KR20110014258A - Methods for forming nano devices using nanostructures having self assembly characteristics - Google Patents

Abstract

PURPOSE: A formation method of a nano device is provided to perform an ion implantation process and an etching process in a nano scale while not applying an exposure process. CONSTITUTION: A formation method of a nano device comprises the steps of: forming a nanoscale self-assembly material layer(23) on a substrate(21) which has at least one layer; forming a mask layer(25) on the self-assembly material layer; performing a surface treatment process on the substrate; and removing the self-assembly material layer. The surface treatment process is an etching process or ion injection process.

Description

Method for forming nano devices using nanostructures having self assembly characteristics}

The present invention relates to a method for forming a nano device, and more particularly, to a method for forming a nano device that can produce a nano device using a nanostructure having self-assembly.

In general, as semiconductor devices become more compact and multifunctional, design rules of semiconductor devices are decreasing. However, there is a limit to miniaturization while improving the performance of the semiconductor element by the conventional method. Therefore, nanotechnology has been applied to semiconductor devices to reduce the size of semiconductor devices and to process fast response speeds, compact sizes, and large amounts of information. Such nano technology means a technology for synthesizing, assembling, controlling, measuring, or characterizing materials in small size units such as atoms or molecules requiring 1 billionth of a degree of precision.

An example of the technique which applied the above nanotechnology to manufacture of a semiconductor element is disclosed by following Document 1. The technique disclosed in [Document 1] provides a method of forming a nanoscale inclined structure used as a liquid crystal display and / or a nanoprinting template. In particular, the semiconductor wafer substrate of the invention disclosed in [Document 1] is prepared with at least one material layer. A photoresist is formed on the substrate to undergo exposure and development. An anisotropic ion etch process is performed in the direction of the structure that is inclined at a relatively large angle to the wafer to remove the unprotected material layer. The remaining photoresist cap blocks at least one material layer region, and as the ion etching process is performed, the protective region of the material layer appears inclined.

However, the technique disclosed in the following [Document 1] forms a pattern on the photoresist from the exposure process. Therefore, there may be a limit in reducing the minimum feature size of the semiconductor device due to the wavelength limit of the light source used in the exposure process. As a next-generation exposure technology to solve this problem, technologies using short wavelengths such as deep UV (ultraviolet), X-ray or E-beam, and patterning methods using polymer materials other than photoresist have been studied.

Thus, an example of the technique of patterning a nanometer standard using a light source is disclosed by [following document 2] and [following document 3]. The technique disclosed in [Document 2] and [Document 3] forms anodized aluminum oxide (AAO) by oxidizing aluminum, and using this as a mask, does not etch a pattern of a nanometer standard or use a light source. If not, the nanometer patterning method is applied by applying external energy such as electron beam.

In addition, in order to solve the above problems, techniques for forming nanostructures using materials having self-assembling properties such as DNA molecules have also been studied. An example of the technique using such a characteristic is disclosed in [document 4]-[document 6] below. [Document 4] to [Document 6] disclose a technique of manipulating DNA sequencing utilizing self-assembling properties and designing DNA nanostructures using the same.

On the other hand, in order to produce a nano-device using a DNA molecule, a technique for producing a nanowire or a nano-electrode is required, such a technique is disclosed in [document 7] and [document 8]. [Document 7] and [Document 8] relate to a study on the substitution of metal particles and ions based on DNA molecules. Accordingly, the nanometer-based DNA nanowires or nanoelectrodes having a nanometer spacing may be formed by substituting positive ions having different polarities with negative charges of the DNA molecular skeleton.

In addition to the following [9] to [11], there is disclosed a technique for manufacturing nanostructures in two and three dimensions in addition to the technique for producing nanowires, and in [document 12] having nanometer specifications. A research has been disclosed for depositing thin films and forming nanostructures using three-dimensional DNA nanostructures. In addition, the following Document 13 discloses a technique of fabricating a nanostructure by fabricating a structure of a desired shape by manipulating the nucleotide sequence of a DNA molecule having self-assembly properties, and depositing a thin film and then transferring it to a desired position on a substrate. have.

[Document 1] US Patent Publication No. 6897158 (registered May 24, 2005)

[Document 2] United States Patent Publication 6664123 (2003.12.16 registration)

[Document 3] United States Patent Publication 6709929 (registered on March 24, 2004)

[Document 4] United States Patent Publication 6255469 (registered on July 3, 2001)

[Patent 5] United States Patent Application Publication No. 2007/0117109 (published May 24, 2007)

[Document 6] United States Patent Application Publication 2005/0244865 (registered on November 3, 2005)

[Document 7] United States Patent Publication No. 6946675 (registered September 20, 2005)

8, Science, Kinneret Keren et al., “Sequence-Specific Molecular Lithography on Single DNA Molecules”, p. 72, 2002

9, Science, Hao Yan, Sung Ha Park, Gleb Finkelstein, John H. Rief, Thomas H. Labean "DNA-templated self-assembly of protein array and highly conductive nanowires", p. 1882, 2003

10, Nature, Willian M. Shin, Joel D. Quispe and Gerald F. Joyce, "A 1.7-kilobase single-stranded DNA that folds into a nanoscale octahedron", 619, 2004

[11] Nature, Paul W. K. Rothemund, "Folding DNA to create nanoscale shapes and patterns", p. 297, 2006

12, Small, Hecor A. Becerrile and Adam T. Woolley, "DNA shadow nanolithgoraphy" p. 1534, 2007

13 ngew. Chem., Z. Deng and C. Mao, "Molecular lithography with DNA nanostructures"

However, in the technique disclosed in Document 1, there is a problem that the exposure of the nanometer standard is difficult due to the wavelength limitation of the light source used in the prior art, so that there is a limitation in reducing the design rule of the device manufacturing process.

 In addition, in the techniques disclosed in Documents 2 and 3, there is a problem in that the manufacturing process of the device is complicated by patterning a mask using a light source or an electron beam, and the manufacturing cost of the device is high.

In addition, in the techniques disclosed in Documents 12 and 13, there is a problem that it is difficult to control the shape and position of the nanostructure, and the manufacturing process of the nano device is complicated.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems as described above, and to form a mask layer without using a light source, and even using a method for patterning a substrate using the method of forming a nano device that can control the precision of nanoscale To provide.

Another object of the present invention is to provide a method of forming a nano device capable of performing an ion implantation process or an etching process at a nanoscale without applying an exposure process on a substrate.

Still another object of the present invention is to provide a method for forming a nano device, which can reduce the manufacturing process of the device, lower the manufacturing cost, and improve the integration and manufacturing yield of the device.

In order to achieve the above object, a method of forming a nano device according to the present invention includes forming a nanoscale self-assembled material layer on a substrate of at least one layer, and forming a mask layer on the self-assembled material layer. And performing a surface treatment process on the substrate using the mask layer as a mask and removing the self-assembled material layer.

In addition, in the method of forming a nano device according to the present invention, the surface treatment process is characterized in that the etching process or ion implantation process.

In addition, in the method of forming a nano device according to the present invention, the mask layer may include gold (Au), silver (Ag), silicon (Si), silicon oxide (SiO ₂ ), silicon nitride (SiN), iron (Fe), Cadmium selenide (CdSe), carbon nanotubes (CNT), buckyball (buckyball) and is characterized in that it comprises any one material selected from griffin (Graphine).

In addition, in the method of forming a nano device according to the present invention, the self-assembling material layer is characterized in that it comprises any one material selected from DNA molecules, proteins, synthetic polymers and carbon-based materials.

In addition, in the method of forming a nano device according to the present invention, the carbon-based material is characterized in that it comprises any one material selected from carbon nanotubes (CNT), buckyballs and griffin (Graphine).

In addition, in the method of forming a nano device according to the present invention, each of the DNA molecule and the protein is removed by a heat treatment process or an acid solution, the synthetic polymer is removed using a heat treatment process or a chemical agent, and the carbon-based material Characterized in that it is removed with a chemical to selectively remove the carbon-based material.

In addition, the method of forming a nano device according to the present invention comprises the steps of forming an insulating film on a substrate having an active region, forming a conductive film on the insulating film, forming a layer of a self-assembly material on the conductive film, the Patterning the conductive layer and the insulating layer in sequence using a self-assembled material layer as an etch mask to form a conductive layer pattern and an insulating layer pattern, and forming an ion implantation region in the substrate using the self-assembled material layer as an ion implantation mask. It is characterized by including.

The method of forming a nano device according to the present invention may further include removing the self-assembled material layer after forming the ion implantation region and forming a spacer layer on sidewalls of the conductive layer pattern and the insulating layer pattern. It is characterized by.

As described above, according to the method for forming a nano device according to the present invention, by using the nanostructure having self-assembly properties, the effect of patterning the substrate on a nanoscale without using a light source is obtained.

In addition, according to the method of forming a nano device according to the present invention, by forming a mask layer using a nanostructure on a substrate, the effect that the ion implantation process and the etching process can be performed at a nanoscale without applying an exposure process is obtained. .

In addition, according to the method for forming a nano device according to the present invention, the effect of reducing the manufacturing cost of the device can be reduced, and the degree of integration of the device can be improved.

In addition, according to the method for forming a nano device according to the present invention, by producing a nano device using a nanostructure having a self-assembly properties can be obtained the effect of improving the yield of the device manufacturing.

1 is a view showing a method of forming a nanostructure using complementary binding properties between the base of the DNA molecule according to an embodiment of the present invention.
2A to 2C are AFM images of DNA nanostructures formed by the method of FIG. 1.
3a to 3d are views showing an etching process using a nanostructure according to an embodiment of the present invention.
4 is an AFM photograph of a nanowire formed on a DNA nanostructure according to one embodiment of the present invention.
5a to 5c are views illustrating an ion implantation process using a nanostructure according to another embodiment of the present invention.
6a to 6e are views showing a method of forming a transistor using a nanostructure according to another embodiment of the present invention.

The above and other objects and novel features of the present invention will become more apparent from the description of the specification and the accompanying drawings.

EMBODIMENT OF THE INVENTION Hereinafter, the structure of this invention is demonstrated in detail according to drawing. Prior to this, a method of forming a nanostructure that can be combined with a mask layer using DNA molecules having self-assembly as an example will be described.

1 is a view showing a method of forming a nanostructure using the complementary binding properties between the base of the DNA molecule according to an embodiment of the present invention, Figure 2a to 2c is a DNA nanostructure formed by the method of Figure 1 AFM pictures of

As shown in FIG. 1, nanometer-sized deoxyribonucleoic acid (DNA) molecules have four different bases. The bases are composed of adenine (A), thymine (T) guanine (G), and cytosine (C). In this case, as indicated by reference numeral 11, adenine (A) and thymine (T) are bonded by hydrogen double bonds, and as indicated by reference numeral 13, guanine (G) and cytosine (C) by hydrogen triple bonds To combine. Thus, DNA molecules are replicated by the complementary binding of adenine (A) and thymine (T) and guanine (G) and cytosine (C). As a result, by attaching the DNA strand manipulated the nucleotide sequence using the characteristics of such DNA molecules, the DNA molecules can be replicated in the direction of the arrow 15 by the self-assembly characteristics.

As shown in Figures 2a to 2c, various nanostructures can be formed using the self-assembly of the DNA molecules. This technique is specifically described in US Patent 6,946,675 (MICROELECTRONIC COMPONENTS AND ELECTRONIC NETWORKS COMPRISING DNA, registered on September 20, 2005), disclosed by Erez Braun et al., US Patent 6,255,469 (PERIODIC TWO AND THREE DIMENSIONAL NUCLEIC ACID STR06TURES 2001. .03 registered) and Paul WK US Patent Publication No. 2007/0117109 disclosed by Rothemund (NANOSTRUCTURES, published METHODS OF MAKING AND USING THE SAME, published 24 May 2007) and the detailed description thereof will be omitted.

Next, as an embodiment of the present invention will be described for the etching process of the nano device using a nanostructure having a self-assembly.

3A to 3D are views illustrating an etching process using a nanostructure according to an embodiment of the present invention, and FIG. 4 is an AFM photograph of a nanowire formed on a DNA nanostructure according to an embodiment of the present invention.

As shown in FIG. 3A, the method of forming a nano device according to the first embodiment of the present invention includes forming a nanoscale self-assembly material layer 23 on a substrate 21 having at least one layer. do. As described above, the self-assembled material layer 23 may be formed of a DNA molecule using a property that four different bases complementarily bind to each other. In other words, the self-assembled material layer 23 may be patterned on the substrate 21 at a nanoscale using self-assembly.

In addition, the self-assembled material layer 23 may be formed of any one material selected from proteins, synthetic polymers, and carbon-based materials. In this case, the protein includes a functional protein such as apoferritin that traps the insulating particles. In addition, the carbon-based material may be any one material selected from carbon nanotubes (CNT), buckyballs, and griffins.

Each of the proteins, synthetic polymers and carbon-based materials are nanopatterned in a different way than DNA molecules formed by complementary binding. In more detail, each of the proteins, synthetic polymers, and carbon-based materials can be patterned on a nanoscale, depending on the particular morphology under specific growth conditions and environments. For example, block copolymers, which are one of the synthetic polymers, and two or more different types of polymer chains forcibly connected through chemical bonds are deposited on a substrate, and then, depending on the heat treatment process and the characteristics of the applied electric field. Nanopatterns can be patterned into the desired shape, such as nanoholes or nanowires.

As shown in FIGS. 3B and 4, a mask layer 25 made of nanoparticles is formed on the self-assembled material layer 23. The mask layer 25 is attached to the self-assembly material layer 23 by functionalizing a surface. The self-assembly material layer 23 formed of the DNA molecule will be described in more detail by way of example. The sugar-phosphate backbone of the self-assembly material layer 23 formed of the DNA molecule is electrically negative as is known. -) Accordingly, an organic monolayer that is positively positive on the surface of each of the nanoparticles constituting the mask layer 25 is formed by a chemical method. Thus, the mask layer 25 is electrically positive (+) through chemical modification. The amount of surface charge of the mask layer 25 may be adjusted in the same manner as described above, and the mask layer 25 may be coupled to the self-assembled material layer 23 patterned on a nano scale by electrical attraction. However, various methods of chemically modifying the surface of each of the nanoparticles constituting the mask layer 25 exist, and may vary according to the type of material constituting the mask layer 25.

FIG. 4 is an Atomic Force Microscopy (AFM) photograph showing gold (Au) nanowires chemically modified and attached to DNA nanostructures formed on a substrate. Thus, the mask layer 25 may be formed of nanoparticles of a semiconductor material, an insulating material, or a magnetic material to be attached to the DNA nanostructure. The mask layer 25 is gold (Au), silver (Ag), silicon (Si), silicon oxide (SiO ₂ ), silicon nitride (SiN), iron (Fe), cadmium selenide (CdSe), carbon nano It may be formed of any one material selected from a tube CNT, a buckyball and a graphene.

On the other hand, when the self-assembled material layer 23 is formed of a protein, for example, a space capable of capturing nanoparticles exists in a spherical protein, and the space may be opened and closed according to heat treatment and various conditions. Therefore, the self-assembly material layer 23 may trap the nanoparticles constituting the mask layer 25 in the space. In addition, when the mask layer 25 is formed of a carbon-based material including synthetic polymers or carbon nanotubes, the nanoparticles constituting the mask layer 25 are self-assembled material layers by electrical attraction through chemical modification. It can be attached to (23). Accordingly, the mask layer 25 is formed in a nanoscale pattern from the self-assembly of the self-assembling material layer 23 without using an exposure process.

As shown in FIGS. 3C and 3D, an etching process such as wet or dry etching is performed on the substrate 21 having the mask layer 25. Thus, the mask layer 25 serves as a mask or an etch stop layer. Next, the self-assembly material layer 23 and the mask layer 25 are removed. The self-assembled material layer 23 and the mask layer 25 may be removed at the same time or selectively. In this case, the mask layer 25 may be removed through a technique well known to those skilled in the art (hereinafter referred to as the person skilled in the art) to which the technology of the present invention belongs.

On the other hand, when the self-assembling material layer 23 is formed of a DNA nanostructure or protein, the self-assembling material layer 23 may be removed by a heat treatment process or an acidic solution carried out at a temperature range of 90 ℃ to 200 ℃. have. In addition, when the self-assembled material layer 23 is formed of a synthetic polymer, it may be removed using a heat treatment process or a chemical agent. When the self-assembled material layer 23 is formed of a carbon-based material including carbon nanotubes, the self-assembled material layer 23 may be removed by a chemical agent that selectively removes carbon-based materials.

Next, the ion implantation process of the nano device according to another embodiment of the present invention will be described. 5A to 5C are views illustrating an ion implantation process using a nanostructure according to another embodiment of the present invention.

As shown in FIGS. 5A to 5C, a nanoscale self-assembly material layer 33 and a mask layer 35 are sequentially formed on at least one layered substrate 31. The ion implantation layer 37 is formed by performing an ion implantation process well known to those skilled in the art on the entire surface of the substrate 31 using the mask layer 35 as a mask. Since the materials forming the self-assembly material layer 33 and the mask layer 35 are as described above, detailed description thereof will be omitted.

As a result, the nano-scale mask layer according to the embodiments of the present invention may serve as a mask or an etch stop layer in a surface treatment process such as an etching process or an ion implantation process.

Next, a method of forming a transistor using a nanostructure according to another embodiment of the present invention will be described. However, the present invention describes a method of forming a semiconductor nano device as an example, but is not limited thereto, and may be widely applied to fabricating a nano device using a nanostructure having self-assembly properties. 6A to 6E are views illustrating a method of forming a transistor using a nanostructure according to another embodiment of the present invention.

6A to 6E, an insulating film 63a and a conductive film 65a are sequentially formed on the substrate 61 having the active region in order to form the transistor 60 according to the exemplary embodiment of the present invention. . The conductive layer 65a may be formed of polysilicon or a metal material. A self-assembled material layer 67 formed of any one material selected from DNA molecules, proteins, synthetic polymers, and carbon-based materials is formed on the conductive film 65a. The conductive layer pattern 65 and the insulating layer pattern 63 are formed by sequentially patterning the conductive layer 65a and the insulating layer 63a using the self-assembled material layer 67 as an etching mask. An ion implantation region 69 is formed on the substrate 61 using the self-assembled material layer 67 as an ion implantation mask. After forming the ion implantation region 69, the self-assembled material layer 67 is removed.

In the case where the self-assembled material layer 67 is formed of DNA nanostructure or protein, the self-assembled material layer 67 may be removed by a heat treatment process or an acid solution performed at a temperature range of 90 ° C to 200 ° C. . In addition, when the self-assembled material layer 67 is formed of a synthetic polymer, it may be removed using a heat treatment process or a chemical agent. When the self-assembled material layer 67 is formed of a carbon-based material including carbon nanotubes, the self-assembled material layer 67 may be removed by a chemical agent that selectively removes carbon-based materials.

The spacer layer 71 is formed on sidewalls of the conductive layer pattern 65 and the insulating layer pattern 63. Accordingly, the transistor 60 having a nano standard may be manufactured using the self-assembling material layer 67. In addition, the self-assembled material layer 67 according to the present invention can be used to fabricate wiring on an interlayer insulating film, such as a nano-scale bit line or a metal wiring, and a nano-sized fin field effect transistor (FinFET) or phase change. It may also be used for cell patterning of memory (PRAM) devices.

Although the invention made by the present inventors has been described in detail with reference to the manufacture of a semiconductor device as an example, the present invention is not limited to the above embodiments and has a self-assembly characteristic in a range that does not depart from the gist thereof. Of course, it can be changed in various ways, such as the production of nano devices using the structure.

In the drawings, the thicknesses of layers and regions are exaggerated for clarity. Also, an element or layer is referred to as "on" or "on" of another element or layer by interposing another layer or other element in the middle as well as directly above the other element or layer. Include all cases.

The present invention relates to a method of forming a nano device. For example, the method of forming the nanodevice may be applied to a semiconductor device including a photonic crystal device, a magnetic device, an information recording medium, a solar cell, or a nanometer nanometer transistor. In addition, the nanostructure having the self-assembly according to the present invention can be applied to a variety of processes, such as manufacturing a nano device, such as nano actuators and nano robots.

21: substrate 23: self-assembled material layer
25: mask layer

Claims (6)

Forming a nanoscale layer of self-assembled material on the substrate of at least one layer;
Forming a mask layer on the self-assembled material layer;
Performing a surface treatment process on the substrate using the mask layer as a mask; And
Removing the self-assembled material layer. The method of claim 1, wherein the surface treatment process
Method of forming a nano device, characterized in that the etching process or ion implantation process. The method of claim 1, wherein the mask layer
Gold (Au), silver (Ag), silicon (Si), silicon oxide (SiO ₂ ), silicon nitride (SiN), iron (Fe), cadmium selenide (CdSe), carbon nanotubes (CNT), buckyballs ( Method for forming a nano device, characterized in that it comprises any one material selected from buckyball) and griffin (Graphine). The method of claim 1,
The self-assembling material layer is a method of forming a nano device, characterized in that it comprises any one material selected from DNA molecules, proteins, synthetic polymers and carbon-based materials. The method of claim 4, wherein the carbon-based material
Carbon nanotube (CNT), Buckyball (buckyball) and Griffin (Graphine) a method for forming a nano device comprising any one material selected from. The method of claim 4, wherein
Each of the DNA molecule and the protein is removed by a heat treatment process or an acid solution, the synthetic polymer is removed using a heat treatment process or a chemical agent, the carbon-based material is removed with a chemical agent to selectively remove the carbon-based material Method of forming a nano device, characterized in that.

Images