Structure and Thermal Stability of Copper Nitride Thin Films

Abstract

Copper nitride (Cu 3 N) thin films were deposited on glass via DC reactive magnetron sputtering at various N 2 flow rates and partial pressures with 150 ∘ C substrate temperature. X-ray diffraction and scanning electron microscopy were used to characterize the microstructure and morphology. The results show that the films are composed of Cu 3 N crystallites with anti-ReO 3 structure. The microstructure and morphology of the Cu 3 N film strongly depend on the N 2 flow rate and partial pressure. The cross-sectional micrograph of the film shows typical columnar, compact structure. The thermal stabilities of the films were investigated using vacuum annealing under different temperature. The results show that the introducing of argon in the sputtering process decreases the thermal stability of the films.

Effect of Argon on the Properties of Copper Nitride Fabricated by Magnetron Sputtering for the Next Generation of Solar Absorbers

“…Figure 4 presents plan-view FESEM images of the Cu 3 N films deposited in the N 2 + Ar environment (Figure 4a) and in the pure N 2 atmosphere (Figure 4b). morphology, indicative of a competition between the (111) and (100) orientations, as revealed by the XRD patterns (Figure 2) [32]. The RMS values calculated for these samples were 3.03 nm (S1) and 5.12 nm (S2).…”

“…This effect can be attributed to the increase in the deposition rate due to the introduction of Ar into the plasma, and also to the competition between the grain orientations present in the films, which led to changes in the morphology. Hence, the samples deposited in the N 2 + Ar environment (Figure 3a) showed a large number of void boundaries embedded in a complex pyramidal conical morphology, indicative of a competition between the (111) and (100) orientations, as revealed by the XRD patterns (Figure 2) [32]. The RMS values calculated for these samples were 3.03 nm (S1) and 5.12 nm (S2).…”

“…The shape of these grains turned out to be more spherical when the sample was deposited in a pure N 2 atmosphere. On the other hand, at the highest pressure of 5.0 Pa, the grains on the surface appeared to gain a nodular-like morphology, and this was once again oversized on the surface of the sample deposited in the mixed environment [32]. This morphology was characterized by the presence of a flat block of particles of uniform size, without visible cracks.…”

A Low-Cost Passivation for Low Temperature Cu-Cu Bonding Using PVD-Deposited Cu3N

“…CuN, applied as a surface protection layer, has been reported using a two-step plasma treatment method and demonstrated blanket Cu-Cu bonding at 260℃ [15], [16]. It has been proposed that CuN exhibits stability at room temperature but decomposes into Cu and N2 when heated [17]- [19]. These characteristics make CuN suitable for protecting Cu from oxidation and achieving good Cu-Cu joint during the bonding process.…”