阅读说明：本技术 一种基于气体团簇离子束溅射的薄膜沉积方法 (Film deposition method based on gas cluster ion beam sputtering ) 是由 瓦西里·帕里诺维奇 曾晓梅 亚历山大·托斯托古佐夫 付德君 刘传胜 于 2019-11-12 设计创作，主要内容包括：本发明提供了一种基于气体团簇离子束溅射的薄膜沉积方法,将气体团簇离子束的产生过程和靶材的溅射过程分开,无气体杂质的污染,溅射出的靶材材料直接沉积为薄膜,提高了薄膜的纯度；气体团簇离子束的能量介于3-20keV,使得靶材材料溅射率高,薄膜沉积率高,使用目标薄膜材料制成靶材,且气体团簇离子束中的单原子能量很低,不至于熔化靶材,尤其适用于制备熔点低于200℃的低熔点、多元素组分的固体电解质薄膜；环绕靶材设置2个以上的衬底,一次性沉积2个以上的薄膜,耗时短,薄膜沉积效率高；制膜条件严格可控,重复性好,形成的薄膜纯度高、均匀可控,厚度介于100-1000nm。(The invention provides a film deposition method based on gas cluster ion beam sputtering, which separates the generation process of gas cluster ion beams from the sputtering process of a target material, has no pollution of gas impurities, directly deposits the sputtered target material into a film, and improves the purity of the film; the energy of the gas cluster ion beam is between 3 and 20keV, so that the sputtering rate of the target material is high, the deposition rate of the film is high, the target material is made of the target film material, the energy of single atoms in the gas cluster ion beam is very low, the target material cannot be melted, and the method is particularly suitable for preparing a low-melting-point multi-element solid electrolyte film with a melting point lower than 200 ℃; more than 2 substrates are arranged around the target material, more than 2 films are deposited at one time, the time consumption is short, and the film deposition efficiency is high; the film preparation conditions are strictly controllable, the repeatability is good, the purity of the formed film is high, the film is uniform and controllable, and the thickness is between 100 and 1000 nm.)

1. A film deposition method based on gas cluster ion beam sputtering is characterized by comprising the following steps:

(1) gas cluster ion beam generation process: generating a gas cluster ion beam with a size of 3000-5000atoms/cluster and an energy of 3-20keV in the gas cluster ion source, wherein the vacuum degree of the gas cluster ion beam generation region is maintained at 10^{- 1}Pa；

(2) Sputtering process of the target: the target material is made of the target film material, the gas cluster ion beam bombards the surface of the target material to cause the surface of the target material to burst, and the target material is sputtered out in a particle form and deposited on the substrate to form the film; the vacuum degree of the target sputtering area is less than 10^-4Pa。

2. The method of claim 1, wherein: the gas cluster ion beam in the step (1) is formed by ultrasonic adiabatic expansion of a conical nozzle.

3. The method of claim 1, wherein: the cluster diameter of the gas cluster ion beam in the step (1) is 1-3 nm.

4. The method of claim 1, wherein: the gas cluster ion beam in the step (1) is Ar, Xe, H₂、O₂、N₂Or CO₂One or more than two of the gases.

5. The method of claim 1, wherein: the energy of the single atom in the gas cluster ion beam is 0.5-10eV, and under the same speed condition, the momentum of the gas cluster ion beam in the step (1) is 3000-5000 times of the momentum of the traditional single atom ion.

6. The method of claim 1, wherein: the sputtered target material in the step (2) is composed of nano-particles with the diameter of 1nm-30 nm.

7. The method of claim 1, wherein: and (3) bombarding the surface of the target by the gas cluster ion beam, wherein the angular distribution of the target material sputtered from the surface of the target follows a sub-cosine curve law, and the sputtering process has cylindrical symmetry.

8. The sputtering process of the target material according to claim 7, having cylindrical symmetry, characterized in that: more than 2 substrates are arranged around the target.

9. The method of claim 1, wherein: the thickness of the thin film in the step (2) is between 100 and 1000 nm.

Technical Field

The invention relates to a film deposition method based on gas cluster ion beam sputtering, and belongs to the field of film deposition.

Background

The solid electrolyte has ion conductivity due to its rapid ion migration channel, which attracts great attention of people and becomes an important research field of material science. Currently, the developed ion conductor has silver conductive crystal MAg₄I₅(where M may be K, Rb and NH)₄) Sodium-based B-alumina and copper-based compound Rb₄Cu₁₆I₇Cl₁₃. These ionic conductors are widely used in solid state batteries, capacitors, power switches, memory devices, and ion beam generation. CsAg₄Br₃I₂Because of its excellent ion conductivity, it is a single crystal solid electrolyte with great potential. This material can be used as a raw material for producing silver ions in an ion source, constituting a solid electrolyte ion source. The solid electrolyte ion source is a novel ion emitting device, has the advantages of small volume, long service life, high efficiency, low power consumption and the like, and can be applied to an electric propulsion system of an outer space aircraft to promote the operation or attitude adjustment of a small spacecraft. The best configuration of the solid electrolyte for generating silver ions is to deposit a thin film on a silver substrate. However, many solid electrolyte materials tend to have a low melting temperature (below 200 ℃) and a complex chemical composition (over 3 elements). Therefore, the deposition of a thin film of a solid electrolyte with a complicated composition at a relatively low temperature is an important technical process of an ion source.

Vapor deposition methods for thin films mainly include two main categories — physical vapor deposition PVD and chemical vapor deposition CVD. Compared with CVD, PVD has the advantages of environmental protection, no pollution, less material consumption, uniform and compact film formation, strong binding force with the matrix, and the like. PVD also includes evaporation, pulsed laser deposition, cathodic arc ion plating, magnetron sputtering (dc sputtering, magnetron sputtering) and other methods, generally speaking, since evaporation coating and cathodic arc ion plating require heating, the initial material is often decomposed to form a two-phase film, which reduces the film quality. The working temperature of the magnetron sputtering is slightly lower, so that the chemical components are easy to control when the multi-element alloy film is deposited, and the adhesion between the deposited layer and the substrate is better. However, the sputtering coating method is to place the target and the substrate in a glow discharge environment at the same time, which affects the purity of the film to some extent. Therefore, it is difficult to form a multi-element thin solid electrolyte film having a low melting point by the conventional thin film deposition method.

Disclosure of Invention

The present invention aims to solve the disadvantages of the prior art and to provide a method for deposition of a film based on gas cluster ion beam sputtering for deposition of a low melting point (below 200 ℃) multi-element solid electrolyte film.

The technical scheme adopted for achieving the purpose of the invention is as follows: the film deposition method based on gas cluster ion beam sputtering specifically comprises the following steps:

(1) gas cluster ion beam generation process: generating a gas cluster ion beam with a size of 3000-5000atoms/cluster and an energy of 3-20keV in the gas cluster ion source, wherein the vacuum degree of the gas cluster ion beam generation region is maintained at 10^-1Pa；

(2) Sputtering process of the target: the target material is made of the target film material, the gas cluster ion beam bombards the surface of the target material to cause the surface of the target material to burst, and the target material is sputtered out in a particle form and deposited on the substrate to form the film; the vacuum degree of the target sputtering area is less than 10^-4Pa。

The gas cluster ion beam in the step (1) is formed by ultrasonic adiabatic expansion of a conical nozzle.

The cluster diameter of the gas cluster ion beam in the step (1) is 1-3 nm.

The gas cluster ion beam in the step (1) is Ar, Xe, H₂、O₂、N₂Or CO₂One or more than two of the gases.

The energy of the single atom in the gas cluster ion beam is 0.5-10eV, and under the same speed condition, the momentum of the gas cluster ion beam in the step (1) is 3000-5000 times of the momentum of the traditional single atom ion.

The sputtered target material in the step (2) is composed of nano-particles with the diameter of 1nm-30 nm.

And (3) bombarding the surface of the target by the gas cluster ion beam, wherein the angular distribution of the target material sputtered from the surface of the target follows a sub-cosine curve law, and the sputtering process has cylindrical symmetry.

More than 2 substrates are arranged around the target.

The thickness of the thin film in the step (2) is between 100 and 1000 nm.

According to the technical scheme, the film deposition method based on gas cluster ion beam sputtering separates the generation process of the gas cluster ion beam from the sputtering process of the target, and has no pollution of gas impurities, and sputtered target materials are directly deposited into a film without collision, so that the purity of the film is improved; the target material is made of the target film material, and under the condition of the same speed, the momentum of the gas cluster ion beam is 3000-5000 times that of the traditional monatomic ion, so that the sputtering rate of the target material is high; the energy of single atom in the gas cluster ion beam is 0.5-10eV, which can not decompose and melt the target material, especially suitable for preparing solid electrolyte film with low melting point and multi-element component, the melting point of which is lower than 200 ℃; no plasma is generated near the substrate, so that the temperature rise of the substrate and the bombardment damage of ions and electrons cannot be caused; more than 2 substrates are arranged around the target, more than 2 films are deposited at one time, the time consumption is short, and the film deposition efficiency is high.

In conclusion, the technical scheme of the invention has the beneficial effects that:

(1) the generation process of the gas cluster ion beam is separated from the sputtering process of the target material, so that the pollution of gas impurities is avoided, and the purity of the film is easily improved;

(2) compared with the traditional monatomic ions (microscopic particles), the momentum of the gas cluster ions (mesoscopic particles) under the same speed condition is 3000-5000 times that of the monatomic ions, the sputtering rate is high, and the film deposition efficiency is high;

(3) the sputtering rate of the gas cluster ion beam is high, high beam current is not needed in the experimental process, the heating of the surface of the target material is reduced, the target material is not melted, and therefore the method can be applied to the deposition of the low-melting-point film;

(4) the energy of single atoms in the gas cluster ion beam is 0.5-10eV, so that the target material cannot be decomposed or melted, the sputtering target material component is ensured to be unchanged, the film component is unchanged, and the film quality is good;

(5) no plasma is generated near the substrate, so that the temperature rise of the substrate and the bombardment damage of ions and electrons cannot be caused;

(6) the film making conditions are strictly controllable, the repeatability is good, and sputtered target materials can be directly deposited into a film without collision;

(7) the angular distribution of the sputtered target material follows a sub-cosine curve law, the sputtering process has cylindrical symmetry, so that a plurality of substrates can be placed around the target material to deposit a plurality of films at one time, and the time consumption is short and the efficiency is high.

(8) The material has wide application range, including various powder, medium material and metal, and is suitable for various film materials, especially for solid electrolyte film with low melting point below 200 deg.c and multiple elements.

Drawings

Fig. 1 is a schematic view of the working principle of the thin film deposition method based on gas cluster ion beam sputtering.

In the figure: 1. gas cluster ion beam, 2 target, 3 target material, 4 deposited film, 5 substrate.

Detailed Description

The invention is further explained by the figures and the examples.

Fig. 1 is a schematic view of the working principle of the thin film deposition method based on gas cluster ion beam sputtering. The gas cluster ion beam 1 is formed by ultrasonic adiabatic expansion of a conical nozzle, the cluster size of the gas cluster ion beam is 3000-5000atoms/cluster, the diameter is 1-3nm, and the vacuum degree of a gas cluster ion beam generation area is kept at 10^-1Pa. The gas-cluster ion beam is ionized by electron impact after expanding from the nozzle and accelerated to an energy of 3-20keV by the electric field. The target 2 is made of a target film material, the generation of the gas cluster ion beam is separated from the sputtering process of the target, and the vacuum degree of the sputtering area is maintained below 10^-4Pa range. When the gas cluster ion beam bombards with a certain energyWhen the target material is used, the kinetic energy of the target material is absorbed by the target material in the surface layer and is converted into heat energy. Because the sputtering rate of the gas cluster ion beam is high, high beam current is not needed in the experimental process, the heating of the surface of the target material is reduced, and the target material is not melted. Due to the short impact time (a few ps), the energy density of the impact zone is high, resulting in a rapid rise in the impact zone temperature and a burst. After the target surface is burst, a hemispherical crater with the diameter of 10nm is formed in the impact area. The large size of the crater means that a large amount of ejected material is generated, which increases the efficiency of the thin film deposition.

The original target material 3 in the crater is ejected from the center of the target and is radiated and spread in all directions. The sputtered target material mainly consists of nano-sized nanoparticles with a diameter of 1nm-30nm, and the size of the sputtered target material can be changed by adjusting gas cluster parameters (size, energy and dosage). The transverse sputtering effect is a special effect generated when the target is bombarded by the gas cluster ion beam, and due to the effect, the angular distribution of the sputtered target particles follows the cosine law, that is, if the gas cluster ion beam bombards the target vertically, most sputtered particles of the target leave the collision area and exit parallel to the surface of the target in all directions, and finally deposit on the substrate 5 to form the film 4. To improve the film deposition efficiency, the substrate 5 is placed near the target edge. Since the sputtering process has cylindrical symmetry, multiple substrates can be placed simultaneously around the target. The obtained thin film 4 has high purity, uniformity and controllability, and the thickness can be between 100 and 1000 nm. The invention is suitable for forming various films, in particular to a low-melting-point multi-component solid electrolyte film with the melting point lower than 200 ℃.