Method for isolating semiconductor elements

Claim 1

A method for forming an active region and a field region in a semiconductor device comprising the steps of: forming a pad oxide layer and a first nitride layer on a semiconductor substrate, and defining an active region pattern by etching the pad oxide layer and the first nitride layer where the field region is to be formed; removing a portion of the pad oxide layer underlying the first nitride layer along the edge of the active region pattern; forming a conformal silicon layer, wherein the silicon layer fills the space where the pad oxide layer underlying the first nitride layer had been removed; forming a second nitride layer and etching the second nitride layer to form a side wall of nitride on the vertical surface of the silicon layer adjacent the edge of the field region; oxidizing the silicon substrate to form a first field oxide layer; removing the side wall of nitride, and carrying out a field channel stop ion implantation; and oxidizing to form a second field oxide layer.

Claim 2

A method for forming an active region and a field region in a semiconductor device comprising the steps of: forming a pad oxide layer and a first nitride layer on a semiconductor substrate, and defining an active region pattern by etching the pad oxide layer and the first nitride layer where the field region is to be formed; removing a portion of the pad oxide layer underlying the first nitride layer along the edge of the active region pattern; forming a conformal silicon layer, wherein the silicon layer fills the space where the pad oxide layer underlying the first nitride layer had been removed; forming a second nitride layer and etching the second nitride layer to form a side wall of nitride on the vertical surface of the silicon layer adjacent the edge of the field region; oxidizing the silicon substrate to form a first field oxide layer; removing the side wall of nitride, and carrying out a field channel stop ion implantation; and oxidizing to form a second field oxide layer.

Claim 14

A method for isolating an active region from a field region in a semiconductor device comprising the steps of: forming a pad oxide layer and a first nitride layer on a semiconductor substrate, and defining an active region pattern by selectively removing the pad oxide layer and the nitride layer where the field region is to be formed; removing a portion of the pad oxide layer between the silicon substrate and the nitride layer along the edge of the active region pattern; forming a conformal silicon layer, wherein the silicon layer fills the space where the pad oxide layer had been removed along the edge of the active region pattern; forming a second nitride layer and etching the second nitride layer to form a side wall of nitride on the vertical surface of the silicon layer adjacent the edge of the field region; carrying out a field channel stop ion implantation, and oxidizing the silicon substrate to form a first field oxide layer; and removing the side wall of nitride, and oxidizing to form a second field oxide layer.

Claim 15

A method for isolating an active region from a field region in a semiconductor device comprising the steps of: forming a pad oxide layer and a first nitride layer on a semiconductor substrate, and defining an active region pattern by selectively removing the pad oxide layer and the nitride layer where the field region is to be formed; removing a portion of the pad oxide layer between the silicon substrate and the nitride layer along the edge of the active region pattern; forming a conformal silicon layer, wherein the silicon layer fills the space where the pad oxide layer had been removed along the edge of the active region pattern; forming a second nitride layer and etching the second nitride layer to form a side wall of nitride on the vertical surface of the silicon layer adjacent the edge of the field region; carrying out a field channel stop ion implantation, and oxidizing the silicon substrate to form a first field oxide layer; and removing the side wall of nitride, and oxidizing to form a second field oxide layer.

Claim 27

A method for isolating an active region from a field region in a semiconductor device, comprising the steps of: forming a pad oxide layer and a first nitride layer on a silicon substrate, and forming an active region pattern by removing portions of the pad oxide layer and the first nitride layer in the field region; exposing the pad oxide layer to an etchant to etch a portion of the pad oxide layer at the edge portion of the field region, and forming a conformal polysilicon layer, wherein the polysilicon layer is formed in the etched-away portion of the pad oxide layer; forming a nitride layer side wall on the vertical surface of the silicon layer adjacent the edge of the field region; and performing a first field oxidation to form a first field oxide layer, removing the nitride side wall layer, implanting field channel stop ions in the field region, and performing a second field oxidation to form a second field oxide layer.

Claim 28

A method for isolating an active region from a field region in a semiconductor device, comprising the steps of: forming a pad oxide layer and a first nitride layer on a silicon substrate, and forming an active region pattern by removing portions of the pad oxide layer and the first nitride layer in the field region; exposing the pad oxide layer to an etchant to etch a portion of the pad oxide layer at the edge portion of the field region, and forming a conformal polysilicon layer, wherein the polysilicon layer is formed in the etched-away portion of the pad oxide layer; forming a nitride layer side wall on the vertical surface of the silicon layer adjacent the edge of the field region; and performing a first field oxidation to form a first field oxide layer, removing the nitride side wall layer, implanting field channel stop ions in the field region, and performing a second field oxidation to form a second field oxide layer.