US Patent 7371604 Method of forming a contact structure

Contact structures having I shapes and L shapes, and methods of fabricating I-shaped and L-shaped contact structures, are employed in semiconductor devices and, in certain instances, phase-change nonvolatile memory devices. The I-shaped and L-shaped contact structures produced by these methods exhibit relatively small active areas. The methods that determine the contact structure dimensions employ conventional semiconductor deposit and etch processing steps that are capable of creating readily reproducible results.