Patent ID: 8735296

Claim:
A method, comprising: forming a plurality of mandrels on a layer on a substrate; forming a first conformal layer on said mandrels and on a top surface of said layer; forming a second conformal layer on said first conformal layer; forming a block mask over a second less than whole portion of said plurality of mandrels; performing an isotropic etch to completely remove said second conformal layer from a first less than whole portion of said plurality of mandrels where said second conformal layer is not protected by said block mask; performing an anisotropic etch of said first and second conformal layers, said anisotropic etch forming first sidewall spacers on said first less than whole portion of said plurality mandrels, said first sidewall spacers comprise first regions of said first conformal layer and no regions of said second conformal layer and forming second sidewall spacers on said second less than whole portion of said plurality mandrels, said second sidewall spacers comprise second regions of said first conformal layer and regions of said second conformal layer on said second regions of said first conformal layer, said first and second sidewall spacers having different widths, a width of said first sidewall spacers based on a thickness of said first conformal layer on sidewalls of said first less than whole portion of said plurality of mandrels and a width of said second sidewall spacers based on a thickness of said first and second conformal layers on sidewalls of said second less than whole portion of said plurality of mandrels; removing said plurality of mandrels; and using said first and second sidewall spacers as a hardmask, simultaneously transferring the pattern formed by said first and second sidewall spacers into said layer.