“…The above changes confirm that the insoluble elements dissolve in copper alloys in the solid-solution state, which has a positive effect on the stability. Similar results have been reported for a copper alloy film [28][29][30].…”
Section: Resultssupporting
confidence: 90%
“…The above changes confirm that the insoluble elements dissolve in copper alloys in the solid-solution state, which has a positive effect on the stability. Similar results have been reported for a copper alloy film [28–30]. Figure 9 Conductivity, hardness and melting point as Cu content for Cu x [Ni 3 Mo] ( x = 1, 2, 3, 4, 5, 7, 9 and 12) alloys after solution treatment (1238 K/6 h) and aging (923 K/4 h).…”
Mo could be dissolved into Cu to increase its high-temperature stability via a Ni intermediate. The microstructure evolution and strengthening mechanism of Cu x[Ni3Mo] ( x = 1, 2, 3, 4, 5, 7, 9, 12) alloys were investigated. The results show that composition significantly affects strengthening mechanisms of the alloys. For x = 1 and 2, The strengthening mechanisms of the alloys are mainly precipitation strengthening derived from Ni2Mo and Ni4Mo nanophases, both of which coexist and coherently grow on the face-centered cubic matrix. For x = 3–5, the nanophases gradually decrease and spinodal decomposition structure increases, which transforms the strengthening mechanism to spinodal decomposition strengthening. For x = 7–12, spinodal decomposition structure and precipitates reduce significantly, the solution strengthening dominates namely.
“…The above changes confirm that the insoluble elements dissolve in copper alloys in the solid-solution state, which has a positive effect on the stability. Similar results have been reported for a copper alloy film [28][29][30].…”
Section: Resultssupporting
confidence: 90%
“…The above changes confirm that the insoluble elements dissolve in copper alloys in the solid-solution state, which has a positive effect on the stability. Similar results have been reported for a copper alloy film [28–30]. Figure 9 Conductivity, hardness and melting point as Cu content for Cu x [Ni 3 Mo] ( x = 1, 2, 3, 4, 5, 7, 9 and 12) alloys after solution treatment (1238 K/6 h) and aging (923 K/4 h).…”
Mo could be dissolved into Cu to increase its high-temperature stability via a Ni intermediate. The microstructure evolution and strengthening mechanism of Cu x[Ni3Mo] ( x = 1, 2, 3, 4, 5, 7, 9, 12) alloys were investigated. The results show that composition significantly affects strengthening mechanisms of the alloys. For x = 1 and 2, The strengthening mechanisms of the alloys are mainly precipitation strengthening derived from Ni2Mo and Ni4Mo nanophases, both of which coexist and coherently grow on the face-centered cubic matrix. For x = 3–5, the nanophases gradually decrease and spinodal decomposition structure increases, which transforms the strengthening mechanism to spinodal decomposition strengthening. For x = 7–12, spinodal decomposition structure and precipitates reduce significantly, the solution strengthening dominates namely.
“…Within the range of this ratio, the strong interaction between the alloy elements can inhibit the diffusion of Zr in Cu. In the literature [27], as an appropriate amount of Ge and Fe is added in the Cu film, the stability of the Cu film can be improved and the diffusion of Ge in Cu can also be inhibited, which is similar to the results herein.…”
Low resistivity, phase stability and nonreactivity with surrounding dielectrics are the key to the application of Cu to ultra-large-scale integrated circuits. Here, a stable solid solution cluster model was introduced to design the composition of barrierless Cu–Ni–Zr (or Fe) seed layers. The third elements Fe and Zr were dissolved into Cu via a second element Ni, which is soluble in both Cu and Zr (or Fe). The films were prepared by magnetron sputtering on the single-crystal p-Si (1 0 0) wafers. Since the diffusion characteristics of the alloying elements are different, the effects of the strong interaction between Ni and Zr (or Fe) on the film’s stability and resistivity were studied. The results showed that a proper addition of Zr–Ni (Zr/Ni ⩽ 0.6/12) into Cu could form a large negative lattice distortion, which inhibits Cu–Si interdiffusion and enhances the stability of Cu film. When Fe–Ni was co-added into Cu, the lattice distortion of Cu reached a lower value, 0.0029 Å ⩽ |Δa| ⩽ 0.0046 Å, and the films showed poor stability. Therefore, when the model is applied to the composition design of the films, the strong interaction between the elements and the addition ratio should be taken into consideration.
“…[7][8][9][10][11][12] To overcome this problem, it is now common to add a diffusion barrier between copper and silicon to prevent this reaction. 8,[13][14][15] Nonetheless, as the feature size of ICs shrinks and with increasing demands for interconnect materials with low resistivity, traditional diffusion barriers cannot meet current requirements. [16][17][18][19] Therefore, barrierless Cu metallization methods have been introduced by doping Cu with diffusion-inhibiting elements.…”
The effect of doping different contents of Ni on the thermal stability of Cu(Ni) alloy films has been investigated. Cu(Ni) films with different Ni contents were deposited on SiO 2 /Si substrates by magnetron sputtering, then annealed in vacuum at 350°C to 650°C for 0.5 h. X-ray diffraction analysis and resistance measurements revealed that high-resistance copper silicide was formed after annealing at 450°C for the Cu(Ni, 1.66 at.%) and Cu(Ni, 9.16 at.%) samples. However, no copper silicide was observed for Cu(Ni, 3.59 at.%) even after annealing at 650°C. Transmission electron microscopy provided evidence for a $ 25-nm self-formed barrier layer at the Cu/SiO 2 interface with Cu(Ni, 3.59 at.%). The failure to form a diffusion barrier for the Cu(Ni, 1.66 at.%) sample resulted from its low Ni doping concentration, which was insufficient to produce such a self-formed layer during annealing. The barrier failure was caused by grain refinement due to the increased Ni content, providing diffusion channels for atom diffusion. The results clearly suggest that addition of an appropriate amount of Ni can improve the thermal stability of Cu(Ni)/SiO 2 / Si interconnect structure materials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
