摘要
Effect of C：F deposition on SiCOH etching in a CHF3 dual-frequency capacitively couple plasma, driven by a high-frequency source of 60 MHz （HF） and a low-frequency source of 2 MHz （LF） simultaneously, is investigated. With the increase in LF power, the change of C：F layer from dense C：F layer to porous C：F layer and further to C：F filling gaps was observed, which led to the transition from films deposition to films etching. The change of C：F layer is related to the bombardment by energetic ions and CF2 concentration in the plasma. As the LF power increased to 35 - 40 W, the energetic ions and the low CF2 concentration led to a suppression of C：F deposition. Therefore, the SiCOH films can be etched at higher LF power.
Effect of C：F deposition on SiCOH etching in a CHF3 dual-frequency capacitively couple plasma, driven by a high-frequency source of 60 MHz （HF） and a low-frequency source of 2 MHz （LF） simultaneously, is investigated. With the increase in LF power, the change of C：F layer from dense C：F layer to porous C：F layer and further to C：F filling gaps was observed, which led to the transition from films deposition to films etching. The change of C：F layer is related to the bombardment by energetic ions and CF2 concentration in the plasma. As the LF power increased to 35 - 40 W, the energetic ions and the low CF2 concentration led to a suppression of C：F deposition. Therefore, the SiCOH films can be etched at higher LF power.
基金
supported by National Natural Science Foundation of China (Nos.10575074, 10635010)
