Structural studies of hydrogen-bombarded silicon using ellipsometry and transmission electron microscopy

Abstract

Hydrogen-bombardment-induced structural changes in single-crystal silicon were studied using ellipsometry and transmission electron microscopy techniques. Hydrogen ion energies ranged from 400 to 1900 eV and the total dose was about 5×1019 ions/cm2. Various degrees of damage and phase mixtures in the layers were identified. It was concluded that ellipsometry can be used effectively as a nondestructive characterizational tool for analyzing bombardment-induced microstructural changes in this material.

Helium-induced porous layer formation in Silicon.

“…We have been able to show that the similar formation of stable cavities in silicon takes place with high doses of 3 keV hydrogen implants. The result ties in with data on hydrogen irradiated silicon [20] and on laser induced defects [21] where the presence of stable defects, presumably cavities, is found at annealing temperatures higher than 675K.…”

An ellipsometric and RBS study of TiSi2 formation

“…In the first one we have optimized the thickness of a pure titanium layer on a silicon substrate. A substantial improvement is obtained once the titanium layer is allowed to contain voids reflecting the titanium microstructure [6,9]; the residue becomes 8.5 × 10 -3, which for the case of this kind of analysis becomes an acceptable fit [1][2][3][4][5]. These voids are incorporated by means of the Bruggeman effective medium theory [29][30][31].…”

“…buried oxide or nitride layers [1][2][3][4][5]. Metallic systems have the disadvantage that the dielectric functions required are not uniquely known [6][7][8][9].…”

Molecular dynamic simulation of damage formation at Si vertical walls by grazing incidence of energetic ions in gate etching processes

“…Due to the small mass and radius of a hydrogen atom compared with those of a silicon atom, damage formation of Si surfaces by energetic incident H þ ions 8,9,13 is known to be different from that by heavier incident ions such Ar þ . Earlier studies [14][15][16][17] on RIE processes by hydrogen containing plasmas recognized Si damage formed by H þ ion bombardment as a cause of lifetime degradation of metal-oxide-semiconductor capacitors. What has not been discussed so much is a possibility of Si damage formation by energetic ions at oblique angle impact.…”