The hot isostatic pressure diffusion welding method for tantalum target and aluminum backplane includes: placing tantalum target and aluminum backplane into vacuum envelope; The vacuum envelope is vacuumed; The vacuum package is put into a hot isostatic pressure furnace, and the temperature is first raised and the pressure is then kept warm and the pressure is maintained. The vacuum envelope is cooled by depressurization; Remove the vacuum envelope and take out the target combination formed by welding the tantalum target and the aluminum backplane. The welding strength of the tantalum target assembly obtained by the hot isostatic pressure diffusion welding method of the tantalum target and aluminum backplane provided by the invention can reach up to 150Mpa, and the yield can reach more than 98%. The tantalum target assembly formed by the method of the invention has the advantages of high bonding tightness, strong heat resistance to deformation, and the like.
In the semiconductor industry, the target assembly is composed of a target that conforms to the sputtering performance and a backplane that can be combined with the target and has a certain strength. The backplane can play a supporting role in the target assembly to the sputtering base, and has the effect of conducting heat. In the process of sputtering, the target assembly is in a harsh working environment. For example, the target assembly is located at a high ambient temperature, such as 300 ° C to 600 ° C; In addition, one side of the target assembly is strongly cooled by cooling water, while the other side is in a high vacuum environment of 10-9Pa, resulting in a huge pressure difference on the relative two sides of the target assembly; In addition, the target component is in a high voltage electric and magnetic field, and is bombarded by various particles. In such a harsh environment, if the binding strength between the target and the backplane in the target assembly is poor, it will cause the target assembly to deform and crack under hot conditions, and even make the target and the original combined backplane detached, and then can not get a uniform sputtering film, and may also cause damage to the sputtering base.
When the physical properties of the target and the backplane are close to each other, conventional welding processes such as fusion welding and brazing can be used to weld the target and the backplane together to form the target assembly; When the physical properties of the target and the backplane are very different, diffusion welding can be used to weld the target and the backplane together to form the target assembly. The so-called diffusion welding refers to the welding method that tightly fits the welds and maintains them under a certain temperature and pressure for a period of time, so that the atoms between the contact surfaces of the two welds diffuse each other to form a connection. Compared with the conventional welding method, diffusion welding has the advantages of high bonding tightness and strong resistance to deformation under heat.
