Method to fabricate capacitor structures with very narrow features using

Abstract

A method of fabrication of a storage capacitors for DRAM memory cells using silylated photoresist is described. Partially completed DRAM memory cells comprising wordline transistor gates and bitline source and drain regions is provided. Conductive plugs are provided through a dielectric layer to the top surfaces of the bitline drain regions. A first conductive layer is deposited overlying the conductive plugs. A photoresist layer is deposited overlying the first conductive layer. The photoresist layer is etched to define the areas for the lower plates of the storage capacitors. The photoresist is exposed to a silylating agent to form a silylated layer. The top layer of the silylated photoresist is etched through to form a mask for subsequent etching. The photoresist layer is etched as defined by the mask. The first conductive layer is etched as defined by the mask to form the shape of the lower nodes of the storage capacitors. The remaining silylated photoresist is removed. A capacitor dielectric layer is deposited overlying the lower nodes of the storage capacitors. A second conductive layer is deposited to form the upper nodes of the storage capacitors. A passivation layer is deposited to complete fabrication.