Method and system for forming patterned structures using multiple patterning process

A method of forming patterned structures using a multiple patterning process, the method comprising the steps of:

• providing a substrate within a reaction chamber, the substrate comprising a surface comprising patterned features;
• and
• forming a layer overlying the substrate, wherein the step of forming the layer comprises:
• depositing a material, wherein the step of depositing the material comprises:
• providing a precursor to the reaction chamber for a precursor pulse period;
• providing a reactant to the reaction chamber for a reactant pulse period;
• and
• applying a first plasma power, having a first frequency less than 1 MHz for a first plasma power period, and a second plasma power, having a second frequency, for a second plasma power period, wherein the first frequency is different than the second frequency, and wherein the first plasma power period and the second plasma power period overlap;
• and
• treating the deposited material, wherein the step of treating the deposited material comprises:
• providing an oxygen-free gas to the reaction chamber;
• and
• applying a third plasma power for a third plasma power period to form activated species from the oxygen-free gas to treat the deposited material to thereby form treated material.