JPH05198477A - Exposure apparatus and manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To form a fine resist pattern by photolithography. CONSTITUTION:On the occasion of exposing a fine pattern on a photoresist through a photomask, the pattern is divided into two photomasks 13 and 14. A phase shift film is formed on the entire part of the one photomask 14, images of two photomasks 14 are optically aligned and these are simultaneously exposed on the same position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus used for manufacturing a semiconductor device and the like and a method for manufacturing the semiconductor device.

[0002]

2. Description of the Related Art A schematic view of a conventional exposure apparatus is shown in FIGS.
Shown in. The light emitted from the light source 1 passes through the photomask provided with the phase shift film 2 and reaches the wafer 4 through the reduction lens system 3. At that time, when the light passes through the phase shift mask composed of the glass element 5, the chrome pattern 6 and the phase shift film 7 in FIG. 4, the amplitude of the light varies depending on whether the phase shift film is present or not. Thus, the amplitudes are reversed, and as a result, the light intensity is as shown by 9 in FIG.

[0003]

However, the conventional method requires a phase shift mask having a complicated structure as described above, and it is difficult to form a phase shift film in the phase shift mask. However, there are many problems such as a method for inspecting defects of the phase shift film has not been established yet.

Therefore, the present invention has an exposure method having an exposure method capable of forming a fine pattern of the same level as in the case of using a conventional phase shift mask without requiring a phase shift mask having a complicated structure. The purpose is to provide a device.

[0005]

In order to solve the above problems, the exposure apparatus of the present invention arranges every other adjacent pattern when exposing a fine pattern to a resist.
It is divided into two photomasks, a film that changes the phase by half a wavelength is attached to one of the photomasks, and light from the same light source is applied to the two photomasks. It is characterized in that the pattern of two photomasks is simultaneously exposed at the same place on the object.

A method of manufacturing a semiconductor device using the above-mentioned exposure apparatus.

[0007]

EXAMPLE An example of the present invention is shown in FIGS.

FIG. 1 is a schematic view of an exposure apparatus of the present invention.
Reference numeral 10 is a light source, 11 and 12 are mirrors for collecting light from the light source and further guiding the light to two photomasks, 13 is a photomask, 14 is a photomask with a phase shift film,
15 and 16 are reduction lens systems, and 17, 18 and 19 are 2
Mirror to guide the two reduced lights to the same place on the wafer,
20 is a wafer with a resist.

The light collected by the light source 10 is guided to the photomask 13 and the photomask 14 with the phase shift film, and the light passing through the photomask 14 with the phase shift film is the photomask 13 due to the phase shift film. The light has a phase opposite to that of the light passing therethrough, and further passes through the reduction optical system and is collected by the mirror 19 via the mirrors 17 and 18, where the pattern is synthesized and hits the wafer 20.

FIG. 2 shows the photomask used here and the amplitude and intensity of light. Reference numerals 21 and 23 are plain glass, 22 and 24 are chrome surfaces, 25 is a phase shift film, 26 is the amplitude of the synthesized light, and 27 is the intensity of the synthesized light.

First, the photomask has a fine pattern of 1
Then, patterning is performed by dividing into two photomasks. After that, a phase shift film is formed on either one of the photomasks, and light is applied to the photomask by the exposure apparatus of the optical system as shown in FIG.
It becomes the amplitude like. That is, the light synthesized by such two photomasks has exactly the same amplitude as the light obtained by the conventional phase shift mask technique. Therefore, the intensity of light that reaches the wafer becomes 27,
It is possible to form a pattern that is exactly the same as when performing exposure using a conventional phase shift mask.

What is important here is that when the 25 phase shift films are formed, it is not necessary to pattern the phase shift film itself unlike the conventional phase shift mask, and the phase shift film is formed over the entire photomask. The point is that you only have to do it. Patterning the phase shift film as in the past not only increases the number of photomask manufacturing steps, but also the method of forming itself is not easy, and the reduction in yield due to pattern defects in the phase shift film is avoided. Absent.
Not only that, there are still many problems such as the method for inspecting the phase shift film for defects is not yet established. However, the method of forming a phase shift film on the entire photomask is not only easy to form, but also almost completely avoids the occurrence of defects in the phase shift film. It is possible to easily perform it by applying the foreign matter inspection device used.

Although one embodiment of the present invention has been described above, the present invention is also applicable to those in which the phase shift film of the photomask is formed on the glass surface side instead of the pattern surface side of the photomask.

[0014]

As described above, when the photolithography process is performed by using the exposure apparatus of the present invention, it is possible to use a phase shift mask which has a complicated structure and is difficult to manufacture as in the prior art.
By using a photomask with a phase shift film that is easy to manufacture, there is an effect that a fine pattern similar to that of a conventional phase shift mask can be formed.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an exposure apparatus of the present invention.

FIG. 2 is a structural diagram of a photomask used in the present invention, and a phase and intensity distribution diagram of light when exposed by the exposure apparatus of the present invention.

FIG. 3 is a schematic view of a conventional exposure apparatus.

FIG. 4 is a structural diagram of a conventional phase shift mask and a phase and intensity distribution diagram of light when exposed by a conventional exposure apparatus.

[Explanation of symbols]

 1 ... light source 2 ... phase shift mask 3 ... reduction lens system 4 ... wafer 5 ... glass element 6 ... chrome pattern 7 ... phase shift film 8 ... light amplitude 9 ... light intensity 10 ... Light source 11 Mirror 12 Mirror 13 Photomask 14 Photomask 14 Photomask with phase shift film 15 Reduction lens system 16 Reduction lens system 17 Mirror 18 Mirror 19 Mirror 20 Wafer 21 Glass element 22 Chromium surface 23 Glass element 24 Chrome layer 25 Phase shift film 26 Light amplitude 27 Light intensity

Claims (2)

[Claims] 1. An exposure apparatus used for manufacturing a semiconductor device, etc., when exposing a fine pattern to a resist,
The adjacent patterns are divided into two photomasks arranged alternately, and a film for changing the phase by half a wavelength is attached to one of the photomasks. An exposure apparatus that simultaneously exposes an object such as a wafer with patterns of two photomasks at the same location through various mirror systems. 2. A method of manufacturing a semiconductor device, wherein the exposure apparatus according to claim 1 is used.