Nickel silicides formed by low-temperature annealing of compositionally modulated multilayers

A method for making a compound of nickel and silicon, comprising:

• on a surface of a substrate, forming multiple layer pairs in a superposed manner, each layer pair comprising a respective layer of nickel and a respective layer of silicon each being 3 nm or less in thickness, wherein the layers of nickel and silicon in the multiple layer pairs are formed in alternating order, thereby forming a multilayer structure, wherein the layers of nickel and silicon in the multilayer structure are formed at respective thicknesses corresponding to desired mole fractions of nickel and silicon in the multilayer structure;
• annealing the multilayer structure at an annealing temperature of 200° C. or less to form an amorphous alloy of nickel and silicon in the multilayer structure, the alloy having the desired mole fractions of nickel and silicon;
• and
• allowing the amorphous alloy to nucleate and form a corresponding crystalline alloy.

In a microelectronic-device fabrication method, a method for providing a silicon-containing active-circuit element with a low-resistivity contact, the method comprising:

• on a region of the surface of the active-circuit element, forming multiple layer pairs in a superposed manner, each layer pair comprising a respective layer of nickel and a respective layer of silicon each being 3 nm or less in thickness, wherein the layers of nickel and silicon in the multiple layer pairs are formed in alternating order, thereby forming a multilayer structure, wherein the layers of nickel and silicon in the multilayer structure are formed at respective thicknesses corresponding to desired mole fractions of nickel and silicon in the multilayer structure;
• annealing the multilayer structure at an annealing temperature of 200° C. or less to form an amorphous alloy of nickel and silicon in the multilayer structure, the alloy having the desired mole fractions of nickel and silicon;
• and
• allowing the amorphous alloy to nucleate and form a corresponding crystalline alloy.