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CN-122003105-A - Compound film heterojunction and preparation method and application thereof

CN122003105ACN 122003105 ACN122003105 ACN 122003105ACN-122003105-A

Abstract

The invention discloses a compound thin film heterojunction, a preparation method and application thereof, and belongs to the technical field of semiconductor manufacturing and nano materials. The preparation method comprises the steps of providing a substrate with an A x B y film, wherein A is a metal element, B is a chalcogen element, carrying out ion irradiation on the A x B y film by utilizing an ion beam, selectively removing a specific element B preferentially by utilizing the difference of intrinsic sputtering yields of different elements in the film by utilizing the ion beam, thereby actively constructing a controllable component gradient in the depth direction of the film, and when a local component reaches a phase change critical point, namely, inducing phase change in situ in the film to form a vertical heterojunction with an atomic diffusion interface. The method is completed in one step, the process is simple, the heterojunction position can be accurately regulated and controlled through irradiation parameters, and the obtained heterojunction can be used for preparing semiconductor devices such as high-speed transistors, laser diodes, photoelectric detectors, solar cells and the like.

Inventors

  • ZHANG YONGCHAO
  • CHENG SHAOBO
  • XIE LILIN
  • LI YUEHUI

Assignees

  • 河南省科学院量子材料与物理研究所
  • 郑州大学

Dates

Publication Date
20260508
Application Date
20260206

Claims (7)

  1. 1. The in-situ preparation method of the compound film heterojunction is characterized by comprising the following steps of: S1, providing a substrate with an A x B y film, wherein an element A is a metal element, and an element B is a chalcogen element, an initial phase of the A x B y film is a first phase, and the numerical ratio of x to y is 0.1-10:1; S2, irradiating the A x B y film by adopting an ion beam, wherein the energy of the ion beam is different in sputtering yield of the element A and the element B, so that the element B is selectively and preferentially removed, a continuous component gradient with increasing concentration of the element A and decreasing concentration of the element B from the surface of the film to the inside is obtained, when a local component reaches a phase transition critical point, the area is induced to generate phase transition, a second phase close to the surface layer of the film is formed, and the first phase and the second phase are connected through the continuous component gradient to form a vertical heterojunction.
  2. 2. The method for in-situ preparation of a compound thin film heterojunction according to claim 1, wherein the thickness of the A x B y thin film is 5-500 nm.
  3. 3. The method for in-situ preparation of a thin film heterojunction of a compound according to claim 1, wherein the metal element is Cu, ag or Au, and the chalcogen element is S, se or Te.
  4. 4. The method of in-situ preparation of a compound thin film heterojunction according to claim 1, wherein in the step S2, the ion beam is Ga + ion beam, the energy is 10-50 keV, the irradiation dose of the ion beam is 1X 1022-1X 102 5 ions/cm2, and the incident angle is 0-80 degrees.
  5. 5. A compound thin film heterojunction prepared by the method as claimed in any one of claims 1 to 4, which is characterized by comprising a binary compound thin film, wherein the binary compound thin film comprises a second phase positioned on a surface layer and a first phase positioned at the bottom, the second phase is formed by inducing component gradient phase transition through ion irradiation from the first phase, and atomic-level connection is realized between the two phases through continuous component gradient.
  6. 6. Use of a compound thin film heterojunction as defined in claim 5 in the manufacture of a semiconductor device.
  7. 7. The method of claim 6, wherein the semiconductor device comprises a high-speed transistor, a laser diode, a photodetector, or a solar cell.

Description

Compound film heterojunction and preparation method and application thereof Technical Field The invention belongs to the technical field of semiconductor manufacturing and nano materials, and particularly relates to a compound thin film heterojunction, a preparation method and application thereof. Background Heterojunction is used as a core building block of modern semiconductor devices (such as high-speed transistors, laser diodes, photodetectors and solar cells), and the interface quality directly determines the performance limit of the device. Conventional heterojunction fabrication techniques mainly follow two major paths, but all suffer from inherent limitations that are difficult to overcome. Layer-by-layer epitaxial growth techniques (e.g., molecular beam epitaxy MBE, chemical vapor deposition CVD) such methods form heterojunctions by sequentially epitaxially growing layers of different materials on different substrates. Although a single crystal interface of high quality can be obtained, the drawbacks are extremely remarkable. First, the process requirements are extremely demanding, often requiring ultra-high vacuum environments, precise lattice matching, and complex in-situ monitoring systems, resulting in prohibitively high equipment investment and manufacturing costs. Secondly, the growth process is limited by thermodynamic compatibility between materials, and many material combinations with excellent performance but larger lattice mismatch are difficult to realize high-quality epitaxy, thus limiting the material selection range. Furthermore, the layer-by-layer growth is a serial process, the production efficiency is low, and the requirement of large-scale integrated application is difficult to meet. Physical stacking and transfer techniques to overcome the limitations of lattice matching, mechanical lift-off and precision stacking techniques have been developed to manually stack pre-independently prepared two-dimensional materials or films into heterojunctions. This approach, while relaxing the material selection limitations, introduces a new problem, interface contamination. Polymer residues, adsorbed gas and dust introduced in the transfer process can seriously deteriorate interface characteristics, increase carrier scattering and a recombination center, cause uncontrollable strain and structural defects of interfaces due to interlayer Van der Waals force action and alignment errors, have poor process repeatability and large-scale capability, and are difficult to realize high-precision and high-consistency batch manufacturing. Meanwhile, the ion irradiation technology is widely applied to doping, defect engineering, surface etching and modification in the semiconductor industry as a mature material modification means. However, the application mode of ion irradiation in the prior art is mostly homogenization or patterning. Either uniformly changing the bulk properties of the material throughout the irradiated area (e.g., introducing uniform defects, effecting amorphization) or selectively removing areas of the material through a mask (etching). To date, no technology has been reported to utilize the intrinsic difference of interactions between ions and different elements of materials (such as different sputtering yields and scattering cross sections), take ion irradiation as a precise tool for component space reconstruction, actively engrave continuously-changing component distribution by carrying out selective and gradient element removal in the depth direction of a single uniform film, and utilize the component gradient as driving force to induce local phase change in situ inside the film, so as to finally realize one-step conversion from the single uniform film to the built-in heterojunction. Therefore, a new method which can build high-quality heterojunction in situ in single material, has simple process and strong controllability and is compatible with the prior art is developed, and the method becomes a technical bottleneck to be broken through in the fields of semiconductor materials and devices. Disclosure of Invention Aiming at the defects in the prior art, the invention discloses a compound thin film heterojunction, a preparation method and application thereof, and aims to solve the technical problems that the traditional heterojunction preparation process is complex and the interface is easy to pollute. In order to achieve the above purpose, the technical scheme adopted by the invention is to provide an in-situ preparation method of a compound film heterojunction, which comprises the following steps: S1, providing a substrate with an A xBy film, wherein an element A is a metal element, and an element B is a chalcogen element, an initial phase of the A xBy film is a first phase, and the numerical ratio of x to y is 0.1-10:1; S2, irradiating the A xBy film by using an ion beam, wherein the energy of the ion beam is different in sputtering yield of the element A and the element B, so th