The effects of diborane (B2H6) pretreatment on atomic layer deposition (ALD) of tungsten (W) thin film using a sequential supply of WF6 and SiH4 on thermally grown SiO2 and TiN films at 300°C were investigated. The results show that the B 2H6 pretreatment reduces the incubation time for film growth. X-ray photoelectron spectroscopy and scanning electron microscopy analysis suggest that elemental B on SiO2, released during B 2H6 pretreatment, induce rapid W nucleation. The drastically improved step coverage of ALD-W film is achieved at the ultrahigh aspect ratio contact (height: 2.23 μm and top diameter: 0.14 μm) by the enhanced nucleation and growth via B2H6 pretreatment. The effects of B2H6 pretreatment on the properties of ALD-W films such as roughness, phase, microstructure, and resistivity are also investigated.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering