JPS5854494B2 - Pattern design information - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Conventionally, a photosensitive member SO has been used in which a diffusive metal is laminated on two layers of chalcogen glass.

The photosensitive property of this photosensitive member is the diffusion of light into the metal chalcogen glass layer.

The diffused metal acts to make the chalcogen glass layer insoluble in alkali.

This makes the difference in alkali solubility between the unexposed area and the exposed area of the chalcogen/glass layer noticeable, thereby providing high resolution in pattern formation by alkali etching.

The diffusion of the metal into the chalcogen glass is accompanied by the relative diffusion of the chalcogen glass into the metal, and as a result mutual diffusion occurs between the diffusive metal layer and the chalcogen glass layer, resulting in the formation of foreign substances in the exposed area. It is observed that a diffusion region is formed.

This diffusion part is a mixed part of metal and chalcogen glass.

On the other hand, the diffusion effect of metals has diversified the applications of photosensitive elements.

This is because the electrical properties of the diffusion region are superior to those of the chalcogen glass layer in terms of various properties such as electrical resistance, photoconductivity, photovoltaicity, and electrical resistance voltage dependence (so-called winching phenomenon or memory phenomenon). This is because not only are they vastly different, but also, as mentioned above, changes in chemical properties such as acid resistance and alkali elution, and σ-thermal properties such as optical density and crystallinity are also vastly different.

These differences in fiber characteristics are utilized as various pattern members to be described later.

For example, the optical density of the diffuser for visible light is
Its electrical resistance value, which is between that of metals and chalcogen glass, is used for micro-photographs, photomasks, etc., and its electrical resistance, which is between that of metals and chalcogen glass, is used for electrical circuit components. In addition, it is used as a hologram by taking advantage of the differences in optical refractive index, optical transmittance, and optical density between metal and chalcogen glass.

The most typical pattern member formation process for photosensitive members expected to have many uses is, after pattern exposure,
This is a process in which the residual diffusible metal layer that did not contribute to diffusion is removed, or if necessary, the unexposed chalcogen glass layer is removed.

Removal of the residual diffusible metal is carried out primarily to further increase the pattern contrast of the pattern member formed by the fixing process and pattern exposure to eliminate photosensitivity to subsequent light irradiation.

Removal of the remaining diffusible metal layer is usually carried out by dissolution with an acidic solution.

It is desirable that the remaining diffusive metal layer be removed as completely as possible from the viewpoint of pattern sharpness, resolution, and fixing effect.

If the pattern to be formed is not a fine pattern but a relatively thick pattern, the remaining diffusive metal layer Q1
The end point of solution removal can be confirmed by inspection, but in the case of fine patterns, it is not easy to confirm the end point.

Especially when there is a diffusive metal layer remaining in the exposed area,
This is even more difficult due to the large optical density of the diffuser.

For this reason, it is often found that after the removal process of the remaining diffusive metal layer, thin layers or flakes of the remaining diffusive metal layer remain that have not been completely removed.

Such unremoved thin layers or flakes not only impair the sharpness and resolution of the pattern, but also affect the stability of the pattern and, if necessary, the dissolution and removal of the chalcogen glass layer. This prevents uniform and complete removal of the chalcogen glass layer.

Accordingly, the present invention provides a pattern member for forming a clear pattern member by effectively treating thin layers or flakes of the residual diffusible metal layer that have not been removed by dissolving and removing the residual diffusible metal layer. The main purpose is to provide a formation method.

The purpose of the present invention is to dissolve and remove the residual diffusive metal layer by exposing the entire surface to light after dissolving and removing the residual diffusible metal layer, that is, by exposing the photosensitive member to pattern light, and then dissolving the residual diffusive metal layer that did not contribute to diffusion. This is accomplished by removing and then subjecting the entire surface to light exposure.

The full surface exposure, like the pattern exposure, is performed with light that diffuses the metal of the diffusive metal layer into the chalcogen glass layer.

By exposing the entire surface to light, the thin layer or flake of the residual metal layer that could not be removed after the removal of the residual diffusive metal layer is completely diffused into the chalcogen glass layer or the diffusion part, and the unremoved residual diffusive metal can cause harmful effects. It eliminates the

Next, the present invention will be further explained with reference to the drawings.

A typical configuration of the photosensitive member used in the present invention is shown in FIG.

3 is a support, 2 is a chalcogen glass layer, and 1 is a diffusible metal layer.

The chalcogen glass referred to in the present invention is a glass-like substance containing at least one of chalcogen elements, sulfur (S), selenium (Se), and tellurium (Te) as a main component. It is a type of glass.

Representative examples that are effective in the present invention include simple As-8 systems such as S, Se, As-8e systems, As-Te systems, and 5-8e systems.
system, 5b-8e system, 5b-Te system, 5i-8 system, B1-
These are binary chalcogen glasses such as 8e series and B1-Te series, or ternary chalcogen glasses such as As5Te series and As5e-Te series.

When forming a chalcogen glass layer, it is also effective to add a small amount (1 molar or less) of elements such as halogen, Ge, Si, T7, etc. as an activator, if necessary.

However, adding a small amount of metal as an additive is effective in terms of photosensitivity.

Typical metals to add are A g m C
u s Z n zCd, MrbGa, In, BL S
b, i or their alloys, especially Ag and Cu
is suitable.

The amount of metal added is 10, the number of atoms that make up chalcogen glass.
0, the number of atoms is 1 to 0.0001, especially 0.5 to 0.
005 is preferred.

The thickness of the chalcogen glass layer is set appropriately depending on the application, but it can be applied to photomasks, various high-density circuit members that utilize the difference in electrical properties between the image area and the non-image area of the pattern to be formed, and the difference in optical density. In order to obtain a high-resolution pattern such as a micro-photograph using , the chalcogen glass layer is usually set to be thin, about 1000 mμ to 10 mμ.

In particular, in order to obtain resolution of 2 μ or more, the distance is approximately 500 m.
It is set to μ~50mμ.

The lower limit of the layer thickness range is defined by manufacturing limitations for forming a uniform layer.

When molten chalcogen glass is applied, the thickness is several μm4.
t, a thickness of 100μ is easy to obtain, and when cut out as a wafer, the thickness is 10μ or more.

A diffusible metal layer is defined as a layer that provides a metal that can diffuse into the chalcogen glass layer upon irradiation with light.

Metals that can be diffused include all kinds of metals, and representative metals from the viewpoint of practicality include Li and Nap K.

Alkali metals such as Rb and C3, Be*Mg, Ca.

Sr, and alkaline earth metals such as Bas, Ag.

Zn, Cd, Mn, Ga, Ni, Cr, Cu, Int
These are metals such as Sn and T1, and compounds that dissociate and generate these metals or metal ions.

Suitable examples of these compounds include metal sulfides,
These include selenides, tellurides, oxides, and loge/oxides.

As specific examples of these, a particularly favorable compound is Cu2S
yAg2S*Ag2Se,Ag2Te
.

ZnO, SrF 5CaF2. KCL LiBr, Li
ct+LiF, LiL NaC1, AgleAgBr,
AgNO3.

P b I 2 # KAg4 L 5 t RbA
g4 I 5 + NH4A g4 r 55CdS,
These include ZnS and Zn5e.

As the diffusible metal layer, Ag or Cu, Ag and Cu, or alloys containing Ag and/or Cu give particularly effective results.

Examples of alloys include: Cu40Ag
6oe CuloAgg□ e CuCu20A□ m
Cu 30Ag 70# Cu50Ag 56p
CuaoAg 40s C117C1176A u
B□Ag 20t Cu g□Ag 1 g e Ag
37G a631 A g5Hgg5mAg3oln
7os AgotL1o*Ag'yPb93*Ag2+
-+Te7o, e p Agt, 5T4s, s e
Cu13Ga87.

Cu2Hggg t Cu51 n95 # Cu7
Sng3 s Cu16Te 84 yG C5Sng
5 # Mg2,2P bg74 etc.

The diffusive metal layer needs to be selected to have a suitable thickness in relation to the intensity of the irradiated light, but it generally needs to be extremely thin;
In the case of a thickness of 0 mμ or more, it is impractical to completely interdiffuse and cause the entire diffusive metal layer to disappear due to the diffusion effect, that is, to change it into a different substance, as it requires long-term irradiation with strong light. Requires means.

Furthermore, if the thickness is extremely thin, such as 10 mμ or less, the uniformity of the diffusive metal film will become slightly porous, which is not desirable.

The range of 15 to 100 mμ is suitable in all respects, especially when it is not expected to completely eliminate the diffusive metal layer, i.e., when only the diffusive metal layer in the relatively exposed area is subsequently removed. The diffusive metal layer is 500 mμ
It may be more than that.

Implementation of the invention is illustrated in FIG. 2-$6.

The photosensitive member is exposed in a pattern without being exposed.

Pattern exposure is performed by any means such as optical image exposure or scanning of a light beam.

What is shown in FIG. 2 is pattern exposure through an original pattern.

Pattern exposure 1 is performed through an original pattern 4 having dark areas 5 and bright areas 6.

In the exposed portion of the photosensitive member, a diffusing portion 8 is formed by receiving the light energy.

For pattern exposure, strong radiation such as ultraviolet rays, visible light, infrared rays, and electron beams is used.

These radiations are collectively referred to as light in the present invention.

After patterning/exposure, treatment is performed with an acidic solution to dissolve and remove the diffusible metal layer remaining in the unexposed areas that did not contribute to diffusion, thereby forming the pattern member shown in FIG. 3.

Acidic solutions include various mineral acids and chromic acid mixtures (K2C
u207-H2SO4), aqua regia, ammonium nitrate, etc. are used.

In addition to being used as various pattern members in the state shown in Figure 3,
If necessary, by further treating with an alkali, the unexposed portions of the chalcogen/glass layer are dissolved and removed, resulting in a pattern member having the shape shown in FIG. 4, which can be used as various pattern members.

Typical examples of the alkali include aqueous or alcoholic solutions of alkali hydroxides such as Li, Na, and K, and alkaline solutions such as aqueous solutions of alkaline earth metal hydroxides such as Ba.

The remaining diffusible metal film and chalcogen glass layer are removed by utilizing the fact that the diffusion portion is insoluble or poorly soluble in alkalis and acids.

The examples shown in FIGS. 2 to 4 are the most ideal modes for forming the pattern member, but if the residual diffusible metal layer is not completely removed, the examples shown in FIGS. As shown in FIG. 2, the diffusible metal layer 1 that was not removed remains.

FIG. 5 shows a case in which a thin layer remains, and FIG. 6 shows a case in which a thin layer remains.

Note that FIGS. 5 and 6 show the case where an unremoved diffusive metal layer remains on the exposed area (diffusion area), but this is due to the intensity of light irradiation during pattern exposure. On the other hand, the thickness of the diffusive metal layer is relatively thick, and even in the exposed area,
A diffusive metal layer remains in a form that cannot fully contribute to diffusion (the amount of metal diffusion is approximately proportional to the amount of light irradiation), and the diffusive metal layer that remains in this exposed area can also be removed by treatment with an acidic solution. This probably indicates a case where it could not be completely removed.
If all of the diffusive metal layer contributes to diffusion and disappears in the exposed area, no diffusive metal layer remains on the exposed area (diffusion area) in FIGS. 5 and 6. However, the present invention will be explained with reference to FIGS. 5 and 6, including such a case. The unremoved diffusive metal layer as shown in FIGS. The material is then diffused into the diffusion section and disappeared, and is substantially transformed into the state shown in FIG. 3, thereby achieving the formation of an ideal pattern member.

The diffusive metal layer after pattern exposure is diffused into the chalcogen glass.In the exposed areas, due to sufficient exposure, the diffusive metal layer is diffused into the chalcogen glass, resulting in a significant loss of metal photosensitivity compared to the unexposed areas. However, in that case, if you magnify the exposed area with a microscope, it is observed that fine metal particles (appearing as small spots or white reflective surfaces) remain on the chalcogen glass surface overnight. Ru.

Further, if the residual diffusible metal layer in the exposed area and the residual diffusible metal layer in the unexposed area are dissolved away with acid and then similarly observed under a microscope, it is possible to recognize the residual form of metal fine particles on the surface.

In this case, the residual diffusible metal layer can be disappeared by increasing the acid etching time.
Prolonging the dissolution time promotes deterioration of the chalcogen glass part,
This is inconvenient because defects such as film peeling and contamination occur.

Therefore, a completely fixed pattern can be formed by diffusing the diffusible metal layer into the chalcogen glass again by exposing the entire surface to light after etching as shown in the method of the present invention.

Depending on the thickness of the residual diffusive metal layer, re-diffusion due to full-surface exposure may have the same effect as pattern exposure, increasing the optical density of the unexposed area (chalcogen glass layer) and conversely causing contamination. However, in reality, contamination does not occur, probably because the mechanism of metal diffusion is different between pattern exposure and full-surface exposure.

According to microscopic observation, it appears as if it is being sucked into the diffusion part.
Because diffusion is performed by full-surface exposure, there is a
It is possible to observe a phenomenon in which unremoved diffusible metal particles existing in the vicinity are preferentially diffused.

After the entire surface is exposed, no small spots or white reflective surfaces made of residual diffusive metal particles are observed, and a pattern member having a completely smooth surface is formed.

When used as a mask for high-precision reproduced pattern formation, the surface of the pattern member A = "F smoothness improves the wearability of the mask and maintains high resolution.

In addition, the patterned member is free from defects, and has particularly improved performance in terms of pattern contrast and resolution.

Examples will be described below.

Example 1 On a glass substrate, Ge52 was evaporated to a thickness of 500 mμ as a chalcogen glass, and Ag was evaporated to a thickness of 50 mμ as a metal layer.
, were deposited and laminated to form a photosensitive member.

The member was subjected to pattern exposure. Exposure was performed using a xenon lamp (250 W output), and the exposure time was 5 minutes.

Next, Ag was removed by etching and dissolution.

A 0.5N aqueous solution of ferric nitrate was used as the enching solution, and the samples were immersed for about 1 second.

At this stage, when the pattern surface after pattern exposure is observed using a microscope, if the dissolution and removal of Ag is insufficient, a white reflective area due to the residual Ag layer can be seen in the exposed area.

In this example, the entire surface was further exposed to light in order to remove the residual Ag layer.

The entire surface was exposed using the same light as the pattern exposure, and the exposure time was 1 minute.

When observed again under a microscope, no white reflective portion was visible on the surface of the pattern member, and a clear, high-contrast image was observed.

The contrast was increased by an optical density difference of 0.2 to 0.64 by the whole surface exposure compared to the case where the whole surface was not exposed.

Furthermore, the minimum line width was improved from 1.56μ to 10μ in terms of resolution.

Example 2 A laminated member of chalcogen glass As253 (film thickness: 600 mμ) and metal layer Ag (film thickness: 40 mμ) was subjected to pattern exposure, and then the entire surface was exposed using a 350 W ultra-high pressure mercury lamp.

Exposure time was 1 minute.

In the case of this example, since the etching of the Ag layer was relatively sufficient, the surface state had the structure shown in FIG.
) was diffused and completely disappeared.

, 1#M example, the pattern contrast is not improved much.

The optical density difference is about 0802 to 0.2.

There is no particular improvement in resolution either. However, since the diffusion of Ag was complete, the surface condition was stable, and there was no change over time, and the storage stability of the formed pattern and plane smoothness were improved.

Actual 113 As20Sy□Sel□kM metal layer of Cu'd 50 mμ thick was vapor-deposited on a polyethylene terephthalate substrate as chalcogen glass.

In this example, full-surface exposure was performed using either a xenon lamp or an ultra-high pressure mercury lamp.

In both cases, the exposure time was about 10 seconds, and the same results as in Examples 1 and 2 were obtained.

Example 4 On a polyethylene/terephthalate film substrate, As2S3Te□,2 was evaporated to a thickness of 30 mm as chalcogen/glass.
0 mμ, Ag was deposited as a metal layer to a thickness of 70 mμ to form a laminated photosensitive member.

Next, as an original pattern, 1. C. Using the pattern, the necessary conductive parts were exposed to light.

Exposure was performed using a 300W xenon lamp for an exposure time of 3 minutes.

Thereafter, the residual metal layer and the unexposed metal layer were dissolved and removed using a 1N aqueous solution of ferric nitrate.

The melting time was 30 seconds, and upon inspection, it appeared that the Ag on the surface had been completely removed.

Further, the entire surface of the etching pattern/member was exposed to light.

Exposure was performed for 1 minute using the same xenon lamp.

As a result, the electrical resistance of the Ag diffused portion of the IC pattern showed a decrease in resistance value of approximately one order of magnitude or more compared to that before the entire surface was exposed, and the cause of short circuits in the conductive portion made of the Ag diffused portion could be largely eliminated.

Therefore, stable nine conductive parts and defect-free conductive parts could be obtained.

[Brief explanation of the drawing]

FIG. 1 shows a typical photosensitive member used in the present invention. FIG. 2 shows the pattern exposure step. 3, 5 and 6 illustrate the step of removing the diffusible metal layer. FIG. 4 shows the chalcogen glass layer removal step. 1... Diffusion metal layer, 2... Chalcogen gas glass layer,
3... Support body, 8... Diffusion part.

Claims (1)

[Claims] 1 A photosensitive member having a stack of a chalcogen glass layer and a diffusible metal layer having a metal that diffuses into the chalcogen glass layer when exposed to light in a structure in which the chalcogen glass layer is in contact with the chalcogen glass layer is subjected to a pattern exposure process to prevent diffusion. 1. A method for forming a pattern member, which comprises performing a full-surface exposure process after dissolving and removing a residual diffusible metal layer that did not contribute.