MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE USING SP3-RICH AMORPHOUS CARBON AS HARD MASK

摘要

A method for manufacturing a semiconductor device using sp3-rich amorphous carbon as a hard mask is provided to allow an alignment measurement even if the hard mask is thicker than a preset value. A layer to be etched is formed on a semiconductor substrate. An amorphous carbon film to be used as a first hard mask is deposited on the layer to be etched. A photoresist pattern is formed on the amorphous carbon film. The photoresist pattern is used as an etching mask so that the lower layers are sequentially etched to form a pattern of the layer to be etched. The amorphous carbon film includes a sp3 carbon element bonding structure whose molar fraction is equal to or larger than 45%. The amorphous carbon film is deposited by using a CVD(chemical vapor deposition) scheme in which CH4 + H2 gas is used as a carbon source, the temperature is equal to or lower than 200 degrees Celsius, the pressure ranges from 0.01 to 1 mtorr, and the ion energy ranges from 50 to 500 eV so that the carbon element bonding structure is changed from sp2 structure to sp3 structure.