Wafertech, Inc.

Ganesh Yerubandi

Daniel Piper

Franklin Chiang

Pang Leen Ong

Arjun Gupta

Provided is a split-gate embedded flash memory cell and method for forming the same. The flash memory cell includes split-gate transistors in which the control gate is aligned with respect to the floating gate without the use of a photolithographic patterning operation to pattern the material from which the control gates are formed. An anisotropic blanket etching operation is used to form the floating gates of the split-gate floating gate transistors alongside sidewalls of a sacrificial layer. Local oxidation of silicon (LOCOS) methods are not needed to form the inter-gate dielectric and therefore high integrity is maintained for the floating transistor gates. The floating transistor gates are formed of charge storage material such as silicon nitride, SiNin some embodiments.

Split gate embedded flash memory and method for forming the same

A shallow trench isolation (STI) structure includes a top surface formed completely of silicon nitride. The top surface of the STI structure is coplanar with a top substrate surface or extends above the top substrate surface. The STI structures include further dielectric materials beneath the silicon nitride and an oxide liner and any portions that extend above the substrate surface are formed of silicon nitride.

Nitride shallow trench isolation (STI) structures

A shallow trench isolation (STI) structure and methods for forming the same provide an STI structure with a top surface formed completely of silicon nitride. The methods for forming the STI structures provide for at least one nitride deposition step followed by a further nitride deposition step to re-fill divots that occur along the upper portions of the trench sidewalls.

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Vancouver, WA, United States of America

Ganesh Yerubandi