Method of forming a semiconductor device

A method for forming a semiconductor device comprising:

• attaching a wafer comprising a carbon-rich hard masking layer, disposed over a target layer, the carbon-rich hard masking layer and target layer disposed on a semiconductor substrate, to a fixture in an ion implant device or an ion beam etching device wherein the carbon-rich hard masking layer is patterned to form features in the carbon-rich hard masking layer;
• and
• performing a directional ion beam trimming process on the features patterned in the carbon-rich hard masking layer wherein the directional ion beam trimming process further comprises reshaping an end of one or more features patterned in the carbon-rich hard masking layer from substantially triangular in shape to substantially square in shape.