NOVELTY - Method for providing texture to semiconductor surface involves providing mask of resist material (1123B) on some regions of the surface; providing etchant on exposed regions (1127B) of surface to form cavities, which undercut the mask material with leaving overhanging portions; deforming overhanging mask portions into covering proximity with portion of surface of cavities, where region of each cavity surface remains exposed; and providing treating agent to semiconductor surface such that cavity portions covered by mask resist treatment and exposed regions of cavities become treated.    USE - For selectively treating semiconductor surface by providing texture to the surface (claimed), used in solar cell.    ADVANTAGE - The method increases light absorption into silicon wafers by selectively changing reflective properties of bottom portions of light trapping features.    DETAILED DESCRIPTION - Method for providing texture to semiconductor surface involves providing mask of material on the surface, where mask material is patterned so that some regions of the surface are covered with resist material (1123B) and some are exposed; providing etchant to the surface; allowing the etchant to etch away semiconductor material at exposed regions (1127B), and form cavities in the surface, which undercut the mask material with leaving overhanging portions; deforming overhanging mask portions into covering proximity with portion of surface of cavities, where region of each cavity surface remains exposed; and providing a treating agent comprising an isotropic etchant to the semiconductor surface, such that, cavity surface portions covered by mask resist treatment and exposed regions of the cavities become treated. INDEPENDENT CLAIMS are included for the following:    (1) method of patterning surface of substrate involving providing substrate having surface cavity; and patterned mask disposed over the surface, the mask comprising an opening facing the cavity, where perimeter of cavity is greater than perimeter (1128B) of the opening, the mask is positioned relative to cavity such that an overhanging mask portion is spaced from surface of cavity; deforming the overhanging mask portion into covering proximity with portion of surface of the cavity, where region of the cavity surface remains exposed; and providing treating agent to the surface; and    (2) solar cell with semiconductor wafer (1104) having surface comprising spaced apart cavities, in which some of the cavities having bottom surface that has first region with first radius of curvature, and also within same cavity, a second region having second, smaller radius of curvature.    DESCRIPTION OF DRAWING(S) - The figure shows schematic view of wafer.    Wafer (1104)    Resist mask (1123B)    Exposed area (1127B)    Perimeter (1128B)    Ridges (1141)