阅读说明：本技术 薄膜结构 (Thin film structure ) 是由 谢文俊 林振吉 于 2018-06-27 设计创作，主要内容包括：本发明提供一种薄膜结构,其包括非晶硅薄膜以及多个纳米粒子。多个纳米粒子于非晶硅薄膜的表面上,且多个纳米粒子的材料包括光热效应材料,因此可以提升非晶硅薄膜于融化再结晶的过程中的大面积结晶均匀性。(The invention provides a film structure, which comprises an amorphous silicon film and a plurality of nano particles. The nano particles are arranged on the surface of the amorphous silicon film, and the material of the nano particles comprises a photo-thermal effect material, so that the large-area crystallization uniformity of the amorphous silicon film in the melting and recrystallization process can be improved.)

1. A film structure, comprising:

an amorphous silicon thin film; and

the nano particles are arranged on the surface of the amorphous silicon thin film, and the material of the nano particles comprises a photothermal effect material.

2. The thin film structure of claim 1, wherein the plurality of nanoparticles are rod-shaped nanoparticles, and the extending direction of the rod-shaped nanoparticles is not perpendicular to the surface of the amorphous silicon thin film.

3. The film structure of claim 2, wherein each of the plurality of rod-shaped nanoparticles comprises a core layer and a dielectric skin layer, the dielectric skin layer surrounds the core layer, and a material of the core layer is different from a material of the dielectric skin layer.

4. The film structure of claim 3, wherein the material of the core layer comprises a metal, and the material of the dielectric skin layer is selected from one or more of silicon oxide, silicon nitride, and silicon oxynitride.

5. The film structure of claim 3, wherein the dielectric skin layer is formed by coating.

6. The film structure of claim 3,

the thickness of the dielectric skin layer is between 5 nanometers and 50 nanometers; or

The proportion of the sum of the sectional areas of the plurality of rod-shaped nano particles to the surface area of the amorphous silicon film is between 30% and 100%.

7. The thin film structure of claim 2, wherein the material of the plurality of rod-shaped nanoparticles comprises silicon or germanium.

8. The film structure according to any one of claims 2 to 7,

the aspect ratio of the plurality of rod-shaped nanoparticles is between 1.1 and 10; or

The coating density of the rod-shaped nano particles on the amorphous silicon film is more than 1.5 multiplied by 10¹³Per square centimeter.

9. The thin film structure of claim 1, wherein the plurality of nanoparticles are made of one or more materials selected from the group consisting of silicon, metal-doped silicon, germanium-based semiconductors of the third five groups, metal sulfides of copper sulfide, carbon nanotubes, carbon-based materials of graphene, magnetic materials of iron oxide, quantum dots, and up-conversion materials.

10. The film structure of claim 9,

the particle size of the plurality of nanoparticles is between 10 nanometers and 100 nanometers; or

The coating density of the plurality of nano particles on the amorphous silicon film is between 5 per square micron and 100 per square micron.

Technical Field

The present invention relates to a thin film structure, and more particularly, to a thin film structure including nanoparticles.

Background

In the existing processes, the preparation method of the polysilicon (c-Si) film includes Low Pressure Chemical Vapor Deposition (LPCVD), Plasma Enhanced Chemical Vapor Deposition (PECVD), Solid Phase Crystallization (SPC), excimer laser crystallization (ELA), Rapid Thermal Annealing (RTA), and metal lateral induction (MILC), wherein the excimer laser method can be performed at a low temperature, and the prepared polysilicon film has large crystal grain, good spatial selectivity, high doping efficiency, few in-crystal defects, good electrical properties, and high electron mobility up to 400 cm/v sec, and is favored.

The excimer laser method heats and melts amorphous silicon by using laser pulses, and the amorphous silicon (a-Si) film is recrystallized to form a polysilicon film. However, excimer lasers are generally in the ultraviolet band, and the equipment is expensive and difficult to produce large-area illumination. In addition, the excimer laser method has a problem of poor crystallization uniformity with respect to a large-area amorphous silicon thin film.

Disclosure of Invention

The invention provides a film structure which can improve large-area crystallization uniformity of an amorphous silicon film in a melting and recrystallization process.

According to an embodiment of the present invention, the thin film structure includes an amorphous silicon thin film and a plurality of nanoparticles. The plurality of nano particles are arranged on the surface of the amorphous silicon thin film, and the material of the plurality of nano particles comprises a photothermal effect material.

Preferably, the plurality of nanoparticles are a plurality of rod-shaped nanoparticles, and the extending direction of the plurality of rod-shaped nanoparticles is not perpendicular to the surface of the amorphous silicon thin film.

Preferably, the plurality of rod-shaped nanoparticles comprise a core layer and a dielectric skin layer, the dielectric skin layer wraps the core layer, and the material of the core layer is different from that of the dielectric skin layer.

Preferably, the material of the core layer comprises a metal, and the material of the dielectric skin layer is selected from one or more of silicon oxide, silicon nitride and silicon oxynitride.

Preferably, the dielectric skin layer is formed via coating.

Preferably, the dielectric skin layer has a thickness between 5 nanometers and 50 nanometers.

Preferably, the proportion of the sum of the cross-sectional areas of the plurality of nanoparticles to the surface area of the amorphous silicon thin film is between 30% and 100%.

Preferably, the material of the plurality of rod-shaped nanoparticles comprises silicon or germanium.

Preferably, the aspect ratio of the plurality of rod-shaped nanoparticles is between 1.1 and 10.

Preferably, the coating density of the plurality of rod-shaped nanoparticles on the amorphous silicon thin film is more than 1.5 x 10¹³Per square centimeter.

Preferably, the material of the plurality of nanoparticles is selected from one or more of silicon, metal-doped silicon, a germanium-based semiconductor of the third five groups, a copper sulfide-based metal sulfide, a carbon nanotube, a graphene-based carbon-based material, an iron oxide-based magnetic material, a quantum dot and an up-conversion material.

Preferably, the plurality of nanoparticles has a particle size material between 10 nanometers and 100 nanometers.

Preferably, the coating density of the plurality of nanoparticles on the amorphous silicon thin film is between 5/sq micrometer and 100/sq micrometer.

In the thin film structure according to the embodiment of the invention, the surface of the amorphous silicon thin film is provided with the plurality of nano particles, and the material of the plurality of nano particles comprises the photothermal effect material, so that the plurality of nano particles can be irradiated by light, and the large-area crystallization uniformity of the amorphous silicon thin film in the melting and recrystallization process can be further improved.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

FIG. 1 is a schematic cross-sectional view of a thin-film structure according to a first embodiment of the present invention;

fig. 2 is a schematic cross-sectional view of a thin-film structure according to a second embodiment of the present invention.

Description of reference numerals:

100. 200: a thin film structure;

110: an amorphous silicon thin film;

110 a: a surface;

120. 220, and (2) a step of: nanoparticles;

120 a: a core layer;

120 b: a dielectric skin layer;

130: a light;

l1: thickness;

t1, t 2: length.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are disclosed so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art, and the present invention will only be defined by the appended claims. Like reference numerals designate like elements throughout the specification, and the sizes of some portions may be exaggerated for clarity of embodiments of the present invention.

Fig. 1 is a schematic cross-sectional view of a thin-film structure according to a first embodiment of the present invention.

Referring to fig. 1, a thin film structure 100 of the first embodiment includes an amorphous silicon thin film 110 and a plurality of nanoparticles 120. The plurality of nanoparticles 120 are disposed on the surface 110a of the amorphous silicon thin film 110, and the material of the plurality of nanoparticles 120 includes a photothermal (photothermal) effect material.

In some embodiments, the material of the nanoparticles 120 may be one or more selected from silicon, metal-doped silicon, germanium-based semiconductors of the iii-v group, metal sulfides of copper sulfide, carbon nanotubes, carbon-based materials of graphene, magnetic materials of iron oxide type, Quantum Dots (QD), and up-conversion (up-conversion) materials, but the invention is not limited thereto. The single nanoparticle 120 may be one or more of the materials described above. Alternatively, the material of each nanoparticle 120 of the plurality of nanoparticles 120 may be the same as or different from each other, which is not limited in the present invention.

In some embodiments, the particle size of the nanoparticles 120 may be between 10 nanometers (nm) to 100 nm. On the nano scale (nanoscale), the nano particles 120 may exhibit different physical or chemical properties from bulk (bulk) of the same material.

In some embodiments, the aspect ratio of the nanoparticles 120 is between 0.5 and 10. That is, the nanoparticles 120 may be rod-shaped or granular.

The plurality of nanoparticles 120 of the present invention comprise a photothermal effect material. If a light source (not shown) is provided, the light 130 emitted from the light source irradiates the plurality of nanoparticles 120, and the plurality of nanoparticles 120 absorb the light energy and then convert the light energy into heat energy, and the heat energy is used as the phase change energy required when the amorphous silicon thin film is converted into the polysilicon thin film. By the above method, the converted heat energy can be transferred on the amorphous silicon thin film 110 more uniformly, and further, the uniformity of large-area crystallization can be improved in the process of melting and recrystallizing the amorphous silicon thin film. The light 130 emitted by the light source is, for example, infrared light with a wavelength between 700 nm and 1400 nm, and the light source may be a laser, a xenon lamp, a mercury lamp, a halogen lamp, or an array light emitting diode. In some embodiments, the array light emitting diodes are used as the light source to further reduce the cost of the manufacturing equipment, but the invention is not limited thereto.

Referring to fig. 1, in the embodiment, the nanoparticles 120 are rod-shaped, but the invention is not limited thereto. In other embodiments, the nanoparticles may be granular, spherical, or ellipsoidal in shape. The extending direction of the rod-shaped nanoparticles 120 (i.e., the long axis direction of the rod shape) is not perpendicular to the surface 110a of the amorphous silicon thin film 110. When the extending direction of the rod-shaped nanoparticles 120 is not perpendicular to the surface 110a of the amorphous silicon thin film 110, the rod-shaped nanoparticles 120 may have more irradiated areas, and thus may have better photo-thermal conversion efficiency, and may further improve the light utilization rate of the light 130 emitted by the light source.

In the present embodiment, the extending direction of the rod-shaped nanoparticles 120 is parallel to the surface 110a of the amorphous silicon thin film 110. Of course, if some of the rod-shaped nanoparticles 120 are irregularly stacked on the surface 110a of the amorphous silicon thin film 110, the extending direction of the rod-shaped nanoparticles 120 irregularly stacked may be slightly non-parallel to the surface 110a of the amorphous silicon thin film 110. In addition, the surface 110a of the amorphous silicon thin film 110 formed by the deposition method may have partial recesses or protrusions, and if some of the rod-shaped nanoparticles 120 happen to be located on the recesses or protrusions of the surface 110a of the amorphous silicon thin film 110, the extending directions of the rod-shaped nanoparticles 120 located on the recesses or protrusions of the surface 110a of the amorphous silicon thin film 110 may be slightly non-parallel to the surface 110a of the amorphous silicon thin film 110. The above-mentioned situation still falls within the equivalent range of "the extending direction of the plurality of rod-shaped nanoparticles 120 is parallel to the surface 110a of the amorphous silicon thin film 110" in the present disclosure.

In some embodiments, the plurality of rod-shaped nanoparticles 120 may have an aspect ratio of between 1.1 and 10, the aspect ratio being the ratio between the length t1 of core layer 120a and the diameter of core layer 120 a. The coating density of the rod-shaped nanoparticles 120 on the amorphous silicon thin film 110 is, for example, greater than 1.5 × 10¹³Per square centimeter.

In this embodiment, the rod-shaped nanoparticles 120 may include a core layer 120a and a dielectric skin layer 120b, the dielectric skin layer 120b completely covers the outer surface of the core layer 120a, and the melting point of the dielectric skin layer 120b is greater than the melting point of the nanoparticles 120. In other words, a part of the dielectric skin layer 120b is located between the core layer 120a and the amorphous silicon thin film 110, so that the core layer 120a is not in direct contact with the amorphous silicon thin film 110. The material of the core layer 120a may be metal, and the material of the dielectric skin layer 120b may be selected from silicide, which may be one or more of silicon oxide, silicon nitride, and silicon oxynitride. When the photothermal effect occurs, the ambient temperature around the nanoparticles 120 may be increased. If the material of the nanoparticles is only a material (e.g., gold) with a low melting point (i.e., lower than the conversion temperature for the amorphous silicon to form polysilicon after recrystallization), the nanoparticles may melt and combine into particles or blocks with a diameter larger than that of the nanoparticles 120, thereby reducing the photothermal effect and even causing the photothermal effect to fail. Therefore, the present invention completely wraps the core layer 120a by the dielectric skin layer 120b, which can reduce the risk that the core layers 120a are fused with each other due to the temperature rise, thereby allowing the photothermal effect to be continuously performed. In addition, it is further noted that at the nanoscale, various substances may exhibit physical or chemical properties different from those of bulk materials of the same material, such as: the melting point of gold lumps is about 1063 ℃, while the melting point of the gold nanoparticles, depending on their nanoscale, can be lowered to 300 ℃ to 700 ℃, again for example: the melting point of the silver block is about 962 ℃, and the melting point of the nano silver particles can be even reduced to 100 ℃ according to the nano scale of the nano silver particles. Therefore, in some embodiments, when the material of the core layer 120a is metal (such as gold or silver), the amorphous silicon thin film 110 is not contaminated by the metal layer 120a wrapped by the dielectric skin layer 120b, thereby reducing the number of process steps and increasing the production efficiency.

In some embodiments, the dielectric skin layer 120b may be formed through a coating process (coating process), and the dielectric skin layer 120b may be completely wrapped on the outer surface of the core layer 120 a. For example, when the material of the dielectric skin layer 120b is silicon oxide, Tetraethoxysilane (TEOS) is utilized to perform a hydrolytic condensation reaction, and then the hydrolytic condensation reaction and the material of the core layer 120a form a suspension, and the suspension is coated on the surface of the amorphous silicon thin film 110, but the invention is not limited thereto. In some embodiments, the thickness L1 of the dielectric skin layer 120b may be between 5 nanometers and 50 nanometers. If the thickness L1 of the dielectric skin layer 120b is less than 5 nm, the possibility of breakage or deformation of the dielectric skin layer 120b is increased. If the thickness L1 of the dielectric skin layer 120b is greater than 50 nm, thermal conduction may be reduced due to the photothermal effect. Preferably, when the thickness L1 of the dielectric skin layer 120b is greater than or equal to 20 nm and less than or equal to 50 nm, it is easier to manufacture the dielectric skin layer 120b (i.e., it has a better process window), and it is better to reduce the possibility of the dielectric skin layer 120b being damaged or deformed, thereby preventing the core layers 120a from being fused into each other or into nanoparticles due to the temperature rise, and the thermal conductivity is better in the photo-thermal effect. The ratio of the sum of the cross-sectional areas of the rod-shaped nanoparticles 120 to the surface area of the amorphous silicon thin film 110 may be between 30% and 100%, but the invention is not limited thereto.

Fig. 2 is a schematic cross-sectional view of a thin-film structure according to a second embodiment of the present invention.

Referring to fig. 2, a thin film structure 200 of the second embodiment is different from the thin film structure 100 of the first embodiment in that the material of the nanoparticles 220 is silicon or germanium. Specifically, the nanoparticles 220 have a single-layer structure. The melting temperature of the silicon or germanium nano material is far higher than the temperature generated in the photo-thermal effect, or is higher than the conversion temperature of polycrystalline silicon formed by amorphous silicon recrystallization. For example, the melting temperature of the silicon-based nanomaterial is 1327 ℃. Therefore, when the material of the nanoparticles 220 is silicon or germanium, the nanoparticles 220 can be more easily prevented from being deformed due to heat. In addition, in some embodiments, when the material of the nanoparticles 220 is a silicon-based nanomaterial, the silicon-based nanomaterial has a seed function for crystallization, and thus the crystallization time can be shortened and the productivity can be improved, but the invention is not limited thereto.

In some embodiments, the particle size of the plurality of nanoparticles 220 may be between 10 nanometers (nm) and 100 nm, and the aspect ratio of the nanoparticles 220 is between 1.1 and 10. That is, the nanoparticles 220 may be rod-shaped or granular. In addition, the aspect ratio is the ratio of the length t2 of the nanoparticle 220 to the diameter of the nanoparticle 220.

In the embodiment, the nanoparticles 220 are rod-shaped, and the coating density of the rod-shaped nanoparticles 220 on the amorphous silicon thin film 110 is, for example, greater than 1.5 × 10¹³Per square centimeter.

In other embodiments, if the material of the nanoparticles is silicon or germanium, the nanoparticles may be granular, and the coating density of the granular nanoparticles on the amorphous silicon thin film 110 is, for example, between 5/sq μm and 100/sq μm.

In summary of the disclosure, in the thin film structure of the present invention, the surface of the amorphous silicon thin film has a plurality of nanoparticles, and the material of the plurality of nanoparticles includes the photothermal effect material, so that the plurality of nanoparticles can be irradiated by light, and the large-area crystallization uniformity of the amorphous silicon thin film in the melting and recrystallization process can be further improved.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.