U.S. patent application number 11/010355 was filed with the patent office on 2005-05-12 for mask for vacuum deposition and organic el display panel manufactured by using the same.
This patent application is currently assigned to TOHOKU PIONEER CORPORATION. Invention is credited to Abiko, Hirosi.
Application Number | 20050098110 11/010355 |
Document ID | / |
Family ID | 29243767 |
Filed Date | 2005-05-12 |
United States Patent
Application |
20050098110 |
Kind Code |
A1 |
Abiko, Hirosi |
May 12, 2005 |
Mask for vacuum deposition and organic EL display panel
manufactured by using the same
Abstract
A mask for vacuum deposition that is held by a mask frame is
provided. The mask comprises a mask body for deposition; a guide
member fixed to at least one side of the mask body for deposition;
and tension applying means that, when the guide member is held by
the mask frame, applies a predetermined tension to the mask body
for deposition via the guide member.
Inventors: |
Abiko, Hirosi;
(Yonezawa-shi, JP) |
Correspondence
Address: |
WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP
1250 CONNECTICUT AVENUE, NW
SUITE 700
WASHINGTON
DC
20036
US
|
Assignee: |
TOHOKU PIONEER CORPORATION
|
Family ID: |
29243767 |
Appl. No.: |
11/010355 |
Filed: |
December 14, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11010355 |
Dec 14, 2004 |
|
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10259664 |
Sep 30, 2002 |
|
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Current U.S.
Class: |
118/715 |
Current CPC
Class: |
H01L 51/001 20130101;
H01L 51/0013 20130101; C23C 14/042 20130101; H01L 51/56
20130101 |
Class at
Publication: |
118/715 |
International
Class: |
C23C 016/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 26, 2002 |
JP |
2002-125276 |
Claims
1-11. (canceled)
12. An organic EL display panel manufactured by the use of a mask
for vacuum deposition that comprises: a mask body for deposition; a
guide member fixed to at least one side of the mask body for
deposition; and tension applying means that, when the guide member
is held by the mask frame, applies a predetermined tension to the
mask body for deposition via the guide member.
13. An organic EL display panel as claimed in claim 12, wherein the
mask body for deposition has a mask pattern in which apertures are
arranged in a predetermined pattern and has the guide member fixed
to at least one side in the direction perpendicular to the
direction of length of the aperture.
14. An organic EL display panel as claimed in claim 13, wherein the
guide members are fixed to the two sides of the mask body for
deposition that are opposed to each other.
15. An organic EL display panel as claimed in claim 12, wherein the
guide members are fixed to the four sides of the mask body for
deposition.
16. An organic EL display panel as claimed in claim 12, wherein the
tension applying means includes a screw hole formed in the side
wall of the guides member and a screw which is screwed into the
screw hole whose tip portion is made to abut against the side wall
of the mask frame.
17. An organic EL display panel as claimed in claim 16, wherein a
spring member is provided between the mask frame and the guide
member.
18. An organic EL display panel as claimed in claim 17, wherein the
spring member is a compression spring.
19. An organic EL display panel as claimed in claim 17, wherein the
spring member is a leaf spring.
20. An organic EL display panel as claimed in claim 12, wherein the
tension applying means includes a through hole formed in the side
wall of the guide member, a screw which is passed through the
through hole whose tip portion is screwed into a screw hole made in
the side wall of the mask frame, and a spring member provided
between the mask frame and the guide member.
21. An organic EL display panel as claimed in claim 20, wherein the
spring member is a compression spring.
22. An organic EL display panel as claimed in claim 20, wherein the
spring member is a leaf spring.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a mask for vacuum
deposition and an organic EL display panel manufactured by using
the same.
[0003] 2. Description of the Related Art
[0004] In recent years, in the pixels of a light emitting device
such as an organic EL, as colorization goes forward, a minimum
pitch between RGB has been made as fine as nearly 50 .mu.m and
additionally, a study of making the pitch finer has been also
conducted.
[0005] On the other hand, the size of a mask for vacuum deposition
used for manufacturing the organic EL is as large as about from 400
mm to 500 mm and there has been a tendency for the mask for vacuum
deposition to become larger with the increasing size of a display
panel using the organic EL. In this manner, there has been a
tendency that the mask for vacuum deposition used for manufacturing
the light emitting device such as organic EL is made larger in size
and that a mask pitch between its mask patterns is made
narrower.
[0006] If the mask pitch of the mask for vacuum deposition that is
made larger in size is made narrower, as described above, then the
rigidity of the mask for vacuum deposition itself is decreased and
thus when the mask for vacuum deposition is fixed to a mask frame
of its holding member, a deflection is produced.
[0007] In order to remove the deflection, it is necessary to apply
a tension to the mask for vacuum deposition. For this reason, in
the related art, in the state where a tension is applied to the
mask for vacuum deposition to remove the deflection, the end
portion of the mask for vacuum deposition is bonded to the mask
frame with an adhesive or is fixed welded thereto by welding, or is
clamped with screws.
[0008] However, the conventional method of fixing the mask for
vacuum deposition to the mask frame presents a problem that since
it is difficult to adjust the tension of the mask for vacuum
deposition after it is fixed, it is impossible to correct the mask
for vacuum deposition when it is deflected by some causes after it
is fixed.
[0009] Further, the above-described method in the related art
presents a problem that since it is difficult to dismount the mask
for vacuum deposition from the mask frame, it is difficult to clean
the mask for vacuum deposition and to change the mask for vacuum
deposition when the mask pattern of the mask for vacuum deposition
is changed. Still further, the method in the related art presents a
problem that since it is difficult to dismount the mask for vacuum
deposition, the mask frame can not be used again.
SUMMARY OF THE INVENTION
[0010] The present invention has been made to solve the
above-mentioned problems. It is the object of the present invention
to provide a mask for vacuum deposition that is not directly fixed
to a mask frame so that the tension of the mask for vacuum
deposition can be adjusted in a state where it is held by the mask
frame and that can be easily removed from the mask frame, and an
organic EL display panel manufactured by using the same.
[0011] A mask for vacuum deposition in accordance with the present
invention to achieve the above-mentioned object is a mask for
vacuum deposition that is held by a mask frame and is characterized
by a mask body for deposition, a guide member fixed to at least one
side of the mask body for deposition, and tension applying means
that, when the guide member is held by the mask frame, applies a
predetermined tension to the mask body for deposition via the
guided member.
[0012] As described above, since the mask for deposition is not
directly fixed to the mask frame, the mask for deposition can be
easily dismounted from the mask frame. Further, since a
predetermined tension is applied to at least one side of the mask
frame, when the mask for deposition is held by the mask frame, the
deflection of the mask body for deposition can be prevented.
[0013] Here, it is preferable that the above-mentioned mask body
for deposition has a mask pattern in which apertures are arranged
in a predetermined pattern and has the guide member fixed to at
least one side in the direction perpendicular to the direction of
length of the aperture.
[0014] This makes it possible to apply a tension in the direction
along the arrangement of the predetermined pattern and to stretch
the mask body for deposition so as to prevent the deflection of the
mask body for deposition. Therefore, deposited pixels can be formed
in more accurate shapes.
[0015] Further, it is preferable that the guide members are fixed
to the two sides of the mask body for deposition that are opposed
to each other.
[0016] This makes it possible to apply a tension in two directions
of front and back directions or right and left directions and thus
to prevent the deflection of the mask for deposition more
surely.
[0017] It is preferable that the guide members are fixed to the
four sides of the mask body for deposition.
[0018] This makes it possible to apply a tension in four
directions, that is, in all directions of front and back directions
and right and left directions and thus to more surely prevent the
deflection of the mask for deposition. Moreover, one of the
respective sides opposed to each other may be directly bonded to a
tray.
[0019] Further, it is preferable that the tension applying means
includes a through hole formed in the side wall of the guide member
and a screw which is passed through the through hole and whose tip
portion is screwed into a screw hole made in the side wall of the
mask frame.
[0020] Such tension applying means makes it possible to prevent the
deflection of the mask for deposition more surely and easily.
[0021] Here, it is preferable that a spring member is provided
between the mask frame and the guide member. Preferably, the spring
member is a compression spring. The spring member may be a leaf
spring.
[0022] Still further, it is preferable that the tension applying
means includes a through hole formed in the side wall of the guide
member, a screw which is inserted into the through hole and whose
tip portion is made to abut against the side wall of the mask
frame, and a spring member provided between the mask frame and the
guide member.
[0023] Such tension applying means also makes it possible to
prevent the deflection of the mask for deposition more surely and
easily.
[0024] Here, it is preferable that a spring member is provided
between the mask frame and the guide member. Preferably, the spring
member is a compression spring. The spring member may be a leaf
spring.
[0025] Moreover, an organic EL display panel in accordance with the
present invention is characterized in that it is manufactured by
the use of any one of the above-mentioned mask for vacuum
deposition.
[0026] The use of any one of the above-mentioned masks for vacuum
deposition makes it possible to form deposited pixels in more
accurate shapes in the organic EL display panel made of a light
emitting device having a finer pixel pitch and thus to produce an
organic EL display panel capable of displaying an image of high
quality.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1is a perspective view to show a mask for vacuum
deposition in an embodiment in accordance with the present
invention and is illustrative of a state where the mask for vacuum
deposition is dismounted from a mask frame;
[0028] FIG. 2 is a perspective view to show a mask for vacuum
deposition in an embodiment in accordance with the present
invention and is illustrative a state where the mask for vacuum
deposition is mounted on a mask frame;
[0029] FIG. 3 is a perspective view to show a main part of the
embodiment in accordance with the present invention;
[0030] FIG. 4 is a cross-sectional view taken on a line A-A in FIG.
3; and
[0031] FIG. 5 is a perspective view of a compression coil
spring.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] In the preferred embodiments, a case will be described in
detail where a mask for vacuum deposition in accordance with the
present invention is applied to the vacuum deposition of an organic
layer when an organic EL display panel is manufactured. FIG. 1 and
FIG. 2 illustrate a mask for vacuum deposition in an embodiment in
accordance with the present invention.
[0033] The mask 1 for vacuum deposition in an embodiment in
accordance with the present invention is used for forming an
organic EL device and is held by a mask frame 11 in a deposition
process (mainly in forming an organic layer) when the organic EL
device is manufactured.
[0034] As shown in FIG. 1, the mask 1 for vacuum deposition has a
mask body 10 for deposition, guide members 12, and tension applying
means 14.
[0035] The mask body 10 for deposition and the mask frame 11 is
formed of stainless steel such as SUS344, SUS303, SUS316, SUS430,
Ti (titanium), other metals, or ceramics. Further, the mask frame
11 is formed in a thickness of from 1 mm to 100 mm, preferably,
from 4 mm to 30 mm.
[0036] Further detailing the mask for vacuum deposition, as shown
in FIG. 1, two sides of the mask body 10 for vacuum deposition,
which are opposed to each other, are fixed to the guide members 12,
12 by spot welding and the like. In fixing the mask body 10 for
vacuum deposition to the guide members 12, 12, it is essential that
the mask body 10 for vacuum deposition be fixed to the guide
members 12, 12, so that means such as an adhesive or a clamp may be
used.
[0037] Then, these guide members 12, 12 is nearly as long as the
mask body 10 for vacuum deposition.
[0038] Moreover, these guide members 12, 12 are mounted with means
14 for applying a predetermined tension to the mask 10 for vacuum
deposition.
[0039] Then, on the mask body 10 for deposition are formed mask
patterns 10a. The mask patterns 10a are used for depositing pixels
for constituting the organic EL display and are formed on the mask
body 10 for deposition in the shape of a grid having a fine
pitch.
[0040] Each of the mask patterns 10a formed in the shape of a grid
has a plurality of apertures arranged in a predetermined pattern.
The apertures arranged in the mask pattern 10a are formed in the
shape of a slit, a slot, a circle and the like and are arranged in
a square, in a stagger and the like.
[0041] If a tension is applied to the mask body 10 for deposition
in the direction along the arrangement of the apertures of the mask
patterns 10a (which is shown as streaks in the mask pattern 10a in
FIG. 1, FIG. 2) to stretch the mask body 10 for deposition so as to
remove its deflection, it is possible to form the pixels to be
deposited in more accurate shapes.
[0042] For this reason, as shown in FIG. 1, FIG. 2, the guide
members 12, 12 are fixed to the two sides of the mask body 10 for
deposition which are arranged in the direction perpendicular to the
direction of length of the apertures (which is shown as streaks in
the mask pattern 10a in FIG. 1, FIG. 2) of the mask pattern 10a and
are opposed to each other.
[0043] Then, as shown in FIG. 2, by mounting the mask 1 for vacuum
deposition on the mask frame 11, a deposition operation can be
performed.
[0044] Further, a structure for applying a tension to the mask body
10 for deposition when the mask 1 for vacuum deposition is mounted
on the mask frame 11 will be described in detail.
[0045] FIG. 3 is a perspective view to show a main part of an
embodiment in accordance with the present invention in order to
describe a structure for applying a tension to the mask body 10 for
deposition. FIG. 4 is a cross-sectional view taken on a line A-A in
FIG. 3.
[0046] FIG. 3 is an illustration to show one side to which the
guide member 12 in FIG. 1 is fixed and in which screws 16, which
are the parts of the tension applying means 14, are fixed to the
side surface of the guide member 12.
[0047] Further, describing the tension applying means 14 in detail,
as shown in the cross-sectional view in FIG. 4, through holes are
made in the side wall of the guide member 12 and the tip of the
screw 16 passed through the through hole is screwed into a screw
hole (which is not shown) made in the side wall of the mask frame
11. That is, by turning the screw 16, the guide member 12 through
which the screw 16 is passed is moved to thereby adjust a tension
applied to the mask body 10.
[0048] Moreover, a compression coil spring 17 that is a spring
member shown in FIG. 5, for example, is put on the screw 16 between
the mask frame 11 and the guide member 12 and, the tension of the
compression coil spring 17 moves the guide member 12 and can add a
tension applied to the mask body 10. This produces an effect that
the screw 16 and the guide member 12 can be prevented from
rattling.
[0049] A method of adjusting the tension of the mask body 10
includes a method of bringing the mask body 10 into a state where
the mask body 10 is not wrinkled visually, a method of measuring
the torque of the respective screws and making the torque a fixed
value, and a method of adjusting the respective screws so that the
error between an alignment mark on the mask and an alignment mark
on a scale is smaller than a predetermined value.
[0050] In this respect, the above-mentioned spring member may be a
leaf spring in place of the compression coil spring 17. Moreover,
it is also recommended that a through hole through which the shaft
of the screw 16 is passed be made in the side wall of the guide
member 12 and that the tip of the screw 16 be screwed into a screw
hole (which is not shown) made in the side wall of the mask frame
11 and that the compression coil spring 17, which is a spring
member shown in FIG. 5, be provided between the mask frame 11 and
the guide member 12. The tensile force of this compression coil
spring 17 moves the guide member 12 to add a tension applied to the
mask body 10.
[0051] Here, by adjusting the length of protrusion of the screw 16
from the side wall of the mask frame 11, a tension applied to the
mask body 10 can be adjusted.
[0052] A standard screw such as M2 to M5 may be used as the screw
16 described above. Here, the pitch of M2 is 0.4 mm, the pitch of
M3 is 0.5 mm, the pitch of M4 is 0.7 mm, and the pitch of M5 is 0.8
mm.
[0053] As described above, in the mask 1 for vacuum deposition in
accordance with the present embodiment, the guide members 12, 12
can be removed from the mask frame 11 by turning the screws 16 and
thus the mask body 10 for deposition can be easily dismounted from
the mask frame 11.
[0054] Therefore, the mask body 10 for deposition and the mask
frame 11 can be easily cleaned, and when the mask pattern 10a is
changed, the mask body 10 for deposition can be easily changed by
reusing the mask frame 11.
[0055] Incidentally, in the above-mentioned embodiment, the guide
members 12, 12 are fixed to the two sides of the mask body 10 for
deposition which are opposed to each other to apply the tension to
the mask body 10 for deposition. By fixing the guide members 12 to
the respective four sides of the mask body 10 for deposition,
however, it is also possible to apply the tension to the four sides
of the mask body 10 for deposition and, in this case, it is
possible to more surely prevent the deflection of the mask body 10
for deposition.
[0056] As described above in detail, according to the mask for
vacuum deposition in accordance with the present invention, it is
possible to adjust the tension of the mask for deposition in a
state where it is held by the mask frame and to easily dismount the
mask for deposition from the mask frame.
[0057] Moreover, according to the organic EL display panel in
accordance with the present invention, deposited pixels can be
formed in more accurate shapes, which makes it possible to display
an image of high quality.
* * * * *