Preparation of TaN Thin Film by H2 Plasma Assisted Atomic Layer Deposition Using Tert-Butylimino-Tris-Ethylmethylamino Tantalum

Abstract

The plasma assisted atomic layer deposition (ALD) of tantalum nitride (TaN) thin films were conducted using tert-butylimino-tris-ethylmethylamino tantalum (TBTEMAT) and hydrogen plasma at 250 °C. The effects of H2-plasma pulse time and RF power on the film properties, such as resistivity, surface roughness, step coverage and stability in air, were examined. The film growth rate (thickness/cycle) was in the range of 0.05–0.08 nm/cycle and the resistivity of the films varied from 490 to 70000 μΩ cm, depending on the plasma conditions. Longer plasma pulse times and increasing RF power yielded films of lower resistivity along with improving the stability. The films were smooth and the conformality of the films deposited in 0.28 μm holes with an aspect ratio of 7:1 was 100%.