JPH0749457Y2 - Laser mirror mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a mounting structure of a position measuring laser mirror on a stage in, for example, an electron beam drawing apparatus.

(Prior Art) Conventionally, a mounting structure of a position measuring laser mirror provided on a stage of an electron beam drawing apparatus, a stepper, a mask defect inspection apparatus, etc. is as shown in FIG. 3 and FIG. .

That is, the lower surfaces of both ends of the laser mirror 1 are supported by the mounting portion 3 and the receiving portion 4 formed on the upper surface side of the mirror base 2, and the other end portion of the laser mirror 1 is adhered to the mounting portion 3 to form one end. The part is adhesively fixed to the adhesive part 6 of the fixture 5. The fixture 5 is fixed to the mirror base 2 with bolts 7,7.

The upper surfaces of the mounting portion 3 and the receiving portion 4 formed on the upper surface of the mirror base 2, that is, the portions in contact with the lower surface of the laser mirror 1 are processed with good flatness.

After the laser mirror 1 is adhered to the mirror base 2 as described above, the mirror base 2 and the stage 8 are fixed to the stage 8 with bolts 9 and 9.

The stage 8 is adapted to be driven in a direction indicated by an arrow X and a direction Y as shown in FIG. 4 by a drive device (not shown), and two laser mirrors for measuring the X direction position and the Y direction position. 1,1 will be installed.

In addition, 10 and 10 shown in FIG. 4 are laser beams for measurement.

Then, due to the difference in the coefficient of thermal expansion between the laser mirror 1 generally made of quartz and the mirror base 2 made of another material, the laser mirror 1 is changed due to the temperature change after the adhesive fixing.
When a difference in length occurs between the mirror base 2 and the mirror base 2, the difference is absorbed by the elastic deformation of the fixture 5 to prevent the laser mirror 1 from being adversely affected.

(Problems to be solved by the invention) However, even in such a conventional example, depending on the processing accuracy of the mounting surface of the mirror base 2 on the stage 8 and the processing accuracy of the mounting surface of the mirror base 2 of the stage 8, the bolt 9, When fixing with 9, unnecessary force is applied to the attachment part 3 or the adhesion part 6 of the attachment 5, and the plane of the laser mirror 1 is made to have a wavelength of λ / 20 to λ / 30 (processing accuracy when used alone). There was a problem that the degree was reduced to about λ / 10 to λ / 20. For this reason, conventionally, there has been a problem that it is necessary to improve the processing accuracy of each member and to perform the work with sufficient care at the time of adhesive attachment, which requires time and cost.

The present invention has been made based on the above circumstances, and an object of the present invention is to easily and surely without impairing the flatness of a laser mirror whose flatness is processed with high accuracy, though having a simple structure. It is intended to provide a mounting structure for a laser mirror that can be mounted.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention supports the lower surface of the laser mirror by a plurality of receiving portions to perform vertical positioning, and One end of the laser mirror in the longitudinal direction is adhered to the first fixture that has low rigidity in the vertical direction and high rigidity in the width direction, and the other end of the laser mirror has low rigidity in the longitudinal direction of the laser mirror and rigidity in the width direction. And a second mounting fixture having a high height, and these first and second mounting fixtures are mounted on the stage directly or through a member.

(Effect) That is, by adopting the above-described configuration, the present invention reduces the flatness of the laser mirror even if a temperature change occurs after mounting and a difference in length occurs between the laser mirror and the mirror base. Without this, accurate mounting is possible. Also, when mounting, even if the mirror base is deformed due to processing errors on the respective mounting surfaces of the mirror base and stage, the deformation is absorbed by the elastic deformation of the mounting tool, and there is almost no effect on the laser mirror. Workability can be improved.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is a laser mirror, 2 is a mirror base, and 8 is a stage.

The laser mirror 1 is in a state of being vertically positioned by supporting the lower surfaces of both ends of the laser mirror 1 by three receiving portions 15 ... Protrudingly provided on the upper surface of the mirror base 2.

Further, both ends of the laser mirror 1 in the longitudinal direction are attached to the mirror base 2
It is in a state of being held by the first and second fixtures 16 and 17 fixed to.

The first fixture 16 has a low rigidity in the vertical direction and a high rigidity in the horizontal direction (the direction in which the position is measured by the laser mirror), and its width direction (orthogonal to the direction in which the position is measured by the laser mirror). The end face of the laser mirror 1 is adhered and fixed via two adhesive parts 18, 18 protruding in the direction of (1). It should be noted that the downward pressing force of the laser mirror 1 by the first fixture 16 in the bonded state is substantially zero.

The second mounting member 17 has low rigidity in the longitudinal direction of the laser mirror 1 and high rigidity in the width direction, and
The end surface of the laser mirror 1 is adhered and fixed via a single adhesive portion 19 provided in a substantially central portion in the width direction.

The longitudinal pressing force of the laser fixture 1 by the second mounting tool 17 in the bonded state is also substantially zero.

That is, the first and second fixtures 16 and 17 hold the laser mirror 1 in a state in which an external force is not applied as much as possible.

The first and second fixtures 16 and 17 are fixed to the mirror base 2 with two bolts 7 and 7, respectively, and each end of the mirror base 2 has one bolt. It is fixed to the stage 8 at 9.

Further, the pitch of the receiving portions 15 of the mirror base 2 in the longitudinal direction has a dimension called a Bessel point or Airy point where the deflection is smallest with respect to the length of the laser mirror 1.

With the above configuration, even if a temperature change occurs after mounting and a difference in length occurs between the laser mirror 1 and the mirror base 2, the flatness of the laser mirror 1 is not reduced, and When mounting, even if the mirror base 2 is deformed due to processing errors of the respective mounting surfaces of the mirror base 2 and the stage 8, the deformation is absorbed by the elastic deformation of the first mounting fixture 16 or the second mounting fixture 17. As a result, the laser mirror 1 is hardly affected, and therefore the flatness does not decrease.

Further, by making the heights of the adhesive portions of the first and second fixtures 16 and 17 to the laser mirror 1 substantially the same, the moment due to the external force applied to the end surface of the laser mirror 1 is not generated, and the flatness is further reduced. Hard to do.

That is, it is possible to easily and surely attach the laser mirror 1 whose flatness is processed with high precision, without impairing the flatness even though it has a simple structure.

In addition, in the above-described embodiment, the first and second fixtures 16 and 17 are used.
However, the present invention is not limited to this, and may be directly attached to the stage 8.

Of course, the present invention can be variously modified without departing from the spirit of the present invention.

In the description of the present invention, the same parts as those in the above-described conventional example are designated by the same reference numerals, and detailed description thereof will be partially omitted.

[Effects of the Invention] As described above, according to the present invention, it is possible to easily and surely attach a laser mirror whose flatness is machined with high precision, without reducing the flatness as much as possible even though it has a simple structure. It is possible to provide a mounting structure for a laser mirror that can be used.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention.
FIG. 1 is a schematic vertical sectional side view showing a mounted state, FIG. 2 is a schematic plan view of the same, FIGS. 3 and 4 show a conventional example, and FIG. 3 is a schematic vertical sectional view showing a mounted state. FIG. 4 is a side view and FIG. 4 is a schematic plan view showing an arrangement state of the laser mirror with respect to the stage. 1 ... Laser mirror, 2 ... Mirror stand, 8 ... Stage, 15 ...
Receiving part, 16 ... First fixture, 17 ... Second fixture, 18, 19 ...
Adhesive part.

Claims (4)

[Scope of utility model registration request] 1. A laser mirror mounting structure for mounting and fixing a laser mirror mounted on a stage, comprising: a plurality of receiving portions for supporting a lower surface of the laser mirror for vertically positioning the laser mirror; A first fixture having an adhesive portion for adhesively fixing one end in the longitudinal direction of the laser mirror supported by the receiving portion and attached to the stage directly or through a member, and the other end in the longitudinal direction of the laser mirror. A second mounting member having a bonding portion for bonding and fixing and mounted directly or through a member to the stage, wherein the first mounting member has a low rigidity in the vertical direction of the laser mirror and a rigidity in the width direction. High structure, second
The mounting structure of the laser mirror is characterized in that the mounting tool has low rigidity in the longitudinal direction of the laser mirror and high rigidity in the width direction. 2. The utility model registration as claimed in claim 1, wherein the first fixture is for fixing two end portions of the end face of the laser mirror in the width direction by adhesive bonding. Mounting structure. 3. A laser mirror according to claim 1, characterized in that the second fixture is for fixing one end in the width direction of the end face of the laser mirror by adhesion. Mounting structure. 4. The mounting of a laser mirror according to claim 1, wherein the adhesive part of the first fixture and the adhesive part of the second fixture have substantially the same height. Construction.