Boron Trichloride Gas Research Articles

Boron-Silicon Thin Film Formation Using a Slim Vertical Chemical Vapor Deposition Reactor

A boron-silicon film was formed from boron trichloride gas and dichlorosilane gas at about 900℃ in ambient hydrogen at atmospheric pressure utilizing a slim vertical cold wall chemical vapor deposition reactor designed for the Minimal Fab system. The gas flow rates were 80, 20 and 0.1 - 20 sccm for the hydrogen, dichlorosilane and boron trichloride gases, respectively. The gas transport condition in the reactor was shown to quickly become stable when evaluated by quartz crystal microbalances at the inlet and outlet. The boron-silicon thin film was formed by achieving the various boron concentrations of 0.16% - 80%, the depth profile of which was flat. By observing the cross-sectional TEM image, the obtained film was dense. The boron trichloride gas is expected to be useful for the quick fabrication of various materials containing boron at significantly low and high concentrations.

Deposition and etching behaviour of boron trichloride gas at silicon surface

The deposition and etching at a silicon surface by boron trichloride gas were overviewed in a wide temperature range using a chemical vapour deposition reactor. At temperatures lower than 800 °C, while the silicon surface was covered with boron, the formed film thickness was ignorable. At 900 °C, the boron deposition rate increased to 0.25 μm min−1. In the temperature range between 900 and 1000 °C, the boron film formation was considerable. In contrast, at 1100 °C, the silicon surface was etched at 0.36 μm min−1. At temperatures higher than 1050 °C, while etching occurred along with producing chlorosilanes, the silicon surface after the etching was still covered with boron. Boron deposition and silicon etching might simultaneously occur at high temperatures by the boron trichloride gas. By adjusting the surface temperature to 800 °C, boron and silicon co-deposition was possible using the gas mixture of dichlorosilane and boron trichloride.

In‐situ observation of chemical vapor deposition using SiHCl3 and BCl3 gases

AbstractThe lowest temperature for initiating the film deposition was evaluated by in situ monitoring using a highly sensitive langasite crystal microbalance (LCM) in order to produce a thin boron doped silicon film using trichlorosilane gas and boron trichloride gas at low temperatures. The thin films of silicon, boron and boron‐doped silicon were individually formed from the trichlorosilane gas, boron trichloride gas and their gas mixture, respectively, on the LCM. The silicon film deposition occurred between 570 and 600 °C, while the boron film deposition occurred between 470 and 530 °C. The film deposition from both gases occurred at temperatures higher than 530 °C. Based on secondary ion mass spectrometry measurements, the boron‐doped silicon film was determined to be formed on the silicon substrate at 570 °C. Thus, the LCM could be useful for developing a thin film formation process including that for doping. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Low Energy Ion Impact-enhanced Growth of Cubic Boron Nitride in a Supersonic Nitrogen/argon Plasma Flow

This paper describes the growth and analysis of cubic boron nitride films in a low-density, supersonic nitrogen/argon plasma flow into which boron trichloride gas was injected. Both hexagonal boron nitride (h-BN) and cubic boron nitride (c-BN) were synthesized using this apparatus. Phase selectivity is obtained by applying a relatively low negative bias voltage to the substrate. All of the films described in this paper were grown on {100} silicon wafers at substrate temperatures varying from 400–700 °C. Boron nitride films with greater than 90% cubic phase were successfully synthesized with this method. The films were analyzed using infrared spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy. The volumetric percentages of the hexagonal and cubic phases were determined from model fits to the infrared transmission spectra of the films. X-ray photoelectron spectroscopy provided qualitative evidence for the presence and/or lack of sp2 bonding through the identification of a π-plasmon feature in the spectra. Infrared reflectance spectra are used to provide insight into the growth mechanisms leading to c-BN formation and have revealed features which are not present in the transmission spectra, specifically the 1305 cm−1 LO mode of c-BN and the 1610 cm−1 LO mode of h-BN. The mean ion energies involved with this bias-enhanced chemical vapor deposition (CVD) process are much lower than the ion energies in traditional physical vapor deposition (PVD) processes; however, the ion fluxes (currents) used in this CVD process are at least an order of magnitude higher, resulting in a total momentum transfer to the deposited atoms through ion bombardment that is at least equal to or greater than that reported for many ion-enhanced PVD processes.