Techniques for processing a polycrystalline layer using an angled ion beam

A method of processing a layer disposed on a substrate, comprising:

• directing an ion beam to an exposed surface of the layer in a first ion exposure when the substrate is disposed in a first rotational position, the ion beam having a first ion trajectory forming a non-zero angle of incidence with respect to a perpendicular to a substrate plane;
• scanning, during the first ion exposure, the substrate in a first scan along a scan direction, the scan direction lying in the substrate plane;
• performing a rotation by rotating the substrate with respect to the ion beam about the perpendicular from the first rotational position to a second rotational position;
• directing the ion beam to the exposed surface of the layer in an additional ion exposure along the first ion trajectory, when the substrate is disposed in the second rotational position;
• and
• scanning, during the additional ion exposure, the substrate in a second scan along the scan direction.

A method of processing a metal layer, comprising:

• providing a substrate comprising the metal layer and a buried feature, wherein the metal layer is disposed over the buried feature;
• directing an ion beam to an exposed surface of the metal layer in an ion exposure when the substrate is disposed in a first rotational position, the ion beam having a first ion trajectory forming a non-zero angle of incidence with respect to a perpendicular to a substrate plane;
• scanning, during a first ion exposure, the substrate in a first scan along a scan direction, the scan direction lying in the substrate plane;
• performing a rotation by rotating the substrate with respect to the ion beam about the perpendicular from the first rotational position to a second rotational position;
• directing the ion beam to the exposed surface of the layer in a second ion exposure along the first ion trajectory, when the substrate is disposed in the second rotational position;
• and
• scanning, during the second ion exposure, the substrate in a second scan along the scan direction.