Atomic Layer Deposition (ALD)Presentation OverviewDefinition of ALDSlide 4Slide 5Slide 6Brief History of ALDSlide 8ALD Process and EquipmentsSlide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23ALD ApplicationsSlide 25Slide 26Slide 27Summary1Atomic Layer Deposition (ALD)Presented byPresented byMyo Min TheinMyo Min TheinEE 518 Class Presentation, Penn StateEE 518 Class Presentation, Penn StateSpring 2006Spring 2006Instructor: Dr. J. RuzylloInstructor: Dr. J. Ruzyllo4/25/06 EE 518 Class Presentation 2Presentation OverviewPresentation Overview•Definition of ALDDefinition of ALD•Brief history of ALDBrief history of ALD•ALD process and equipmentsALD process and equipments•ALD applicationsALD applications•SummarySummary4/25/06 EE 518 Class Presentation 3Definition of ALDDefinition of ALD•ALD is a method of applying thin ALD is a method of applying thin films to various substrates with films to various substrates with atomic scale precision.atomic scale precision.•Similar in chemistry to chemical vapor deposition (CVD), Similar in chemistry to chemical vapor deposition (CVD), except that the ALD reaction breaks the CVD reaction except that the ALD reaction breaks the CVD reaction into two half-reactions, keeping the precursor materials into two half-reactions, keeping the precursor materials separate during the reaction.separate during the reaction.•ALD film growth is self-limited and based on surface ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale reactions, which makes achieving atomic scale deposition control possible.deposition control possible.•By keeping the precursors separate throughout the By keeping the precursors separate throughout the coating process, atomic layer thickness control of film coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular grown can be obtained as fine as atomic/molecular scale per monolayer.scale per monolayer.Ref:Ref: "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. <http://en.http://en.wikipediawikipedia.org/.org/wikiwiki/Atomic_Layer_Deposition/Atomic_Layer_Deposition>.>.4/25/06 EE 518 Class Presentation 4Definition of ALDDefinition of ALD•ALD is a method of applying thin films to various ALD is a method of applying thin films to various substrates with atomic scale precision.substrates with atomic scale precision.•Similar in chemistry to CVD, except Similar in chemistry to CVD, except that the ALD reaction breaks the that the ALD reaction breaks the CVD reaction into two half-reactions, CVD reaction into two half-reactions, keeping the precursor materials keeping the precursor materials separate during the reaction.separate during the reaction.•ALD film growth is self-limited and based on surface ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale deposition reactions, which makes achieving atomic scale deposition control possible.control possible.•By keeping the precursors separate throughout the By keeping the precursors separate throughout the coating process, atomic layer thickness control of film coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale grown can be obtained as fine as atomic/molecular scale per monolayer.per monolayer.Ref:Ref: "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. <http://en.http://en.wikipediawikipedia.org/.org/wikiwiki/Atomic_Layer_Deposition/Atomic_Layer_Deposition>.>.4/25/06 EE 518 Class Presentation 5•ALD is a method of applying thin films to various ALD is a method of applying thin films to various substrates with atomic scale precision.substrates with atomic scale precision.•Similar in chemistry to chemical vapor deposition (CVD), Similar in chemistry to chemical vapor deposition (CVD), except that the ALD reaction breaks the CVD reaction except that the ALD reaction breaks the CVD reaction into two half-reactions, keeping the precursor materials into two half-reactions, keeping the precursor materials separate during the reaction.separate during the reaction.•ALD film growth is ALD film growth is self-limited and based on surface reactions, which makes achieving atomic which makes achieving atomic scale deposition control possible.scale deposition control possible.•By keeping the precursors separate throughout the By keeping the precursors separate throughout the coating process, atomic layer thickness control of film coating process, atomic layer thickness control of film grown can be obtained as fine as atomic/molecular scale grown can be obtained as fine as atomic/molecular scale per monolayer.per monolayer.Definition of ALDDefinition of ALDRef:Ref: "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. < "Atomic Layer Deposition," Wikipedia: The Free Encyclopedia, Wikimedia Foundation, 24 April 06. <http://en.http://en.wikipediawikipedia.org/.org/wikiwiki/Atomic_Layer_Deposition/Atomic_Layer_Deposition>.>.4/25/06 EE 518 Class Presentation 6Definition of ALDDefinition of ALD•ALD is a method of applying thin films to various ALD is a method of applying thin films to various substrates with atomic scale precision.substrates with atomic scale precision.•Similar in chemistry to chemical vapor deposition (CVD), Similar in chemistry to chemical vapor deposition (CVD), except that the ALD reaction breaks the CVD reaction except that the ALD reaction breaks the CVD reaction into two half-reactions, keeping the precursor materials into two half-reactions, keeping the precursor materials separate during the reaction.separate during the reaction.•ALD film growth is self-limited and based on surface ALD film growth is self-limited and based on surface reactions, which makes achieving atomic scale reactions, which makes achieving atomic scale deposition control possible.deposition control possible.•By keeping the precursors separate By keeping the precursors separate throughout the coating process, throughout the coating process, atomic layer thickness control of film atomic layer