Silicides and ohmic contacts

Structural and electrical characterization of the nickel silicide films formed at 850°C by rapid thermal annealing of the Ni/Si(100) films

“…In recent years nickel silicides, intermetallic compounds of silicon and nickel, have been proposed as candidates for replacing aluminum alloys for applications in very large-scale integrated circuits (VLSI) [1][2][3][4] and in ultra large-scale integrated circuits (ULSI) [3][4][5], because they show metallic behavior with low electrical resistivity, high electro-migration resistance, high thermal stability and resistance to acids [1,4]. Nickel silicides can be formed by solid-state reaction of Si and thin nickel films, deposited on Si wafer, at a temperature well below the eutectic temperature of the system [6][7][8][9][10][11][12], although other techniques such as explosive silicidation [13], reactive deposition [14] and ion implantation [15][16][17] can also be used.…”

Nickel Silicide Nanowire Growth and Applications

“…Chemical analysis revealed that the Ni to Si ratio has a gradient from bottom to surface of the layer. The reaction of Ni and Si causes the compressive stress by volume changes at the silicide interface (Gergaud et al, 2003;Gambino & Colgan, 1998) as well as by the different mobility between the Ni and Si (Gambino & Colgan, 1998). The Si bonds are softened by intermixing of Si and Ni atoms and existing Ni in the interface of Ni and Si (Ottaviani, 1981).…”

“…This implies that the reaction of Ni and Si controls the silicide formation. Due to the equilibrium phase is determined by the ratio of Ni atoms to Si atoms (Gambino & Colgan, 1998), the thinner film tends to be a Si rich silicide and the thicker film prefers to be a Ni rich phase (Julies et al, 1999;Zheng et al, 1983). Thermodynamically, the large grains get larger by the tendency to reduce the surface free energy.…”

Pulsed Current Activated Synthesis and Consolidation of Nanostructured MoSi₂–NbSi₂ Composite and Its Mechanical Properties

“…5) In addition, the disilicide has found wide applications as a thin film in microelectronics, as a result of its high electrical conductivity, high-temperature stability, corrosion resistance, and the ability to form good contacts with silicon. 6,7) However, as in the case of many similar compounds, the current concern about these materials (MoSi 2 and NbSi 2 ) focuses on their low fracture toughness below the ductile-brittle transition temperature.…”