Diode device based on carbon nanotube structure
By forming metal ends and semiconductor ends on a single carbon nanotube, or forming p-type and n-type semiconductor ends, a stable Schottky junction or p-n junction is solved, and a nanoscale diode with high performance and low power consumption is achieved.
Patent Information
- Application Number
- CN202421537157.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-02
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-07-02
AI Technical Summary
The formation of stable metal material parts and semiconductor materials in the same nanotube is difficult to form stable Schottky junctions or p-n junctions, limiting the performance and application of nanoscale diodes.
By forming the metal end and the semiconductor end on a single carbon nanotube, a stable Schottky junction is constructed, or a p-type semiconductor end is formed at one end of a single carbon nanotube and an n-type semiconductor end is formed at the other end, a stable p-n junction is constructed.
Schottky diodes and p-n junction diodes with high performance and low power consumption at the nanoscale are achieved, breaking through the size limitations of existing semiconductor processes on the nanoscale and having ideal diode rectification characteristics.
Smart Images
Figure CN223024885U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of electronic devices, in particular to a diode device based on a carbon nanotube structure. Background Technique
[0002] With the development of integrated circuits towards higher density, lower power consumption and higher speed, traditional semiconductor materials and devices face performance limitations brought by size effects. Nanoscale diodes are thinner, smaller, more efficient and have extremely low power consumption, which can meet the large computing power requirements needed for future artificial intelligence chips and machine learning. Single nanotube diodes are nanoscale in size and are suitable for extremely miniaturized electronic devices. Due to their excellent electrical, mechanical and thermal properties, they have become ideal candidates for next-generation electronic devices. The electron mobility of single carbon nanotubes is very high, far exceeding that of traditional semiconductor materials, enabling high-speed switching and fast response. Moreover, the conductivity of single carbon nanotubes is close to that of metals, giving them obvious advantages in low-resistance applications. They also have characteristics such as high strength and flexibility, efficient electron-hole recombination characteristics, low power consumption and low noise, making single carbon nanotube diodes have broad application prospects in future microelectronics, nanoelectronics, optoelectronic devices, high-performance devices, sensors and flexible electronic devices.
[0003] The synthesis technology of carbon nanotubes has been continuously optimized, and single carbon nanotubes with high purity, single chirality and high crystallinity can be prepared. These high-quality carbon nanotubes lay the foundation for the improvement of device performance. By using micro-nano processing technologies such as high-precision electron beam lithography and chemical vapor deposition, efficient contact between carbon nanotubes and electrodes can be achieved.
[0004] The design difficulty of single nanotube diodes lies in that it is difficult to form a stable Schottky junction or p-n junction between the metal material part and the semiconductor material in the same nanotube.
[0005] It should be noted that the information disclosed in the above background technique part is only used for understanding the background of the present application, and therefore may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Utility Model
[0006] The main purpose of the present utility model is to overcome the defects of the above background technique and provide a diode device based on a carbon nanotube structure.
[0007] To achieve the above purpose, the present utility model adopts the following technical solutions:
[0008] In the first aspect of the present utility model, a diode device based on a carbon nanotube structure includes:
[0009] A single carbon nanotube with a radius of 0.4 - 30 nm;
[0010] A metal end, which is formed by axially partially cutting one end of the carbon nanotube, has metallic properties and there is no bandgap in its energy band structure;
[0011] A semiconductor end, which is formed by the other end of the carbon nanotube, maintains the complete chirality, has semiconductor properties, and there is a bandgap greater than 0 in its energy band structure;
[0012] A Schottky junction, which is formed at the contact interface between the metal end and the semiconductor end. A depletion region is formed at the interface. Under forward bias conditions, it allows current to flow from the metal end to the semiconductor end. Under reverse bias conditions, due to the potential barrier formed by the depletion region, it blocks the current from passing through;
[0013] Electrodes, which are assembled on the metal end and the semiconductor end.
[0014] Furthermore, the carbon nanotube has chirality (n,m), where m = 0 or n - m ≠ 3q, n and m are integers, q is an integer, and n > m.
[0015] In the second aspect of the present utility model, a diode device based on a carbon nanotube structure includes:
[0016] A single carbon nanotube with a radius of 0.4 - 30 nm;
[0017] A p-type semiconductor end, which is formed by one end of the carbon nanotube and has p-type semiconductor properties due to a boron-doped carbon nanotube structure;
[0018] An n-type semiconductor end, which is formed by axially partially cutting the other end of the carbon nanotube and has n-type semiconductor properties;
[0019] A p-n junction, which is formed at the contact interface between the p-type semiconductor end and the n-type semiconductor end. A depletion region is formed at the interface. Under forward bias conditions, it allows current to flow from the n-type semiconductor end to the p-type semiconductor end. Under reverse bias conditions, due to the potential barrier formed by the depletion region, it blocks the current from passing through;
[0020] Electrodes, which are assembled on the p-type semiconductor end and the n-type semiconductor end.
[0021] Furthermore, the carbon nanotube has chirality (n,m), where m = 0 or n - m ≠ 3q, n and m are integers, q is an integer, and n > m.
[0022] The present utility model has the following beneficial effects:
[0023] The present utility model proposes a diode device based on a carbon nanotube structure, which successfully realizes high-performance and low-power Schottky diodes and p-n junction diodes at the nanoscale. This design forms a metal end and a semiconductor end on a single carbon nanotube, and then constructs a stable Schottky junction. Or a p-type semiconductor end is formed at one end of a single carbon nanotube, and an n-type semiconductor end is formed at the other end, and then a stable p-n junction is constructed. The diode device based on the carbon nanotube structure of the present utility model not only breaks through the size limitation of the existing semiconductor process at the nanoscale, but also solves the problem of forming regions with different conductive properties on the same nanotube, realizing a nanoscale diode device with a diameter less than a few nanometers, or even less than one nanometer, breaking through the size bottleneck of the existing semiconductor process at the nanoscale. In addition, the diode device of the present utility model exhibits low impedance when forward-biased, allowing current to pass smoothly, and exhibits high impedance due to the potential barrier formed by the depletion region when reverse-biased, thus possessing the ideal diode rectification characteristics. This innovative device solution provides new possibilities for applications in the fields of microelectronics, nanoelectronics, etc., and is expected to promote the development and application of related technologies.
[0024] Other beneficial effects in the embodiments of the present utility model will be further described below. Brief Description of the Drawings
[0025] Figure 1 It is a schematic structural diagram of a Schottky diode device based on a single carbon nanotube according to an embodiment of the present utility model.
[0026] Figure 2 It is a band structure diagram of the Schottky diode positive electrode trimmed carbon nanotube according to an embodiment of the present utility model.
[0027] Figure 3 It is a band structure diagram of the Schottky diode negative electrode complete carbon nanotube according to an embodiment of the present utility model.
[0028] Figure 4 It is a schematic structural diagram of a p-n diode device based on a single carbon nanotube according to an embodiment of the present utility model.
[0029] Figure 5 It is a band structure diagram of the p-n junction diode anode trimmed carbon nanotube n-type semiconductor according to an embodiment of the present utility model.
[0030] Figure 6 It is a band structure diagram of the p-n junction diode boron-doped cathode carbon nanotube p-type semiconductor according to an embodiment of the present utility model. Detailed Embodiments
[0031] The following provides a detailed description of the embodiments of the present utility model. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present utility model.
[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. Additionally, the connection can be for a fixing function or for a coupling or communicating function.
[0033] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present utility model.
[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present utility model, the meaning of "a plurality" is two or more unless otherwise specifically defined.
[0035] The embodiments of the present utility model propose a diode device based on a single carbon nanotube, which realizes a metal end and a semiconductor end on the same carbon nanotube, constructs a stable Schottky junction or p-n junction, and can be used to manufacture extremely miniaturized electronic devices. In a single carbon nanotube, there is a p-n junction or a Schottky junction in the middle of the carbon tube, and the entire structure can be used to fabricate a carbon nanotube diode. Such a diode can be used for rectification and other non-linear elements in electronic circuits.
[0036] Refer to Figure 1, an embodiment of the present utility model provides a diode device based on a carbon nanotube structure, including: a single carbon nanotube; a metal end 1, formed by axially partially cutting one end of the carbon nanotube, having metallic properties and no bandgap in its energy band structure; a semiconductor end 3, formed by the other end of the carbon nanotube, maintaining the complete chirality, having semiconductor properties and having a bandgap greater than 0 in its energy band structure; a Schottky junction 2, formed at the contact interface between the metal end 1 and the semiconductor end 3, with a depletion region formed at the interface, and allowing current to flow from the metal end to the semiconductor end under forward bias conditions, while under reverse bias conditions, due to the potential barrier formed by the depletion region, preventing current from passing through; an electrode (not shown), assembled on the metal end 1 and the semiconductor end 2.
[0037] The Schottky junction 2 is an interface formed by the direct contact between the metal end 1 and the semiconductor end 3. At this interface, due to the different work functions of the two materials, electrons are redistributed at the interface, thus forming a depletion region. The device of this embodiment can form a diode through the formation of the Schottky junction 2.
[0038] For a single-layer chiral carbon nanotube, when the chiral vector is m = 0 or n - m ≠ 3q (q is an integer and n > m), the properties of the carbon nanotube are semiconductor properties. When the carbon nanotube is cut axially to form a curved nanoribbon or a line defect, due to the dangling electrons of the edge atoms, the carbon nanotube is transformed into metallic properties. A complete carbon nanotube and a cut carbon nanotube part are included in the single carbon nanotube, and a stable Schottky junction can be formed at the connection of these two parts.
[0039] As Figure 1 shown, in the diode device based on a single carbon nanotube in the embodiment, the metal end 1 and the semiconductor end 2 of the diode are based on the same carbon nanotube. The metal end 1 has a curved nanoribbon cut axially. The semiconductor end 2 is a complete chiral carbon nanotube. The metal end 1 is the anode (positive electrode), and the semiconductor end 2 is the cathode (negative electrode). The semiconductor end 2 is in contact with the metal end 1. The chirality of the semiconductor carbon nanotube is (n, m), and the types include m = 0 and carbon nanotubes with n - m ≠ 3q (q is an integer and n > m) and a radius of 0.4 - 30 nm.
[0040] Refer to Figure 4, an embodiment of the present utility model also provides a p-n junction diode device based on a single carbon nanotube structure, including: a single carbon nanotube having different conductive property regions; a p-type semiconductor end 6 formed at one end of the carbon nanotube, being a boron-doped carbon nanotube structure and having p-type semiconductor properties; an n-type semiconductor end 4 formed by axially partially cutting one end of the carbon nanotube, having n-type semiconductor properties; a p-n junction 5 formed at the contact interface between the p-type semiconductor end 6 and the n-type semiconductor end 4, with a depletion region formed at the interface, and allowing current to flow from the n-type semiconductor end 4 to the p-type semiconductor end 6 under forward bias conditions, while under reverse bias conditions, due to the potential barrier formed by the depletion region, preventing current from passing through; an electrode (not shown) assembled on the p-type semiconductor end 6 and the n-type semiconductor end 4.
[0041] When a p-type semiconductor and an n-type semiconductor come into contact, due to the recombination of electrons and holes, a p-n junction will be formed at the interface. The formed p-n junction exhibits low impedance under forward bias and high impedance under reverse bias, which is the basic structure of semiconductor devices such as diodes.
[0042] For a single-layer chiral carbon nanotube, when the chiral vector m = 0 or n - m ≠ 3q (q is an integer and n > m), the property of the carbon nanotube is semiconductor. When an electric field is applied to the axially cut carbon nanotube, due to the movement of electrons, the material will exhibit n-type semiconductor properties. Boron-doped carbon nanotubes exhibit P-type semiconductor properties due to the lack of valence electrons. The combination of n-type and P-type semiconductors can form a p-n junction.
[0043] The p-n junction diode device based on a single carbon nanotube proposed by the present utility model can be used to realize extremely miniaturized electronic devices.
[0044] Example 1
[0045] Figure 1 An example is the Schottky diode structure design based on a single carbon nanotube. The structure includes a carbon nanotube, with one end being a complete nanotube structure and the other end being an axially cut nanotube structure (the structure is close to a curled nanoribbon). Figure 1 The positive end shown is the axially cut nanotube, with metallic properties (as Figure 2 shown, the energy band gap disappears after cutting and transforms into metallicity). Figure 1 The negative end shown is a complete nanotube structure, with semiconductor conductive properties (as Figure 3 shown, the energy band has a 1.1 eV band gap and is a semiconductor). Figure 1The Schottky junction shown is formed by connecting a metal material as the positive electrode and a semiconductor material as the negative electrode, and the potential barrier formed at the interface is about 1 eV. When forward-biased, the current flows from the metal end (positive electrode) to the semiconductor end (negative electrode), that is, the current flows out from the negative electrode and the diode conducts. When reverse-biased, due to the potential barrier of the Schottky junction, the current is blocked and almost no current passes through the diode, and the diode is cut off.
[0046] Example 2
[0047] Figure 4 An example is the design of a p-n junction diode structure based on a single carbon nanotube. The structure includes a single carbon nanotube, with a boron-doped carbon nanotube structure at one end, and the conductive property is that of a p-type semiconductor; the other end is an axially truncated nanotube structure (the structure is close to a curled nanoribbon). Figure 4 As shown, the positive electrode end is an axially truncated carbon nanotube. Due to the additional dangling electrons introduced by the truncation, its property in an electric field is that of an n-type conductive material. As Figure 5 shown, the truncated structure causes the energy band of the material to shift downward in the electric field, showing the property of a semiconductor with majority charge carriers. Figure 4 As shown, the negative electrode end is a boron-doped complete nanotube structure, and the conductive property is that of a p-type semiconductor. As Figure 6 shown, the doping of boron atoms causes the energy band to shift upward, showing the property of a semiconductor with majority holes. Figure 4 The p-n junction shown is formed by connecting an n-type material as the positive electrode and a p-type semiconductor material as the negative electrode, and a p-n junction with the mutual cancellation of charge carriers and hole carriers is formed at the interface. When forward-biased, the current flows from the n-type semiconductor end (positive electrode) to the p-type semiconductor end (negative electrode), that is, the current flows out from the negative electrode and the diode conducts. When reverse-biased, due to the depletion layer of the p-n junction, the current is blocked and almost no current passes through the diode, and the diode is cut off.
[0048] Electrode assembly:
[0049] Locate the position of a single carbon nanotube and record it. Conduct electrode design to ensure that the electrode contact area coincides with the carbon nanotube. Select a suitable electrode material (such as gold, platinum, chromium, titanium, etc.) to ensure good contact with the carbon nanotube.
[0050] In summary, the present utility model proposes a diode device based on a carbon nanotube structure, which successfully realizes high-performance and low-power Schottky diodes and p-n junction diodes at the nanoscale. This design forms a metal end and a semiconductor end on a single carbon nanotube, thereby constructing a stable Schottky junction, or forms a p-type semiconductor end at one end of a single carbon nanotube and an n-type semiconductor end at the other end, thereby constructing a stable p-n junction. The diode device based on the carbon nanotube structure of the present utility model not only breaks through the size limitation of the existing semiconductor process at the nanoscale, but also solves the problem of forming regions with different conductive properties on the same nanotube, realizing a nanoscale diode device with a diameter less than a few nanometers, or even less than one nanometer, breaking through the size bottleneck of the nanoscale of the existing semiconductor process. In addition, the diode device of the present utility model exhibits low impedance when forward-biased, allowing current to flow smoothly, and high impedance when reverse-biased due to the potential barrier formed by the depletion region, thus possessing the ideal rectifying characteristics of a diode. This innovative device solution provides new possibilities for applications in the fields of microelectronics, nanoelectronics, etc., and is expected to promote the development and application of related technologies.
[0051] The above content is a further detailed description of the present utility model in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present utility model is only limited to these descriptions. For those of ordinary skill in the technical field to which the present utility model belongs, without departing from the concept of the present utility model, several alternatives or modifications can be made to these described embodiments, and these alternative or modified forms should all be regarded as belonging to the protection scope of the present utility model. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. Without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present utility model and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of protection of the patent application.
Claims
1. A diode device based on a carbon nanotube structure, characterized in that: include: Single carbon nanotube, radius 0.4-30nm; The metal end is formed by partially cutting one end of the carbon nanotube along the axial direction, has metallic properties, and has no band gap in its energy band structure; The semiconductor end is formed by the other end of the carbon nanotube, maintains complete chirality, has semiconductor properties, and has a band gap greater than 0 in its energy band structure; A Schottky junction is formed at the contact interface between the metal terminal and the semiconductor terminal, a depletion region is formed at the interface, and under forward bias conditions, current is allowed to flow from the metal terminal to the semiconductor terminal, while under reverse bias conditions, the potential barrier formed by the depletion region prevents the current from passing; Electrodes are assembled on the metal end and the semiconductor end.
2. The diode device based on the carbon nanotube structure according to claim 1, characterized in that: The carbon nanotubes have chirality (n, m), m=0 or nm≠3q, wherein n and m are integers, q is an integer, and n>m.
3. A diode device based on a carbon nanotube structure, characterized in that: include: Single carbon nanotube, radius 0.4-30nm; A p-type semiconductor end, formed by one end of the carbon nanotube, is a boron-doped carbon nanotube structure and has p-type semiconductor properties; An n-type semiconductor end is formed by partially cutting the other end of the carbon nanotube along the axial direction and has n-type semiconductor properties; A pn junction is formed at the contact interface between the p-type semiconductor terminal and the n-type semiconductor terminal, a depletion region is formed at the interface, and under forward bias conditions, current is allowed to flow from the n-type semiconductor terminal to the p-type semiconductor terminal, while under reverse bias conditions, the potential barrier formed by the depletion region prevents the current from passing; The electrodes are assembled on the p-type semiconductor end and the n-type semiconductor end.
4. The diode device based on a carbon nanotube structure as claimed in claim 3, characterized in that: The carbon nanotubes have chirality (n, m), m=0 or nm≠3q, wherein n and m are integers, q is an integer, and n>m.