METHOD FOR FABRICATING HIGHLY CONDUCTIVE SILICON LINES

摘要

A narrow silicon line which can be in the form of a gate pattern (30) is defined in a thin layer (16) of silicon on a semiconductor element (¦0) by applying a narrow ion beam (22) as provided by a focused-ion-beam source (24). The beam contains an ion which is a dopant in silicon. The layer (18) of silicon overlies a film (16) of oxide on a silicon or indium phosphide substrate (12). The ion beam can have a submicrometer dimension, can be translated to pattern a gate or interconnect line. The dopant ions are implanted into the polysilicon layer and thereby render the exposed portions of the layer preferentially insoluble to wet etchant. The non-exposed portions are preferentially removed to form a line or a gate (30). Standard FET processing may then be performed to provide source (32) and drain regions (34) as necessary to form a transistor device.