Patterned recess formation using acid diffusion

摘要

The present invention relates to a method for providing patterned recess formation in a previously recessed area of a semiconductor structure, i.e. DRAM trench capacitor, using acid diffusion to selectively activate some, but not all of the acid sensitive material that is filled within the recessed areas of such structures. By employing the method of the present invention, it is possible to recess all the previously recessed areas at the same time providing the same level of recessed acid sensitive material within the previous recessed areas, recess some of the previously recessed areas to a desired level leaving other portions of the structure unrecessed, or recessing the previously recessed areas to contain different levels of the acid sensitive material.