U.S. patent application number 10/939381 was filed with the patent office on 2005-03-10 for mask and method of manufacturing the same, electro-luminescence device and method of manufacturing the same, and electronic instrument.
This patent application is currently assigned to Seiko Epson Corporation. Invention is credited to Yotsuya, Shinichi.
Application Number | 20050051516 10/939381 |
Document ID | / |
Family ID | 19109897 |
Filed Date | 2005-03-10 |
United States Patent
Application |
20050051516 |
Kind Code |
A1 |
Yotsuya, Shinichi |
March 10, 2005 |
Mask and method of manufacturing the same, electro-luminescence
device and method of manufacturing the same, and electronic
instrument
Abstract
A mask has a monocrystal substrate having opposite surfaces
which are planes having Miller indices {110}. A plurality of
penetrating holes are formed in the monocrystal substrate. An
opening shape of each of the penetrating holes is a polygon and
each side of the polygon is parallel with a plane in a group of the
{111} planes. The wall surfaces of the penetrating holes are the
{111} planes. In the method of manufacturing a mask, openings are
formed in the etching resistant film corresponding to the shape of
the penetrating holes and the monocrystal substrate is etched.
Inventors: |
Yotsuya, Shinichi;
(Suwa-city, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
Seiko Epson Corporation
Tokyo
JP
|
Family ID: |
19109897 |
Appl. No.: |
10/939381 |
Filed: |
September 14, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10939381 |
Sep 14, 2004 |
|
|
|
10246731 |
Sep 19, 2002 |
|
|
|
Current U.S.
Class: |
216/51 |
Current CPC
Class: |
G03F 1/20 20130101; H01L
51/56 20130101; C30B 33/00 20130101; G03F 7/12 20130101 |
Class at
Publication: |
216/051 |
International
Class: |
C23F 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 20, 2001 |
JP |
2001-287019 |
Claims
What is claimed is:
1. A mask comprising: a monocrystal substrate having opposite
surfaces having Miller indices {110}; and a plurality of
penetrating holes formed in the monocrystal substrate, wherein the
openings have a polygonal shape, each side of the openings being
parallel to a plane in a group of the {111} planes; and wherein
inside walls of the penetrating holes are the {111} planes.
2. The mask as defined in claim 1, wherein the shape of each of the
openings is a parallelogram.
3. The mask as defined in claim 2, wherein the thickness W of the
monocrystal substrate and the length L of a long side of the
parallelogram have the relationship: {square
root}3.times.W<L.
4. The mask as defined in claim 1, wherein the monocrystal
substrate is a monocrystal silicon substrate.
5. The mask as defined in claim 1, further comprising a magnetic
film formed on the monocrystal substrate.
6. The mask as defined in claim 1, wherein a thin portion is formed
in a region in which the penetrating holes are formed, within the
monocrystal substrate.
7. The mask as defined in claim 6, wherein the thin portion is
formed avoiding an edge portion of the monocrystal substrate.
8. The mask as defined in claim 6, wherein: a plurality of the thin
portions are formed in the monocrystal substrate; and each of the
thin portions is formed in a region including a group of the
penetrating holes.
9. A method of manufacturing an electro-luminescence device
comprising: forming a film of a light emitting material using the
mask as defined in claim 1.
10. An electro-luminescence device manufactured by the method as
defined in claim 9.
11. An electro-luminescence device comprising: a plurality of light
emitting layers each having an upper surface formed in a polygonal
shape except a rectangle, wherein the angle of each corner of the
polygonal shape is substantially equal to the intersection angle
between two planes among the planes having Miller indices
{111}.
12. The electro-luminescence device as defined in claim 11, wherein
the polygonal shape is a parallelogram.
13. An electronic instrument having the electro-luminescence device
as defined in claim 10.
14. An electronic instrument having the electro-luminescence device
as defined in claim 11.
Description
[0001] Japanese Patent Application No. 2001-287019, filed on Sep.
20, 2001, is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a mask and its
manufacturing method, an electro-luminescence device and its
manufacturing method, and an electronic instrument.
[0003] A mask with high precision is required. For example, a
method of manufacturing a color organic electro-luminescence
(hereinafter called EL) device that is known uses a mask to deposit
an organic material of each color. Though a method in which a base
is etched is known as one of the methods of manufacturing a mask,
it was difficult to manufacture a mask with high precision in the
conventional method.
BRIEF SUMMARY OF THE INVENTION
[0004] According to a first aspect of the present invention, there
is provided a method of manufacturing a mask comprising:
[0005] forming an etching resistant film having a plurality of
openings having a polygonal shape on surfaces of a monocrystal
substrate having Miller indices {110}, each side of the openings
being parallel to one of the {111} planes; and
[0006] forming a plurality of penetrating holes in the monocrystal
substrate within the openings by etching;
[0007] wherein the etching has a crystal orientation dependence
that the etching speed with respect to the {111} planes is slower
than the etching speed with respect to the {100} and {110}
planes.
[0008] According to a second aspect of the present invention, there
is provided a mask comprising:
[0009] a monocrystal substrate having opposite surfaces having
Miller indices {110}; and
[0010] a plurality of penetrating holes formed in the monocrystal
substrate,
[0011] wherein the openings have a polygonal shape, each side of
the openings being parallel to a plane in a group of the {111}
planes; and
[0012] wherein inside walls of the penetrating holes are the {111}
planes.
[0013] According to a third aspect of the present invention, there
is provided a method of manufacturing an electro-luminescence
device comprising forming a film of a light emitting material using
the above-described mask.
[0014] An electro-luminescence device according to a fourth aspect
of the present invention is manufactured by the above method.
[0015] An electro-luminescence device according to a fifth aspect
of the present invention comprises a plurality of light emitting
layers each having an upper surface formed in a polygonal shape
except a rectangle, and the angle of each corner of the polygonal
shape is substantially equal to the intersection angle between two
planes among the planes having Miller indices {111}.
[0016] An electronic instrument according to a sixth aspect of the
present invention has the electro-luminescence device.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0017] FIGS. 1A to 1C are diagrams illustrating a mask in
accordance with one embodiment of the present invention.
[0018] FIG. 2A is a plan view of a penetrating hole; FIG. 2B is a
perspective view of the penetrating hole; and FIG. 2C is a diagram
illustrating a crystal plane by using Miller indices.
[0019] FIGS. 3A to 3F are diagrams illustrating a method of
manufacturing a mask in accordance with one embodiment of the
present invention.
[0020] FIGS. 4A to 4C are diagrams illustrating a method of
manufacturing a mask in accordance with a second embodiment of the
present invention.
[0021] FIG. 5 is a diagram illustrating a method of manufacturing a
mask in accordance with a third embodiment of the present
invention.
[0022] FIG. 6 is a diagram illustrating a method of manufacturing a
mask and an EL device in accordance with a fourth embodiment of the
present invention.
[0023] FIGS. 7A to 7C are diagrams illustrating a method of forming
a film of a light emitting material.
[0024] FIGS. 8A and 8B are diagrams illustrating an EL device
manufactured by utilizing the method of forming a film of a light
emitting material according to the present invention.
[0025] FIG. 9 shows an electronic instrument in accordance with one
embodiment of the present invention.
[0026] FIG. 10 shows an electronic instrument in accordance with
one embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0027] Embodiments of the present invention may provide a mask with
high precision and its manufacturing method, an EL device and its
manufacturing method, and an electronic instrument.
[0028] (1) A method of manufacturing a mask according to one
embodiment of the present invention comprises:
[0029] forming an etching resistant film having a plurality of
openings having a polygonal shape on surfaces of a monocrystal
substrate having Miller indices {110}, each side of the openings
being parallel to one of the {111} planes; and
[0030] forming a plurality of penetrating holes in the monocrystal
substrate within the openings by etching;
[0031] wherein the etching has a crystal orientation dependence
that the etching speed with respect to the {111} planes is slower
than the etching speed with respect to the {100} and {110}
planes.
[0032] In accordance with this embodiment, each side of the
openings formed in the etching resistant film is parallel to one of
the {111} planes. Then, the etching having a crystal orientation
dependence is performed inside the openings, in a direction
perpendicular to the {110} planes of the monocrystal substrate.
Thus, since the penetrating holes perpendicular to the top surface
of the monocrystal substrate can be formed, the mask with high
precision can be manufactured.
[0033] (2) In this method of manufacturing a mask,
[0034] opposite surfaces of the monocrystal substrate may be the
{110} planes;
[0035] the etching resistant film having the openings may be formed
on the opposite surfaces; and
[0036] the etching may be advanced in the opposite surfaces of the
monocrystal substrate, depressed portions formed by the etching
being made into penetrating holes.
[0037] (3) In this method of manufacturing a mask,
[0038] the openings may include first openings formed on one
surface of the monocrystal substrate and second openings formed on
the other surface of the monocrystal substrate, the first and
second openings being correspondingly disposed to each other.
[0039] (4) In this method of manufacturing a mask,
[0040] the second openings may be smaller than the first openings,
and formed inside a projecting area of the first openings.
[0041] Thus, the positioning of the first and second openings can
be done more easily.
[0042] (5) In this method of manufacturing a mask,
[0043] the shape of each of the openings may be a
parallelogram.
[0044] (6) In this method of manufacturing a mask,
[0045] the thickness W of the monocrystal substrate and the length
L of a long side of the parallelogram may have the relationship:
{square root}3.times.W<L.
[0046] (7) In this method of manufacturing a mask,
[0047] the penetrating holes may be formed by forming small
penetrating holes in the monocrystal substrate by an energy beam,
and then enlarging the small penetrating holes by the etching.
[0048] Thus, the penetrating hole can be formed even in a thick
monocrystal substrate.
[0049] (8) In this method of manufacturing a mask,
[0050] mirror polishing may be carried out for the {110} plane of
the monocrystal substrate.
[0051] (9) In this method of manufacturing a mask,
[0052] the monocrystal substrate may be a monocrystal silicon
substrate.
[0053] (10) In this method of manufacturing a mask,
[0054] the etching resistant film may be formed of silicon oxide or
silicon nitride.
[0055] (11) In this method of manufacturing a mask,
[0056] an organic amine-based alkali aqueous solution and an
inorganic alkali aqueous solution may be used as an etchant.
[0057] (12) This method of manufacturing a mask may further
comprise forming a magnetic film on the monocrystal substrate after
the penetrating holes are formed.
[0058] Thus, the mask able to be adsorbed by magnetic force can be
manufactured.
[0059] (13) This method of manufacturing a mask may further
comprise forming a thin portion in a region in which the
penetrating holes are formed, within the monocrystal substrate.
[0060] Thus, the length of the penetrating hole in its axial
direction can be shorter than the size of opening (e.g. width) of
the penetrating hole. Further, strength can be held if the portion
except the region in which the penetrating hole is formed is the
thick wall in the monocrystal substrate.
[0061] (14) In this method of manufacturing a mask,
[0062] the thin portion may be formed avoiding an edge portion of
the monocrystal substrate.
[0063] Thus, the edge portion of the monocrystal substrate is part
of the thick wall so that strength can be held.
[0064] (15) In this method of manufacturing a mask,
[0065] the etching resistant film may be formed to have a first
portion which is in a region except a region in which the thin
portion is formed, and a second portion which is thinner than the
first portion and is disposed in a region in which the thin portion
is formed, the openings being formed in the second portion; and
[0066] the etching may be carried out to remove the second portion
first, an exposed portion in the first portion being then etched to
form the thin portion.
[0067] Thus, the thin portion and the penetrating hole can be
formed by forming the etching resistant film only once.
[0068] (16) In this method of manufacturing a mask,
[0069] the thin portion may be formed after the penetrating holes
are formed.
[0070] (17) In this method of manufacturing a mask,
[0071] the thin portion may be formed by etching with no crystal
orientation dependence.
[0072] This configuration makes it possible to form the thin
portion into a desired shape irrespective of the crystal
orientation.
[0073] (18) In this method of manufacturing a mask,
[0074] a plurality of the thin portions may be formed in the
monocrystal substrate, and each of the thin portions may be formed
in a region including a group of the penetrating holes.
[0075] (19) A mask according to one embodiment of the present
invention comprises:
[0076] a monocrystal substrate having opposite surfaces having
Miller indices {110}; and
[0077] a plurality of penetrating holes formed in the monocrystal
substrate,
[0078] wherein the openings have a polygonal shape, each side of
the openings being parallel to a plane in a group of the {111}
planes; and
[0079] wherein inside walls of the penetrating holes are the {111}
planes.
[0080] In accordance with this embodiment of the present invention,
a mask pattern can be formed with high precision since the
penetrating holes are formed perpendicularly to the opposite
surfaces of the monocrystal substrate.
[0081] (20) In this mask,
[0082] the shape of each of the openings may be a
parallelogram.
[0083] (21) In this mask,
[0084] the thickness W of the monocrystal substrate and the length
L of a long side of the parallelogram may have the relationship:
{square root}3.times.W<L.
[0085] (22) In this mask,
[0086] the monocrystal substrate may be a monocrystal silicon
substrate.
[0087] (23) This mask may further comprise a magnetic film formed
on the monocrystal substrate.
[0088] Thus, the mask can be adsorbed by magnetic force.
[0089] (24) In this mask,
[0090] a thin portion may be formed in a region in which the
penetrating holes are formed, within the monocrystal substrate.
[0091] In accordance with this configuration, the length of the
penetrating hole in its axial direction can be shorter than the
size of opening (e.g. width) of the penetrating hole. Further,
strength can be held if the portion except the region in which the
penetrating holes are formed is the thick wall in the monocrystal
substrate.
[0092] (25) In this mask,
[0093] the thin portion may be formed avoiding an edge portion of
the monocrystal substrate.
[0094] Thus, the edge portion of the monocrystal substrate is part
of the thick wall so that strength can be held.
[0095] (26) In this mask,
[0096] a plurality of the thin portions may be formed in the
monocrystal substrate; and
[0097] each of the thin portions may be formed in a region
including a group of the penetrating holes.
[0098] (27) A method of manufacturing an electro-luminescence
device according to one embodiment of the present invention
comprises forming a film of a light emitting material using the
above-described mask.
[0099] (28) An electro-luminescence device according to one
embodiment of the present invention is manufactured by the
above-described method.
[0100] (29) An electro-luminescence device according to one
embodiment of the present invention comprises a plurality of light
emitting layers each having an upper surface formed in a polygonal
shape except a rectangle,
[0101] wherein the angle of each corner of the polygonal shape is
substantially equal to the intersection angle between two planes
among the planes having Miller indices {111}.
[0102] (30) In this EL device,
[0103] the polygonal shape may be a parallelogram.
[0104] (31) An electronic instrument according to one embodiment of
the present invention has the EL device.
[0105] The preferred embodiments of the present invention will next
be explained with reference to the drawings.
[0106] First Embodiment
[0107] FIGS. 1A to 1C are diagrams illustrating a mask in
accordance with one embodiment of the present invention. FIG. 1B is
a sectional view taken along an IB-IB line of FIG. 1A. FIG. 1C is a
partially enlarged view of FIG. 1B. The mask has a monocrystal
substrate 10 (or is formed by only the monocrystal substrate 10).
For example, the monocrystal substrate 10 is a monocrystal silicon
substrate, or may be a silicon wafer. The monocrystal substrate 10
has surfaces having Miller indices {110}. For example, the top and
bottom surfaces of the monocrystal substrate 10 are {110} planes.
The {110} planes includes a plurality of planes equivalent to a
(110) plane. In a cubic lattice, directions perpendicular to the
{110} planes are <110> directions.
[0108] The monocrystal substrate 10 includes at least one (e.g.,
plural) thin portion 12. A plurality of the thin portions 12 may be
provided in a matrix. The monocrystal substrate 10 except the thin
portion 12 is a thick portion 16. Strength of the monocrystal
substrate 10 is held by the thick portion 16. The thin portion 12
is formed avoiding an edge portion of the monocrystal substrate 10.
Namely, the edge portion of the monocrystal substrate 10 is part of
the thick portion 16. Since the thin portion 12 is surrounded by
the thick portion 16, no thin portion 12 is easily deformed.
[0109] The thin portion 12 is located in a position biased on one
surface in the thickness direction of the monocrystal substrate 10.
Namely, the thin portion 12 is the bottom portion of a depressed
portion 14 formed on one surface (one of the opposite surfaces) of
the monocrystal substrate 10. In this case, the thin portion 12 and
the other portion (or thick portion 16) in the monocrystal
substrate 10 are located in the same level on a surface opposite to
the surface on which the depressed portion 14 is formed. As a
modified example, the depressed portion may be also formed in
corresponding positions on opposite surfaces (top and bottom
surfaces) of the monocrystal substrate 10. In this case, the thin
portion is located in the center in the thickness direction of the
monocrystal substrate 10.
[0110] As shown in FIG. 1C, plural penetrating holes 18 are formed
in the monocrystal substrate 10. A region in which the penetrating
holes 18 are formed is made into the thin portion 12. A group of
the penetrating holes 18 is formed in one thin portion 12.
[0111] FIG. 2A is a plan view of a penetrating hole, and FIG. 2B is
a perspective view of the penetrating hole. As mentioned above, the
surfaces of the monocrystal substrate 10 are the {110} planes. A
shape of the penetrating hole 18 is a polygon except a rectangle. A
shape of the penetrating hole 18 shown in FIG. 2A is a
parallelogram, and the length L of its long side and the thickness
W.sub.1. (see FIG. 1C) of the monocrystal substrate 10 (or the
thick portion 16 specifically) have the relationship: {square
root}3.times.W.sub.1<L. As a modified example, the length L of
the long side of the parallelogram and the thickness W.sub.2 (see
FIG. 1C) of the thin portion 12 of the monocrystal substrate 10 may
have the relationship: {square root}3.times.W.sub.2<L.
[0112] Each side of the opening of the penetrating hole 18 is
parallel to one of the {111} planes (specifically shown in FIGS. 2A
and 2B). In a cubic lattice, directions perpendicular to the {111}
planes are <111> directions.
[0113] FIG. 2C is a diagram illustrating a crystal plane by using
Miller indices. As can be seen from FIG. 2C, the {110} planes
perpendicularly intersect the {111} planes. The wall surface of the
penetrating hole 18 is one of the {111} planes (an example is shown
in FIGS. 2A and 2B). Accordingly, the penetrating hole 18 is
disposed perpendicularly to the top and bottom surfaces of the
monocrystal substrate 10 (the {110} planes). Since the penetrating
hole 18 is formed perpendicularly to the top and bottom surfaces of
the monocrystal substrate 10, a mask pattern is formed with high
precision.
[0114] FIGS. 3A to 3F are diagrams illustrating a method of
manufacturing a mask in accordance with one embodiment of the
present invention. In this embodiment, the monocrystal substrate 10
is prepared in a state prior to the formation of the penetrating
hole 18, etc. For example, the monocrystal substrate 10 is a
monocrystal silicon substrate, and may be also a silicon wafer. The
monocrystal substrate 10 has surfaces having Miller indices {110}.
For example, the top and bottom surfaces (opposite surfaces) of the
monocrystal substrate 10 are the {110} planes. Mirror polishing may
be carried out for at least the top surface (or opposite surfaces)
of the monocrystal substrate 10.
[0115] As shown in FIG. 3A, an etching resistant film 20 (e.g., a
thickness of about 1 .mu.m) is formed in the monocrystal substrate
10. The etching resistant film 20 is formed on each of the top and
bottom surfaces (opposite surfaces) of the monocrystal substrate
10. The etching resistant film 20 may be arranged so as to
continuously cover the entire surface of the monocrystal substrate
10. The etching resistant film 20 may be formed by silicon oxide
and silicon nitride using thermal oxidation processing.
[0116] As shown in FIG. 3B, a plurality of openings 22 are formed
in the etching resistant film 20. A pair of openings 22 is
oppositely provided on the top and bottom surfaces (opposite
surfaces) of the monocrystal substrate 10. Each of the openings 22
is formed so as to have the same shape as the penetrating hole 18
in a position in which the penetrating hole 18 is formed. The
opening 22 is formed in a polygonal shape (e.g., a parallelogram).
Each side of the opening 22 is located in parallel with one of the
{111} planes. The other details about the shape of the opening 22
are the same as the penetrating hole 18. Photolithography can be
applied to the formation of the opening 22.
[0117] As shown in FIG. 3C, the etching resistant film 20 is
patterned so as to have a first portion 24 avoiding an area for
forming the thin portion 12, and a second portion 26 arranged in
the area for forming the thin portion 12 and thinner than the first
area 24. The photolithography may be also applied to this
patterning. When the patterning is terminated, the opening 22 is
located in the second portion 26. The outer shapes (planar shapes)
of the first and second portions 24, 26 are respectively the same
as the outer shapes (planar shapes) of the thick portion 16 and the
thin portion 12.
[0118] The monocrystal substrate 10 is then etched with the etching
resistant film 20 having the first and second portions 24, 26 as a
mask. The etching applied here is anisotropic etching, and has a
crystal orientation dependence that the etching speed with respect
to the {111} planes is slower than the etching speed with respect
to the {100} and {110} planes (e.g., slower by 10 times or more,
preferably 100 times or more). Note that a 15 percent potassium
hydroxide solution heated to about 80.degree. C. may be used as an
etchant. When it is desirable to avoid potassium, an organic
amine-based alkali aqueous solution, e.g., 10 to 20 percent by
weight aqueous solution of tetramethyl ammonium hydroxide may be
used as an etchant. Otherwise, an inorganic alkali aqueous solution
except the potassium hydroxide aqueous solution, e.g., ammonia
water may be also used. In this embodiment, since there are exposed
portions by the openings 22 on the opposite surfaces of the
monocrystal substrate 10, the etching is advanced on the opposite
sides.
[0119] As shown in FIG. 3D, the penetrating hole 18 is formed
within the opening 22 of the etching resistant film 20. The
thickness W.sub.1 (see FIG. 1C) of the monocrystal substrate 10 and
the length L of a long side of the parallelogram of the opening 22
(the same as the length L of a long side of the parallelogram of
the penetrating hole 18 shown in FIG. 2A) have the relationship:
{square root}3.times.W.sub.1<L. Accordingly, the depressed
portion formed by the etching can be penetrated without
intermediately stopping the etching from the opposite sides.
[0120] As shown in FIG. 3E, the second portion 26 is early removed
in comparison with the first portion 24 by reducing the thickness
of the etching resistant film 20. This process may be also
performed by the etching. Thus, the monocrystal substrate 10
forming the penetrating hole 18 therein is covered with the first
portion 24 among the etching resistant film 20. The surface of the
monocrystal substrate 10 exposed by removing the second portion 26
is a forming area of the thin portion 12.
[0121] As shown in FIG. 3F, the thin portion 12 can be formed by
etching the exposed surface from the first portion 24 in the
monocrystal substrate 10. If etching having no crystal orientation
dependence is applied as this etching, the thin portion 12 having a
desired shape can be formed. In this embodiment, after the
penetrating hole 18 is formed, the thin portion 12 is formed. Since
the details of the thin portion 12 have been described above, its
explanation is omitted here. The mask shown in FIGS. 1A to 1C can
be manufactured by removing the etching resistant film 20 (first
portion 24 in detail).
[0122] In accordance with this embodiment, each side of the opening
22 formed in the etching resistant film 20 is parallel to one of
the {111} planes. Then, the etching having a crystal orientation
dependence is performed inside the opening 22, in a direction
perpendicular to the {110} planes of the monocrystal substrate 10.
Thus, since the penetrating hole 18 perpendicular to the top
surface of the monocrystal substrate 10 can be formed, the mask
with high precision can be manufactured.
[0123] In this embodiment, the thin portion 12 is formed, but the
present invention includes an example in which no thin portion 12
is formed. When no thin portion 12 is formed, the forming process
of the second portion 26 shown in FIG. 3C and the processes after
FIG. 3E are not required.
[0124] Second Embodiment
[0125] FIGS. 4A to 4C are diagrams illustrating a method of
manufacturing a mask in accordance with a second embodiment of the
present invention. In the first embodiment, the openings 22 are
formed in the etching resistant film 20 on opposite surfaces of the
monocrystal substrate 10. In this case, since it is difficult to
align the positions of the openings 22 on opposite sides, a method
for simply aligning these positions will next be mainly
explained.
[0126] As shown in FIG. 4A, a first opening 34 is formed in an
etching resistant film 30 formed on one surface of the monocrystal
substrate 10, and a second opening 36 is formed in an etching
resistant film 32 formed on the other surface. Here, the widths A,
B of the first and second openings 34, 36 have the relationship:
B<A. Accordingly, it is sufficient to form the second opening 36
inside a projecting area of the first opening 34. Its positioning
is simpler than the alignment of the openings of the same size.
Thus, the first opening 34 on one side and the second opening 36 on
the other side are correspondingly formed in the above etching
resistant films 30, 32 respectively formed on opposite surfaces of
the monocrystal substrate 10. The etching is advanced as shown in
FIG. 4B, and a penetrating hole 38 is formed as shown in FIG. 4C.
As shown in FIG. 4C, part of the etching resistant film 32 defining
the second opening 36 of a smaller size is projected inside the
penetrating hole 38, but the etching resistant film 32 may be
removed. The contents explained in this embodiment can be applied
to the first embodiment.
[0127] Third Embodiment
[0128] FIG. 5 is a diagram illustrating a method of manufacturing a
mask in accordance with a third embodiment of the present
invention. In the first embodiment, the thickness W.sub.1 (see FIG.
1C) of the monocrystal substrate and the length L of a long side of
the parallelogram of the opening 22 of the etching resistant film
20 (the same as the length L of a long side of the parallelogram of
the penetrating hole 18 shown in FIG. 2A) have the relationship:
{square root}3.times.W.sub.1<L. The penetrating hole can be
formed in such a comparatively thin monocrystal substrate. However,
in a monocrystal substrate thicker than this comparatively thin
monocrystal substrate, the etching is intermediately stopped so
that no penetrating hole can be formed.
[0129] In this embodiment, the forming method of the penetrating
hole will be explained when the relationship: {square
root}3.times.W.sub.1.gtoreq.L is formed (when the monocrystal
substrate is thick).
[0130] As shown in FIG. 5, a small penetrating hole (a hole smaller
than the penetrating hole) 42 is formed in advance before the
etching in a forming area of the penetrating hole in the
monocrystal substrate 10 (an exposed surface from a patterned
etching resistant film 40). The small penetrating hole 42 is formed
by an energy beam (e.g., YAG laser). Thus, since a corner portion
is formed in an opening portion of the small penetrating hole 42,
the penetrating hole can be formed without stopping the advancement
of the etching. The contents explained in this embodiment can be
applied to the first embodiment.
[0131] Fourth Embodiment
[0132] FIG. 6 is a diagram illustrating a method of manufacturing a
mask and an EL device in accordance with a fourth embodiment of the
present invention. A magnetic film 52 is formed in the mask 10
shown in FIG. 6. The magnetic film 52 can be formed by a
ferromagnetic material such as iron, cobalt, and nickel. Otherwise,
the magnetic film 52 may be also formed by a magnetic metal
material such as Ni, Co, Fe, and a stainless steel alloy including
an Fe component, and bonding of the magnetic metal material and a
nonmagnetic metal material. The other details of the mask 10 have
been explained in the first embodiment.
[0133] In this embodiment, the film of a light emitting material is
formed in a substrate 54 by using the mask 10. The substrate 54 is
arranged for an EL device (e.g., organic EL device) and is a
transparent substrate such as a glass substrate. As shown in FIG.
7A, an electrode (e.g., a transparent electrode constructed by ITO,
etc.) 56 and a positive hole transport layer 58 are formed in the
substrate 54. An electronic transport layer may be also formed. The
mask 10 is arranged such that the depressed portion 14 is directed
on the side opposed to the substrate 54. Namely, a flat surface of
the mask 10 is directed to the substrate 54 side. A magnet 50 is
arranged behind the substrate 54 so as to attract the magnetic film
52 formed in the mask 10. Thus, even when a warp is caused in the
mask 10, this warp can be corrected.
[0134] FIGS. 7A to 7C are diagrams illustrating a method of forming
a film of a light emitting material. For example, the light
emitting material is an organic material, and there is
alumiquinolinol complex (Alq.sub.3) as the organic material of low
molecule, and there is polyparaphenylene vinylene (PPV) as the
organic material of high molecule. The film of the light emitting
material can be formed by evaporation. For example, as shown in
FIG. 7A, while a red light emitting material is patterned through
the mask 10, the film is formed and a red light emitting layer 60
is formed. As shown in FIG. 7B, while the mask 10 is shifted and a
green light emitting material is patterned, the film is formed and
a green light emitting layer 62 is formed. As shown in FIG. 7C,
while the mask 10 is again shifted and a blue light emitting
material is patterned, the film is formed and a blue light emitting
layer 62 is formed.
[0135] FIGS. 8A and 8B are diagrams illustrating an EL device
manufactured by utilizing the above-described method of forming a
film of a light emitting material. The EL device (e.g., organic EL
device) has a substrate 54, an electrode 56, a positive hole
transport layer 58, light emitting layers 60, 62, 64, etc. As shown
in FIG. 8B, the shape of upper surface of each of the light
emitting layers 60, 62, 64 is a polygon (e.g., a parallelogram)
except a rectangle. This shape corresponds to the shape of the
penetrating hole 18 of the mask 10. The details have been described
in the first embodiment. Further, an electrode 66 is formed on the
light emitting layers 60, 62, 64. For example, the electrode 66 is
a cathode electrode. The EL device (EL panel) becomes a display
device (display).
[0136] A notebook personal computer 1000 is shown in FIG. 9 and a
portable telephone 2000 is shown in FIG. 10 as an electronic
instrument having an EL device in accordance with one embodiment of
the present invention.
[0137] Note that this invention is not limited to the embodiments
described above and thus it can be implemented in many various
ways. For example, the present invention includes various other
configurations substantially the same as the configurations
described in the embodiments (in function, method and result, or in
objective and result, for example). The present invention also
includes a configuration in which an unsubstantial portion in the
described embodiments is replaced. The present invention also
includes a configuration having the same effects as the
configurations described in the embodiments, or a configuration
able to achieve the same objective. Further, the present invention
includes a configuration in which a publicly known technique is
added to the configurations in the embodiments.
* * * * *