Patent ID: 7435653
Filing Date: 2008-10-14
Classification: H01L

Abstract:
1. A method for forming a wrap-around-gate field-effect transistor on a handle wafer, the method comprising: forming a silicon-on-insulator (SOI) structure on the handle wafer, the SOI structure including a semiconductor island between a first oxide layer and a second oxide layer, and the semiconductor island extending, for a length, along a major axis in a horizontal direction between first and second end portions; forming a vertical cavity in the SOI structure extending from a top surface of the SOI structure to the handle wafer, the cavity having substantially vertical sidewalls and intersecting the semiconductor island; isotropically etching the first oxide layer and the second oxide layer within the cavity thereby exposing surface portions of the semiconductor island; depositing a gate conductor material on the surface portions of the semiconductor island; and isotropically etching the gate conductor material to recess the gate conductor material in the horizontal direction relative to the surface portions of the semiconductor island to form a wrap-around gate electrode having a thickness, in the horizontal direction, less than the length of the semiconductor island such that the first end portion of the semiconductor island extends on one side of the gate electrode and the second end portion of the semiconductor island extends on another side of the gate electrode and extending entirely around a surface periphery of the silicon island such that a portion of the gate electrode is disposed in a gap between the semiconductor island and the handle wafer.