Table of contents:
The specifications of hafnium targets are generally round targets or square targets
Technical requirements for target materials
Hafnium target is a product formed by a series of processing (vacuum electron beam secondary melting, forging, machining, rolling, lathing and polishing, etc.) on the basis of crystallized hafnium (high purity hafnium). According to the different zirconium content, our company divides hafnium targets into first-grade hafnium targets (Hf+Zr>99.95%, Zr<0.5%) and second-grade hafnium targets (Hf+Zr>99.95%, Zr<1%). The finished hafnium target has very high requirements for purity, grain size, surface roughness, flatness and tolerance range.
The common specifications of round targets are：φ355.6*6.35mmT, φ304.8*6.35mmT, φ203.2*6.35mmT, φ152.4*6.35mmT, φ300*8mm, etc. Common specifications of square targets are: 320*100*8mm, 190*76*8mm, 200*200*6mm, 200*200*10mm, etc.
Hafnium targets are mainly used for optical coating and semiconductor coating. Currently, optical coating is the most widely used, which can increase the resolution of optical lenses.
Purity: The higher the purity of the target material, the better the performance of the sputtered film. However, the purity of targets used in general industrial applications is not demanding, while the purity requirements of targets used in semiconductors, display devices and other fields are very strict. The purity requirements of targets used in magnetic films are generally above 99.9%.
Impurity content: The target material is used as the cathode source in sputtering. Impurities in the solid and O2 and H2O in the pores are the main sources of contamination for deposited films. The lower the total impurity content, the higher the purity.
Density: The density of the target material not only affects the deposition rate during sputtering, the density of the sputtered film ions and the discharge phenomenon, but also affects the electrical and optical properties of the sputtered film. The denser the target material, the lower the density of the sputtered film particles, the weaker the discharge phenomenon, and the better the film.
Composition and structural uniformity: Composition and structural uniformity are one of the important indicators for evaluating the quality of the target material.
Connection between the target material and the chassis: Most targets must be connected to the oxygen-free copper (or other materials such as A1) chassis before sputtering, so that the thermal and electrical conductivity of the target material and the chassis are good during the sputtering process.
