portions 210 a of the pad oxide layer 210 remain after the hardmask pullback following the pullback etch the photoresist layer 225 and the barc layer 220 are preferably removed in the same plasma tool using a conventional plasma etch after the hardmask pullback step and the removal of the photoresist and barc layers 225 and 220 a conventional plasma etch is conducted to form a trench 230 in the substrate 205 as shown in fig2 f in one particular embodiment the plasma etch is a silicon plasma etch that may be conducted at a source power ranging from about 250 watts to about 450 watts a bias power of ranging from about 100 watts to about 200 watts and by using an etching gas comprising gases like cl 2 o 2 n 2 etc wherein a flow rate of each of these gases ranges from about 25 sccm to about 180 sccm subsequent to the formation of the trench 230 the semiconductor device 200 is in an advantageous embodiment moved from the plasma tool to a furnace an oxide liner 235 which is also shown in fig2 f is conventionally grown and is followed by an oxide liner anneal.