Step Coverage in Evaporated Films
Original Publication Date: 1982-Aug-01
Included in the Prior Art Database: 2005-Feb-10
When thin films are to be deposited over steps in a substrate, the coverage is often poor due to development of cracks in the deposited film at the step edges. These cracks cause problems with successive overlayers and are paths for corrosion of underlying layers. One technique to solve this problem uses ion bombardment during film deposition in order to resputter and redistribute the depositing atoms sideways in order to fill in the cracks. In the present article a different technique is described which uses Ion bombardment to prevent the development of overhanging edges at the top of the steps, thereby eliminating the growth of the cracks. The ion beam angle, energy, and flux are chosen to optimize this process.