KR20010105870A - Phase shift mask - Google Patents

Abstract

The present invention relates to coating compositions comprising busoxinone which are capable of forming a coating film having excellent antifouling performance and being capable of providing such excellent performance for a long period of time. The invention further relates to a method for protecting surfaces or objects in frequent or constant contact with water.

Description

Phase shift mask

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase shift mask, and more particularly, to a phase shift mask for selectively increasing a resolution in a weak part of a photo process to secure a stable process margin of a photo process.

In general, in accordance with the trend of high integration of memory integrated circuits, technology development has been conducted in the direction of minimizing the size of the micropattern of each device constituting the integrated circuit as much as possible. As an example, when a conventional chromium (Cr) mask is applied to a photo process to form a fine pattern such as a contact hole, a portion of the photoresist film is likely to remain at the edge of the bottom surface of the opening of the photoresist film, thereby securing a margin of the photo process. It is difficult to further reduce the size of the contact hole. To solve this problem, instead of the conventional chrome mask, a phase shift mask was used for the photo process. This is because the phase inversion mask has superior effects such as improvement of depth of focus, resolution and reduction of exposure energy compared to the chrome mask, which is advantageous for forming a contact hole of a fine pattern.

The phase shift mask according to the prior art is configured as shown in Figs. That is, as illustrated in FIG. 1, patterns 11 and 13 for a word line of a DRAM, for example, are formed in a line / space shape on the substrate 10 made of a transparent quality material. Also, as shown in FIG. 2, patterns 21, 23, and 25 for bit lines, for example, are formed in a line / space on the substrate 10. As shown in the cross-sectional view of FIG. 3, all of the patterns 21, 23, and 25 on the substrate 10 are formed of the molybdenum silicide layer 27 having 180 ° phase inversion and 8% light transmittance. It consists of a single layer and can be adjusted to a specific thickness for this purpose. Of course, since the patterns 11 and 13 on the substrate 10 are also the same, description thereof will be omitted for the convenience of description in order to avoid duplication of description.

However, the conventional phase inversion mask is a Levenson type, and the patterns 11 and 13 are not in the same line / space form, and similarly, the patterns 21, 23 and 25 are also the same line / Since it is not a space type, resolution is inevitably different. The weak part of the pattern, such as the narrow part of the pattern or the narrow part of the gap, is particularly problematic in the photo process. That is, the sidelobe phenomenon in which patterns are formed where they are not desired when the bias of the patterns is not optimized or defocused or when the patterns are gathered due to the inversion of the light transmittance of 8% around the patterns This is highly likely to occur, and it is difficult to secure stable margins in the photo process in the manufacture of semiconductor devices, which have become highly integrated at present. Accordingly, there is an urgent need for a new phase inversion mask that can solve the phase conflict problem caused by applying the Levenson type phase inversion mask to the line / space pattern.

Accordingly, an object of the present invention is to provide a phase inversion mask to improve the integration degree of a semiconductor device by securing a stable margin of the photo process.

1 is a pattern diagram showing a main part of a word line of a DRAM formed in a phase inversion mask of the prior art;

Figure 2 is a pattern diagram showing the main portion of the bit line of the DRAM formed in the phase inversion mask of the prior art.

3 is a cross-sectional view taken along the line A-A of FIG.

Fig. 4 is a pattern diagram showing the main part of the word line of the DRAM formed in the phase inversion mask of the prior art.

5 is a pattern diagram showing a main portion of a bit line of a DRAM formed in a phase inversion mask according to the present invention;

6 is a cross-sectional view taken along line B-B of FIG. 5.

Phase inversion mask according to the present invention for achieving the above object is

Translucent substrate;

Patterns of the phase inversion layer, each formed on a portion of the substrate; And

And a layer for increasing resolution, formed on a portion of the patterns.

Preferably, the layer for increasing the resolution may be made of a light blocking layer such as a chromium layer. The transmittance at a portion of the pattern may be chosen to be at least 8%.

Therefore, the phase inversion mask of the present invention selectively forms a chromium layer for increasing the resolution in a weak pitch of narrow patterns, thereby increasing the resolution of the weak portion, thereby preventing side lobe phenomenon and further improving the fine pattern such as contact hole. The margin of the photo process for forming can be secured.

Hereinafter, a phase inversion mask according to the present invention will be described in detail with reference to the accompanying drawings. The same code | symbol is attached | subjected to the same structure and the same operation | work part as a conventional part.

Figure 4 is a pattern diagram showing the main portion of the word line of the DRAM formed on the phase inversion mask according to the present invention, Figure 5 is a pattern diagram showing the main portion of the bit line of the DRAM formed on the phase inversion mask according to the present invention, Figure 6 It is sectional drawing cut along the BB line of 5. For convenience of description, it will be described with reference to FIGS. 4 to 6.

Referring to FIG. 4, the patterns 31 and 33 for the word line of the DRAM, for example, are similar to the patterns 11 and 13 of FIG. 1. It is formed in the form of a space.

Referring to FIGS. 5 and 6, patterns 41, 43, and 35 for the bit line of the DRAM are, for example, the patterns 21 of FIG. Similar to (23) and (25), they are formed in a line / space form. In addition, the entirety of the patterns 31 and 33 is composed of a phase inversion layer, and the pitch of the pattern is sporadically narrowed due to the characteristics of the device, that is, the portions 42 of the patterns 41, 43, and 35. Layers 44, 46 are further formed to increase the resolution. In more detail, the entire lower layer of the patterns 41, 43, and 45 is formed of a molybdenum silicide layer as the phase inversion layer 27 having the characteristics of 180 degree phase inversion and 8% light transmittance. On the portions 42, 44, and 46 of the patterns 41, 43, and 35, which are fragile portions of the photo process, which are difficult to secure a margin of the photo process. A chromium layer is further formed. Of course, although the cross-sectional view of FIG. 4 is not shown, the entire lower layer of the patterns 31 and 33 is composed of a molybdenum silicide layer as a phase inversion layer, and the pattern 33 is a weak part that is difficult to secure a margin of a photo process. It is apparent that a layer of chromium is laminated on the portion 34 to increase the resolution.

On the other hand, the transmittance of the phase inversion layer can be selected to 8% or more by adjusting the thickness of the phase inversion layer in order to obtain a desired resolution in the weak spot.

When the phase inversion mask configured as described above is applied to a photo process for manufacturing a semiconductor device, patterns 41 and 43 formed of a weak part, for example, a phase inversion layer 27, which are difficult to secure a margin of the photo process. The chromium layer, which is a light blocking layer 37, is selectively formed only on portions 42, 44, and 46 of), 35, so that the resolution at these portions 42, 44, 46 is patterned. It is relatively higher than the rest of them.

Therefore, in the present invention, unlike the conventional phase inversion mask, due to the characteristic that the pitch is narrowed sporadically due to the characteristics of the semiconductor device, the patterns may be undesired in the case where the bias of the patterns is not appropriate or when defocusing or when the patterns are concentrated on the layout. It is possible to prevent the side lobe from being formed and further secure a stable margin of the photo process.

In addition, the phase inversion mask of the present invention is actually applied to the production of fine patterns, such as contact holes of ultra-high density semiconductor devices, because there is no phase collision that is a problem when the conventional Levenson type phase inversion mask is applied to the line / space pattern. Most likely.

As described above, the phase shift mask according to the present invention forms patterns of the phase shift layer on the substrate and forms a light blocking layer for improving the resolution on the weak portions of the patterns having a narrow pitch in the photo process.

Therefore, the present invention can prevent side lobe phenomenon in the weak part of the photo process, ensure a stable margin of the photo process, and further improve the integration degree of the semiconductor device.

On the other hand, the present invention is not limited to the contents described in the drawings and detailed description, it is obvious to those skilled in the art that various modifications can be made without departing from the spirit of the invention. .

Claims (3)

Translucent substrate; Patterns of the phase inversion layer, each formed on a portion of the substrate; And And a layer for increasing resolution formed on a portion of the patterns. The phase shift mask of claim 1, wherein the layer for increasing the resolution comprises a light blocking layer. The phase shift mask according to claim 2, wherein the light blocking layer is formed of a chromium layer.