IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Applied Surface Analysis Tuesday Sessions
       Session AS-TuA

Paper AS-TuA3
Low Energy Ion-surface Interactions in Ultrashallow Profiling Investigated with In-situ Medium Energy Ion Scattering Spectroscopy

Tuesday, October 30, 2001, 2:40 pm, Room 134

Session: Depth Profiling I
Presenter: D.W. Moon, Korea Research Institute of Standards and Science
Authors: D.W. Moon, Korea Research Institute of Standards and Science
H.I. Lee, Korea Research Institute of Standards and Science
H.J. Kang, Chungbuk National University, Korea
Correspondent: Click to Email
For ultrashallow junction profiling with secondary ion mass spectrometry (SIMS), low energy ions have been used successfully. However, detailed understanding on the low energy ion-surface interactions have been lacking for quantitative ultrashallow junction SIMS profiling. Especially the transient surface sputtering effect in the pre-equilibrium region is one of the important phenomena to be understood. In this report, low energy ion-surface interactions are studied with in-situ medium energy ion scattering spectroscopy (MEIS) which provide quantitative composition and structural information with better than 1nm depth resolution. Damage profiles in Si(100) surfaces due to 100~500 eV O@sub 2@@super+@ ion bombardment were measured with in-situ MEIS as a function of dose, energy, and angle. The thickness of the damaged layer can be decreased down to 1nm with 80° grazing incidence. The transient sputtering yield change of an amorphous Si layer on a Si(100) could be measured quantitatively as a function of the ion dose for normal incident 500 eV O@sub 2@@super+@ ion bombardment. At the initial stage of 500 eV O@sub 2@@super+@ ion bombardment before the surface oxidation, the sputtering yield of Si was 1.4 (Si atoms/O@sub 2@@super+@). With sputtering, the Si sputtering yield decreased rapidly down to 0.06 (Si atoms/O@sub 2@@super+@) at the ion dose of 3x10@super 16@ O@sub 2@@super+@ cm@sub -2@. An initial Si surface swelling was observed due to the higher oxygen incorporation rate than the Si sputtering rate. Transient sputtering yield decrease of Si due to 500eV Ar@super +@ is also observed, in contrary.