A method for manufacturing a light emitting diode structure, comprising: forming an array of nanowires on a planar support (5, 501, 7 or 103), wherein each of the nanowires comprises a first conductivity type nanowire core and an enclosing second conductivity type nanowire shell for forming a pn or pin junction that in operation provides an active region for light generation, and each nanowire comprises a respective tip and respective vertical sidewalls; producing a substance at a source and causing it to move to the array along a line, wherein (i) the angle between the line followed by the substance and the plane of the support (5, 501, 7 or 103) is less than 90° when measured from the center of the support (5, 501, 7 or 103); (ii) the substance is capable of rendering a portion of the nanowires nonconductive or less conductive compared to before being treated by the substance; (iii) a non-conductive layer (503 or 602) including a non-conductive material is formed over a horizontal top surface of the planar support (5, 501, 7 or 103); and (iv) discrete portions of the non-conductive material that do not physically contact one another are formed on the tips of a first group of the nanowires; and forming a transparent conductive oxide layer directly on the vertical sidewalls of the first group of the nanowires, wherein: the non-conductive layer (503 or 602) is formed directly on the tips and vertical sidewalls of a second group of the nanowires and directly on the tips of the first group of the nanowires but not on a portion of vertical sidewalls of the first group of the nanowires, the first group of nanowires are in the interior of the nanowire array and the second group of nanowires are on the exterior edge of the nanowire array, and the array of nanowires are rotated while the substance moves to the array along the line, vertical sidewalls of the second group of nanowires on the exterior edge are coated by the non-conductive layer (503 or 602) completely, but the first group of nanowires is shadowed from the non-conductive layer deposition and vertical sidewalls of the first group of nanowires are partially coated by the non-conductive layer (503 or 602), the portions of the vertical sidewalls of the first group of nanowires that are coated by the non-conductive layer (503 or 602) being determined by the angle; and the transparent conductive oxide layer is laterally spaced from the vertical sidewalls of the second group of the nanowires by vertical portions of the non-conductive layer (503 or 602). forming an array of nanowires on a planar support (5, 501, 7 or 103), wherein each of the nanowires comprises a first conductivity type nanowire core and an enclosing second conductivity type nanowire shell for forming a pn or pin junction that in operation provides an active region for light generation, and each nanowire comprises a respective tip and respective vertical sidewalls; producing a substance at a source and causing it to move to the array along a line, (i) the angle between the line followed by the substance and the plane of the support (5, 501, 7 or 103) is less than 90° when measured from the center of the support (5, 501, 7 or 103); (ii) the substance is capable of rendering a portion of the nanowires nonconductive or less conductive compared to before being treated by the substance; (iii) a non-conductive layer (503 or 602) including a non-conductive material is formed over a horizontal top surface of the planar support (5, 501, 7 or 103); and (iv) discrete portions of the non-conductive material that do not physically contact one another are formed on the tips of a first group of the nanowires; and forming a transparent conductive oxide layer directly on the vertical sidewalls of the first group of the nanowires, the non-conductive layer (503 or 602) is formed directly on the tips and vertical sidewalls of a second group of the nanowires and directly on the tips of the first group of the nanowires but not on a portion of vertical sidewalls of the first group of the nanowires, the first group of nanowires are in the interior of the nanowire array and the second group of nanowires are on the exterior edge of the nanowire array, and the array of nanowires are rotated while the substance moves to the array along the line, vertical sidewalls of the second group of nanowires on the exterior edge are coated by the non-conductive layer (503 or 602) completely, but the first group of nanowires is shadowed from the non-conductive layer deposition and vertical sidewalls of the first group of nanowires are partially coated by the non-conductive layer (503 or 602), the portions of the vertical sidewalls of the first group of nanowires that are coated by the non-conductive layer (503 or 602) being determined by the angle; and the transparent conductive oxide layer is laterally spaced from the vertical sidewalls of the second group of the nanowires by vertical portions of the non-conductive layer (503 or 602).