The purity of high-quality titanium target blocks:

Purity is one of the main performance indicators of the Molybdenum Sputtering Target, because the purity of the target has a great influence on the performance of the thin film. However, in practical applications, the requirements for the purity of the target are not the same. For example, with the rapid development of the microelectronics industry, the size of silicon wafers has been developed from 6", 8" to 12", while the wiring width has been reduced from 0.5um to 0.25um, 0.18um, or even 0.13um, and the previous target purity was 99.995%. It can meet the process requirements of 0.35um IC, while the preparation of 0.18um lines requires 99.999% or even 99.9999% for the purity of the target.

Impurities in target solids and oxygen and moisture in pores are the main sources of contamination for deposited films. Targets of different uses have different requirements for different impurity contents. For example, pure aluminum and aluminum alloy targets used in the semiconductor industry have special requirements for alkali metal content and radioactive element content.

In order to reduce the pores in the target solid and improve the performance of the sputtered film, the target is usually required to have a higher density. The density of the target affects not only the sputtering rate, but also the electrical and optical properties of the film. The higher the target density, the better the performance of the film. In addition, increasing the density and strength of the target allows the target to better withstand the thermal stress during sputtering. Density is also one of the key performance indicators of the target.

 Usually the target material is of polycrystalline structure, and the grain size can be in the order of micrometers to millimeters. For the same target, the sputtering rate of the target with fine grains is faster than the sputtering rate of the target with coarse grains; and the thickness distribution of the thin film deposited by sputtering of the target with smaller grain size difference (uniform distribution) is more uniform.