Patent ID: 7696051
Filing Date: 2010-04-13
Classification: H01L

Abstract:
1. A method of fabricating a MOSFET, in which a gate insulating layer pattern, a gate conductive layer pattern having exposed sidewalls, and a mask pattern having an exposed surface are sequentially stacked on a first region of a semiconductor substrate, and a second region of the semiconductor substrate is recessed by a predetermined thickness during an etch process using the mask pattern for forming the gate insulating layer pattern and the gate conductive layer pattern, the method comprising: forming a first insulating layer on the second region of the semiconductor substrate, the exposed sidewalls of the gate conductive layer pattern, and the exposed surface of the mask pattern; forming a second insulating layer on the first insulating layer; forming a first insulating pattern and a second insulating pattern by etching the first insulating layer and the second insulating layer so as to expose a top surface of the mask pattern and a portion of a surface of the second region spaced apart from the first region; substantially completely exposing the second region by etching the first insulating pattern so as to remove part of a surface of the first insulating pattern contacting the semiconductor substrate; growing an epitaxial layer over the exposed second region; removing the mask pattern, the second insulating pattern, and the first insulating pattern so as to expose a surface of the epitaxial layer and a top surface and sidewalls of the gate conductive layer pattern; forming an ion implantation buffer layer on the exposed surface of the epitaxial layer and a surface of the gate conductive layer pattern; forming a lightly-doped impurity region in the epitaxial layer and the semiconductor substrate by performing a first ion implantation process; removing the ion implantation buffer layer so as to expose the lightly-doped impurity region and a top surface and sidewalls of the gate conductive layer pattern; sequentially forming a third insulating layer and a fourth insulating layer on the exposed surfaces of the lightly-doped impurity region and the gate conductive layer pattern; forming spacers by etching the third insulating layer and the fourth insulating layer so as to expose part of the surface of the epitaxial layer; and forming a heavily-doped impurity region in the epitaxial layer and the semiconductor substrate by performing an ion implantation process using the spacers as an ion implantation mask.