Electrical generator or motor structure – Dynamoelectric – Linear
Reexamination Certificate
2000-09-08
2002-12-17
Ramirez, Nestor (Department: 2834)
Electrical generator or motor structure
Dynamoelectric
Linear
C310S049540, C029S596000
Reexamination Certificate
active
06495934
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a method of manufacturing a linear motor suitably used for a driving power source for a stage holding a substrate in a projection exposure apparatus used in, for example, semiconductor manufacturing steps; a linear motor; a stage apparatus equipped with the linear motor; and an exposure apparatus.
BACKGROUND OF THE INVENTION
In a photolithography step which occupies an important place in manufacturing steps for manufacturing devices such as semiconductor devices and liquid crystal devices, a projection exposure apparatus has been heretofore employed, which projects and exposes via a projection optical system a circuit pattern of a photomask or a reticle (hereinafter simply referred to as a reticle) onto a substrate such as a wafer and a glass plate on which photosensitive agent is coated. Recently, as the integration density of the semiconductor integrated circuits continues to increase, a reduction projection type exposure apparatus, called a stepper, adopting a step and repeat system has been the primary projection exposure apparatus. The reduction projection type exposure apparatus sequentially projects and transfers a pattern onto a plurality of exposure areas on a substrate while sequentially moving the substrate.
In such a stepper, every time a projection and a transfer are performed while sequentially moving a substrate, the substrate needs to be positioned precisely. Accordingly, a stage for holding, moving, and positioning the substrate is provided. The stage, in which a movable stage making it possible to move the held substrate at least in two directions is provided, and a translatory driving mechanism is in heavy usage as a driving power source for the movable stage.
The translatory driving mechanism includes one which converts a rotary motion to a translatory motion by use of a rotary motor, and another using a translatory type linear motor. Particularly, because the linear motor has a simple structure, a small number of parts, and offers low frictional resistance, the linear motor has come to be a principle driving power source for a mechanism which must perform precise positioning.
The linear motor is composed of a permanent magnet unit and an armature coil unit, which allows the permanent magnet unit and the armature coil unit to move relative to each other, thus generating a propulsive force.
As shown in
FIG. 13
, there has been heretofore an armature coil unit
2
of a linear motor
1
, which has a structure in which a plurality of coil bodies
3
are arrayed.
Each of the coil bodies
3
is constructed by winding up a wire into an almost rectangular shape when viewed sideways, and has an opening portion
3
a
in its central portion. The plurality of coil bodies
3
are positioned relative to a fitting plate
4
by inserting each opening portion
3
a
into corresponding one of the protrusions
4
a
formed so as to correspond to each opening portion
3
a.
Also a technology to achieve high performance of the linear motor by increasing the occupation rate (density) of the armature coil unit for a magnetic gap of the permanent magnet unit has been recently proposed. For example, in the technology disclosed in Japanese Unexamined Patent Application, First Publication No. Hei 8-168229, a linear motor using a flat coil is proposed.
As shown in
FIG. 14A
, a linear motor
5
proposed in the above publication is schematically constituted by permanent magnets
7
and
7
held by a magnet frame
6
so as to face each other with a predetermined interval therebetween, and an armature coil unit
8
disposed between the permanent magnets
7
and
7
. The armature coil unit
8
has a constitution in which flat-shaped coils
9
adheres to both planes of a fitting plate
8
a
. As shown in
FIG. 14B
, each coil
9
is formed to be flat-shaped by bending spirally a band-shaped coil which is wound into a rectangle or a parallelogram having a long side. Each coil
9
is positioned by a pin
8
b
provided on a fitting plate
8
a.
However, in the foregoing conventional linear motor
1
shown in FIG.
13
, the following problems exist.
First, in the linear motor
1
shown in
FIG. 13
, the positioning precision of each coil body
3
in the array direction of the plurality of coil bodies
3
is important. Specifically, as shown in
FIG. 15
, when there are external shape dimension errors among the coil bodies
3
, an array interval of the plurality of coil bodies
3
arrayed deviates relatively from an array interval of the permanent magnets
7
with an accumulation of the errors. When there is an error between the array interval of the permanent magnets
7
and the array interval of the coil bodies
3
, unevenness occurs in a propulsive force generated in the linear motor
1
, thus influencing performance of the linear motor
1
. As a countermeasure for this, though the external dimension precision of each coil body
3
must be increased, the increase in the external dimension precision results in an increase in the coil manufacturing cost.
In addition, in the linear motor
1
shown in
FIG. 13
, since the opening portion
3
a
is formed in each coil body
3
, the occupation rate (density) of the coil body
3
for a magnetic gap of the permanent magnet unit is lowered in the opening portion
3
a
. As a result, there is the problem that an efficiency of the linear motor
1
is lowered.
On the other hand, in the linear motor
5
shown in
FIG. 14
, since the coil
9
equivalent to one phase is wound all in one, the problem owing to the deviation of the array interval created in the linear motor
1
shown in
FIG. 13
can be avoided. However, in the linear motor
5
shown in
FIG. 14
, the fitting plate
8
a
as well as the coil
9
are interposed between the permanent magnets
7
and
7
, and the occupation rate of the coil
9
for the magnetic gap of the permanent magnets
7
and
7
is lowered by the fitting plate
8
a
, so that efficiency of the linear motor
1
is still influenced. In addition, there is also the problem that such a coil
9
requires a large scale winding apparatus for manufacturing it.
The present invention was made considering the above described circumstances, and the subject of the present invention is to provide a method of manufacturing a linear motor capable of exerting high and stable performance, a linear motor, a stage apparatus equipped with the linear motor, and an exposure apparatus.
DISCLOSURE OF THE INVENTION
The invention according to a first aspect is a linear motor (R
1
) for allowing a movable body to move by its electromagnetic force, the linear motor (R
1
) comprising an armature coil (
23
), wherein the armature coil (
23
) comprises a plurality of coil bodies (
25
) and a frame (
24
) for holding these coil bodies (
25
) so as to array the coil bodies in one direction, and a positioning portion (
28
) for holding an end of each coil body (
25
) at a determined interval along the one direction formed in the frame (
24
).
With such a structure, the end of each coil body (
25
) is held by a groove (
28
) formed in the frame (
24
), whereby the plurality of coil bodies (
25
) are positioned at a determined interval.
In the linear motor (R
1
) described in the first aspect, the invention of a second aspect is characterized in that a notch (
31
) for passing a wire (C) of each coil body (
25
) therethrough is formed in the frame (
24
), and each coil body (
25
) is connected to one another in the outside of the frame (
24
).
As described above, the wire (C) of the coil body (
25
) is drawn out from the notch (
31
) to the outside of the frame (
24
), whereby connections of the coil bodies (
25
) of the same phase can be made outside the frame (
24
).
In the linear motor (R
1
) of the second aspect, the present invention of a third aspect of the present invention is characterized in that the notch (
31
) is formed so as to correspond to the positioning portion (
28
) formed in the frame (
24
), and a wire (C) from the end of the coil body (
25
) held by the positioning portion (
28
) is passe
Hayashi Yutaka
Tanaka Keiichi
Jones Judson H.
Nikon Corporation
Oliff & Berridg,e PLC
Ramirez Nestor
LandOfFree
Method of manufacturing linear motor, linear motor, stage... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of manufacturing linear motor, linear motor, stage..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of manufacturing linear motor, linear motor, stage... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2928950