Formation of Aluminum Microsphere by Utilizing Atomic Migration

A technique using the sudden change in the geometrical shape of metal line is considered for effective accumulation of atoms, and therefore fabrication of micro/nano materials utilizing electromigration. The experimental sample of Al metal line is formed on a TiN layer and covered with a SiO2 passivation layer. Thereafter, the sample is placed on a ceramic heater under atmospheric conditions, and subjected to a constant direct current for fabricating micro/nano materials. Finally, microsphere was obtained at the specific location in the sample with a sudden change in geometrical shape where a hole was introduced in the SiO2 passivation and Al layers. Therefore, the temperature distribution was observed along the metal line of the proposed Al sample structure. As a result of current applying, the sphere of a high aspect ratio was fabricated.