International Business Machines Corporation

Siemens Aktiengesellschaft

Kabushiki Kaisha Toshiba

James F Moseman

Herbert Lei Ho

David M Dobuzinsky

Herbert Palm

Atul Champaklal Ajmera

Philip L Flaitz

Erwin Hammerl

Hiroshi Takato

Samuel C Ramac

Stephen G Fugardi

Seiko Yoshida

John Preston Benedict

Erwin N Hammerl

J Herbert Palm

Disclosed is an improved process and liner for trench isolation which includes either a single oxynitride layer or a dual oxynitride (or oxide)/nitride layer. Such a process and liner has an improved process window as well as being an effective O.sub.2 diffusion barrier and resistant to hot phosphoric and hydrofluoric acids.

Shallow trench isolation with oxide-nitride/oxynitride liner

Silicon integrated circuits use a crystalline layer of silicon nitride (Si.sub.3 N.sub.4) in shallow trench isolation (STI) structures as an O.sub.2 -barrier film. The crystalline Si.sub.3 N.sub.4 lowers the density of electron traps as compared with as-deposited, amorphous Si.sub.3 N.sub.4. Further, a larger range of low-pressure chemical-vapor deposited (LPCVD) Si.sub.3 N.sub.4 films can be deposited, providing a larger processing window for thickness controllability. An LPCVD-Si.sub.3 N.sub.4 film is deposited at temperatures of 720.degree. C. to 780.degree. C. The deposited film is in an amorphous state. Subsequently, a high-temperatures rapid-thermal anneal in pure nitrogen or ammonia is conducted at 1050.degree. C. to 1100.degree. for 60 seconds.

Application of thin crystalline Si.sub.3 N.sub.4 liners in shallow

Silicon integrated circuits use a crystalline layer of silicon nitride (Si.sub.3 N.sub.4) in shallow trench isolation (STI) structures as an O.sub.2 -barrier film. The crystalline Si.sub.3 N.sub.4 lowers the density of electron traps as compared with as-deposited, amorphous Si.sub.3 N.sub.4. Further, a larger range of low-pressure chemical-vapor deposited (LPCVD) Si.sub.3 N.sub.4 films can be deposited, providing a larger processing window for thickness controllability. An LPCVD-Si.sub.3 N.sub.4 film is deposited at temperatures of 720.degree. C. to 780.degree. C. The deposited film is in an amorphous state. Subsequently, a high-temperatures rapid-thermal anneal in pure nitrogen or ammonia is conducted at 1050.degree. C. to 1100.degree. C. for 60 seconds.

Application of thin crystalline Si.sub.3 N.sub.4  liners in shallow

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Glenham, NY, United States of America

James F Moseman