Two-Step Deposition Method for Improvement of the Electrical Characteristics of BST Thin Films

The characteristics of the BST thin films deposited by two-step deposition process were investigated. A 100 Å thick bottom layer was deposited at 600 C° and then upper main layer was in-situ deposited at 350 C° by rf magnetron co-sputtering, respectively. Two-step deposited BST thin film of 500 Å showed lower lealwge current density of 2 X 10
^-3
A/cm
²
at 1.5V and more wide flat region in the low field than those of BST thin film deposited by one step process, and small silicon oxide equivalent thickness of 4.9 Å. With the decrease of film thickness, equivalent oxide thickness which is about 5.4 Å for the film with thickness of 1000 A can be reduced to 4.2 Å for 200 Å.