Two-step hot isostatic pressing diffusion welding method for tungsten target assembly

Abstract

The invention discloses a two-step hot isostatic pressing diffusion welding method for a tungsten target assembly, and belongs to the technical field of magnetron sputtering target manufacturing. According to the welding method, hot isostatic pressing diffusion welding is carried out on a tungsten target blank and an Al intermediate layer, then secondary hot isostatic pressing diffusion welding iscarried out on the tungsten target blank and a copper back plate, finally, the tungsten target material assembly is obtained, and the welding strength of the tungsten target blank-Al intermediate layer welding face of the tungsten target material assembly is larger than or equal to 125 MPa, the welding strength of the Al intermediate layer-copper back plate welding face is larger than or equal to65 MPa, the welding-on rate of the two welding faces is larger than 99.5%, the overall deformation degree of the target material after welding is small, the target material is suitable for a high-power sputtering machine table, and it is guaranteed that desoldering and target falling are avoided in the sputtering process.

Description

technical field [0001] The invention belongs to the technical field of magnetron sputtering target manufacturing, in particular to a two-step hot isostatic pressure diffusion welding method for tungsten target components. Background technique [0002] High-purity tungsten targets are widely used in the manufacture of advanced memory chips, and are key materials for the manufacture of advanced memory chips such as 3D NAND flash and DRAM. In the gate metal stack layer, WN / W is formed to maintain a low gate stack resistivity, and WN acts as a key barrier layer to prevent the reaction between W and polysilicon. At present, the tungsten film layer in advanced memory chips is mainly deposited by magnetron sputtering tungsten target. During the sputtering coating process, high-speed particles bombard and etch the surface of the target. If the heat cannot be effectively conducted, the surface temperature of the target will drop. It rises sharply, so it needs to solder a backplate o...

AI Technical Summary

Problems solved by technology

However, due to the huge difference in physical properties between the W target blank, the copper back plate and the Al intermediate layer, it is impossible to ensure that the W target blank- Al interlayer and Al interlayer-copper backplane have high welding strength on both welding surfaces

Usually the welding strength of one welding surface is higher, and the welding strength of the other welding surface is lower

Images