The Role of Sputtering Targets in Vacuum Sputtering

Introduction to Vacuum Sputtering

Vacuum sputtering is a thin-film technology to deposit thin films and coatings by creating a sub-atmospheric pressure environment and an atomic or molecular condensable vapor source. The basic principle is to make argon (Ar) ions hit the surface of the sputtering target through glow discharge in a vacuum, so that the target atoms overflow and deposit on the substrate to form a thin film.

Most general metal materials use DC sputtering, while non-conductive ceramic materials use RF sputtering. The new sputtering coating equipment uses powerful magnets to accelerate the ionization of argon gas around the target material in a spiral shape, thereby increasing the probability of collision between the target material and argon ions, thereby increasing the sputtering rate.

Characteristics of Sputtering Coating Process

(1) It has a wide range of applications, and can make metal, alloy or insulator materials into thin films.

(2) Under proper setting conditions, multi-component targets can be made into thin films with the same composition.

(3) A mixture or compound of the target substance and gas molecules can be produced by adding oxygen or another reactive gas to the discharge atmosphere.

(4) The target input current and sputtering time are controllable, which is conducive to obtaining high-precision film thickness.

(5) Sputtering coating is more conducive to producing large-area uniform films than other processes.

(6) The sputtered particles are not affected by gravity, and the positions of the target and the substrate can be freely arranged.

(7) The bonding strength between the substrate and the film is more than 10 times that of the general evaporated film, and because the sputtering particles have high energy, the surface of the film is continuously diffused to obtain a hard and dense film. At the same time, high energy allows the substrate to obtain a crystalline film at a lower temperature.

(8) The nucleation density is high at the initial stage of film formation, and an extremely thin continuous film of 10 nm or less can be produced.

(9) The target has a long service life and can be continuously produced for a long time.

(10) The target can be made into various shapes, and with the special design of the machine, it can be controlled better and has the highest efficiency.

How Target Purity Affects Thin Film Quality

Many factors can affect the quality of a thin film, of which the purity of the sputtering target has the greatest impact. If the target material is not pure enough, the impurity particles in the target material will adhere to the surface of the substrate during the sputtering process, causing the film layer in some positions to be weak and peel off. Simply put, the higher the purity of the target material, the better the performance of the film.

For targets with poor thermal conductivity, such as silicon aluminum sputtering targets, the heat transfer is often hindered by impurities in the target. There is a difference between the cooling water temperature used in production and the actual water temperature of the coating line, which leads to cracking of the target during use. Generally speaking, slight cracks will not have a great impact on coating production. However, when the target has obvious cracks, the charge is easily concentrated on the edge of the crack, resulting in abnormal discharge on the surface of the target. Discharging will lead to slag falling, abnormal film formation, and increased product scrapping. Therefore, in the process of target preparation and purity control, it is also necessary to control the preparation process conditions.

Stanford Advanced Materials (SAM) is a global sputtering targets manufacturer which supplies high-quality and consistent products to meet our customers’ R&D and production needs. Please visit for more information.


Impact of Thin Film Technology on The Crystalline Silicon Industry

Judging from the current development of photovoltaic technology, thin films, especially CIGS thin films, will gradually become the mainstream of solar power generation.

Thin-Film Solar Cell

Thin-film photovoltaic cells, also known as solar cells, are devices that use the photovoltaic effect to convert light energy into electrical energy. They are considered novel photovoltaic devices that can alleviate the energy crisis.

Thin-film solar cells can be fabricated on substrates using materials such as ceramics, graphite, and metal sheets. These raw materials, while relatively cheap, work very well. They can make thin films with a thickness of only a few micrometers, and the current conversion efficiency can reach 13%.

In addition to planar, thin-film solar cells can also be made into non-planar structures because of their flexibility. Therefore, they have a wide range of applications and can be combined with or become part of buildings.


The aforementioned CIGS is mainly composed of Cu (copper), In (indium), Ga (gallium), and Se (selenium), and the complete chemical formula is CuInxGa(1-x)Se2. This material has many advantages, including strong light absorption ability, good power generation stability, high conversion rate, long daytime power generation time, low production cost, short energy recovery cycle, etc.

Polycrystalline Silicon Solar Cells
Ogunshile, Emmanuel. (2017). An Investigation into the Use of Hybrid Solar Power and Cloud Service Solutions for 24/7 Computing. 743-754. 10.5220/0006380007430754.

CIGS VS. Silicon

Why thin film technology will beat traditional crystalline silicon products? Comparing the two, you will find the following results.

  • The absolute power generation of the thin film is higher, and the average power generation is about 8-10% higher than that of crystalline silicon (depending on the location and climate of the power station).
  • The decay rate of CIGS thin film power generation is controllable, which means that the occurrence of power generation decay can be controlled by adopting effective technical means. The practice has proved that during the operation of the CIGS thin-film station, the power generation does not decrease, but increases slightly.

For the comparison between CIGS thin film and Silicon materials, you can refer to this article Silicon Thin-Film VS. CIGS Thin-Film for Solar Panels.


Although the crystalline silicon industry has matured and the conversion efficiency of monocrystalline silicon has also been improved, technical shortcomings restrict the sustainable development of the crystalline silicon industry. What’s worse is that its industrial chain is long, the cost is difficult to control, and crystalline silicon products are not competitive. From this point of view, the development of thin film technology, especially CIGS thin film, will get better and better.

Stanford Advanced Materials (SAM) is a global sputtering target manufacturer which supplies high-quality and consistent products to meet our customers’ R&D and production needs. We provide high-purity CIGS materials and we insure you will be satisfied with our products. Please visit our website for more information.