Sputter Target

0040-31980 GAS BOX EC WXZ

0040-09095 Gas Box, Wcvd

 

In magnetron sputtering coating technology, the importance of sputtering targets is self-evident. As a key component, its material type, purity and surface condition have a direct and profound impact on the performance of the film. Careful selection of the right target is a necessary prerequisite for high-performance thin film fabrication.
I. Carefully select the appropriate target

1. Target selection according to application requirements
The choice of target material is not arbitrary, but closely revolves around the application requirements and performance requirements of the film. Among the rich and diverse target materials, metals, alloys, ceramics and compounds have their own characteristics and have different application scenarios.
1.1Metal targets
With good conductivity and reflectivity, metal targets occupy an important position in the preparation of conductive films and reflective films. For example, in the electronics industry, copper targets are often used to prepare conductive circuits, because the electronic structure of metals is relatively simple, and it is easy to form free electrons, so it has excellent conductivity. Silver targets are widely used in the production of reflective films, and their high reflectivity plays a key role in the field of optics, which can be used to make mirrors and optical reflectors.
1.2 Ceramic and compound targets
Ceramic and compound targets play a key role in the preparation of insulating and optical films. Ceramic targets such as alumina, silicon oxide, etc., have high insulation and good chemical stability, which can meet the strict requirements of electronic devices for insulation performance. In the field of optics, compound targets such as zinc oxide, titanium oxide, etc., can be used to prepare thin films with specific optical properties, such as anti-reflection coatings, anti-reflection coatings, etc. The lattice structure and electronic structure of these targets determine their unique performance in terms of optical and electrical properties.

2.Consider lattice structure, electronic structure, and chemical stability
Lattice structure, electronic structure, and chemical stability are key factors that must be considered when selecting target materials.
2.1The influence of lattice structure
The lattice structure determines the growth mode and crystallization quality of the film. When the lattice structure of the target is matched to the substrate material, the film is more easily formed by epitaxial growth, resulting in high-quality crystalline films. For example, in the semiconductor industry, silicon targets are often used to prepare epitaxial silicon films on silicon substrates to ensure good lattice matching between the film and the substrate and improve device performance.
2.2 The role of electronic structure
The electronic structure affects the electrical properties of the film. Different target materials have different electronic structures, thus exhibiting different conductivity types and conductive properties. Metal targets usually have free electrons and exhibit good electrical conductivity; However, the electronic structure of semiconductor targets is complex, and their conductivity can be controlled by doping.
2.3The importance of chemical stability
Chemical stability is an important indicator to measure whether the target material can maintain stable performance in different environments. For some films used in harsh environments, such as corrosion-resistant films, high-temperature resistant films, etc., it is necessary to select target materials with high chemical stability. For example, in the aerospace field, titanium alloy targets are often used to prepare high-temperature, corrosion-resistant films to protect the critical components of aircraft.
II,The Impact of Target Purity: A Trade-off Between Performance and Cost
1.The advantages of high-purity targets
The purity of the target material has a significant impact on the chemical composition and properties of the film. High-purity targets reduce the amount of impurities in the film, which in turn improves the chemical stability and electrical properties of the film.
In the electronics industry, the presence of impurities can lead to increased resistance of the conductive film, degrading the performance and reliability of the device. High-purity metal targets can be used to produce conductive films with low resistance to meet the needs of high-performance electronic devices. Similarly, in the semiconductor industry, the presence of impurities can affect the electrical and optical properties of thin films and even lead to device failure. High-purity semiconductor targets can be used to produce high-quality semiconductor films, improving the performance and stability of devices.
In addition, high-purity targets can improve the chemical stability of the film. The presence of impurities may cause the film to chemically react in a specific environment, reducing the life of the film. High-purity targets reduce the occurrence of this chemical reaction and extend the lifetime of the film.

2.A rational trade-off between purity and cost

However, too much purity can also lead to an increase in target costs. In practical applications, it is necessary to rationally weigh the relationship between the purity and cost of the target material under the premise of meeting the performance requirements of the film. For some applications with extremely high performance requirements, such as high-end electronic devices, semiconductor manufacturing, etc., high-purity targets may be required. Although the cost is high, the performance requirements for thin films in these fields are extremely stringent, and high-purity targets are the key to ensuring product quality. For some application fields with relatively low performance requirements, such as ordinary decorative films, protective films, etc., the purity requirements of the target can be appropriately reduced to reduce costs. In these areas, the performance requirements for the film are relatively relaxed, and the appropriate impurity content may not have a noticeable impact on the performance of the product in use.

III,The influence of the surface condition of the target: the key to ensuring the high quality of the film

1.The importance of cleanliness and flatness
The cleanliness and flatness of the target surface have a significant impact on the growth and performance of the film. Impurities and defects on the target surface can cause defects in the film, which in turn can affect the uniformity and adhesion of the film.
1.1The impact of cleanliness
The clean surface of the target ensures a stable and consistent sputtering process. If there are impurities on the surface of the target, such as oil, dust, etc., these impurities may be sputtered out during the sputtering process and mixed into the film, resulting in a decrease in the quality of the film. In addition, impurities may affect the energy and direction of the sputtered atoms, disrupt the growth process of the film, and affect the uniformity and crystallization quality of the film.
1.2The role of flatness
The flat surface of the target facilitates uniform growth of the film. If there is an uneven defect on the surface of the target, the deposition rate of the sputtered atoms will vary at different locations, resulting in an uneven thickness of the film. In addition, uneven target surfaces may affect the angle of incidence and energy distribution of sputtered atoms, resulting in differences in the properties of the film.

Strict cleaning and handling methods
To ensure the high quality of the film, the surface of the target needs to be rigorously cleaned and treated before sputtering.
2.1Cleaning Method
Common cleaning methods include mechanical, chemical, and plasma cleaning. Mechanical cleaning can remove large particles of impurities and dirt on the surface of the target, but some small impurities may not be completely removed. Chemical cleaning uses the dissolution of chemical reagents to remove impurities such as oil stains and oxides on the surface of the target material. Plasma cleaning uses the active action of plasma to remove organic pollutants and adsorbents on the surface of the target, and at the same time, it can also activate the surface of the target to improve the adhesion of the film.

2.2 Surface treatment
After cleaning, the surface of the target can also be treated, such as polishing, coating, etc. Polishing can make the surface of the target smoother and smoother, and improve the uniformity of the film. The coating forms a protective film on the surface of the target to prevent oxidation or contamination during sputtering, and also improves the stability and consistency of the sputtering process.