Silicon films deposited on flexible substrate by hot-wire chemical-vapor deposition

• Cyclic olefin copolymer (COC) is a lower water vapor transmission rate of polymer.
• The microcrystalline silicon is grown on COC substrate at low deposited temperature.
• The crystallinity of silicon films can be effect by hydrogen dilution.
• The lower WVTR of flexible substrate could avoid the post-oxidized of silicon film.

Silicon film was deposited on a novel flexible polymer, cyclic olefin copolymer (COC), by using hot-wire chemical-vapor deposition at a low substrate temperature and increasing hydrogen-dilution ratios (DH: 0%–95%). The crystallinity of the silicon film coated on a COC substrate increased, changing from amorphous to microcrystalline, accompanying the rising hydrogen-dilution ratio. The surface morphology of the deposited silicon film varied according to the hydrogen-dilution ratio, with roughness values of the silicon film increasing from 4.20 to 6.51 nm. This study examined the effect of hydrogen-dilution ratios on the crystallinity, surface roughness, and optical-absorption properties of silicon films.