Method and apparatus for neutral beam processing based on gas cluster ion beam technology

A method for processing a trench structure having a proximate opening and a distal base or bottom material therein having an exposed surface accessible through said opening via the trench structure interior, comprising the steps of:

• providing a reduced pressure chamber;
• forming a gas cluster ion beam comprising gas cluster ions within the reduced pressure chamber;
• accelerating the gas cluster ions to form an accelerated gas cluster ion beam along a beam path within the reduced pressure chamber;
• promoting fragmentation and/or dissociation of at least a portion of the accelerated gas cluster ions along the beam path by increasing the range of velocities of ions in the accelerated gas cluster ion beam;
• removing charged particles from the beam path to form an accelerated neutral beam along the beam path in the reduced pressure chamber;
• holding a workpiece comprising the trench structure in the beam path;
• and
• treating the base material surface by directing the neutral beam path through the trench structure opening and toward the surface base or bottom material to irradiate all or part of the said surface of the base or bottom material of the trench structure.