公开(公告)号：CA1250669A1

公开(公告)日：1989-02-28

申请号：CA549183

申请日：1987-10-13

Applicant: IBM

Inventor： GIAMMARCO NICHOLAS J ,  GIMPELSON ALEXANDER ,  KAPLITA GEORGE A ,  LOPATA ALEXANDER D ,  SCADUTO ANTHONY F ,  SHEPARD JOSEPH F

IPC: H01L21/302 ,  G03F7/40 ,  H01L21/027 ,  H01L21/033 ,  H01L21/266 ,  H01L21/30 ,  H01L21/3065 ,  H01L21/308 ,  H01L21/70

Abstract: Disclosed is a process for reducing lithographic image size for integrated circuit manufacture. A mask of photosensitive material having an opening of a minimum size dictated by the limits of lithography is formed on a substrate. Reduction in the image size is achieved by establishing sidewalls to the interior vertical surfaces of the opening by depositing a conformal layer, followed by anisotropic etching. The dimension of the opening is reduced by the combined thickness of the two opposite insulator sidewalls. In a specific direct application of the disclosed process, a photomask/stencil having a pattern of openings of a minimum size smaller than possible by lithography, per se, is formed.

公开(公告)号：CA1286572C

公开(公告)日：1991-07-23

申请号：CA534158

申请日：1987-04-08

Applicant: IBM

Inventor： FULTON INGE G ,  MAKRIS JAMES S ,  NASTASI VICTOR R ,  SCADUTO ANTHONY F ,  SHARTEL ANNE C

IPC: H01L21/76 ,  H01L21/74 ,  H01L21/762 ,  H01L21/763 ,  H01L21/31 ,  H01L21/311

Abstract: Disclosed is a process of growing a conformal and etch-resistant silicon dioxide on a surface by forming a conformal layer of polysilicon and subjecting the polysilicon to thermal oxidation to completely convert the polysilicon into (poly) silicon oxide. Disclosed also is a method of forming an isolation trench in a semiconductor substrate having a high integrity oxide sidewall. After forming the trench in the substrate surface using a suitable etch mask and RIE, a single (thermal) oxide or dual (thermal) oxide and (CVD) nitride liner is formed on all trench surfaces. A conformal layer of undoped polysilicon is then formed (by. e.g. LPCVD) on the liner. By subjecting to thermal oxidation, the polysilicon is completely converted into a conformal (poly) silicon oxide layer having a thickness about 2.5 times that of the polysilicon layer. The resulting (poly) silicon oxide has the conformality of CVD oxide and the high etch resistance of thermally grown oxide. Alternatively, prior to forming the (poly) silicon oxide, the polysilicon layer is removed from the trench floor and the substrate surface in order to limit volume expansion of the polysilicon to a single direction perpendicular to the trench walls. The trench is filled with oxide, epitaxial silicon, polysilicon, polymers or metal, as desired. For achieving substrate contact through the trench, the trench bottom is opened up by RIE. Polysilicon is deposited with in-situ doping at a high temperature to fill the trench and simultaneously diffuse the dopant from the polysilicon fill into the underlying substrate to form a channel stop.