Deposition methods using pulsed plasma with varying pulse frequency

A method for processing a substrate, the method comprising:

• loading a substrate into a process chamber;
• performing a first deposition process, the first deposition process comprising:
• flowing a first process gas into the process chamber;
• and
• exposing the substrate to the first process gas to deposit a first layer;
• performing a second deposition process, the second deposition process comprising:
• flowing a second process gas into the process chamber;
• powering a source electrode of the process chamber with source power pulses to generate a plasma, the source power pulses having a repetition frequency;
• exposing the substrate to the plasma to convert the first layer into a material layer;
• and
• while exposing the substrate to the plasma, changing the repetition frequency continuously and monotonically.

A method for processing a substrate, the method comprising:

• loading a substrate into a process chamber;
• generating source power pulses having a pulse frequency that varies continuously and monotonically from a first frequency to a different second frequency;
• performing a cyclic deposition process comprising a plurality of deposition cycles, one of the deposition cycles comprising:
• performing a first deposition process, the first deposition process comprising:
• flowing a silicon precursor with formula SinH2n+2−mClm (n≥1 and 0≤m≤2n+2) into the process chamber;
• and
• exposing the substrate to the silicon precursor to deposit a silicon layer;
• and
• performing a second deposition process, the second deposition process comprising:
• flowing a nitrogen precursor into the process chamber;
• powering a source electrode of the process chamber with the source power pulses to generate a plasma;
• and
• while varying the pulse frequency applied to the source electrode continuously and monotonically from the first frequency to the second frequency, exposing the substrate to the plasma to deposit a nitride layer.