Ageing of thin gold films

Abstract

Thin gold metallizations are used in microelectronic devices when high reliability is required. Experience has shown that the operating lives of transistors and monolithic integrated circuits with high power dissipation, and of ultra-highfrequency devices such as microwave integrated hybrid circuits, are Longest when gold is used in the manufacture of their interconnections. With gold, the probability of zero-hour failures and of degradation under thermal and electrical bad, and in corrosive environments, is very low. The reasons for the high reliability of thin gold metallizations are to be found in the chemical stability of the metal, in the fact that ik is not very sensitive to diffusion from other metallizations and in the esse with which connections can be made to is by microwelding (1, 2, 3).

Rapid annealing of Au thin films by micron chevron-shaped laser beam scanning toward growth of single-grain crystal

“…In the past, solid-state crystal growth in metal thin films by furnace annealing had been reported for Al, 13) Au, 14,15) Cu, 16) and Ag. 17,18) The as-deposited metal films usually have equiaxed grain structures with mean grain size smaller than the film thickness.…”

“…17,18) The as-deposited metal films usually have equiaxed grain structures with mean grain size smaller than the film thickness. [13][14][15][16][17][18][19][20] During annealing or even during keeping at normal temperature, three-dimensional normal grain growth (c occurs. The driving forces for normal grain growth are reduction of grain boundary energy, reduction of surface energy, and reduction of elastic strain energy.…”

The science and technology of gold

“…In regard to their physical attributes, diffusion between them and various substrates and films of other metals, electrical properties, electromigration, etc. have been especially significant technically and have been much investigated as an integral part of the development of the use of such thin film systems in microelectronic devices [39][40][41][42][43][44].…”

Selective Removal of Gold: N-Heterocyclic Carbenes as Positive Etch Resists on Planar Gold Surfaces

“…Although this phenomenon could not be observed using a cyanide solution, we found no reports regarding the undercut in TU solutions. It should be noted that we used an adhesive layer of Cr as well because it was the standard in our previous studies. , In addition to the abnormal undercut, Cr is known for diffusing into the Au layer when used as an adhesive. − To exclude the interdiffusion of Cr as a possible reason for the etching behavior found in this study, the experiments were additionally conducted with Ti as the adhesive layer. Indeed, the result changed insofar that the time for complete etching increased from 3 to 6 min (correlating with an etch rate of around 160 Å/min).…”