WO2007073072A1

WO2007073072A1 - Mask apparatus for divided deposition of substrate and patterning method using the same

Info

Publication number: WO2007073072A1
Application number: PCT/KR2006/005536
Authority: WO
Inventors: Taek-Sang Kang; Kyoung-Ook Lee; Dae-Soo Lee; Seung-Han Kim
Original assignee: Doosan Mecatec Co., Ltd.
Priority date: 2005-12-19
Filing date: 2006-12-18
Publication date: 2007-06-28
Also published as: TWI331410B; TW200729564A

Abstract

The present invention relates to a mask apparatus for divided deposition of a substrate and a patterning method using the same. With a mask apparatus for forming a pattern on a substrate according to the present invention, the substrate is imaginarily divided into two or more regions and the regions are sequentially patterned. Thus, there is an advantage in that technical and economical problems in manufacturing a large-sized mask can be avoided. In addition, since welding burrs do not come into contact with the substrate when the substrate is in close contact with the mask, the present invention has advantages in that it is possible to prevent damage to the substrate and to allow the substrate to be in closer contact with the mask.

Description

MASK APPARATUS FOR DIVIDED DEPOSITION OF SUBSTRATE AND PATTERNING METHOD USING THE SAME

Technical Field

[1] The present invention relates to a mask apparatus for divided deposition of a substrate and a patterning method using the same, and more particularly, to a mask apparatus for divided deposition of a substrate and a patterning method using the same, wherein the substrate is imaginarily divided into at least two regions and the regions of the substrate are sequentially patterned. Background Art

[2] Recently, with rapid development of information telecommunication technology and expansion of the market thereof, flat panel displays come into spotlight as a popular display. The flat panel displays typically include a liquid crystal display, a plasma display panel, an organic light emitting device, and the like.

[3] Among them, the organic light emitting device comes into spotlight as the next generation display since it has remarkable advantages of fast response time, low power consumption, light weight, ultra-slimness without an additional backlight, and high luminance as compared with a conventional liquid crystal display.

[4] Such an organic light emitting device is a self-luminous device in which an anode film, an organic thin film and a cathode film are sequentially coated on a substrate so that light can be emitted due to a proper energy difference generated in the organic thin film by applying a voltage between the anode and cathode films. That is, excitation energy remaining upon recombination of injected electrons and holes is converted into light to be emitted. At this time, since the wavelength of generated light can be adjusted according to the amount of organic dopants, it is possible to implement a full color display.

[5] Meanwhile, in order to achieve a full color display using the organic light emitting device, there is a need for methods of effectively forming R (red), G (green) and B (blue) light-emitting layers. As for the methods studied currently, there are about five methods: a side-by-side method in which respective light-emitting layers are utilized, a method in which color filters are provided on a white light-emitting layer, a method in which a color change material is utilized, a method in which an optical mechanism of a color spectrum is used, a selective generation method using sub-pixels, and the like.

[6] As shown in Fig. 1, in a conventional process of forming a pattern in an organic light emitting device, a substrate S is introduced into and fixed in a chamber. In this state, organic materials exhibiting red (R), green (G) and blue (B) are evaporated so that the vapor of the organic materials are deposited on the substrate 10 through a mask 100.

[7] In the meantime, large-sized substrates are recently required depending on industrial demands. In this case, a large-sized mask corresponding to a large-sized substrate is required to pattern the large-sized substrate at a time from one end to the other end thereof in the same manner as the conventional methods described above.

[8] In order to manufacture a large-sized mask corresponding to a large-sized substrate, however, high costs and a great deal of time are required, and at the same time, it is very difficult to handle the large-sized mask, resulting in inefficiency of the process. Accordingly, there are many problems in patterning the substrate using the large-sized mask.

[9] Meanwhile, a conventional mask apparatus has an edge to be fixed to a frame by means of welding. At this time, burrs are inevitably formed on welding points. Accordingly, when a substrate is brought into close contact with the mask, the welding burrs first come into contact with the substrate. If the substrate is then brought into closer contact with the mask in such a state, the substrate or a thin film formed thereon is damaged. In addition, there is a problem in that close contact between the substrate and the mask is prohibited by the welding burrs. Disclosure of Invention

Technical Problem

[10] The present invention is conceived to solve the aforementioned problems. An object of the present invention is to provide to a mask apparatus for divided deposition of a substrate and a patterning method using the same, wherein the substrate is imaginarily divided into at least two regions and the regions of the substrate are sequentially patterned.

[11] Another object of the present invention is to provide a mask apparatus for divided deposition of a substrate, wherein damage to the substrate that may occur due to contact of welding burrs with the substrate can be prevented and a mask can be brought into closer contact with the substrate. Technical Solution

[12] In order to achieve these objects, a mask apparatus for divided deposition of a substrate to form a pattern on the substrate according to the present invention comprises at least one mask having a patterned surface for use in forming a pattern in any one of imaginarily divided, two or more regions of the substrate.

[13] The mask may comprise a first mask having a patterned surface for use in forming a pattern in any one of the imaginarily divided, two or more regions of the substrate; and a second mask having a patterned surface for use in forming a pattern on the other region of the substrate.

[14] In the mask apparatus of the present invention, the patterned surface of the first mask may be identical with or different from that of the second mask in area.

[15] The first and second masks may be mounted in one chamber while being stacked sequentially. In this case, a transfer means may be provided for horizontally transferring the first and second masks. Alternatively, the first and second masks may be mounted respectively in separate chambers.

[16] Further, patterns may be formed by imaginarily dividing the substrate into two regions: upper and lower regions or left and right regions. In a case where the substrate is divided into the upper and lower regions, the first and second masks are used for forming the patterns on the upper and lower regions, respectively. In a case where the substrate is divided into the left and right regions, the first and second masks are used for forming the patterns on the left and right regions, respectively.

[17] In addition, the first and second masks may be provided with alignment means such as marks for allowing the masks to be aligned with the substrate.

[18] A method of divisionally forming patterns on a substrate according to the present invention comprises the steps of: 1) preparing first and second masks each of which has a patterned surface for use in forming a pattern in one of imaginarily divided, two regions of the substrate; 2) bringing the first mask into close contact with the substrate to form a pattern on one of the regions of the substrate; and 3) bringing the second mask into close contact with the substrate to form a pattern on the other region of the substrate. Steps 2) and 3) may be performed in an identical chamber or different separate chambers.

[19] A method of divisionally forming a predetermined pattern on a substrate to repeatedly form the pattern on the substrate according to the present invention comprises the steps of: 1) preparing a mask having a patterned surface corresponding to the predetermined pattern; 2) brining the mask into contact with one of regions of the substrate to form the predetermined pattern on the region; and 3) transferring the mask and brining the mask into contact with another region of the substrate to form the predetermined pattern on the other region.

[20] Step 3) may be carried out after the mask is transferred horizontally or rotated.

[21] The first or second mask may be welded to a frame, and welding points at which the mask is welded to the frame may be formed below the patterned surface.

[22] To this end, an upper surface of the frame may be formed with a taper or curved section such that an outer side of the upper surface of the frame is lower than an inner side thereof.

[23] The welding points may be formed on an outer wall of the frame. Brief Description of the Drawings

[24] The above and other objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:

[25] Fig. 1 is a view illustrating a conventional patterning process for a small-sized substrate;

[26] Fig. 2 is a view illustrating a patterning process for a large-sized substrate according to a first embodiment of the present invention;

[27] Figs. 3a and 3b are views showing the substrate on which patterns are formed by the process illustrated in Fig. 2;

[28] Fig. 4 is a view illustrating a patterning process for a large-sized substrate according to a second embodiment of the present invention;

[29] Figs. 5a and 5b are views showing the substrate on which patterns are formed by the process illustrated in Fig. 4; and

[30] Figs. 6 to 9 are sectional views of substrates and masks according to other embodiments of the present invention. Mode for the Invention

[31] Hereinafter, the configuration and operation of the present invention will be described in detail with reference to the accompanying drawings.

[32] Referring to Fig. 2, a mask apparatus according to an embodiment of the present invention comprises a first mask 10 and a second mask 20 which are separately f ormed.

[33] The first mask 10 includes a patterned surface 11 for use in patterning a left half region Sl of a substrate S, which is imaginarily divided into two equal regions, and a non-patterned surface 12. The non-patterned surface 12 has no pattern formed thereon and serves as an area in which an alignment mark 10b is formed or which is welded to a frame (not shown).

[34] The second mask 20 includes a patterned surface 21 for use in patterning a right half region S2 of the substrate S and a non-patterned surface 22.

[35] In addition, in order to align the substrate S, the first mask 10 and the second mask

20 with one another, alignment marks a and b are formed at an upper left end and a lower right end with respect to a boundary of the substrate, respectively. Alignment marks 10a and 20a and alignment marks 10b and 20b are formed at upper left ends and lower right ends with respect to boundaries between the patterned surfaces 11 and 21 and the non-patterned surfaces 12 and 22 of the first and second masks 10 and 20, respectively.

[36] The operation of this embodiment will be described below with reference to Figs. 2, 3a and 3b. In a state where the large-sized substrate S is introduced into and fixed in a chamber, the first mask 10 is transferred toward below the left half region Sl of the substrate S and then brought into contact with a lower surface of the substrate in the left half region. Further, in order to accurately align the substrate S with the first mask 10, the alignment mark a formed at the upper left end with respect to the boundary of the substrate S is matched with the alignment mark 10a formed at the upper left end with respect to the boundary of the first mask 10. Similarly, the alignment mark b formed at the lower right end with respect to the boundary of the substrate S is matched with the alignment mark 10b formed at the lower right end with respect to the boundary of the first mask 10. In this state, an organic material is evaporated and forms a pattern in the left half region S 1 of the substrate S through the first mask 10 as shown in Fig. 3a.

[37] After the pattern is formed in the left half region Sl of the substrate as such, the first mask 10 is removed by a transfer robot (not shown).

[38] Thereafter, the second mask 20 is transferred toward below the right half region S2 of the substrate S by the transfer robot (not shown) and then brought into contact with a lower surface of the substrate in the right half region. Further, in order to accurately align the substrate S with the second mask 20, the alignment mark a formed at the upper left end with respect to the boundary of the substrate S is matched with the alignment mark 20a formed at the upper left end with respect to the boundary of the second mask 20. Similarly, the alignment mark b formed at the lower right end with respect to the boundary of the substrate S is matched with the alignment mark 20b formed at the lower right end with respect to the boundary of the second mask 20. In this state, an organic material is evaporated and forms a pattern in the right half region S2 of the substrate S through the second mask 20 as shown in Fig. 3b.

[39] If the patterns to be formed in the left half region S 1 and right half region S2 of the substrate S are identical with each other, the patterned surfaces of the first and second masks are identical with each other. Accordingly, in this case, it is not necessary to separately manufacture the two masks in duplicate and only one of the two masks can be manufactured. A method of forming a pattern on the substrate using only one mask will be described below. First, the mask is brought into contact with the lower surface of the substrate S in the left half region S 1 and the pattern is then formed thereon. Subsequently, the mask is transferred horizontally toward below the right half region S2 of the substrate and then brought into contact with the lower surface of the substrate S in the right half region S2, and the pattern is formed on the right half region, thereby forming the pattern on the entire surface of the substrate.

[40] In a case where a pattern to be formed on the left half region S 1 of the substrate S and a pattern to be formed on the right half region S2 are symmetrical with each other, the mask is brought into close contact with the lower surface of the substrate in the left half region Sl to form the pattern. Subsequently, the mask is rotated by 180 degrees and then brought into close contact with the lower surface of the substrate in the right half region S2 to form the pattern, thereby forming the patterns on the entire surface of the substrate.

[41] Fig. 4 is a view showing another embodiment according to the present invention. A mask apparatus shown in Fig. 4 can be used for patterning a substrate by imaginarily dividing the substrate unequally rather than equally into a left region S3 and a right region S4.

[42] More specifically, a patterned surface 31 of a first mask 30 is different from a patterned surface 41 of a second mask 40 in area. Except the difference in area, the configurations of non-patterned surfaces 32 and 42 and alignment marks 30a, 30b, 40a and 40b are the same as those of the previous embodiment. Further, this embodiment is identical with the previous embodiment in that the masks are horizontally transferred by the transfer robot.

[43] The operation of this embodiment will be described below with reference to Figs. 4,

5a and 5b.

[44] In a state where a large-sized substrate S is introduced into and fixed in a chamber, the first mask 30 is transferred toward below the left region S3 of the substrate and then brought into close contact with a lower surface of the substrate in the left region. Further, in order to accurately align the substrate S with the first mask 30, an alignment mark a formed at an upper left end with respect to a boundary of the substrate S is matched with an alignment mark 30a formed at an upper left end with respect to a boundary of the first mask. Similarly, an alignment mark b formed at a lower right end with respect to the boundary of the substrate S is matched with an alignment mark 30b formed at a lower right end with respect to the boundary of the first mask 30. In this state, an organic material is evaporated and forms a pattern in the left region S3 of the substrate S through the first mask 30 as shown in Fig. 5a.

[45] After the pattern is formed on the left region S3 of the substrate as above, the first mask 30 is removed by a transfer robot (not shown).

[46] Thereafter, the second mask 40 is transferred by the transfer robot (not shown) toward below the right region S4 of the substrate and is then brought into close contact with a lower surface of the substrate in the right region. Further, in order to accurately align the substrate S with the second mask 30, the alignment mark a formed at the upper left end with respect to the boundary of the substrate S is matched with an alignment mark 40a formed at an upper left end with respect to a boundary of the second mask. Similarly, the alignment mark b formed at the lower right end with respect to the boundary of the substrate S is matched with an alignment mark 40b formed at a lower right end with respect to the boundary of the second mask. In this state, an organic material is evaporated and forms a pattern in the right region S4 of the substrate S through the second mask 40 as shown in Fig. 5b.

[47] Since the foregoing is merely the embodiments according to the present invention, the present invention is not limited thereto and it will be apparent that various modifications and changes can be made thereto. For example, the mask apparatus according to the present invention may comprise three or more masks. In addition, although the mask apparatus comprises the first and second masks for use in sequentially patterning the divided left and right regions of the substrate in the above embodiment, the first and second masks may otherwise have patterned surfaces formed such that the first mask can pattern an upper region of the substrate and the second mask can pattern a lower region thereof.

[48] Further, although the mask apparatus of the above embodiment is constructed such that the first and second masks are provided in the same chamber and then horizontally transferred according to the process sequence to form patterns on the substrate, the first mask and the second mask may otherwise be provided in separate chambers. That is, the left region of the substrate is patterned in a first chamber in which the first mask is provided, and this substrate is then introduced into a second chamber in which the second mask is provided to pattern the right region of the substrate, so that the entire surface of the substrate can be patterned.

[49] Referring to Fig. 6, the first mask 10 is installed in the chamber in a state where it is welded to a frame 14. An upper surface of the frame 14 comprises a horizontal section Ml adjacent to an opening of the frame and a taper section M2 inclined downward and outward from the horizontal section Ml.

[50] The first mask is fixed through welding to several points on the taper section M2 of the frame in a state where the patterned surface 11 and the non-patterned surface 12 of the first mask 10 are located in the opening of the frame and a tensile force is applied to the first mask such that an edge of the first mask comes into close contact with the horizontal section Ml. Thus, it can be seen that the welding points 15 are formed below the patterned surface 11 (hl>h2).

[51] The operation of this embodiment will be described below with reference to Fig. 6.

Since the first mask 10 is fixed to the frame such that the welding points 15 are formed below the patterned surface 11 as described above, the welding points 15, in particular, welding burrs do not come into contact with the substrate S when the substrate S is in close contact with the first mask 10. Accordingly, damage to the substrate S caused by the welding burrs is prevented and the substrate S can be in close contact with the mask 10 without any influence of the welding burs.

[52] Referring to Fig. 7, the formation of the horizontal section Ml on an inner side of an upper surface of the frame 14 is identical with that of the embodiment shown in Fig. 6. However, there is a difference in that the frame has a curved section M3 having a radius of curvature r and extending downward and outward from an end of the horizontal section Ml.

[53] The mask is fixed through welding to several points on the curved section M3 of the frame in a state where a tensile force is applied to the mask such that an edge 13 of the mask 10 comes into close contact with the horizontal section Ml of the frame. Even in this embodiment, the welding points 15 are formed below the patterned surface 11. Since the welding points 15, in particular, welding burrs do not come into contact with the substrate S when the substrate S is in close contact with the mask 10, damage to the substrate S caused by the welding burrs is prevented and the substrate S can be in close contact with the mask 10 without any influence of the welding burs.

[54] Referring to Fig. 8, this embodiment is identical with the embodiment shown in Fig.

7 in that the horizontal section Ml is formed on the inner side of the upper surface of the frame and a curved section (M3 and M3') extending downward and outward from the end of the horizontal section Ml is formed. However, the curved section comprises two curved sections M3 and M3' having different radii of curvature. In this embodiment, in particular, the radius of curvature of the curved section M3 adjacent to the horizontal section Ml is smaller than that of the curved section M3' formed on an outer side of the upper surface of the frame (rl<r2). However, the radius of curvature of the curved section M3 may be larger than that of the curved section M3' (rl>r2).

[55] Referring to Fig. 9, it can be seen that the frame 14 comprises a horizontal section

Ml formed on an inner side of an upper surface thereof, a curved section M3 extending downward and outward from an end of the horizontal section Ml, and a taper section M2 inclined downward and outward from an end of the curved section M3.

[56] The mask 10 is fixed through welding to several points on the taper section M2 of the frame in a state where a tensile force is applied to the mask 10 such that the edge 13 of the mask comes into close contact with the horizontal section Ml and the curved section M3 of the frame.

[57] The mask apparatus of the present invention may have any configuration so far as the welding points for fixing the mask to the frame are formed below the patterned surface of the mask. Accordingly, the present invention is not limited to the embodiments described above. For example, the welding points may be formed on an outer wall of the frame. Contrary to Fig. 9 showing that the upper surface of the frame has the horizontal section, the curved section and the taper section formed in this order from the inner side of the upper surface, the upper surface of the frame may have a horizontal section, a taper section and a curved section in this order. Other modifications can also be made. Industrial Applicability

[58] According to the present invention, a substrate is imaginarily divided into two or more regions and the regions are sequentially patterned. Thus, there is an advantage in that technical and economical problems in manufacturing a large- sized mask can be avoided.

[59] In particular, if a predetermined pattern is intended to be repeatedly formed on a substrate, a mask having a patterned surface corresponding to the predetermined pattern is manufactured and the mask is horizontally transferred or rotated or the substrate is transferred or rotated, thereby forming the pattern on the entire region of the substrate.

[60] In addition, since welding burrs do not come into contact with the substrate when the substrate is in close contact with the mask, the present invention has advantages in that it is possible to prevent damage to the substrate and to allow the substrate to be in closer contact with the mask.

Claims

[I] A mask apparatus for divided deposition of a substrate to form a pattern on the substrate, the mask apparatus comprising: at least one mask having a patterned surface for use in forming a pattern in any one of imaginarily divided, two or more regions of the substrate. [2] The mask apparatus as claimed in claim 1, wherein the mask comprises: a first mask having a patterned surface for use in forming a pattern in any one of the imaginarily divided, two or more regions of the substrate; and a second mask having a patterned surface for use in forming a pattern on the other region of the substrate. [3] The mask apparatus as claimed in claim 2, wherein the patterned surface of the first mask is identical with that of the second mask in area. [4] The mask apparatus as claimed in claim 2, wherein the patterned surface of the first mask is different from that of the second mask in area. [5] The mask apparatus as claimed in claim 2, wherein the first and second masks are mounted in an identical chamber, and the mask apparatus has a transfer means capable of horizontally transferring the first and second masks. [6] The mask apparatus as claimed in claim 2, wherein the first and second masks are mounted respectively in separate chambers. [7] The mask apparatus as claimed in claim 2, wherein the patterned surfaces of the first and second masks have patterns identical with patterns to be formed on an upper region and a lower region of the substrate, respectively. [8] The mask apparatus as claimed in claim 2, wherein the patterned surfaces of the first and second masks have patterns identical with patterns to be formed on a left region and a right region of the substrate, respectively. [9] The mask apparatus as claimed in claim 2, wherein the first and second masks are provided with alignment marks for allowing the masks to be aligned with the substrate. [10] The mask apparatus as claimed in claim 1, wherein the mask is welded to a frame, and welding points at which the mask is welded to the frame are formed below the patterned surface.

[I I] The mask apparatus as claimed in claim 10, wherein the frame is formed such that an outer side of an upper surface of the frame is lower than an inner side thereof.

[12] The mask apparatus as claimed in claim 11, wherein the upper surface of the frame has a taper section inclined downward and outward. [13] The mask apparatus as claimed in claim 11, wherein the upper surface of the frame has a curved section extending downward and outward. [14] The mask apparatus as claimed in claim 10, wherein the welding points are formed on an outer wall of the frame. [15] A method of divisionally forming patterns on a substrate, comprising the steps of:

1) preparing first and second masks each of which has a patterned surface for use in forming a pattern in one of imaginarily divided, two regions of the substrate;

2) bringing the first mask into close contact with the substrate to form a pattern on one of the regions of the substrate; and

3) bringing the second mask into close contact with the substrate to form a pattern on the other region of the substrate.

[16] The method as claimed in claim 15, wherein steps 2) and 3) are performed in an identical chamber.

[17] The method as claimed in claim 15, wherein steps 2) and 3) are performed respectively in separate chambers.

[18] A method of divisionally forming a predetermined pattern on a substrate to repeatedly form the pattern on the substrate, comprising the steps of:

1) preparing a mask having a patterned surface corresponding to the predetermined pattern;

2) brining the mask into contact with one of regions of the substrate to form the predetermined pattern on the region; and

3) transferring the mask and brining the mask into contact with another region of the substrate to form the predetermined pattern on the other region.

[19] The method as claimed in claim 18, wherein step 3) is carried out after the mask is transferred horizontally. [20] The method as claimed in claim 18, wherein step 3) is carried out after the mask is rotated.