Atomic Layer Deposition (ALD) Presented by Myo Min Thein EE 518 Class Presentation, Penn State Spring 2006 I nstructor: Dr. J. Ruzyllo 2 Presentation Overview Definition of ALD Brief history of ALD : ALD process and equipments · ALD applications • Summary 4/25/06 EE 518 Class Presentation 3 Definition of ALD : ALD is a method of applying thin films to various substrates with atomic scale precision. Similar in chemistry to chemical vapor deposition (CvD), except that the ALD reaction breaks the CVD reaction into two half- reaction. ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale deposition control possible By keeping the precursors separate throughout the coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale per monolayer. Ref: "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < http:// en.wikipedia.org/wiki/ Atomic Layer Deposition> 4/25/06 EE 518 Class Presentation 4 Definition of ALD ALD is a method of applying thin films to various substrates with atomic scale precision. Similar in chemistry to CVD, except that the ALD reaction breaks the CVD reaction into two half-reactions, keeping the precursor materials separate during the reaction. ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale deposition control possible. By keeping the precursors separate throughout the coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale per monolayer. Ref:"Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. <http://en.wikipedia.org/wiki/ Atomic Layer Deposition> 4/25/06 EE 518 Class Presentation 5 Definition of AlD ALD is a method of applying thin films to various substrates with atomic scale precision. Similar in chemistry to chemical vapor deposition (CvD), except that the ALD reaction breaks the CVD reaction into two half. reaction. ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale deposition control possible. By keeping the precursors separate throughout the coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale per monolayer. Ref:"Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < http:// en.wikipedia.org/wiki/ Atomic Layer Deposition> 4/25/06 EE 518 Class Presentation 6 Definition of ALD ALD is a method of applying thin films to various substrates with atomic scale precision. Similar in chemistry to chemical vapor deposition (CVD), except that the ALD reaction breaks the CVD reaction into two half. reaction. ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale deposition control possible By keeping the precursors separate throughout the coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale per monolayer. Ref: "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < http://en.wikipedia.org/wiki/ Atomic Layer Deposition> 4/25/06 EE 518 Class Presentation 7 Brief History of ALD . Introduced in 1974 by Dr. Tuomo Suntola and co-workers in Finland to improve the quality of ZnS films used in electroluminescent displays. Recently, it turned out that ALD also produces outstanding dielectric layers and attracts semiconductor industries for making High-K dielectric materials. Ref: "History of Atomic Layer Deposition (ALD)," Finnish MicroNanoTechnology Network (FMNT), 24 April 2006. <http://www.fmnt.fi/index.pl?id=2913&isa=Category&op=show> 4/25/06 EE 518 Class Presentation