Abstract: A method for reducing curvature of a wafer having a semiconductor surface. One or more process steps are identified at which wafers exhibit the largest curvature, and/or wafer curvature that may reduce die yield. A crystal damaging process converts at least a portion of the semiconductor surface into at least one amorphous surface region After or contemporaneously with the crystal damaging, the amorphous surface region is recrystallized by recrystallization annealing that anneals the wafer for a time ?5 seconds at a temperature sufficient for recrystallization of the amorphous surface region. A subsequent photolithography step is facilitated due to the reduction in average wafer curvature provided by the recrystallization.

Abstract: A method for controlling the flatness of a wafer between lithography pattern levels. A first lithography step is performed on a topside semiconductor surface of the wafer. Reference curvature information is obtained for the wafer. The reference curvature is other than planar. At least one process step is performed that results in a changed curvature relative to the reference curvature. The changed curvature information is obtained for the wafer. Stress on a bottomside surface of the wafer is modified that reduces a difference between the changed curvature and the reference curvature. A second lithography step is performed on the topside semiconductor surface while the modified stress distribution is present.

Abstract: A method for reducing curvature of a wafer having a semiconductor surface. One or more process steps are identified at which wafers exhibit the largest curvature, and/or wafer curvature that may reduce die yield. A crystal damaging process converts at least a portion of the semiconductor surface into at least one amorphous surface region After or contemporaneously with the crystal damaging, the amorphous surface region is recrystallized by recrystallization annealing that anneals the wafer for a time ?5 seconds at a temperature sufficient for recrystallization of the amorphous surface region. A subsequent photolithography step is facilitated due to the reduction in average wafer curvature provided by the recrystallization.

Abstract: A method for controlling the flatness of a wafer between lithography pattern levels. A first lithography step is performed on a topside semiconductor surface of the wafer. Reference curvature information is obtained for the wafer. The reference curvature is other than planar. At least one process step is performed that results in a changed curvature relative to the reference curvature. The changed curvature information is obtained for the wafer. Stress on a bottomside surface of the wafer is modified that reduces a difference between the changed curvature and the reference curvature. A second lithography step is performed on the topside semiconductor surface while the modified stress distribution is present.

Abstract: An STI field oxide element in an IC which includes a layer of epitaxial semiconductor on sidewalls of the STI trench to increase the width of the active area adjacent to the STI trench and decrease a width of dielectric material in the STI trench is disclosed. STI etch residue is removed from the STI trench surface prior to growth of the epitaxial layer. The epitaxial semiconductor composition is matched to the composition of the adjacent active area. The epitaxial semiconductor may be undoped or doped to match the active area. The STI trench with the epitaxial layer is compatible with common STI passivation and fill processes. The thickness of the as-grown epitaxial semiconductor layer is selected to provide a desired active area width or a desired STI dielectric width.

Abstract: A method of forming reduced width STI field oxide elements using sidewall spacers on the isolation hardmask to reduce the STI trench width is disclosed. The isolation sidewall spacers are formed by depositing a conformal layer of spacer material on the isolation hardmask and performing an anisotropic etch. The isolation sidewall spacers reduce the exposed substrate width during the subsequent STI trench etch process, leading to a reduced STI trench width. A method of forming the isolation sidewall spacers of a material that is easily removed from the isolation hardmask to provide an exposed shoulder width on the substrate defined by the sidewall thickness is also disclosed.