In all application industries, the semiconductor industry has the most stringent quality requirements for sputtering films on target materials. Now 12-inch (3 0 0 Nvxue) Silicon wafers have been made. The width of the interconnects is decreasing. The requirements of wafer manufacturers for target materials are large size, high purity, low segregation and fine grain, which requires a better microstructure of the target material. The diameter and uniformity of the crystalline particles of the target material have been considered as the key factors affecting the deposition rate of the films.
In addition, the purity of the film is highly related to the purity of the target, and the $number. $number% (4 N5) purity of the copper target, may be able to meet the needs of semiconductor manufacturers 0.3 5pm process, but can not meet today's 0.2 5um process requirements, while the 0.18um Art even 0.13m process, the required target purity will be required to achieve 5 or even 6N. Copper compared with aluminum, copper has a higher resistance to the transfer of power and lower resistivity, can be satisfied! Conductor process in 0. Sub-micron wiring below 25um but with rice the other problem: the adhesion strength of copper and organic medium material is low. And it is easy to react, causing the copper interconnects in the chip to be corroded and break open during use. To solve these problems, a barrier layer between the copper and the dielectric layer is required. The barrier layer material generally uses the high melting point, the high resistivity metal and its compound, therefore requests the barrier layer thickness is less than 50n m, and the copper and the dielectric material adhesion performance is good. The barrier layer materials of copper interconnection and aluminum interconnection are different. New target materials need to be developed. The target material of the barrier layer of CU interconnection includes t A, W, t a s I, WS I and so on. But T-A and W are refractory metals. Production is relatively difficult, is now studying molybdenum, chromium and other gold as an alternative material.