Abstract: The oxynitride or oxide layer formed on a semiconductor substrate is pre-treated with UV-excited gas (such as chlorine or nitrogen) to improve the layer surface condition and increase the density of nucleation sites for subsequent silicon nitride deposition. The pre-treatment is shown to reduce the root mean square surface roughness of thinner silicon nitride films (with physical thicknesses below 36 Å, or even below 20 Å that are deposited on the oxynitride layer by chemical vapor deposition (CVD).

Abstract: Systems and methods are described for semiconductor wafer pretreatment. A method of treating a semiconductor wafer, includes contacting the semiconductor wafer with a mixture including HF and CH3OH; and then contacting the semiconductor wafer with Cl2 and simultaneously exposing said semiconductor wafer to a source of ultraviolet energy. The selective HSG temperature of formation window is widened. In addition, robustness with regard to changes in the reactor ambient and substrate condition, and selectivity with regard to underlying dielectric layers, are both improved.

Abstract: Systems and methods are described for semiconductor wafer pretreatment. A method of increasing the selectivity of silicon deposition with regard to an underlying oxide layer during deposition of a silicon containing material by broadening a selective temperature of formation window for said silicon containing material by decreasing a lower temperature endpoint includes: providing a semiconductor wafer with the underlying oxide layer in a processing chamber; then pumping water from then processing chamber; and then depositing the silicon containing material on the semiconductor wafer. A step of seeding the semiconductor wafer can be conducted by exposing the semiconducotor wafer to a germanium containing gas. A chlorine containing precursor and/or hydrogen can be introduced into the processing chamber to increase the selectivity of the silicon containing material to the underlying oxide. The selective HSG temperature of formation window is widened.