CN108089396A - A kind of single slit diffraction mask plate and production method, thin film transistor (TFT), array substrate - Google Patents

Abstract

The present invention provides a single-slit diffraction mask and its manufacturing method, a thin film transistor, and an array substrate to obtain better resolution of conductive channel patterns. The single-slit diffraction mask provided by the present invention includes: A substrate, a light-shielding layer including slits arranged on the substrate, the material of the light-shielding layer is a phase-shifting material.

Description

A single-slit diffraction mask and manufacturing method, thin film transistor, and array substrate

technical field

The invention relates to the field of display technology, in particular to a single-slit diffraction mask, a manufacturing method, a thin film transistor, and an array substrate.

Background technique

A thin film transistor (Thin-film transistor, TFT) is a kind of field effect transistor, which is widely used in the field of display and plays a very important role in the working performance of the display device. A thin film transistor includes: a gate, a gate insulating layer, an active layer, a source and a drain. In the prior art, the active layer, the source electrode and the drain electrode in the thin film transistor can be made by using the same mask (mask), or the active layer can be made by using one mask, and the source and drain electrodes can be made by using another mask; wherein , using the same mask to make the active layer, source and drain masks is usually a single slit diffraction mask (Single Slit Mask, SSM), a gray tone mask (Gray Tone Mask, GTM) or a half tone mask (Half Tone Mask, HTM).

Usually, SSM uses chromium (Cr) material on the substrate to make a light-shielding layer (ie, a mask pattern) containing slits. After using the SSM to expose the photoresist, the slope angle of the photoresist in the part of the exposed area is generally 40 °, therefore, the TFT made of this SSM can obtain a better resolution of the conductive channel pattern, but with the development of technology, people hope to reduce the size of the TFT, thereby improving the resolution of the display, so it is necessary to use SSM to make The TFT can obtain better conductive channel pattern resolution.

Based on this, how to obtain better resolution of conductive channel patterns is a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

Embodiments of the present invention provide a single-slit diffraction mask, a manufacturing method, a thin film transistor, and an array substrate, so as to obtain better pattern resolution of conductive channels.

A single-slit diffraction mask provided by an embodiment of the present invention includes: a substrate, and a light-shielding layer including slits disposed on the substrate, and a material of the light-shielding layer is a phase-shifting material.

In the single-slit diffraction mask provided by the embodiment of the present invention, since the light-shielding layer is made of a phase-shifting material, after using the SSM to expose the photoresist, the slope angle of the photoresist in part of the exposed area is greater than 50°, corresponding to Compared with the prior art, the formed slope angle is larger, therefore, the TFT manufactured by using the SSM can obtain better conductive channel pattern resolution.

Preferably, the phase-shifting material is one or a combination of molybdenum-silicon compound and oxide.

Preferably, the light-shielding layer can change the phase of the transmitted exposure light by 180°.

Since the light-shielding layer can change the phase of the transmitted exposure light by 180°, the phase of the exposure light passing through the light-shielding layer and the exposure light passing through the slit can be reversed, so that the light-shielding layer and the adjacent area of the slit Subtractive interference makes the slope angle of the photoresist in the partially exposed area as large as possible, so as to obtain the best possible resolution of the conductive channel pattern.

Preferably, it further includes: a protective film disposed on the light-shielding layer; the protective film is disposed opposite to the light-shielding layer.

By arranging a protective film opposite to the light-shielding layer on the light-shielding layer, the light-shielding layer can be protected in this way.

Preferably, it further includes: a support provided at the edge region of the substrate; and the protective film is installed on the support.

Preferably, the protective film is provided separately from the light-shielding layer.

Preferably, the bracket is an adhesive tape.

The embodiment of the present invention also provides a thin film transistor, comprising: a gate, a gate insulating layer, an active layer, a source and a drain, and the active layer, the source and the drain of the thin film transistor adopt the same The single-slit diffraction mask plate provided by any embodiment of the invention is manufactured.

In the thin film transistor provided by the embodiment of the present invention, the active layer, the source electrode and the drain electrode of the thin film transistor are made of the same single-slit diffraction mask, and the light-shielding layer of the above-mentioned single-slit diffraction mask is made of a phase-shifting material. In this way, after using the SSM to expose the photoresist, the slope angle of the photoresist in the part of the exposed area is greater than 50°, compared with the prior art, the formed slope angle is larger, therefore, the TFT made by using the SSM can be Get better conductive channel pattern resolution.

An embodiment of the present invention also provides an array substrate, including the thin film transistor provided in any embodiment of the present invention.

The array substrate provided by the embodiment of the present invention adopts the above-mentioned thin-film transistor, and the above-mentioned thin-film transistor uses the same single-slit diffraction mask to make the active layer, source and drain of the thin-film transistor, and the above-mentioned single-slit diffraction The light-shielding layer of the mask plate is made of a phase-shifting material, so that after using the SSM to expose the photoresist, the slope angle of the photoresist in the part of the exposed area is greater than 50°. Compared with the prior art, the slope angle formed is smaller Therefore, the TFT made by using the SSM can obtain better conductive channel pattern resolution.

An embodiment of the present invention also provides a method for manufacturing a single-slit diffraction mask, the method comprising: using a phase-shifting material to form a light-shielding layer including a slit on a substrate.

The single-slit diffraction mask made by this method is made of a phase-shifting material because the light-shielding layer is made of a phase-shifting material, so after using the SSM to expose the photoresist, the slope angle of the photoresist in part of the exposed area is greater than 50°, compared to In the prior art, the formed slope angle is larger, therefore, the TFT fabricated by using the SSM can obtain better conductive channel pattern resolution.

Preferably, the light-shielding layer is formed on the substrate by using one or a combination of molybdenum-silicon compound and oxide.

Preferably, the method further includes: forming a protective film opposite to the light-shielding layer on the light-shielding layer.

Preferably, the method further includes: setting a support at the edge region of the substrate;

The forming of the protective film opposite to the light-shielding layer on the light-shielding layer specifically includes:

A protective film opposite to the light-shielding layer is installed on the bracket.

Description of drawings

FIG. 1 is a schematic structural diagram of a single-slit diffraction mask provided by an embodiment of the present invention;

Fig. 2 is a schematic structural diagram of another single-slit diffraction mask provided by an embodiment of the present invention;

3 is a schematic diagram of light amplitude and light intensity distribution after the exposure light passes through the SSM in the prior art;

4 is a schematic diagram of a photoresist pattern formed after exposure by SSM in the prior art;

Fig. 5 is a schematic diagram of light amplitude and light intensity distribution after the exposure light passes through the SSM provided by the embodiment of the present invention;

FIG. 6 is a schematic diagram of a photoresist pattern formed after exposure using the SSM provided by the embodiment of the present invention.

Detailed ways

Embodiments of the present invention provide a single-slit diffraction mask, a manufacturing method, a thin film transistor, and an array substrate, so as to obtain better pattern resolution of conductive channels.

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

It should be noted that the thickness and shape of each layer in the drawings of the present invention do not reflect the real scale, and the purpose is only to illustrate the contents of the present invention.

Referring to Fig. 1 and Fig. 2, a single-slit diffraction mask provided by an embodiment of the present invention includes: a substrate 11, a light-shielding layer 13 including a slit 12 disposed on the substrate 11, wherein the light-shielding layer 13 The material is a phase shift (Phase Shift, PS) material.

The above-mentioned single-slit diffraction mask plate is made of a phase-shifting material because the light-shielding layer 13 is made of a phase-shifting material, so after the photoresist is exposed by using the SSM, the slope angle of the photoresist in part of the exposed area is greater than 50°, compared with the prior art (The slope angle of the photoresist is generally about 40°), and the formed slope angle is larger. Therefore, the TFT manufactured by using the SSM can obtain better conductive channel pattern resolution.

The aforementioned substrate 11 may be, for example, a glass (Glass) substrate.

The width of the above-mentioned slit 12 is about 2.0-2.5 μm. What SSM utilizes is that when the width of the slit is smaller than the exposure precision, the photoresist is exposed using the SSM. Due to the relationship of single-slit diffraction, the light at the position opposite to the slit The resist cannot be completely removed, so that a photoresist step can be formed, and then the etching of the two-layer pattern can be completed by using the formed photoresist step.

In a preferred embodiment, the phase-shifting material may be one or a combination of molybdenum-silicon compound and oxide (such as SiO ₂ ). In addition, the phase-shifting material can also be an organic phase-shifting material.

In a preferred embodiment, as shown in FIG. 1 , the light-shielding layer 13 can change the phase of the transmitted exposure light by 180°. Since the light-shielding layer can change the phase of the transmitted exposure light by 180°, the phase of the exposure light passing through the light-shielding layer and the exposure light passing through the slit can be reversed, so that the light-shielding layer and the adjacent area of the slit Subtractive interference makes the slope angle of the photoresist in the partially exposed area as large as possible, so as to obtain the best possible resolution of the conductive channel pattern.

In a preferred embodiment, as shown in Figure 2, in order to protect the light-shielding layer, the single-slit diffraction mask can also include: a protective film 14 arranged on the light-shielding layer 13; wherein, the protective film 14 is opposite to the light-shielding layer 13 set up.

In a preferred embodiment, as shown in FIG. 2 , the single-slit diffraction mask may further include: a support 15 disposed at the edge of the substrate 11 ; and the protective film 14 is mounted on the support 15 . Wherein, the bracket 15 can be, for example, an adhesive tape. Since the protective film 14 is installed on the bracket 15, it is convenient for subsequent maintenance.

In a preferred embodiment, as shown in FIG. 2 , the protective film 14 and the light-shielding layer 13 are disposed separately. Since the protective film 14 is disposed separately from the light-shielding layer 13 , the influence of thermal expansion and contraction on the SSM can be reduced. Certainly, the protective film 14 may also be disposed in contact with the upper surface of the light shielding layer 13 , which is not limited in this embodiment of the present invention.

It should be pointed out that the protective film 14 may also be directly disposed on the light shielding layer 13 , which is not limited in this embodiment of the present invention.

Based on the same inventive concept, an embodiment of the present invention also provides a method for manufacturing a single-slit diffraction mask, the method comprising: using a phase-shifting material to form a light-shielding layer including a slit on a substrate.

Specifically, a phase-shifting material may be deposited on the substrate, and then a preset mask pattern is formed through a patterning process, that is, a light-shielding layer including slits is formed.

In a preferred embodiment, the light-shielding layer is formed on the substrate by using one or a combination of molybdenum-silicon compound and oxide.

In a preferred embodiment, the formed light-shielding layer can change the phase of the transmitted exposure light by 180°.

In a preferred embodiment, the method may further include: forming a protective film opposite to the light-shielding layer on the light-shielding layer.

In a preferred embodiment, the method may further include: arranging a bracket at the edge region of the substrate; for example, adhering adhesive tape around the edge region of the substrate;

The above-mentioned formation of a protective film opposite to the light-shielding layer on the light-shielding layer specifically includes:

A protective film opposite to the light-shielding layer is installed on the bracket.

Wherein, the protective film and the light-shielding layer can be arranged separately.

Based on the same inventive concept, an embodiment of the present invention also provides a thin film transistor, including: a gate, a gate insulating layer, an active layer, a source and a drain, and the active layer, the source and the drain of the thin film transistor The pole is made by using the same single-slit diffraction mask provided by any embodiment of the present invention.

The manufacturing method of the thin film transistor provided by the embodiment of the present invention is similar to the manufacturing method of the thin film transistor in the prior art, and the same parts will not be repeated here, and only the different parts will be described below.

In the prior art, the active layer, the source and the drain of the thin film transistor are made of the same SSM (the material of the light-shielding layer 01 is Cr material). After the exposure light passes through the SSM, its light amplitude and light intensity are shown in Figure 3. After using the SSM to expose the photoresist, the photoresist steps formed are shown in Figure 4, and the slope angle _θ1 of the photoresist in the part of the exposed area is generally about 40°.

In the thin film transistor provided by the embodiment of the present invention, the active layer, the source electrode and the drain electrode are made of the same SSM (the material of the light-shielding layer 13 is a phase shift (PS) material), wherein the light transmittance of the PS material is lower than 5%. After the exposure light passes through the SSM, its light amplitude and light intensity are shown in Figure 5. After using the SSM to expose the photoresist, the photoresist steps formed are shown in Figure 6, and the slope angle of the photoresist in the part of the exposed area is _θ2 is greater than 50°.

It can be seen from Figure 5 that the phase of the light passing through the PS material is opposite to that of the light passing through the slit, and the generated light amplitude passes through the zero point, resulting in destructive interference, and the light intensity is weakened in the adjacent area, which improves the contrast of the light intensity distribution , that is, the intensity of the light passing through the slit converges toward the center, and the slope of the light intensity at adjacent points increases, so the resolution capability is improved. It can be seen from FIG. 4 and FIG. 6 that the SSM provided by the embodiment of the present invention can obtain better graphic resolution than the common SSM.

Based on the same inventive concept, an embodiment of the present invention further provides an array substrate, including the thin film transistor provided in any embodiment of the present invention. The array substrate can be used for a liquid crystal display (Liquid Crystal Display, LCD) or an organic electroluminescent display (Organic Electroluminescent Display, OLED).

To sum up, in the technical solution provided by the embodiment of the present invention, since the light-shielding layer of the single-slit diffraction mask is made of a phase-shifting material, after using the SSM to expose the photoresist, the photolithography of part of the exposed area The slope angle of the glue is greater than 50°, and the formed slope angle is larger than that of the prior art. Therefore, the TFT manufactured by using the SSM can obtain better conductive channel pattern resolution.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (13)

1. A single-slit diffraction mask, comprising: a substrate, and a light-shielding layer including slits arranged on the substrate, characterized in that the material of the light-shielding layer is a phase-shifting material. 2. The single-slit diffraction mask according to claim 1, wherein the phase-shifting material is one of molybdenum-silicon compound, oxide or a combination thereof. 3 . The single-slit diffraction mask according to claim 1 , wherein the light-shielding layer can change the phase of the transmitted exposure light by 180°. 4 . 4. The single-slit diffraction mask according to any one of claims 1-3, further comprising: a protective film disposed on the light-shielding layer; the protective film is disposed opposite to the light-shielding layer . 5 . The single-slit diffraction mask according to claim 4 , further comprising: a bracket disposed at the edge region of the substrate; and the protective film is mounted on the bracket. 6 . The single-slit diffraction mask according to claim 5 , wherein the protective film is separated from the light-shielding layer. 7. The single-slit diffraction mask according to claim 5, wherein the bracket is an adhesive tape. 8. A thin film transistor, comprising: gate, gate insulating layer, active layer, source and drain, characterized in that the active layer, source and drain of the thin film transistor adopt the same Manufactured from the single-slit diffraction mask described in any one of requirements 1-7. 9. An array substrate comprising the thin film transistor according to claim 8. 10. A method for manufacturing a single-slit diffraction mask, characterized in that the method comprises: using a phase-shifting material to form a light-shielding layer including slits on a substrate. 11 . The method according to claim 10 , wherein the light-shielding layer is formed on the substrate by using one or a combination of molybdenum-silicon compound and oxide. 12 . The method according to claim 10 or 11 , further comprising: forming a protective film opposite to the light-shielding layer on the light-shielding layer. 13 . 13. The method according to claim 12, further comprising: arranging a support in the edge region of the substrate; The forming of the protective film opposite to the light-shielding layer on the light-shielding layer specifically includes: A protective film opposite to the light-shielding layer is installed on the bracket.