufacturing, holding for automatic conveyance and the like can be easily performed, workability is extremely good, and no foreign matter such as a glass chip is generated with the holding, Automatic transfer and other work processes could be performed stably and smoothly without any trouble.

In the above-described embodiment, an example in which the shape of the glass substrate body 1 is substantially square has been described. However, the present invention is not limited to this. It is needless to say that the present invention can be applied to a shape. Further, it is needless to say that the side face, the chamfered slope, and the ridge portion may be mirror-finished.

[0034]

As described above in detail, according to the present invention, a flat chamfered slope is formed by chamfering a ridge portion where the front and back surfaces and side surfaces of a plate-like glass substrate intersect. It has a configuration in which a ridge line portion where the inclined surface intersects with the front and back surfaces and the side surface is formed in a round shape, whereby a relatively simple configuration may cause chipping or the like during a mask substrate manufacturing process or the like. In addition, a glass substrate for an electronic device which can be easily held during transportation is obtained.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a glass substrate for an electronic device according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram of a conventional example.

FIG. 3 is an explanatory diagram of a conventional example.

FIG. 4 is an explanatory diagram of a conventional example.

FIG. 5 is an explanatory diagram of a conventional example.

FIG. 6 is an explanatory diagram of a conventional example.

FIG. 7 is an enlarged view of a portion A in FIG. 1;

FIG. 8 is an enlarged view of a portion B in FIG. 1;

FIG. 9 is an explanatory view of a polishing step during manufacturing of one embodiment.

FIG. 10 is an explanatory view of a polishing step during manufacturing of one embodiment.

[Explanation of symbols]

1: glass substrate body, 2: front surface, 3: rear surface, 4: side surface,
5, 6 ... chamfered slopes, 5a, 5b, 6a, 6b ... ridge lines.

Claims (3)

(57) [Claims] 1. A flat chamfered slope is formed by chamfering a ridge portion where the front and back surfaces and side surfaces of a plate-like glass substrate intersect,
The radius of curvature R of the ridge portion at which the chamfered slope, the front and back surfaces, and the side surfaces intersect is 0.01 to 0.3 m.
A glass substrate for an electronic device, wherein the glass substrate is formed so as to have a diameter of m . 2. A flat chamfered slope is formed by chamfering a ridge portion where the front and back surfaces and side surfaces of the plate-like glass substrate intersect,
Brushing is performed in the region including the chamfered slope with the polishing liquid present, so that the ridge line where the chamfered slope intersects the front and back surfaces and the side surfaces has a radius of curvature R.
A glass substrate for an electronic device, wherein the glass substrate is formed so as to be 0.01 to 0.3 mm. 3. A plate-like glass substrate is cut into a predetermined size and shape, its front and back surfaces are roughly polished, and chamfering is performed on a ridge line where the front and back surfaces and side surfaces of the plate-like glass substrate intersect. To form a flat chamfered slope, and then polishing the chamfered slope and part of the side and front and back surfaces by brushing so that the chamfered slope intersects the front and back surfaces and the side surfaces, respectively. Radius of curvature R is 0.01 to
A method for producing a glass substrate for an electronic device, comprising: forming a round shape so as to have a thickness of 0.3 mm; and polishing and polishing the front and back surfaces, and then performing cleaning.