Method and Apparatus for the Planarization of Surfaces

A method comprising;

• orienting a surface of a sample to a charged particle beam axis, the sample including a first layer, the first layer formed from first and second materials, the first material different than the second material and patterned into a plurality of parallel lines that are disposed in the second material, wherein a top surface of the second material forms the surface, and wherein the surface is oriented to form a shallow angle with the charged particle beam axis and to arrange the plurality of parallel lines so that a long side of the plurality of parallel lines extends across the charged particle beam axis;
• providing a charged particle beam along the charged particle beam axis toward the surface of the sample;
• providing a gas to the surface of the sample;
• and
• selectively etching, with ion induced chemical etching, the second material at least down to a top surface of the first material, the charged particle induced etching stimulated due to concurrent presence of the charged particle beam and the gas over the surface of the sample.