|
90 Atomistic simulations of Ar+-ion-assisted etching of silicon by fluorine and chlorine
Author(s): D. Humbird (Affiliation: Lam Res., Fremont, CA, USA ), D.B. Graves
Journal: J. Vac. Sci. Technol. A, Vac. Surf. Films (USA), vol.23, no.1, p.31-8 (Jan. 2005)
Publisher: AIP for American Vacuum Soc, USA
Language: English
ISSN: 0734-2101, Full text
Document type: Journal article
Abstract: We present simulations of Si etching with F and Cl radicals in the presence of inert ion bombardment. Si etch yields predicted by the simulation are in good agreement with experiments. The atomic-scale mechanisms of ion-enhanced etching are classified as enhanced spontaneous etching, chemically enhanced physical sputtering, and chemical sputtering. The primary effects of ions are to increase the local surface coverage of etchant species by increasing the sticking coefficient of arriving radicals and by mediating diffusion of etchant into the subsurface during impact, and create volatile products by inducing chemical reactions within the halogenated surface layer. Ion-assisted effects are most pronounced at low neutral-to-ion ratio and decline as this ratio increases. Explicit ion enhancements to the etch yield are greater for Cl than for F (29 refs.)
Inspec No.: 8248335
91 Preparation and characterization of atomically clean, stoichiometric surfaces of AIN(0001)
Author(s): W.J. Mecouch, B.P. Wagner, Z.J. Reitmeier, R.F. Davis (Affiliation: Dept. of Mater. Sci. & Eng., North Carolina State Univ., Raleigh, NC, USA), C. Pandarinath, B.J. Rodriguez, R.J. Nemanich
Journal: J. Vac. Sci. Technol. A, Vac. Surf. Films (USA), vol.23, no.1, p.72-7 (Jan. 2005)
Publisher: AIP for American Vacuum Soc, USA
Language: English
ISSN: 0734-2101, Full text
Document type: Journal article
Abstract: In situ exposure of the (0001) surface of AlN thin films to flowing ammonia at 1120°C and 10-4 Torr removes oxygen/hydroxide and hydrocarbon species below the detectable limits of x-ray photoelectron spectroscopy and decreases the Al/N ratio from 1.3 to 1.0. The positions of the Al 2p and the N 1s core level peaks acquired from the cleaned surfaces were 75.0±0.1 eV and 398.2±0.1 eV, respectively, which were similar to the values determined for the as-loaded samples. The cleaning process left unchanged the (1×1) low energy electron diffraction pattern, the step-and-terrace microstructure, and the root mean square roughness values observed for the surfaces of the as-loaded samples; i.e., the surface structure and microstructure were not changed by the high-temperature exposure to ammonia at low pressures. Vacuum annealing under 10-7 Torr at 1175°C for 15 min removed all detectable hydrocarbons; however, it did not remove the oxygen/hydroxide species (11 refs.)
Inspec No.: 8248341
92 Feature-scale model of Si etching in SF6 plasma and comparison with experiments
Author(s): R.J. Belen, S. Gomez (Affiliation: Dept. of Chem. Eng., Univ. of California, Santa Barbara, CA, USA), M. Kiehlbauch, D. Cooperberg, E.S. Aydil
Journal: J. Vac. Sci. Technol. A, Vac. Surf. Films (USA), vol.23, no.1, p.99-113 (Jan. 2005)
Publisher: AIP for American Vacuum Soc, USA
Language: English
ISSN: 0734-2101, Full text
Document type: Journal article
Abstract: We have developed a semiempirical feature scale model of Si etching in SF6 plasma, which incorporates the addition of small amounts of O in the discharge coming from the etching of the oxide mask and quartz window. The degrees of freedom in the model are reduced by using information from plasma diagnostics and previously published data to estimate the ion flux, the ion energy and angle distributions, and the relative F and O fluxes. Experimentally inaccessible parameters such as the F sticking coefficient, chemical etch rate constant, and the ion-enhanced etch yield are determined by matching simulated feature profiles with those obtained from carefully designed etching experiments. Excellent agreement between experiments and simulations is obtained (41 refs.)
Inspec No.: 8248345
93 Si-SiO2 interface passivation using hydrogen and deuterium implantation
Author(s): T. Kundu, D. Misra (Affiliation: Dept. of Electr. & Comput. Eng., New Jersey Inst. of Technol., Newark, NJ, USA)
Journal: Electrochem. Solid-State Lett. (USA), vol.8, no.2, p. G35-7 (Feb. 2005)
Publisher: Electrochem. Soc, USA
Language: English
ISSN: 1099-0062, Full text
Document type: Journal article
Abstract: Hydrogen/deuterium was implanted in <100> silicon to passivate dangling bonds at the Si/SiO2 interface when a thin oxide is grown on implanted silicon substrate. It was observed that implantation energy and dose influence the interface passivation. Measured interface states at the Si/SiO2 interface suggest an isotope effect where deuterium implanted devices yielded better interface passivation compared to that of hydrogen implanted devices. Diffusion of implanted hydrogen and deuterium to the interface is affected by the implantation damage (17 refs.)
Inspec No.: 8249231
|
