In situ POCl3-doped interlevel oxidation

A novel in situ POCl3-doped interlevel (IPI) method is described, in which the oxide grown during POCl3predeposition is used as the interlevel oxide. This scheme is contrary to the conventional process flow with the stripping of the oxide (phosphorus-doped silicon glass (PSG) grown during POCl3predeposition before the real interlevel oxide is grown. The new "in situ POCl3-doped" interlevel Oxidation scheme results in a simplified process flow. It is shown that good-quality interlevel oxide can be obtained by properly incorporating the POCl3predeposition into the interlevel oxidation cycle. A 38-nm oxide with a tight breakdown distribution around 24 V and leakage of 5.E-9 Amp/cm²at 12 V is demonstrated.