Low-energy hydrogen ion bombardment damage in silicon: An in situ optical investigation

Journal Article · Tue Sep 01 04:00:00 EDT 1987 · J. Vac. Sci. Technol., A; (United States)

DOI:https://doi.org/10.1116/1.574310· OSTI ID:6296766

Collins, R W; Cavese, J M

In situ and spectroscopic ellipsometry measurements have been applied to probe damage mechanisms induced by low-energy hydrogen ion bombardment of single-crystal silicon. Ion beam voltages from 20 to 1500 V have been employed, covering the range found to passivate grain boundaries in polycrystalline Si and near-surface defects in dry etched single-crystal Si. The spectroscopic data for room-temperature samples after bombardment provide information needed to model the in situ data, obtained using a fixed photon energy of 3.4 eV at a nominal sample temperature of 200 C. Models for the in situ ellipsometry data for ion energies <500 V allow determination of the evolution of damaged surface layers as a function of exposure time. Two layers dominate the time evolution of the optical data: (1) a polycrystalline Si (p-Si)-like layer, modeled as an effective medium mixture of c-Si, a-Si, and void, which develops on the scale of 1 min (dose: 6 x 10 X ions/cmS), and (2) a more slowly evolving transparent layer, interpreted as an oxide. The latter layer, also observed in earlier studies, may be attributed to oxidation caused by vacuum residual oxygen ions in the hydrogen ion beam. The oxidation consumes the top-most p-Si-like region of heaviest damage.

• Research Organization: Standard Oil Research and Development, Cleveland, Ohio 44128
• OSTI ID: 6296766
• Journal Information: J. Vac. Sci. Technol., A; (United States), Journal Name: J. Vac. Sci. Technol., A; (United States) Vol. 5:5; ISSN JVTAD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605* -- Materials-- Radiation Effects
CHARGED PARTICLES
CHEMICAL REACTIONS
COLLISIONS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DAMAGE
ELEMENTS
ELLIPSOMETRY
ENERGY RANGE
EV RANGE
GRAIN BOUNDARIES
HYDROGEN IONS
ION COLLISIONS
IONS
KEV RANGE
KEV RANGE 01-10
LAYERS
MEASURING METHODS
MICROSTRUCTURE
OXIDATION
PASSIVATION
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
SEMIMETALS
SILICON
SPECTRA
SPECTROSCOPY
VISIBLE SPECTRA