The Evolution Of Microstructure And Texture Of High Purity Copper-manganese Alloy Sputter Target During Recrystallization

With the development of ultra-scale integrated circuits, copper replaces aluminum as the metallization materials has become an inevitable trend because of the nano-size wiring width。In a great many of copper alloys, researchers pay much attention to high purity Cu-Mn alloy due to its self-deformed barrier layer. The microstructure and texture are the key factors to affect the target’s sputtering performance,so it is pretty important to understand the evolution rules about the microstructure and texture to improve the target’s quality. Therefore, In order to improve the sputtering performance of sputtering target and ensure the quality of the as-deposited film, in this paper, the microstructure and texture of unidirectional-rolled and cross-rolled samples with different deformation after recrystallization of Cu-Mn alloy plate was characterized by Optical Microscope(OM), Scanning Electron Microscope(SEM), X-ray Diffraction(XRD) and Electron Back-scatted Diffraction(EBSD). The main results and conclusions can be drawn:(1) In the isothermal annealing experiment at 450℃ for the unidirectional rolling, the 50% deformation sample completed the recrystallization at 450℃ for 60 min, while the 77% and 95% deformed sample finished the recrystallization at 450℃ for 30 min. Among the all annealed samples, 50% annealed samples obtained the biggest average grain size, while the average grain size of 95% annealed samples was the least.(2) In the isothermal annealing experiment at 450℃,the fraction of annealing twins in the 50% unidirectional-rolled samples was the highest, while the 95% unidirectional-rolled samples is the least. For the cross-rolled 95% samples, its annealing twins’ fraction was less than the unidirectional-rolled 95% after recrystallization.(3) In the isothermal annealing experiment at 450℃ for the unidirectional-rolled samples, there was still a strong Brass texture in the 50% deformation and 77% deformation samples after recrystallization. For the 95% deformed samples, the main recrystallization texture were the cube-texture and RD-rotated cube texture. Except that, the cube texture and RD-rotated cube texture showed up at the earliest for all isothermal annealed samples.(4) In the isochronal annealing experiment for the high deformation, 95% unidirectional-rolled samples completed the recrystallization mainly at 400℃ for 60 min,and cube texture, RD-rotated cube texture’s orientation density enhanced, the brass-R1 texture came to show up; for the 95% cross-rolled sample, it achieved recrystallization at 450℃ for 60 min. After 400℃ annealing, a lot of residual deformed microstructure stayed in it. So it can illustrate the recrystallization rate in the unidirectional rolling is slower than the unidirectional rolling. A very strong Brass texture stayed in the 400℃annealed sample, and the cube texture and RD-rotated texture came to show up,their densities increased at 450℃.(5) In the isochronal annealing experiment for the 95% deformed samples by unidirectional rolling and cross rolling, the orientation density of α-fibre and β-fibre decreased with the annealing temperature increase as a whole. However, for the cross-rolled 95% sample, its orientation density of α-fibre and β-fibre came to increase after 600℃ annealing, the brass texture increased obviously.