Glass article and method for manufacturing the glass article

Abstract

A method for producing a glass article, the production method having a step for sandwiching a circular carrier holding a circular glass substrate between an upper lapping plate and a lower lapping plate and rotating the carrier with respect to the upper lapping plate and lower lapping plate to thereby polish the glass substrate and obtain a glass article, and the glass substrate being positioned in the carrier so that the center Oc of the carrier is included in the region of the glass substrate and the center Og of the glass substrate is shifted with respect to the center Oc of the carrier in top view.

Description

[Technical field]

[0001] The present invention relates to a glass article and a method for manufacturing a glass article. [Background technology]

[0002] For example, thin glass articles having a thickness of about 0.1 mm are widely used in various fields. Such thin glass articles can be produced by polishing both sides of a glass substrate using a double-sided polishing machine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-138973 A Summary of the Invention [Problem to be solved by the invention]

[0004] Thin glass articles can be relatively difficult to handle, for example they can flex or warp during transportation, which can lead to cracks.

[0005] The present invention has been made in view of the above background, and has an object to provide a glass article that is relatively easy to handle and capable of significantly suppressing warping or bending, and a method for manufacturing such a glass article. [Means for solving the problem]

[0006] The present invention provides a glass article having a circular first surface, The radius R of the glass article is in the range of 50 mm to 150 mm; In the glass article, let the thickness at the center Og be to, one of the ends be the first end, the thickness at the first end be t1, and the thickness at any position X (excluding the first end and the center Og) between the first end and the center Og be tx'. When the thickness is measured from the side of the first surface of the glass article by an optical interference thickness measurement method, (a) 0.1 mm < to < 2 mm (Equation (1)), (b1) 1 < to / t1 ≤ 1.1 (Equation (2)), (c1) to > tx' > t1 (Equation (3)), and (d1) tx n ≥ (to - t1) × (n / 5) + t1 (Equation (4)) (where n is an arbitrary integer from 1 to 5, and tx n represents the thickness at the position X of R × (n / 5) from the first end toward the center Og n ), hold, With the center Og as the center, the end on the side opposite to the first end is the second end, the thickness at the second end is t2, and the thickness at any position W (excluding the second end and the center Og) between the second end and the center Og is tx''. When the thickness is measured from the side of the first surface of the glass article by the optical interference thickness measurement method, (b2) 1 < to / t2 ≤ 1.1 (Equation (5)), (c2) to > tx'' > t2 (Equation (6)), and (d2) tw n ≥ (to - t2) × (n / 5) + t2 (Equation (7)), (where n is an arbitrary integer from 1 to 5, and tw n represents the thickness at the position W of R × (n / 5) from the second end toward the center Og n ), hold, a glass article is provided.

[0007] The present invention also provides a method for producing a glass article, comprising the steps of: A process for polishing the glass substrate by sandwiching a circular carrier holding the circular glass substrate between an upper platen and a lower platen and rotating the carrier relative to the upper platen and the lower platen to obtain a glass article, The glass substrate has a top view of: The center Oc of the carrier is included in the region of the glass substrate, The center Og of the glass substrate is shifted relative to the center Oc of the carrier. In accordance with another aspect of the present invention, a method of manufacturing a semiconductor device is provided, in which the semiconductor device is disposed within the carrier such that the semiconductor device is mounted on the carrier. Effect of the Invention

[0008] The present invention can provide a glass article that is relatively easy to handle and can be significantly prevented from warping or bending. The present invention can also provide a method for producing such a glass article. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram illustrating one feature of a glass article according to one embodiment of the present invention. [Diagram 2] FIG. 1 is a diagram illustrating an example of a cross section of a glass article according to one embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing an example of another cross section of a glass article according to one embodiment of the present invention. [Figure 4] FIG. 1 is a diagram showing a schematic diagram of an example of a flow of a method for manufacturing a glass article according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a diagram showing a schematic configuration of a double-sided polishing apparatus that can be used when carrying out a method for manufacturing a glass article according to one embodiment of the present invention. [Figure 6] FIG. 2 is a top view showing a schematic example of an embodiment in which a glass substrate is arranged in a carrier. [Figure 7] 11 is a schematic top view for explaining the effect when the center of the glass substrate is shifted from the center of the carrier. FIG. [Figure 8] 13 is a graph showing the measurement results obtained in the X direction for Sample 1. [Figure 9] 13 is a graph showing the measurement results obtained in the Y direction for Sample 1. [Figure 10] 13 is a graph showing the measurement results obtained in the X direction for Sample 2. [Figure 11] 13 is a graph showing the measurement results obtained in the Y direction for Sample 2. [Figure 12] 13 is a graph showing the measurement results obtained in the X direction in Sample 3. [Figure 13] 13 is a graph showing the measurement results in the Y direction obtained in Sample 3. [Figure 14] 13 is a graph showing the measurement results obtained in the X direction for Sample 11. [Figure 15] 13 is a graph showing the measurement results in the Y direction obtained for Sample 11. [Figure 16] 13 is a graph showing the measurement results obtained in the X direction for Sample 12. [Figure 17] 13 is a graph showing the measurement results in the Y direction obtained for Sample 12. [Figure 18] 13 is a graph showing the measurement results obtained in the X direction for Sample 13. [Figure 19] 13 is a graph showing the measurement results in the Y direction obtained for Sample 13. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, one embodiment of the present invention will be described.

[0011] As described above, thin glass articles can bend or warp during transportation, and in severe cases, this can cause the article to crack.

[0012] In contrast, one embodiment of the present invention provides a glass article having a circular first surface, When the radius R of the glass article is in the range of 50 mm to 150 mm, In the glass article, let the thickness at the center Og be to, one of the ends be the first end, the thickness at the first end be t1, and the thickness at an arbitrary position X (excluding the first end and the center Og) between the first end and the center Og be tx'. When the thickness is measured from the side of the first surface of the glass article by an optical interference thickness measurement method, (a) 0.1 mm < to < 2 mm (Equation (1)), (b1) 1 < to / t1 ≤ 1.1 (Equation (2)), (c1) to > tx' > t1 (Equation (3)), and (d1) tx n ≥ (to - t1) × (n / 5) + t1 (Equation (4)) (Here, n is an arbitrary integer from 1 to 5, and tx n represents the thickness at the position X of R × (n / 5) from the first end toward the center Og n ). is satisfied, With the center Og as the center, the end on the side opposite to the first end is the second end, the thickness at the second end is t2, and the thickness at an arbitrary position W (excluding the second end and the center Og) between the second end and the center Og is tx''. When the thickness is measured from the side of the first surface of the glass article by the optical interference thickness measurement method, (b2) 1 < to / t2 ≤ 1.1 (Equation (5)), (c2) to > tx'' > t2 (Equation (6)), and (d2) tw n ≥ (to - t2) × (n / 5) + t2 (Equation (7)), (Here, n is an arbitrary integer from 1 to 5, and tw n represents the thickness at the position W of R × (n / 5) from the second end toward the center Og n ). A glass article is provided, wherein:

[0013] In the present application, the term "glass article" refers to an article obtained by polishing a glass substrate. Thus, the glass substrate is used as a material to be polished in order to manufacture the glass article.

[0014] In addition, in this application, the term "optical interference thickness measurement method" refers to a method for measuring the thickness distribution of a measurement object by the phase difference of reflected light from the front and back surfaces. Such a measurement device includes, for example, Corning-Tropel's optical interference thickness measurement device (FlatMaster200).

[0015] Here, the above condition (c1) indicates that in a cross section passing through the center Og of the glass article, the thickness of the glass article from one end (i.e., the first end) to the center Og is between the thickness t1 of the first end and the thickness to of the center Og. Similarly, the above condition (c2) indicates that in the same cross section, the thickness of the glass article from the other end (i.e., the second end) to the center Og is between the thickness t2 of the second end and the thickness to of the center Og.

[0016] Furthermore, the conditions (d1) and (d2) indicate that the thickness of the glass article in the cross section has a profile that monotonically decreases from the central portion toward each end portion.

[0017] Condition (d1) will be described in more detail below with reference to FIG.

[0018] FIG. 1 shows a schematic half of a cross section passing through a center Og of a glass article having a circular upper surface.

[0019] As shown in Fig. 1, the glass article 1 has an upper surface 2 and a radius R. The glass article 1 has a thickness to at the center Og and a thickness t1 at an end 12. Fig. 1 also shows a schematic profile of the upper surface of the glass article 1 from the end 12 to the center Og.

[0020] 1, a radius R is divided into 5 equal parts from the end 12 toward the center Og, and the respective positions are represented as X1 to X5. Note that the position X5 corresponds to the center Og.

[0021] Each position n (where n is an integer from 1 to 5) the thickness of glass article 1 is tx n In addition, when n=5, the thickness at the position X5 is tx5=to.

[0022] A straight line Q is drawn from a point Q1 on the upper surface 2 of the end portion 12 through a position Qo on the upper surface 2 of the center Og. n The intersection point of the perpendicular line at P and the line Q is n For example, the intersection of the perpendicular line and the straight line Q at position X1 is represented as P1, the intersection of the perpendicular line and the straight line Q at position X2 is represented as P2, and so on. However, point P5=position Qo.

[0023] Here, for each position X n Point P at n The height of the point P is expressed as (to-t1)×(n / 5)+t1. n The height of represents the right side of the condition (d1) above. Therefore, condition (d1) is the height of each position X obtained when the radius R is divided into five equal parts from the end 12 toward the center Og. n In the above, the thickness tx of the glass article 1 is n But at point P n means that the height is equal to or greater than the

[0024] Therefore, when the glass article 1 satisfies the condition (d1), the upper surface 2 of such glass article 1 can be said to have a profile in which the thickness decreases monotonically from the central portion towards the edge 12.

[0025] Strictly speaking, even if condition (d1) is satisfied, position X n-1 and position X nIt is considered that there is a region between the upper surface 2 and the glass article 1 where the thickness does not change monotonically. In that case, it may not be possible to say that the upper surface 2 has a profile where the thickness decreases monotonically. However, according to the inventors of the present application, in the case of a glass article 1 having a radius R in the range of 50 mm to 150 mm, if the condition (d1) is satisfied with n=5, it has been empirically understood that there is a high probability that such an upper surface 2 has a profile where the thickness decreases monotonically.

[0026] Therefore, when a glass article 1 satisfies condition (d1), the upper surface 2 of such a glass article 1 can be said to have a profile in which the thickness is thickest at the center and monotonically decreases from the center toward the end 12 (first end).

[0027] Although not shown in FIG. 1, the same can be said about the profile of the top surface from the second end to the center Og due to the condition (d2).

[0028] Hereinafter, a profile that satisfies conditions (b1) to (d1) and conditions (b2) to (d2) in a cross section passing through the center Og of the glass article (hereinafter referred to as the "maximum cross section") is specifically referred to as a "specific convex profile."

[0029] Note that the above conditions (b1) to (d1) and conditions (b2) to (d2) merely define the profile of the first surface in one "maximum cross section." In other words, the above conditions do not provide any information about the profile of the first surface in other maximum cross sections.

[0030] However, the present inventors have empirically found that in glass articles manufactured by polishing with a double-sided polishing apparatus, when one maximum cross-section satisfies the above-mentioned conditions (b1) to (d1) and conditions (b2) to (d2), the other maximum cross-sections often also satisfy conditions (b1) to (d1) and conditions (b2) to (d2).

[0031] In other words, as long as the conditions (b1) to (d1) and the conditions (b2) to (d2) are satisfied in one maximum cross section, it can be said that there is a high probability that such a glass article has a "specific convex profile" in any maximum cross section. Hereinafter, a surface having a "specific convex profile" in all maximum cross sections is also referred to as an "ideal convex surface".

[0032] As described above, the glass article according to one embodiment of the present invention has a first surface with a specific convex profile. In such a glass article, for example, the glass article can be supported from the opposite side of the first surface near the center of the glass article to significantly suppress warping or bending that may occur in the glass article.

[0033] Thus, a glass article according to an embodiment of the present invention can be relatively easily handled, even when it is relatively thin in thickness.

[0034] Furthermore, in a glass article according to one embodiment of the present invention, the effect of the first surface having a specific convex profile can easily reduce the risk of stains or unevenness caused by the cleaning liquid during or after cleaning of the glass article.

[0035] In addition, when both surfaces of a glass article are flat, stacking a plurality of such glass articles may result in the glass articles being tightly adhered to each other, making it difficult to separate them from each other. In addition, when an intermediate such as a spacer is interposed between the glass articles in order to prevent the glass articles from adhering to each other during stacking, there is a high risk that the components of the intermediate will adhere to the glass articles.

[0036] However, in the glass article according to one embodiment of the present invention, even when multiple glass articles are stacked, adhesion between the glass articles is reduced, making it easy to separate the glass articles one by one without using any intervening material.

[0037] Further, for example, when a flat glass article is chuck-fixed to various devices by a vacuum suction method or the like, both end sides of the glass article may be pulled, and the central portion may be deformed into a concave shape. However, the glass article according to an embodiment of the present invention has a first surface having a specific convex profile, and the central portion is formed thick in advance. Therefore, in the glass article according to an embodiment of the present invention, the flatness in the chuck state can be significantly increased.

[0038] Furthermore, in the glass article according to an embodiment of the present invention, for example, after the transfer of the nanoimprint process, an advantage is obtained in that it becomes easy to release the transferred resin from the imprint mold.

[0039] In addition, in the glass article according to an embodiment of the present invention, further, with the center Og as the center, a position rotated 90° from the first end is defined as the third end, the thickness at the third position is defined as t3, and the thickness at an arbitrary position Y (excluding the third end and the center Og) between the third end and the center Og is defined as ty’. When the thickness is measured from the side of the first surface by the optical interference thickness measurement method, (e1) 1 < to / t3 ≦ 1.1 (Equation (8)), (f1) to > ty’ > t3 (Equation (9)), and (g1) ty n ≧ (to - t3) × (n / 5) + t3 (Equation (10)), (where n is an arbitrary integer from 1 to 5, and ty n represents the thickness at the position Y of R × (n / 5) from the third end toward the center Og n ). It is preferable that these hold.

[0040] Furthermore, in the glass article according to an embodiment of the present invention, with the center Og as the center, an end on the side opposite to the third end is defined as the fourth end, the thickness at the fourth end is defined as t4, and the thickness at an arbitrary position V (excluding the fourth end and the center Og) between the fourth end and the center Og is defined as ty”. When measuring the thickness from the side of the first surface by the front optical interference thickness measurement method, (e2) 1 < to / t4 ≦ 1.1 (Equation (11)), (f2) to > ty” > t4 (Equation (12)), and (g2) tv n ≧ (to - t4) × (n / 5) + t4 (Equation (13)), (where n is an arbitrary integer from 1 to 5, and tv n represents the thickness at the position V of R × (n / 5) toward the center Og from the fourth end) n )(Equation (16)) is preferably satisfied.

[0041] In such a glass article, even in the maximum cross-section passing through the third end at a position rotated 90° from the first end with the center Og as the rotation axis, a first surface having a specific convex profile can be obtained.

[0042] Therefore, in this case, it becomes possible to bring the first surface of the glass article closer to an "ideal convex surface".

[0043] (Glass article according to an embodiment of the present invention) Hereinafter, with reference to FIG. 2, a glass article according to an embodiment of the present invention will be described in more detail.

[0044] FIG. 2 schematically shows a form of a cross-section of a glass article according to an embodiment of the present invention. Note that FIG. 2 shows a cross-section passing through the center Og of the glass article, that is, the "maximum cross-section". Hereinafter, the maximum cross-section shown in FIG. 2 will be referred to as the "first maximum cross-section S1".

[0045] As shown in FIG. 2, a glass article (hereinafter referred to as "the first glass article") 100 according to an embodiment of the present invention has a first surface 102 and a second surface 104. Although not clear from FIG. 2, the first surface 102 and the first glass article 100 have a substantially circular form in top view. Further, the first glass article 100 has a first end 120 and a second end 125 at positions symmetric with respect to the center Og.

[0046] Here, the first glass article 100 satisfies the aforementioned conditions (a) to (d1) and (b2) to (d2).

[0047] That is, the first glass article 100 has a thickness to at the center Og, and the thickness to is greater than 0.1 mm and less than 2 mm. The thickness to is preferably in the range of 0.2 mm to 1.1 mm.

[0048] Further, when the thickness at the first end 120 of the first glass article 100 is t1, 1 < to / t1 ≦ 1.1 is satisfied. to / t1 is preferably 1.05 or less.

[0049] Further, when the thickness at an arbitrary position X (excluding the first end 120 and the center Og) between the first end 120 and the center Og of the first glass article 100 is tx', to > tx' > t1 is satisfied.

[0050] Further, in the first glass article 100, when the thickness at the position X of R×(n / 5) from the first end 120 toward the center Og n is tx n then tx n ≧(to - t1)×(n / 5) + t1 (Equation (4)) Here, n is an arbitrary integer from 1 to 5.

[0051] Furthermore, when the thickness at the second end 125 of the first glass article 100 is t2, it satisfies 1 < to / t2 ≤ 1.1. to / t2 is preferably 1.05 or less.

[0052] Also, when the thickness at an arbitrary position W (excluding the second end 125 and the center Og) between the second end 125 and the center Og of the first glass article 100 is tx”, it satisfies to > tx” > t2.

[0053] Also, in the first glass article 100, toward the center Og from the second end 125, at the position W of R×(n / 5) n the thickness is tw n when tw n ≥ (to - t2)×(n / 5) + t2 (Equation (7)) Here, n is an arbitrary integer from 1 to 5.

[0054] Thus, the first surface 102 of the first glass article 100 has a “specific convex profile” in the first maximum cross-section S1 passing through the first end 120 and the second end 125.

[0055] Therefore, in the first glass article 100, warping or bending that may occur in the glass article during handling can be significantly suppressed. Also, thereby, the first glass article 100 can be handled relatively easily.

[0056] Here, the first glass article 100 may further satisfy the above conditions (e1) to (g1) and (e2) to (g2).

[0057] Hereinafter, with reference to FIG. 3, such features will be described.

[0058] Figure 3 schematically shows another form of the maximum cross-section of the first glass article 100. In Figure 3, a maximum cross-section (hereinafter referred to as the "second maximum cross-section") obtained when rotating 90° about the central axis Og from the position of the first maximum cross-section S1 shown in Figure 2 is shown.

[0059] As shown in Figure 3, the second maximum cross-section S2 has a third end portion 130 and a fourth end portion 135 at positions symmetric with respect to the central Og.

[0060] When the thickness at the third end portion 130 of the first glass article 100 is t3, it satisfies 1 < to / t3 ≤ 1.1. It is preferable that to / t3 is 1.05 or less.

[0061] Also, when the thickness at an arbitrary position Y (excluding the third end portion 130 and the central Og) between the third end portion 130 and the central Og of the first glass article 100 is ty’, it satisfies to > ty’ > t1.

[0062] Also, in the first glass article 100, when the thickness at the position Y of R×(n / 5) from the third end portion 130 toward the central Og n is ty n then ty n ≥ (to - t3)×(n / 5) + t3 (Equation 10) Here, n is an arbitrary integer from 1 to 5.

[0063] Furthermore, when the thickness at the fourth end portion 135 of the first glass article 100 is t4, it satisfies 1 < to / t4 ≤ 1.1. It is preferable that to / t4 is 1.05 or less.

[0064] Also, when the thickness at an arbitrary position W (excluding the fourth end portion 135 and the central Og) between the fourth end portion 135 and the central Og of the first glass article 100 is ty”, it satisfies to > ty” > t4.

[0065] In addition, in the first glass article 100, from the fourth end 135 toward the center Og, a position W n The thickness at tv n When TV n ≧(to-t4)×(n / 5)+t4 (13) Here, n is an arbitrary integer from 1 to 5.

[0066] In this manner, the first surface 102 of the first glass article 100 may also have a “particular convex profile” at the second maximum cross section S2 passing through the third end 130 and the fourth end 135.

[0067] In this case, it is possible to make the first surface 102 of the first glass article 100 closer to an "ideal convex surface."

[0068] Other features of the glass article according to an embodiment of the present invention Next, other features of the glass article according to one embodiment of the present invention will be described.

[0069] A glass article according to an embodiment of the invention may be composed of any glass, for example, soda-lime glass, borosilicate glass, or alkali-free glass.

[0070] The glass may be chemically or physically strengthened.

[0071] Furthermore, the glass for the glass article preferably has a refractive index of 1.6 or more, more preferably 1.7 or more, and even more preferably 1.8 or more.

[0072] Furthermore, the glass for the glass article preferably has a surface roughness (Ra) of 1 nm or less, and more preferably 0.5 nm or less.

[0073] A glass article according to one embodiment of the present invention has a circular shape in top view, with a radius R in the range of 50 mm to 150 mm. The radius R is preferably in the range of 75 mm to 150 mm.

[0074] In the example shown in FIGS. 2 and 3, the second surface 104 of the first glass article 100 is substantially flat.

[0075] However, this is merely an example, and in a glass article according to an embodiment of the present invention, the form of the second surface 104 is not particularly limited. For example, the second surface 104 may have at least one maximum cross section having a "specific convex profile" similar to the first surface 102. In particular, the second surface 104 may be an "ideal convex surface."

[0076] (Method of manufacturing a glass article according to one embodiment of the present invention) Next, an example of a method for producing a glass article according to an embodiment of the present invention will be described with reference to FIGS.

[0077] FIG. 4 shows a schematic flow of a method for producing a glass article according to one embodiment of the present invention (hereinafter referred to as a "first production method").

[0078] As shown in FIG. 4, the first manufacturing method includes the following steps: (1) a step of placing one circular glass substrate on one circular carrier, the glass substrate being disposed in the carrier such that, in a top view, a center Oc of the carrier is included in the area of ​​the glass substrate and a center Og of the glass substrate is shifted from the center Oc of the carrier (step S110); (2) pressing the carrier with an upper platen and a lower platen (step S120); (3) rotating the carrier relative to an upper platen and a lower platen to polish the glass substrate (step S130); has.

[0079] FIG. 5 shows a schematic configuration of a double-sided polishing machine that can be used when carrying out the first manufacturing method.

[0080] 5, the double-sided polisher 201 has a sun gear 210, an internal gear 220, an upper surface plate 230, and a lower surface plate 250. The sun gear 210 and the internal gear 220 are formed so that their respective rotation axes coincide with the center of the double-sided polisher 201. In addition, the sun gear 210 is disposed at the center of the double-sided polisher 201 when viewed from above, and the internal gear 220 is disposed on the outer periphery side of the double-sided polisher 201.

[0081] The upper platen 230 and the lower platen 250 are disposed to face each other and can rotate in opposite directions or in the same direction. The upper platen 230 has a polishing pad (not shown) on its lower surface, i.e., the side facing the lower platen 250. Similarly, the lower platen 250 has a polishing pad (not shown) on its upper surface, i.e., the side facing the upper platen 230.

[0082] A carrier 280 supporting a glass substrate 290 to be polished is placed on the lower surface plate 250. In the example of Fig. 1, a plurality of carriers 280 are placed on the lower surface plate 250. However, this is merely an example, and the number of carriers 280 placed on the lower surface plate 250 is not particularly limited.

[0083] The carrier 280 has a gear 282 on its outer periphery that is configured to engage with the sun gear 210 and the internal gear 220 .

[0084] Hereinafter, each step in the first manufacturing method will be described with reference to FIGS.

[0085] (Step S110) First, a circular carrier 280 and a circular glass substrate 290 are prepared. The glass substrate 290 is held within the carrier 280.

[0086] The glass substrate 290 has an upper surface and a lower surface.

[0087] The diameter (inner diameter) Lc of the carrier 280 is not particularly limited, but may be in the range of 110 mm to 600 mm, for example. However, it is preferable that the diameter Lc is in the range of 1.1 to 2 times the diameter Lg.

[0088] The thickness of the glass substrate 290 is not particularly limited, but may be in the range of 0.1 mm to 2 mm, for example.

[0089] Each carrier 280 supports one glass substrate 290 .

[0090] FIG. 6 is a top view showing a schematic example of an embodiment in which a glass substrate 290 is arranged in a carrier 280. As shown in FIG.

[0091] 6, the glass substrate 290 is disposed in the carrier 280 such that the center Oc of the carrier 280 is included in the area of ​​the glass substrate 290 when viewed from above. Moreover, the glass substrate 290 is disposed in the carrier 280 such that the center Og of the glass substrate 290 is shifted from the center Oc of the carrier 280 when viewed from above.

[0092] In top view, the distance d between the center Og of the glass substrate 290 and the center Oc of the carrier 280 is in the range of, for example, 0.05×Lg to 0.5×Lg. The distance d is preferably 0.1×Lg or more and 0.25×Lg or less.

[0093] (Process S120) Next, each carrier 280 is placed on the lower surface plate 250. Furthermore, the upper surface plate 230 is placed on each carrier 280, and each carrier 280 is sandwiched between the upper surface plate 230 and the lower surface plate 250.

[0094] As a result, the upper and lower surfaces of each glass substrate 290 are brought into contact with the upper surface plate 230 and the lower surface plate 250, respectively.

[0095] (Step S130) Next, the sun gear 210 and the internal gear 220 are rotated at a predetermined rotation ratio, thereby rotating the carrier 280 on its axis and revolving the carrier 280 along the internal gear 220 (planetary drive). Furthermore, the upper surface plate 230 and the lower surface plate 250 are rotated.

[0096] As a result, the upper and lower surfaces of each glass substrate 290 are polished simultaneously by the upper surface plate 230 and the lower surface plate 250 .

[0097] During polishing of each glass substrate 290, a polishing liquid may be supplied to the glass substrate 290 from the side of the upper surface plate 230 and / or the lower surface plate 250, if necessary.

[0098] By using such double-sided polishing apparatus 201, the upper and lower surfaces of glass substrate 290 can be polished simultaneously.

[0099] Here, the glass substrate 290 is placed in a state where the center Og is "eccentric" by a distance d from the center Oc of the carrier 280. In this case, the glass substrate 290 is polished by a relatively smaller amount toward the center Og.

[0100] The reason for this will be explained below with reference to FIG.

[0101] As described above, in the double-sided polishing apparatus 201, the carrier 280 is rotated on its axis while revolving around the internal gear 220. Therefore, during the polishing process, the glass substrate 290 held by the carrier 280 moves so as to revolve around the periphery of the internal gear 220 while rotating on its axis.

[0102] FIG. 7 is a top view showing typically different positional states (290A to 290C) of the glass substrate 290 during operation of the double-sided polishing apparatus 201 shown in FIG.

[0103] For clarity, the upper platen 230 is not shown in Fig. 7. Also, in Fig. 7, the sun gear 210 and the internal gear 220 are shown only diagrammatically so as to clarify their positional relationship with the glass substrate 290.

[0104] That is, the sun gear 210 is shown having an outer peripheral edge 212 that is shown generally to clarify the closest position of the glass substrate 290 to the sun gear 210. Similarly, the internal gear 220 is shown having an inner peripheral edge 222 that is shown generally to clarify the closest position of the glass substrate 290 to the internal gear 220.

[0105] In other words, the outer peripheral end 212 of the sun gear 210 indicates the imaginary limit line when the glass substrate 290 is positioned at its innermost position relative to the lower base plate 250, and the inner peripheral end 222 of the internal gear 220 indicates the imaginary limit line of the glass substrate 290 when the glass substrate 290 is positioned at its outermost position relative to the lower base plate 250.

[0106] As shown in FIG. 7, the glass substrate 290 that rotates and revolves during the polishing process can take the following three positional aspects with respect to the lower surface plate 250: (i) the outermost position; i.e., a first position where the outer peripheral end of the glass substrate 290 contacts the inner peripheral end 222 of the internal gear 220 (the glass substrate 290 in this position is represented as “glass substrate 290A”); (ii) an innermost position; i.e., a second position where the outer peripheral edge of the glass substrate 290 contacts the outer peripheral end 212 of the sun gear 210 (the glass substrate 290 in this position is represented as “glass substrate 290B”); and (iii) Intermediate position; that is, a third position between (i) and (ii) (the glass substrate 290 in this position is represented as “glass substrate 290C”) It is.

[0107] As a result, the center Og of the glass substrate 290 is located only in the shaded region 298 in Fig. 7. The dashed line passing through the center of the region 298 indicates the locus of the center Oc of the carrier 280.

[0108] Generally, the polishing amount of the central region is smaller than that of the peripheral region because the polishing agent is less likely to be supplied to the central region of the glass substrate 290 than to the peripheral region. Therefore, the polishing amount of the glass substrate 290 is relatively smaller in the central region including the center Og.

[0109] As a result, the first manufacturing method makes it relatively easy to manufacture a glass article in which at least one of the upper surface and the lower surface has a "specific convex profile."

[0110] Here, the rotation (spin) direction of the carrier 280 may be opposite to the rotation direction of the lower platen 250. In this case, the relative rotation speed of the glass substrate 290 with respect to the lower platen 250 can be increased. Therefore, a glass article whose upper or lower surface has a "specific convex profile" can be manufactured more efficiently.

[0111] The glass article produced by the first production method has a maximum thickness in the range of, for example, 0.1 mm to 2 mm. The glass article produced by the first production method may have a diameter Lg in the range of 100 mm to 300 mm.

[0112] (Application) The glass article according to an embodiment of the present invention may be used, for example, as an optical member. The glass article according to an embodiment of the present invention may be used, for example, as a light guide plate for a head mounted display. EXAMPLES

[0113] Examples of the present invention will now be described.

[0114] (Example 1) Using a double-sided polishing machine, both sides of a circular glass substrate having a diameter of 150 mm were polished to produce a glass article.

[0115] A circular carrier with a diameter Lc of 228.6 mm was used as the carrier. The glass substrate was placed in the carrier so that the distance d between the center Og of the glass substrate and the center Oc of the carrier was 25 mm. Therefore, d / Lg ≈ 0.17. In addition, when viewed from above, the center Oc of the carrier was placed within the area of ​​the glass substrate.

[0116] The pressure applied by the upper and lower plates is 40g / cm 2 The polishing time was 40 minutes. The rotation speed of the upper platen was 8 rpm, and the rotation speed of the lower platen was 24 rpm. The rotation speed of the carrier was 8 rpm. The upper platen and the carrier were rotated in the opposite direction to the rotation direction of the lower platen.

[0117] The thickness of one end (first end) of the obtained glass article (hereinafter referred to as "Sample 1") was approximately 325 μm.

[0118] (Example 2) A glass article was manufactured in the same manner as in Example 1. However, in this Example 2, the distance d was set to 20 mm. Therefore, d / Lg was approximately 0.13. The other conditions were the same as in Example 1. The obtained glass article is referred to as "Sample 2."

[0119] (Example 3) A glass article was manufactured in the same manner as in Example 1. However, in this Example 3, the distance d was set to 10 mm. Therefore, d / Lg was approximately 0.067. The other conditions were the same as in Example 1. The obtained glass article is referred to as "Sample 3."

[0120] (Example 11) Using a double-sided polishing machine, both sides of a circular glass substrate having a diameter of 150 mm were polished to produce a glass article.

[0121] A circular carrier with a diameter Lc of 406.4 mm was used as the carrier. The glass substrate was placed in the carrier so that the distance d between the center Og of the glass substrate and the center Oc of the carrier was 110 mm. Therefore, when viewed from above, the center Oc of the carrier was located at a position outside the area of ​​the glass substrate.

[0122] The pressure applied by the upper and lower plates is 40g / cm 2 The polishing time was 60 minutes. The rotation speed of the upper platen was 6 rpm, and the rotation speed of the lower platen was 18 rpm. The rotation speed of the carrier was 6 rpm. The upper platen and the carrier were rotated in the opposite direction to the rotation direction of the lower platen.

[0123] The thickness of one end (first end) of the obtained glass article was about 325 μm.

[0124] The resulting glass article is referred to as "Sample 11."

[0125] (Example 12) A glass article was produced in the same manner as in Example 11. However, in this Example 12, the polishing time was 90 minutes. The other conditions were the same as in Example 11. The obtained glass article is referred to as "Sample 12."

[0126] (Example 13) A glass article was produced in the same manner as in Example 11. However, in this Example 13, the polishing time was 150 minutes. The other conditions were the same as in Example 11. The obtained glass article is referred to as "Sample 13."

[0127] (evaluation) The thickness profile of each sample was measured by optical interference thickness measurement using a Corning-Tropel measuring device (FlatMaster200).

[0128] For each sample, a thickness profile measurement (referred to as "X-direction measurement") was performed over a region from a first end, passing through the center Og of the sample, to the opposite end, where the first end was an arbitrarily selected end.

[0129] In addition, a thickness profile measurement (referred to as "Y-direction measurement") was performed over the area from the third end, which is located 90 degrees rotated from the first end with the center Og as the rotation axis, through the center Og of the sample to the opposite end.

[0130] 8 and 9 show the X-direction and Y-direction measurement results obtained for Sample 1, respectively. FIGS. 10 and 11 show the X-direction and Y-direction measurement results obtained for Sample 2, respectively. FIGS. 12 and 13 show the X-direction and Y-direction measurement results obtained for Sample 3, respectively. FIGS. 14 and 15 show the X-direction and Y-direction measurement results obtained for Sample 11, respectively. FIGS. 16 and 17 show the X-direction and Y-direction measurement results obtained for Sample 12, respectively. Furthermore, FIGS. 18 and 19 show the X-direction and Y-direction measurement results obtained for Sample 13, respectively.

[0131] In these figures, the horizontal axis represents the position of the sample (unit: mm), the origin 0 is the center Og of the sample, and the vertical axis represents the height displacement (unit: μm) at each position based on the minimum thickness of the sample.

[0132] From these results, it is found that the central axis of the sample is shifted from the position where the thickness is maximum in Sample 11 and Sample 13. Also, it was found that Sample 12 does not have a profile in which the thickness decreases monotonically from the center to the third end, as shown in Fig. 17.

[0133] In contrast, in Samples 1 to 3, the central axis of the sample roughly coincides with the position where the thickness is maximum, and it was found that in both the X-direction and Y-direction measurements, a profile was obtained in which the thickness monotonically decreased from the center Og to the end.

[0134] In this way, it was confirmed that in Samples 1 to 3, the "specific convex profile" was obtained on the surface in both the "maximum cross section" in the X direction and the "maximum cross section" in the Y direction.

[0135] This application claims priority based on Japanese Patent Application No. 2020-076645, filed on April 23, 2020, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0136] 1. Glass items 2 Top side 12 End 100 First glass article 102 First Surface 104 Second Surface 120 First end 125 Second End 130 Third End 135 Fourth End 201 Double-sided polishing machine 210 Sun Gear 212 (of sun gear) outer periphery 220 Internal Gear 222 (of internal gear) inner peripheral end 230 Upper surface plate 250 Lower surface plate 280 Career 282 Gear 290 Glass Substrate 298 areas S1 First largest section S2 Second largest cross section

Claims

1. 1. A glass article having a circular first surface, The radius R of the glass article is in the range of 50 mm to 150 mm; In the glass article, the thickness at the center Og is to, a certain end is a first end, the thickness at the first end is t1, and the thickness at any position X between the first end and the center Og (excluding the first end and the center Og) is tx'; When the thickness of the glass article is measured from the first surface side by an optical interference thickness measurement method, (a) 0.1mm<to<2mm (1) formula, (b1) 1<to / t1≦1.1 (2) formula, (c1) to>tx'>t1 (3), and (d1) tx ｎ ≧(t−t1)×(n / 5)+t1 (4) (wherein n is an integer from 1 to 5, and tx ｎ is a position X of R×(n / 5) from the first end toward the center Og. ｎ (represents the thickness at is established, The end opposite the first end with respect to the center Og is defined as a second end, the thickness at the second end is defined as t2, and the thickness at any position W between the second end and the center Og (excluding the second end and the center Og) is defined as tx'', When the thickness of the glass article is measured from the first surface side by the optical interference thickness measurement method, (b2) 1<to / t2≦1.1 (5) formula, (c2) to>tx">t2 (6), and (d2)tw ｎ ≧(tot2)×(n / 5)+t2 (7) Formula, (wherein n is an integer from 1 to 5, and tw ｎ is a position W of R×(n / 5) from the second end toward the center Og. ｎ (represents the thickness at A glass article according to the present invention.

2. Furthermore, a position rotated 90° from the first end around the center Og is defined as a third end, the thickness at the third end is defined as t3, and the thickness at any position Y between the third end and the center Og (excluding the third end and the center Og) is defined as ty'; When the thickness of the glass article is measured from the first surface side by the optical interference thickness measurement method, (e1) 1<t / t3≦1.1 (8) (f1) to>ty'>t3 (9), and (g1) ty ｎ ≥ (to - t3) × (n / 5) + t3 (Equation (10)) (wherein n is an integer from 1 to 5, and ty ｎ is a position Y of R×(n / 5) from the third end toward the center Og. ｎ (represents the thickness at is established, The end opposite the third end with respect to the center Og is defined as a fourth end, the thickness at the fourth end is defined as t4, and the thickness at any position V between the fourth end and the center Og (excluding the fourth end and the center Og) is defined as ty'', When the thickness of the glass article is measured from the first surface side by the optical interference thickness measurement method, (e2) 1<to / t4≦1.1 (11) formula, (f2) to>ty">t4 (12), and (g2)tv ｎ ≥(to - t4)×(n / 5)+t4 (Equation 13) (wherein n is an integer from 1 to 5, and tv ｎ is a position V of R×(n / 5) from the fourth end toward the center Og. ｎ (represents the thickness at The glass article according to claim 1 ,

3. A method for producing the glass article according to claim 1, comprising the steps of: A process for polishing the glass substrate by sandwiching a circular carrier holding the circular glass substrate between an upper platen and a lower platen and rotating the carrier relative to the upper platen and the lower platen to obtain a glass article, The glass substrate has a top view of: The center Oc of the carrier is included in the area of ​​the glass substrate, The center Og of the glass substrate is shifted relative to the center Oc of the carrier. The manufacturing method of the present invention further comprises the steps of:

4. When the diameter of the glass substrate is Lg, The manufacturing method according to claim 3 , wherein a distance d between the center Oc and the center Og in a top view of the glass substrate satisfies 0.05×Lg≦d≦0.5×Lg.

5. The manufacturing method according to claim 4 , wherein the distance d is equal to or greater than 0.1×Lg.

6. The method according to claim 4 or 5, wherein the distance d is 0.25×Lg or less.

7. The method according to any one of claims 3 to 6, wherein the glass article has a maximum thickness in the range of 0.1 mm to 2 mm.

8. The method according to any one of claims 3 to 7, wherein the glass article has a radius in the range of 50 mm to 150 mm.

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