System and Method for Atomic Layer Etching and Radical-Based Highly Selective Etching in a Single Process Chamber

A method for processing a substrate, the method comprising:

• providing a plasma process chamber, comprising an upper chamber and a lower chamber separated by a GIF, wherein the chamber further comprising a plasma source configured to generate an inductively coupled plasma in the upper chamber, a bias unit, connected to a chuck, for generating a capacitively coupled plasma in the lower chamber, a first gas/precursor distribution unit, and a second gas/precursor distribution unit;
• performing by a system controller an ALE process, comprising:
• operating the chamber in a surface modification step, wherein the plasma source generates the inductively coupled plasma in the upper chamber, wherein the GIF blocks ions from the plasma from entering the lower chamber while allowing neutrals entering the lower chamber to modify the substrate surface;
• operating the chamber in a sputtering step, wherein the bias unit generates the capacitively coupled plasma in the lower chamber, wherein the ions in the plasma are accelerated by a voltage bias caused by the bias unit to remove the modified layer;
• and
• performing by the system controller a radical-based HSE process, comprising:
• operating the chamber for the radical-based HSE process, wherein the plasma source generates an inductively coupled plasma in the upper chamber, the GIF blocks ions from the plasma from entering the lower chamber while allowing neutrals from the plasma to modify the substrate surface and remove the modified layer.

A method of forming a pattern on a substrate, the method comprising:

• providing a plasma process chamber comprising an upper chamber and a lower chamber separated by a GIF, the chamber further comprising a plasma source configured to generate a plasma in the upper chamber, a bias unit operatively connected to a chuck in the lower chamber, a gas distribution unit, and a controller;
• receiving a substrate with a defined layer of mask on top of a targeted layer material to be etched, wherein said layer of mask further includes one or more materials;
• performing an ALE process to etch the stack of the materials, comprising:
• a) operating the plasma source to generate an inductively coupled plasma in the upper chamber while ceasing to supply RF power to the bias unit, such that ions from the plasma are blocked by the GIF and only neutrals from the plasma are allowed to pass through the GIF and modify a surface of the substrate in the lower chamber;
• b) introducing an inert gas into the lower chamber and operating the bias unit to supply RF power to the bias unit, thereby igniting a plasma in the lower chamber and converting it into a CCP reactor, wherein ions from the plasma are accelerated towards the substrate to remove the modified surface layer;
• c) repeating the surface modification and the sputtering steps until the targeted layer of the material is removed;
• and
• performing a radical-based HSE process, comprising:
• a) introducing a gas or a precursor to the upper chamber;
• b) operating the plasma source to generate an inductively coupled plasma in the upper chamber while ceasing to supply RF power to the bias unit, such that ions from the plasma are blocked by the GIF and neutrals from the plasma are allowed to pass through the GIF and modify the surface of the mask in the lower chamber and subsequently remove the one or plurality of layers for the mask.