JPH058413B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a linear light source device that forms ultraviolet light from a light source into an isolated line.

Conventionally, in order to expose a wafer using a mirror reflection type projection aligner, the ultraviolet rays generated from the ultra-high-pressure mercury lamp light source in the exposure optical system are made into a solitary line and imaged on a mask, and the ultraviolet rays are imaged on the wafer. I was going. In this case, the exposure energy that is imaged onto the wafer is not uniform over the entire length of the solitary beam, which affects the resolution of the pattern and requires a complicated adjustment device to solve this problem. A dot had appeared.

That is, in FIG. 1, ultraviolet light generated from an ultra-high-pressure mercury lamp light source 5 passes through a condenser lens 6, projects a light source image onto a slit plate 7 of a linear light source device 11, and then is transferred to a projection optical system by a lens 8. The image is projected onto a mask 4 within the device 10.

In the projection optical device 10, as shown in FIG. 2, the light on a point O of a circular arc-shaped ray (indicated by a dotted line) with a radius r ₀ that is imaged on the mask 4 is reflected by the concave mirror 1, and Next, the light is reflected by the convex mirror 2 and once more by the concave mirror 1, and then an image is formed on the wafer 3 at a 1:1 magnification. Similarly, an arc-shaped light beam (indicated by a dotted line) with radius r ₀ is imaged onto the wafer 3 . The entire surface of the wafer 3 is exposed by focusing the arc-shaped light beam on the wafer 3 and scanning the mask 4 and the wafer 3 in opposite directions shown by arrows A' and A.

As shown in FIG. 3, the slits 9 of the slit plate 7 of the linear light source device 11 are formed in the shape of circular arc lines with gaps of a constant width W, so that the ultraviolet light focused on the wafer 3 is also An arc-shaped ray of light having a constant width W is imaged. Now, as shown in FIG. 4, if the horizontal axis represents the longitudinal dimension of the arc-shaped light beam of the wafer 3, and the vertical axis represents the exposure energy E, the exposure energy E is not uniform and has a variation width σ. In addition, small values are shown at both ends of the wafer 3 in the longitudinal direction. Here, the exposure energy E is obtained by multiplying the illuminance of the ultraviolet light irradiated onto the wafer 3 by the time required to scan the wafer 3, etc., and is proportional to the illuminance of the ultraviolet light if the scanning time is constant.

As described above, if variations in the exposure energy E occur in the longitudinal direction of the arc-shaped light beam, a problem will arise that will affect the pattern resolution of the wafer 3.

The reason why the exposure energy E is not uniform is that the conventionally used ultra-high pressure mercury lamp light source 5
This is due to the fact that the lamp is formed of a long arc type, and the illuminance near the electrodes at both ends is insufficient, and the slit width 9 of the slit plate 7 is constant.

Therefore, conventionally, an adjustment means has been adopted in which the ultra-high pressure mercury lamp light source 5 is engaged with a linearly movable and rotatable position adjustment device, and the position of the light source 5 is adjusted to keep the illuminance distribution within a certain range. Was.
However, this method has disadvantages in that it takes time to adjust the illuminance, which not only reduces work efficiency but also requires skill in operation.

The present invention was devised to solve the above-mentioned drawbacks, and its purpose is to reduce variations in exposure energy in an exposure apparatus that projects a circuit pattern on a mask in the form of a solitary line and exposes it onto a substrate. In addition to ensuring that good resolution is obtained without
To provide a simple linear light source device which facilitates the adjustment work of a light source, improves work efficiency, and also ensures the adjustment work of the light source and improves the yield of products such as semiconductors.

In order to achieve the above object, the present invention provides a linear light source device that transforms light from a light source into an arcuate shape and forms an image on a mask in an exposure apparatus for projecting a circuit pattern on a mask and exposing it onto a substrate. In,
A female arcuate elastic member having a male arcuate member forming a male arcuate portion, and a female arcuate portion opposed to the male arcuate portion of the male arcuate member at a distance to form an arcuate slit space. and on one side forming the female arc-shaped portion of the female arc-shaped elastic member,
forming a plurality of notches extending in the direction in which the gap widens along the arc of the female arcuate portion to form a plurality of tongue-like portions on the female arcuate portion;
The other side of the female arc-shaped elastic member has a drive unit that rotates a threaded part that is screwed into a nut formed on the support base to reciprocate in the cutting direction, and A plurality of pressing means formed by being pivotally connected to the molded arc-shaped elastic member are arranged, and the driving portion of each pressing means is driven to rotate the threaded portion and reciprocate with respect to the support base. The structure is configured such that the distance between the arc-shaped slit spaces is changed by moving the part of the female arc-shaped elastic member having the tip thereof pivotally connected, and the simple structure ensures that
Moreover, the linear light source device is characterized in that the exposure energy on the substrate can be easily uniformized.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

First, the outline of the linear light source device 11 of the embodiment will be explained in the fifth section.
This will be explained using figures. A first elastic member 17 and a second elastic member 13 are provided on the base 18 . In this embodiment, the first elastic member 17 is of a fixed type, so it does not necessarily have to be made of an elastic body. An arc-shaped slit space 20 with a gap W is formed between the first elastic member 17 and the second elastic member 13. Moreover, the second elastic member 1
3, a large number of notches 21 are formed, and a large number of tongue-shaped portions 12 are formed. Further, a large number of pressing means 22 are attached to the base 18, and each pressing means 22
is engaged with the second elastic member 13. With the above configuration, when the pressing means 22 is reciprocated, the tongue portion at the position where the pressing means 22 acts and in the vicinity reciprocates, so that the gap W of the slit space 20 changes partially and smoothly. As described above, the gap W can be arbitrarily and minutely changed over the entire width of the slit space 20 in the longitudinal direction, and the number of ultraviolet rays passing therethrough can be increased or decreased.

Examples will be described in more detail below.

As shown in FIGS. 5 and 6, the base 18 is formed into a flat plate shape, and a long hole 18a having a width larger than a predetermined gap W through which ultraviolet rays pass is formed near the center thereof. . The base 18 has a first
An elastic member 17 is placed to cover one long side of the elongated hole 18a. In this embodiment, the first elastic member 17 is formed into a flat plate shape and is fixed on the base 18. Further, a male arc-shaped portion 17a is formed on one end side of the first elastic member 17, and as described above, the male arc-shaped portion 17a
It covers one long side of the long hole 18a.

Next, the second elastic member 13 is formed from an L-shaped elastic body, and one side of the L shape is provided on the base 18 and covers the other long side of the long hole 18a of the base 18. There is. At one end of this side, the male arc-shaped portion 17 is provided.
A female arc-shaped portion 13a having approximately the same radius as a is formed. The female arc-shaped portion 13a is provided with a gap W apart from the male arc-shaped portion 17a. Therefore, between the first elastic member 17 and the second elastic member 13, there is a circular arc line-shaped slit space 20 having a gap W.
will be formed.

Further, on the one side of the second elastic member 13, a large number of notches 21 are formed which extend in the direction in which the gap between the slit spaces 20 widens. Since the cuts 21 are formed at appropriate intervals along the arc of the female arc-shaped portion 13a, a large number of mutually adjacent tongue-shaped portions 12 are formed in the female arc-shaped portion 13a. Become. As shown in FIGS. 7 and 8, in order to actually create the tongue-shaped portion 12, first, as shown in FIG. Then, as shown in FIG. 8, the whole is formed into an arc shape. Therefore,
Depending on the width of the cuts 21, they may interfere with each other, so they are overlapped with each other to prevent interference.

Next, a plurality of pressing means 22 are engaged with the other side of the second elastic member 13 along its longitudinal direction. That is, the pressing means 22
, a threaded part 15 connected to the drive part 16 and reciprocated by the drive part 16, and a pin part 14 provided on the tip side of the threaded part 15.
The distal ends of the elastic members 4 are pivotally attached to one side of the second elastic member 13, respectively. Note that the screw portion 15 is attached to the base 1
It is threadedly engaged with and supported by the support stand 23 placed on the support base 8 .

Next, the operation of this embodiment will be explained.

As described above, the ultraviolet light passes through the gap W of the slit space 20 and is imaged on the mask 4. The exposure energy of the ultraviolet light after passing through is measured on the mask 4 over the longitudinal direction of the solitary light beam. Based on this measurement result, the drive section 16 of the pressing means 22 located near the position in the longitudinal direction corresponding to this measurement value is driven in a predetermined direction. As a result, the screw portion 15 moves in the required direction, and the pin portion 14 causes the second elastic member 13 to move. Since the second elastic member 13 is made of an elastic body and forms the tongue-shaped portion 12,
Only the vicinity of the location pressed by the pressing means 22 changes mainly. As a result, the gap W of the slit space 20 changes. As described above, it is possible to arbitrarily change the gap W between the slit spaces 20 at a plurality of locations, and it is possible to maintain uniform exposure energy. Furthermore, although the second elastic member 13 has a large number of tongue-shaped parts as described above, it is integrally continuous as a whole, and is made of an elastic material as described above. , the gap W can be adjusted continuously and smoothly over the entire length. As described above, the gap W ₁ on both ends of the slit space 20 can be made wider than the gap W ₂ in the center, and thereby the lack of illuminance at both ends of the ultra-high pressure mercury lamp light source 5 described above can be solved. As described above, a complicated position adjustment device or the like is not required.

Note that widening the gap W may cause astigmatism, resulting in a decrease in resolution.

However, the variation rate of exposure energy is about ±10%, and the rate of change of gap W ₁ with respect to gap W ₂ to make it uniform is less than a few percent, so the problem of astigmatism mentioned above can be ignored. be able to.

According to this example, the rate of change in exposure energy was less than ±2 to 3%, demonstrating a significant improvement over the conventional method.

In the above embodiment, the first elastic member 17 is of a fixed type, but this is used as the second elastic member 13, and the first and second elastic members 17, 1
3 may be used to finely adjust the gap W. Furthermore, although the second elastic member 13 is integrally L-shaped, it may be a combination of a plate-shaped member on which the tongue-shaped portion 12 is formed and a spring member that is engaged with the plate-shaped member in an L-shape. Further, the first and second elastic members may all be flat spring members, and a tongue-like portion may be formed thereon so as to change the curvature in the direction.

Further, the pressing means 22 is not limited to the above, of course.

As is clear from the above description, according to the present invention, the driving portion of each pressing means is driven to rotate the threaded portion to reciprocate with respect to the support base, and the tip of the threaded portion is pivotally attached. Since the gap between the arcuate slit spaces is changed by moving the female arcuate elastic member, the gap between the arcuate slit spaces can be reliably and easily adjusted using a simple configuration. As a result, the circuit pattern on the mask can be projected in an arcuate shape and exposed onto the substrate by making the exposure energy uniform, and the efficiency and reliability of the light source adjustment work can be improved. It used to be effective in improving the yield of products such as semiconductors.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram illustrating the exposure optical system of a conventional mirror reflection type projection aligner, Fig. 2 is a perspective view illustrating the projection optical system, Fig. 3 is a plan view showing the slit shape, and Fig. 4 The figure is a diagram showing the distribution of exposure energy in the longitudinal direction of the slit.
Fig. 5 is a perspective view showing the configuration of an embodiment of the present invention, Fig. 6 is a sectional view taken along the - line arrow in Fig. 5, and Figs. 7 and 8 illustrate the elastic members of the main parts of the embodiment. FIG. 3... Wafer, 4... Mask, 5... Ultra-high pressure mercury lamp light beam, 11... Linear light beam device, 12... Tongue-shaped part, 13... Second elastic member, 14... Pin part,
15...screw part, 16...drive part, 17...first
Elastic member, 18... Base, 20... Slit space, 21... Notch, 22... Pressing means, 23...
...Support stand.

Claims (1)

[Claims] 1. In a linear light source device that converts light from a light source into an arcuate shape and forms an image on the mask in an exposure device for projecting a circuit pattern on a mask and exposing it onto a substrate, a male type that forms a male arcuate portion is used. an arc-shaped member; and a female-type arc-shaped elastic member having a female-type arc-shaped part facing the male-type arc-shaped part of the male-type arc-shaped member with a gap therebetween to form an arc-shaped slit space; On one side of the elastic member forming the female arc, a large number of notches extending in the direction in which the gap widens are arranged along the arc of the female arc to form a large number of cuts in the female arc. The female arc-shaped elastic member has a drive portion on the other side thereof that rotates a threaded portion that is screwed into a nut formed on the support base to reciprocate in the cutting direction. , a plurality of pressing means formed by pivotally connecting the tip of the threaded portion to the female arc-shaped elastic member are arranged, and the driving portion of each pressing means is driven to rotate the threaded portion against the support base. A linear light source characterized in that the linear light source is configured such that the distance between the arc-shaped slit spaces is changed by reciprocating the female arc-shaped elastic member to which the tip of the threaded portion is pivotally connected. Device.