Patent ID: 6486682
Filing Date: 2002-11-26
Classification: H01L

Abstract:
A method for determining a first dielectric constant, e1, for a first dielectric material and a second dielectric constant, e2, for a second dielectric material forming a MOS (metal oxide semiconductor) stack, the method including the steps of:A. forming a first test MOS (metal oxide semiconductor) stack having a first total effective oxide thickness, EOTA, and being comprised of: a first interfacial structure comprised of said second dielectric material having said second dielectric constant, e2, and having a first interfacial thickness T2A, wherein said first interfacial structure is disposed on a semiconductor substrate; and a first high-K structure comprised of said first dielectric material having said first dielectric constant, e1, and having a first high-K thickness, T1A, wherein said first high-K structure is disposed between said first interfacial structure and a first conductive structure; B. forming a second test MOS (metal oxide semiconductor) stack having a second total effective oxide thickness, EOTB, and being comprised of: a second interfacial structure comprised of said second dielectric material having said second dielectric constant, e2, and having a second interfacial thickness T2B, wherein said second interfacial structure is disposed on said semiconductor substrate; and a second high-K structure comprised of said first dielectric material having said first dielectric constant, e1, and having a second high-K thickness T1B, wherein said second high-K structure is disposed between said second interfacial structure and a second conductive structure; C. measuring said first total effective oxide thickness, EOTA, of said first test MOS stack and measuring said second total effective oxide thickness, EOTB, of said second test MOS stack; D. measuring said first interfacial thickness, T2A, of said first interfacial structure and measuring said first high-K thickness, T1A, of said first high-K structure; E. measuring said second interfacial thickness, T2B, of said second interfacial structure and measuring said second high-K thickness, T1B, of said second high-K structure; and F. determining said first dielectric constant, e1, and said second dielectric constant, e2, depending on relations between values of EOTA, T1A, and T2A, and between values of EOTB, T1B, and T2B.