Methods for fabricating memory cells having fin structures with semicircular top surfaces and rounded top corners and edges

摘要

Methods for fabricating a FIN structure with a semicircular top surface and rounded top surface corners and edges are disclosed. As a part of a disclosed method, a FIN structure is formed in a semiconductor substrate. The FIN structure includes a top surface having corners and edges. The FIN structure is annealed where the annealing causes the top surface to have a semicircular shape and the top surface corners and edges to be rounded.

主权项

1. A method for forming a FIN structure with semicircular top surface and rounded top surface corners and edges, comprising:
forming a FIN structure in a semiconductor substrate wherein said FIN structure includes a top surface having corners and edges; and annealing said FIN structure to effect an initiation and completion of rounding for said method of said top surface corners and edges in a single annealing operation free of any preceding, intermediate and subsequent rounding operations that round said top surface corners and edges in part wherein said single annealing operation causes the top surface area between said corners and edges to have a semicircular shape along the entire surface between anterior and posterior portions of said FIN in a direction orthogonal to the direction between said edges wherein said annealing comprises initially performing a dilute hydrofluoric acid (DHF) clean, and subsequently performing simultaneously both an ammonia/peroxide mix (APM) clean and hydrochloric/peroxide mix (HPM) clean to form native oxide and a H2 anneal.