JPH04204946A - Exposing device - Google Patents

Abstract

PURPOSE:To decrease the weight of a lens, to reduce the cost of an entire device and to make a gap between a glass mask and a transfer member large by constituting a projection lens of the assembly of a specified rod lens. CONSTITUTION:Light emitted from a light source 1 is turned into the parallel rays of light by a condenser lens 2 to irradiate the glass mask 3, then the light in accordance with the projection pattern 3a of the mask 3 is allowed to pass through the projection lens 4 to irradiate a transfer member 5. Then, the rod lens 4a by which the light having refractive index distribution in a radial direction is bent is used as the lens 4, where many lenses 4a are regularly arranged. The gap between the lenses is filled with black silicone resin 4b so as to be attached, and the periphery of the lens is fixed with glass fabric base material epoxy resin black laminating plate 4c having nearly the same characteristic as the thermal expansion coefficient of the lens 4a.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an exposure apparatus, and more particularly to an exposure apparatus used in a photo process in the manufacturing process of electronic devices.

(Prior Art) In recent years, electronic devices such as contact line sensors, thermal heads, and LCDs have become increasingly dense and precise. The photo process is an important point.

In this photo process, various optical methods have been considered for transferring the projected pattern of the glass mask onto a transfer member attached to the surface of the electronic device, or for transferring the pattern.

For example, there are contact methods in which parallel light is irradiated with the glass mask and transfer member in close contact with each other, proximity methods in which the glass mask and transfer member are placed apart from each other, and lenses in which a lens is placed between the glass mask and the transfer member. There are projection methods that are set up and projected. This projection method includes a reflective projection method using mirrors and a reduction projection method (step-and-repeat) in which exposure is repeated by moving a stage.

On the other hand, recently, the minimum line width of patterns for electronic devices has been rapidly increasing to about several μm to 10 μm, or it is necessary to expose an extremely wide area.

In order to cope with this, the magnification of the reduction lens (projection lens) was set to 1 = 1, the aperture of the lens was increased, and the system was combined with a stepper or a very large mirror projection method to perform batch exposure. It has been devised.

(Problem to be solved by the invention) However, a projection lens or mirror lens with a magnification of 1.1 becomes extremely large and heavy. In order to firmly support something like this, a sturdy framework is of course necessary, and a vibration-proof stand with precision equipment is also required, which tends to make the equipment very expensive.

Furthermore, when combined with a stepper, screen splicing occurs, which becomes a problem when patterns such as LCDs and close-contact line sensors become increasingly high-definition.

That is, in the case of conventional LSIs, there is no particular problem because the screen is located at the edge of the screen, whereas for LCDs and contact line sensors, the screen is located near the center of the screen and is a problem. Further, in the stepper type, there is a problem that the throughput is lower than that in the case of batch exposure because two or more shots are exposed.

In addition, pro-mixi type exposure equipment exposes the glass mask and the transfer member all at once with a certain narrow gap between them, so it is very cheap in terms of price, or if the area of the transfer member becomes large. It is said that the distance between the glass mask and the transfer member can only be narrowed to about 30 μm due to warpage, waviness, non-parallelism, etc. of the transfer member, and the resolution is said to be at the limit of about 7 μm. Also, during mass production, increase throughput,
Since it is necessary to prevent dust (particles) from getting caught between the gaps, it is necessary to further widen the gap distance, and the resolution usually drops to 20 μm or more.

Furthermore, the contact method requires that the glass mask be considered a consumable item, which poses too many problems for production equipment.

The present invention was invented in view of the problems of the conventional devices, and an object of the present invention is to provide an exposure device equipped with a projection lens that is inexpensive, lightweight, and capable of increasing the area. .

(Means for Solving the Problems) According to the present invention, a projection lens is provided between a glass mask on which a projection pattern is formed and a transfer member that is irradiated with light from a light source along the projection pattern of the glass mask. There is provided an exposure apparatus characterized in that the projection lens is constituted by an assembly of a large number of rod lenses having a magnification of 1:1 and a refractive index distribution in the radial direction. This achieves the above objectives.

(Function) By configuring as described above, the weight of the projection lens can be reduced while using the projection method as is, and the cost of the entire device can be reduced by simplifying the vibration isolation table. .

In addition, by inserting the above-mentioned rod lens assembly between the glass mask and the transfer member of a proximity type exposure device, it is possible to increase the gap between the glass mask and the transfer member, and it is possible to increase the gap between the glass mask and the transfer member. Eliminates contamination of the glass mask due to build-up and resist adhesion.

Furthermore, since the depth of focus can be set to ±50 μm or more, it is possible to prevent the resolution from decreasing even if the substrate warps, undulates, unevenly, tilts, etc. within 100 μm.

(Example) Hereinafter, the present invention will be explained in detail based on the accompanying drawings.

FIG. 1 is a schematic diagram showing an embodiment of an exposure apparatus according to the present invention, in which 1 is a light source, 2 is a condenser lens, 3 is a glass mask, 4 is a projection lens, and 5 is a transfer member.

As the light source 1, for example, light having a wavelength of 350 to 450 nm is used.

The condenser lens 2 is provided to convert light from a light source into parallel light rays.

As the glass mask 3, a glass substrate or a quartz substrate having a low thermal expansion coefficient of, for example, 5 ppm or less and a planar unevenness of 2 to 5 μm or less is used, and the drawing of the chip was repeated while reducing the size to, for example, 1/10. It is later developed and formed to form a projection pattern 3a. This projection pattern 3a must be formed, for example, from an emulsion ultrafine particle glue Tubman emulsion or a low reflection chromium film, but in any case must have a remarkable blocking property against the sensitive wavelength.

As the projection lens 4, as shown in FIG. 2, a rod lens 4a having a refractive index distribution in the radial direction so that light can be bent is used, and a large number of rod lenses 4a are arranged regularly and precisely. black silicone resin 4b to prevent flare in the lens gap.
etc. and adhered to each other, and the periphery is fixed with a glass cloth base epoxy resin black laminate 4c having characteristics almost the same as the coefficient of thermal expansion of the lens. The area of the rod lens assembly may be a desired area corresponding to the transfer member. As each rod lens body 4a, the g-line (436
It is preferable to use light with a resolving power of about 5 to 30 μm, a depth of focus of about ±20 to 50 μm, and a brightness unevenness of about ±5% using light in the vicinity of nm). Such rod lenses are currently sold by Nippon Sheet Glass Co., Ltd. as the SLΔ9 series.

The transfer member 5 is, for example, a substrate for a contact licensor, L
It can be arbitrarily selected from CD substrates, thermal head substrates, etc. The substrates of such electronic devices are made of glass, ceramics, bulk semiconductors, etc., and a thin metal film such as aluminum is deposited on almost the entire surface of the substrate. It is coated with a photosensitive material (resist) that can be easily removed. When used as a negative resist, a resist containing polyisoprene as a main component is used, and when used as a positive resist, a combination of quinonediato and noholac resin is used.

In the exposure apparatus according to the present invention, the light emitted from the light source 1 is converted into parallel light by the condenser lens 2 and is irradiated onto the glass mask 3, and the light according to the projection pattern of the glass mask 3 passes through the projection lens 4. is irradiated onto the transfer member.

(Effects of the Invention) As described above, according to the exposure apparatus according to the present invention, since the projection lens is constituted by an assembly of a large number of rod lenses having a magnification of 1 and having a refractive index distribution in the radial direction, the projection lens is It is possible to reduce the weight of the projection lens while using the same method,
By simplifying the frame structural material and the vibration isolating table, the cost of the entire device can be reduced.

In addition, by inserting the above-mentioned rod lens assembly between the glass mask and the transfer member of a proximity type exposure device, it is possible to increase the gap between the glass mask and the transfer member, and it is possible to increase the gap between the glass mask and the transfer member. Eliminates contamination of the glass mask due to build-up and resist adhesion.

Furthermore, since the depth of focus can be increased to ±50 μm or more, the resolution will not deteriorate even if the substrate is warped, undulated, uneven, tilted, etc. as long as it is within 100 μm.

Therefore, contact type image sensor, thermal end, L
It is ideal as an exposure device that precisely exposes large areas of electronic devices such as CDs at once.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of an exposure apparatus according to the present invention, and FIG. 2 is an enlarged view of a projection lens. 1. Light source 2. Condenser lens 3, Glass mask 4, Projection lens 5, Transfer member

Claims (1)

[Claims] In an exposure apparatus comprising a projection lens disposed between a glass mask on which a projection pattern is formed and a transfer member onto which light from a light source is irradiated along the projection pattern of the glass mask, the projection lens has a magnification. An exposure apparatus comprising an assembly of a large number of rod lenses having a 1:1 refractive index distribution in the radial direction.