THERMALLY INDUCED CHANGES IN THE RESISTANCE, MICROSTRUCTURE, AND ADHESION OF THIN GOLD-FILMS ON SI SIO2 SUBSTRATES

The resistance as a function of annealing temperature for thin gold films on a Si02 layer on silicon (100) passes through a minimum near 600 °C for times at temperature < 60 min. The structural changes associated with this electrical behavior have been investigated by scanning tunneling microscopy and scanning electron microscopy. Annealing temperatures as low as 100 °C affect the microstructure as well as reducing the resistance. Recrystallization and grain growth occur with increasing temperature, and the high surface energy of gold relative to SiO2 results in nucleation and growth of porosity above about 600 °C which contributes to an abrupt increase in resistance. The adhesion of gold to SiO2 was improved at elevated temperatures (> 600 °C). © 1990, American Vacuum Society. All rights reserved.