Shallow trench isolation technology to eliminate a kink effect

Abstract

A process for creating an insulator filled, shallow trench, in a semiconductor substrate, in which the insulator layer in the shallow trench, is not exposed to procedures used to remove defining composite insulator layers, has been developed. The process features creating a lateral recess, in a thick silicon nitride layer, used as a component of a composite insulator layer, where the composite insulator layer is used for subsequent definition of the shallow trench, in the semiconductor substrate. An insulator deposition, filling openings, and recesses, in the composite insulator layer, and filling the shallow trench, followed by removal of excess insulator fill, on the top surface of the composite insulator layer, results in the formation of a 'T' shape insulator, comprised of an insulator shape, in the shallow trench, and comprised of a wider insulator shape, located in the composite insulator shape, with the lateral recess in the thick silicon nitride layer, and with the wider insulator shape, overlying the narrow, insulator shape, in the shallow trench. The insulator, in the shallow trench, is protected from the procedure used to remove components of the composite insulator layer, by the wider insulator shape.