How to make sputtering target?

Raw material powder–powder smelting–powder mixing–pressing molding–atmosphere sintering–plastic processing–heat treatment–ultrasonic flaw detection–water cutting–machining–metallization–binding–ultrasonic testing–ultrasonic cleaning–inspection–shipping.

Among them, the specific meanings of the main processes are as follows:

Powder smelting: the raw material powder is subjected to preliminary atmosphere sintering to control the gas content in the raw material powder.

Powder mixing: the target material has a unique formula, and the content of each component needs to be accurately controlled, and the impurity content needs to be strictly limited. In the process of powder metallurgy, it is necessary to fully mix the elements evenly, and the particle size distribution is uniform to prevent pollution, and a mixed composite powder needs to be prepared by special process means.

Pressing molding: the target material prepared by powder metallurgy process needs to pre-press the powder material to make it a medium-density green body. Its density uniformity and internal defects affect the yield of high-temperature sintering in the later stage.

Atmosphere sintering: The pre-pressed green body needs to undergo one or more high-temperature sintering. Different sintering temperature curves are selected according to different materials, and different sintering environments, such as sintering atmosphere and sintering pressure, are selected to prepare high-density target blanks.

Plastic processing: The metal billet needs to undergo a large plastic deformation to obtain sufficient length, width and thickness dimensions, and to allow the internal grains to undergo sufficient tensile deformation, thereby generating enough dislocations inside.  Heat treatment: After the metal billet undergoes a large plastic deformation, the heat treatment process is selected according to the characteristics of different materials, so that the metal material can be recrystallized and the internal stress of the material can be removed.

Ultrasonic flaw detection: After the target blank is processed, ultrasonic waves need to be used to check whether there are defects inside the material. After the target blank is bonded to the back plate, a water-immersion ultrasonic scanner needs to be used to detect the bonding layer to check whether the bonding area meets the standard.

Mechanical processing: The target blank needs to be processed by precise mechanical forming. The back plate used in combination with the target blank needs to have extremely high dimensional accuracy and mechanical strength due to its precise coordination with the coating equipment and high-pressure water cooling. The processing difficulty is relatively high, especially for the back plate with an internal circulation water channel. Due to the particularity of the material, the closed welding of the water channel is very difficult and requires a special welding process.

Metallization: Before the target blank and the back plate are bound, in order to enhance the metal wetting properties of the target material and the target material and the solder, the welding surface needs to be pre-treated so that a transition layer is plated on the surface.

Bonding: Most target materials cannot be directly installed for coating due to the physical or chemical properties of the material. Metal solder is needed to weld the target blank and the back plate together, and the effective bonding rate of the surface needs to reach a large area welding greater than 95%. The whole process needs to be carried out under high temperature and high pressure.