摘要 |
A method of forming a trench type isolation layer is provide, wherein the method comprises: forming a trench by etching after forming a trench etching pattern on a substrate; forming a silicon nitride liner on an inner wall of the trench; filling the trench with a first buried oxide layer; exposing an upper part of the liner of the trench by recessing the first buried oxide layer using a wet process; removing the upper part of the silicon nitride liner using isotropic etching; and filling the recessed space of the trench with a second buried oxide layer. The method may further comprise: forming the trench etching pattern by depositing and patterning a silicon nitride layer, and forming a thermal oxide layer, preferably through annealing, for healing etching defects on an inner wall of the trench, between forming the trench and forming the liner.
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