Reactive sticking coefficients (RSCs) were measured for silane and disilane on polycrystalline silicon for a wide range of temperature and flux (pressure) conditions. The data were obtained from deposition-rate measurements using molecular beam scattering and a very low-pressure cold-wall reactor. The RSCs have nonlinear Arrhenius temperature dependencies and decrease with increasing flux at low (710 °C) temperatures. Several simple models are proposed to explain these observations. The results are compared with previous studies of the SiH4/Si(s) reaction and low-pressure chemical vapor deposition-rate measurements.

Articles you may be interested inStudy of surface reactions during plasma enhanced chemical vapor deposition of SiO2 from SiH4, O2, and Ar plasma J.

Production of an atomic oxygen beam by a nozzlebeamtype microwave radical source Rev. Sci. Instrum. 66, 4166 (1995); 10.1063/1.1145365 Supersonic nozzle beam source of atomic oxygen produced by electric discharge heating Rev. Sci. Instrum. 53, 1714 (1982); 10.1063/1.1136875 Supersonic atomic and molecular halogen nozzle beam source Rev. Sci. Instrum. 48, 58 (1977);A high pressure, radio frequency discharge nozzle beam source has been developed for the production of very intense (~10 18 atoms sr-I S-I) supersonic beams of oxygen atoms. An efficient impedance matching scheme has been devised for coupling the radio frequency power to oxygen-rare gas mixtures as a function of gas pressure, temperature, and composition. Techniques for localizing the discharge directly behind the orifice of a specially designed quartz nozzle have also been developed. The above combine to yield a beam source which reliably produces a high degree of molecular dissociation in oxygen-rare gas mixtures at pressures up to 350 Torr. Atomic oxygen mean translational energies from 0.14--0.50 eV have been achieved using the seeded beams technique with Mach numbers up to 10 being realized. When helium is used as the carrier gas both OCP J ) and OCD 2 ) atoms are present in the beam, while only ground state atoms appear to be present in argon seeded mixtures. This paper describes the design, construction, and operation of this beam source and provides a characterization of the atomic oxygen beams it has reproducibly generated in our laboratory.

Formaldehyde photopredissociation was studied under collisionless conditions by the technique of crossed laser and molecular beams. Detection of the molecular product co after excitation of H2CO near the s1 origin gives strong support to the sequential coupling model for fast nonradiative decay of S1 states through broadened s 0 levels to the continuum. For H2CO excitation at 283.9 nm, formation of the radical product HCO dominates dissociation to molecular products by at least one order of magnitude.