Patent ID: 6770563
Filing Date: 2004-08-03
Classification: H01L

Abstract:
A process of forming a bottle-shaped trench comprising:providing a semiconductor substrate, on the surface of which a pad layer, a hard mask layer, and a patterned insulating layer having an opening exposing the surface of the hard mask layer are all sequentially formed; sequentially etching the hard mask layer, the pad layer, and the semiconductor substrate to form a trench using the patterned insulating layer as a mask; removing the patterned insulating layer; forming a spin-on glass layer on the hard mask layer, filling the trench without an interviewing layer between the semiconductor substrate and the spin-on glass layer; anisotropically etching the spin-on glass in the trench to a predetermined depth, such that the spin-on glass on the surface of the hard mask layer is totally removed; conformally forming an insulating layer on the surface of the hard mask layer and the trench; anisotropically etching the insulating layer to form a spacer on the sidewall of the trench and exposing the surface of the spin-on glass; wet etching the semiconductor substrate to remove the spin-on glass; and isotropically etching the trench, unmasked by the spacer, to a bottle shape.