The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 02, 2006
Filed:
Dec. 16, 2003
Toni D. Van Gompel, Austin, TX (US);
Mark D. Hall, Austin, TX (US);
Mohamad Jahanbani, Austin, TX (US);
Michael D. Turner, San Antonio, TX (US);
Toni D. Van Gompel, Austin, TX (US);
Mark D. Hall, Austin, TX (US);
Mohamad Jahanbani, Austin, TX (US);
Michael D. Turner, San Antonio, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A method for forming trench isolation in an SOI substrate begins with a pad oxide followed by an antireflective coating (ARC) over the upper semiconductor layer of the SOI substrate. The pad oxide is kept to a thickness not greater than about 100 Angstroms. An opening is formed for the trench isolation that extends into the oxide below the upper semiconductor layer to expose a surface thereof. The pad oxide is recessed along its sidewall with an isotropic etch. This is followed by a thin, not greater than 50 Angstroms, oxide grown along the sidewall of the opening. This grown oxide avoids forming a recess between the ARC and the pad oxide and also avoids forming a void between the surface of the lower oxide layer and the grown oxide. This results in avoiding polysilicon stringers when the subsequent polysilicon gate layer is formed.