A high-quality wafer-level single-oriented two-dimensional bismuth selenide vertical fin array batch preparation method

Abstract

The application discloses a method for batch preparing a wafer-level single-oriented two-dimensional Bi2O2Se vertical fin (Fin) array. The method comprises the following steps: taking an oxide MgO (110) single crystal wafer as a substrate, using Bi2O3 powder, Bi2Se3 bulk and high-purity argon / oxygen mixed gas as raw materials to perform chemical vapor deposition, and obtaining the two-dimensional Bi2O2Se vertical Fin array wafer after the deposition is completed. The method is economical and simple in process, and the obtained wafer-level single-oriented two-dimensional Bi2O2Se vertical Fin array has a wide application prospect.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor material preparation and chemical vapor deposition (CVD) technology, specifically relating to a method for the mass production of a single-orientation array of high-quality wafer-level two-dimensional bismuth selenide oxide vertical fins (Fin), which is suitable for large-scale mass production of wafer-level single-orientation two-dimensional bismuth selenide oxide vertical fin (Fin) arrays. Background Technology

[0002] Two-dimensional bismuth selenide oxide (Bi₂O₂Se) is a novel, environmentally stable, high-mobility semiconductor material composed of (Bi₂O₂). n Layers and Se n Alternating connections form a two-dimensional layered crystal structure with fourfold symmetry. Z=2). The unique crystal and band structure of the environmentally stable two-dimensional Bi₂O₂Se semiconductor endows it with excellent electrical, optical, and optoelectronic physicochemical properties, showing broad application prospects in logic circuits, memristors, ultrafast infrared detection, photocatalysis, and gas detection. As a high-mobility two-dimensional layered semiconductor, Bi₂O₂Se has an intrinsic mobility as high as 28900 cm⁻¹ at 2K. 2 V -1 s -1 The room temperature field-effect electron mobility is as high as 2200 cm⁻¹. 2 V -1 S -1 With a subthreshold swing as low as 65mV / dec, it may be applied to high-performance, low-power nano-logic devices.

[0003] Under the International Devices and Systems Roadmap (IRDS), the channel architecture of key transistor units in semiconductor integrated circuits has shifted from planar channels to vertical fins (Fins) to further enhance transistor gate control, increase drive current, and improve integration density. Currently, two-dimensional Bi₂O₂Se semiconductors obtained through chemical vapor deposition (CVD) are mainly in-plane growth crystals or thin films attached to the substrate surface, with limited application of self-supporting vertical fins (Fins), making it difficult to meet the future needs of the electronics and optoelectronics fields. Tan Congwei et al. used an oxidation method and chemical vapor deposition (CVD) to synthesize self-supporting Bi₂O₂Se two-dimensional single crystals detached from the substrate surface on mica and perovskite oxide substrates. However, due to the random orientation of the self-supporting Bi₂O₂Se two-dimensional crystals and the lack of a single orientation, it is difficult to meet practical application requirements. Therefore, the controllable synthesis of large-area, single-orientation, high-quality two-dimensional vertical fins is the key and challenge for the future large-scale application of two-dimensional semiconductor Bi₂O₂Se materials. However, to date, there have been no reports on the synthesis and mass production of high-quality wafer-level single-orientation two-dimensional Bi2O2Se vertical fin arrays. Summary of the Invention

[0004] The purpose of this invention is to provide a method for fabricating high-quality, single-oriented bismuth selenide oxide two-dimensional vertical Fin arrays and achieving wafer-level mass production. This method offers excellent controllability, a simple process flow, and low cost, making it a reliable method for large-scale fabrication of single-oriented bismuth selenide oxide two-dimensional vertical Fin arrays.

[0005] The method for mass production of wafer-level single-orientation two-dimensional Bi2O2Se vertical fin (Fin) arrays provided by the present invention includes the following steps: using a magnesium oxide (110) single crystal wafer as a growth substrate, Bi2Se3 single crystal bulk, Bi2O3 powder and high-purity argon / oxygen mixed gas as raw materials, chemical vapor deposition is performed to obtain the two-dimensional Bi2O2Se vertical Fin array.

[0006] In the above chemical vapor deposition method, the mass ratio of Bi2O3 powder to Bi2Se3 bulk is 7:6-2:1.

[0007] The volume ratio of argon to oxygen in the high-purity argon / oxygen mixture is 150000:1-15000:1.

[0008] The chemical vapor deposition was performed on a magnesium oxide (110) single crystal wafer substrate;

[0009] The wafer substrate is specifically a magnesium oxide (110) single crystal wafer with the chemical formula MgO.

[0010] The wafer substrate has a size of 1 inch.

[0011] In the chemical vapor deposition step, the carrier gas is argon.

[0012] The argon flow rate is 200-400 sccm, specifically 200, 300, or 400 sccm.

[0013] The system pressure is 350-450 torr, specifically 350, 400 or 450 torr.

[0014] The deposition temperature is 620-690℃, specifically 620℃, 630℃, 640℃, 650℃, 660℃, 670℃, 680℃ or 690℃.

[0015] The deposition time is 1-3 minutes, specifically 1, 2 or 3 minutes.

[0016] The chemical vapor deposition can be carried out in a tube furnace;

[0017] The diameter of the tube furnace is 1-4 inches, specifically 1, 2, 3 or 4 inches.

[0018] More specifically, the raw material is located at the center of the tubular furnace.

[0019] The wafer substrate is located in the central temperature zone of the tube furnace.

[0020] The method further includes the following step: after the chemical vapor deposition step, the system is rapidly cooled to room temperature.

[0021] Figure 1 This is a schematic diagram of the method for growing a single-oriented two-dimensional Bi₂O₂Se vertical Fin array according to the present invention. The two-dimensional Bi₂O₂Se vertical Fin array is obtained by nucleating the vertically oriented Bi₂O₂Se on a double-symmetric ionic substrate, and the vertical nuclei can be further grown to obtain a single-oriented two-dimensional Bi₂O₂Se Fin array.

[0022] Figure 2 This is a crystal structure diagram of Bi2O2Se and ionic magnesium oxide (110) substrate described in this invention.

[0023] Figure 3 This is a schematic diagram of the growth of a two-dimensional Bi2O2Se vertical Fin array by chemical vapor deposition according to the present invention.

[0024] The wafer-level single-orientation two-dimensional Bi2O2Se vertical Fin array prepared by the above method, and its application in the construction of Fin field-effect transistors (FinFETs) based on the two-dimensional Bi2O2Se vertical Fin array, are also within the scope of protection of this invention.

[0025] The specific Hall mobility of the wafer-level Bi2O2Se vertical Fin at 2K can be 24000 cm⁻¹. 2 V -1 s -1 .

[0026] In this invention, wafer-level, single-oriented two-dimensional Bi₂O₂Se vertical Fin arrays prepared by this chemical vapor deposition method can reach a size of 1 inch, which is the largest commercially available substrate size. This method is simple, and the resulting high-density vertical Fin arrays have high mobility, showing broad application prospects in the semiconductor field.

[0027] Compared with the prior art, the present invention has the following beneficial technical effects:

[0028] 1. This invention employs chemical vapor deposition technology, using MgO(110) single crystal wafers as growth substrates, and utilizes the symmetry matching and ion-polarity interaction between double-symmetric MgO(110) and double-symmetric Bi2O2Se(100) to grow a single-oriented two-dimensional Bi2O2Se vertical Fin array.

[0029] 2. The process of this invention is simple, economical, and highly controllable, and it is expected to enable the large-scale production of wafer-level single-orientation two-dimensional Bi2O2Se vertical Fin arrays; laying the foundation for the application of single-orientation two-dimensional Bi2O2Se vertical Fin arrays in advanced transistor architectures (FinFET, vertical transmission field-effect transistor, etc.). Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the method for growing a single-oriented two-dimensional Bi2O2Se vertical Fin array according to the present invention.

[0031] Figure 2 The crystal structure diagrams of Bi2O2Se and MgO described in this invention are shown below;

[0032] Figure 3 This is a schematic diagram of the chemical vapor deposition system for growing a single-oriented two-dimensional Bi2O2Se vertical Fin array according to the present invention;

[0033] Figure 4 These are optical and SEM images of a single-orientation two-dimensional Bi2O2Se vertical Fin array wafer grown according to the present invention.

[0034] Figure 5 This is the Hall mobility curve after the vertical Fin transfer of a single-oriented two-dimensional Bi2O2Se grown according to the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments. Unless otherwise specified, the methods described are conventional methods. Unless otherwise specified, the raw materials are all available from publicly available commercial sources.

[0036] Example 1

[0037] Weigh 3.0 g of Bi₂O₃ powder and 2.0 g of Bi₂Se₃ bulk and place them in the center of the quartz tube of the tube furnace. Next, place a 1-inch MgO(110) single crystal wafer in the center of the tube furnace. Introduce a high-purity argon / oxygen mixture as the carrier gas, with an argon to oxygen volume ratio of 75000:1, and maintain the system pressure at 350 torr. Raise the temperature to 640°C and maintain it for 2 minutes to perform chemical vapor deposition. After deposition, stop the carrier gas supply, allow it to cool naturally to 300°C, and then rapidly air-cool it to room temperature. Remove the MgO(110) wafer with the two-dimensional Bi₂O₂Se vertical Fin array deposited on it, thus obtaining the two-dimensional Bi₂O₂Se vertical Fin array wafer provided by this invention.

[0038] Figure 4The image shows a SEM image of a two-dimensional Bi2O2Se vertical fin array grown on a MgO(110) single crystal wafer in this embodiment. As can be seen from the image, the obtained two-dimensional Bi2O2Se vertical fins are square nanosheets with a single orientation and are strictly perpendicular to the substrate surface.

Claims

1. A method for mass production of wafer-level single-orientation two-dimensional Bi₂O₂Se vertical fin arrays, characterized in that: The two-dimensional Bi2O2Se vertical Fin array is obtained by inducing vertical orientation nucleation on a double-symmetric ionic substrate and growing vertical nuclei to obtain a single-oriented two-dimensional Bi2O2Se Fin array. The method includes the following steps: using a magnesium oxide (110) single crystal wafer as a growth substrate, Bi2Se3 single crystal bulk, Bi2O3 powder and high-purity argon / oxygen mixed gas as raw materials, chemical vapor deposition is performed, and after deposition, the wafer-level single-oriented two-dimensional Bi2O2Se vertical fin array is obtained. The chemical vapor deposition is performed in a tube furnace; the raw material is located at the center of the tube furnace; and the wafer substrate is located in the central temperature zone of the tube furnace.

2. The method according to claim 1, characterized in that: In the chemical vapor deposition method, the mass ratio of Bi2O3 powder to Bi2Se3 single crystal bulk is 7:6-2:1; The volume ratio of argon to oxygen in the high-purity argon / oxygen mixture is 150000:1-15000:

1.

3. The method according to claim 1 or 2, characterized in that: The wafer substrate has a size of 1 inch.

4. The method according to claim 1 or 2, characterized in that: In the chemical vapor deposition step, the carrier gas is argon. The argon gas flow rate is 200-400 sccm; The system pressure is 350-450 torr; The deposition temperature is 620-690℃; The deposition time is 1-3 minutes.

5. The method according to claim 1 or 2, characterized in that: The tube furnace has a tube diameter of 1–4 inches.

6. The method according to claim 1 or 2, characterized in that: The method further includes the following step: after the chemical vapor deposition step, the system is rapidly cooled to room temperature.

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