Residual stresses in Mo/Si and Mo2C/Si multilayers

Conference · Thu Apr 01 04:00:00 EST 1999

OSTI ID:8583

Barbee, T W ^[1]; Nguyen, T D

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1. LLNL

The authors report a study of the residual stresses and residual stress relaxation in Mo/Si and Mo{sub 2}C/Si EUV multilayers. The multilayers were fabricated by magnetron sputter deposition, and stress measured using the substrate curvature laser scanning technique. It was found that Mo{sub 2}C/Si multilayers exhibit higher compressive stress than Mo/Si of comparable period and layer thickness ratio. the multilayers sputtered at 0.5 mT Ar pressure have higher compressive stress than those sputtered at 2 mT Ar pressure. The data indicate that the residual stresses in the multilayers are primarily determined by the Si layers. Annealing of the multilayers at a heating rate of 5 C/minute as well as at a fixed temperature (isothermal) results in a reduction of the compressive stresses. Near zero stress is achieved after annealing at 300 C. The time dependence of the residual stress decrease during isothermal annealing was found to fit best to a bimolecular viscous flow model of defect annihilation in the amorphous Si layers. The relationships between the effects of annealing on the multilayer microstructure and the observed stress reduction are discussed.

• Research Organization: Lawrence Livermore National Lab., CA (US)
• Sponsoring Organization: USDOE Office of Defense Programs (DP) (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 8583
• Report Number(s): UCRL-JC-134021
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANNEALING
HEATING RATE
MAGNETRONS
RESIDUAL STRESSES
STRESS RELAXATION
STRESSES
TIME DEPENDENCE
VISCOUS FLOW