Microstructural and phase stability studies of nanometer period metal/carbon multilayer structures for x-ray optics

Technical Report · Tue May 01 00:00:00 EDT 1990

OSTI ID:6949961

Nguyen, Tai D

Multilayer structures of W/C, WC/C, and Ru/C, of various periods were prepared by magnetron sputtering and studied by x-ray diffraction and high-resolution transmission electron microscopy. Studies of microstructures and phases present inside the layers, interfaces, and stability of layered structures and period, of both as-prepared and annealed samples were made. Both as-prepared and annealed WC/C multilayers are predominantly amorphous, while the phases in the W/C depend on the periods. The 2 nm period W/C multilayer remains amorphous after annealing, and the longer periods recrystallize to form W{sub 2}C. The layered structures of both W/C and WC/C systems are stable on annealing for periods equal to or larger than 2 nm, while the amorphous Ru-rich layers in the 2 nm period Ru/C multilayer agglomerate upon annealing to form elemental Ru crystallites. Annealing of 1 nm period W/C multilayer also leads to destruction of the layered structures. Longer period Ru/C multilayers show stable layered structures on annealing, and indicate elemental Ru in the Ru-rich layers. Crystalline planes extending into the amorphous layers and grain boundaries in the crystalline layers roughens the interfaces. X-ray measurements show that the multilayer periods expand on annealing for all metal/C multilayers studied. Mechanisms for this expansion is not known, although it seems to be linked to the amorphous C-rich layers. 40 refs., 42 figs., 3 tabs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• Sponsoring Organization: USDOD; DOE/ER
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6949961
• Report Number(s): LBL-29206; ON: DE90015307; CNN: F49620-87-K-0001
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON
LAYERS
MICROSTRUCTURE
RUTHENIUM
TUNGSTEN
ANNEALING
INTERFACES
PHASE STABILITY
POLISHING
TRANSMISSION ELECTRON MICROSCOPY
TUNGSTEN CARBIDES
CARBIDES
CARBON COMPOUNDS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ELEMENTS
HEAT TREATMENTS
METALS
MICROSCOPY
NONMETALS
PLATINUM METALS
REFRACTORY METAL COMPOUNDS
STABILITY
SURFACE FINISHING
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
360602* - Other Materials- Structure & Phase Studies