公开(公告)号：JP2001110751A

公开(公告)日：2001-04-20

申请号：JP2000152242

申请日：2000-05-24

Applicant: LUCENT TECHNOLOGIES INC

Inventor： BHOWMIK SIDDHARTHA ,  MERCHANT SAILESH M ,  MINSEOKU OO ,  PRADIP KUMAR ROY ,  SEN SIDHARTHA

IPC: C23C14/14 ,  C23C16/06 ,  H01L21/28 ,  H01L21/285 ,  H01L21/3205 ,  H01L21/768 ,  H01L23/52

Abstract: PROBLEM TO BE SOLVED: To provide a titanium-tantalum barrier thin film and a method for forming a thin film. SOLUTION: In a titanium-tantalum barrier thin film used together with an interconnecting thin film of copper, a relatively excessive titanium/insufficient tantalum portion is formed near the boundary between the thin film and a dielectric thin film, and a relatively excessive tantalum/insufficient titanium portion is formed near the boundary between the thin film and a conductive interconnecting thin film formed on the barrier layer. Excessive titanium/ insufficient tantalum portion causes the thin film, to firmly stick to the dielectric thin film and the excessive tantalum/insufficient titanium portion suppresses formation of an intermetallic compound by forming a hetero-epitaxial interface with the interconnecting thin film. The single titanium-tantalum thin film, having a compositional gradient from the top to the bottom, can be formed by various techniques including PVD, CVD, sputter deposition using a sputtering target having a uniform composition, and sputter deposition using a plurality of sputtering targets. A synthetic titanium-tantalum thin film is composed of two separately formed thin films.