The present invention relates to highly polarizable 3D organic perovskites of the general formula ABX.sub.3, prepared by introducing halogen functional groups in the A-site cation (in which the A and B sites are occupied by organic cations and the X site is a monovalent non-metallic counterion). The (DCl)(NH.sub.4)(BF.sub.4).sub.3 crystal exhibits a strong linear electrooptic (EO) effect with an effective EO coefficient of 20 pmV.sup.−1, which is 10 times higher than that of metal halide perovskites. These 3D organic perovskites are solution processed and compatible with silicon, and illustrate the potential of rationally-designed all-organic perovskites for use in on-chip modulators, electro-optic devices, piezoelectric devices, or silicon photonics devices.

There is provided a method of producing boron trichloride, in which boron trichloride with high purity can be produced in simple production steps, and blockage of a production line is inhibited. The method of producing boron trichloride includes: a metal chlorination step of bringing a gas containing chlorine gas into contact with raw boron carbide as boron carbide including, as an impurity, a metal other than boron, and allowing the metal to react with the chlorine gas in the gas containing the chlorine gas, to form a metal chloride and to obtain boron carbide containing the metal chloride; a removal step of removing the metal chloride from the boron carbide containing the metal chloride, obtained in the metal chlorination step; and a generation step of bringing a gas containing chlorine gas into contact with the boron carbide from which the metal chloride has been removed in the removal step, and allowing the boron carbide and the chlorine gas in the gas containing the chlorine gas to react with each other to generate boron trichloride.

There is provided a method of producing boron trichloride, in which damage to a reaction container is inhibited. The method of producing boron trichloride includes performing reaction between chlorine gas in a gas containing the chlorine gas and particulate boron carbide (4) in a state in which the boron carbide (4) flows in the gas containing the chlorine gas.

A hydrogenated isotopically enriched boron trifluoride (BF3) dopant source gas composition. The composition contains (i) boron trifluoride isotopically enriched above natural abundance in boron of atomic mass 11 (UB), and (ii) hydrogen in an amount of from 2 to 6.99 vol. %, based on total volume of boron trifluoride and hydrogen in the composition. Also described are methods of use of such dopant source gas composition, and associated apparatus therefor.

The present invention provides a method for separation and recovery of boron trifluoride and complexes thereof in an olefin polymerization reaction. The method for separation and recovery of boron trifluoride and complexes thereof in an olefin polymerization reaction, comprising: 1) subjecting a mixture obtained after an olefin polymerization reaction to flash distillation separation to separate part of gaseous boron trifluoride; 2) subjecting the liquid phase obtained from the flash distillation separation to membrane separation to obtain complexes of boron trifluoride and a crude product of the olefin polymerization reaction; and 3) subjecting the crude product of the olefin polymerization reaction obtained in step 2) to gas stripping separation to separate the remaining gaseous boron trifluoride, so as to obtain a pure product of the olefin polymerization reaction The present invention designs a matching process based on the polymorphic characteristics of boron trifluoride and complexes thereof to achieve efficient separation of boron trifluoride and complexes thereof from polymerization intermediates.

Embodiments of the invention provide a method for atomic layer etching (ALE) of a substrate. According to one embodiment, the method includes providing a substrate, and exposing the substrate to hydrogen fluoride (HF) gas and a boron-containing gas to etch the substrate. According to another embodiment, the method includes providing a substrate containing a metal oxide film, exposing the substrate to HF gas to form a fluorinated surface layer on the metal oxide film, and exposing the substrate to a boron-containing gas to remove the fluorinated surface layer from the metal oxide film. The exposures may be repeated at least once to further etch the metal oxide film.

A compound ammonium fluoroborate, a nonlinear optical crystal of ammonium fluoroborate, and a preparation method and use thereof; the compound has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, and is prepared by a solid phase reaction process; the crystal has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, belongs to the orthorhombic system, and has a space group of Pna2.sub.1 and the following unit cell parameters: a=7.615(3) , b=11.207(4) , c=6.604(3) , Z=4, V=563.6 .sup.3. The nonlinear optical crystal can be obtained by the method of the present invention. The present invention provides uses of the nonlinear optical crystal in producing harmonic light and a deep-ultraviolet frequency-multiplied light below 200 nm; and in making a frequency multiplication generator, a frequency up or down converter or an optical parametric oscillator.

A compound ammonium fluoroborate, a nonlinear optical crystal of ammonium fluoroborate, and a preparation method and use thereof; the compound has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, and is prepared by a solid phase reaction process; the crystal has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, belongs to the orthorhombic system, and has a space group of Pna2.sub.1 and the following unit cell parameters: a=7.615(3) , b=11.207(4) , c=6.604(3) , Z=4, V=563.6 .sup.3. The nonlinear optical crystal can be obtained by the method of the present invention. The present invention provides uses of the nonlinear optical crystal in producing harmonic light and a deep-ultraviolet frequency-multiplied light below 200 nm; and in making a frequency multiplication generator, a frequency up or down converter or an optical parametric oscillator.

A compound ammonium fluoroborate, a nonlinear optical crystal of ammonium fluoroborate, and a preparation method and use thereof; the compound has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, and is prepared by a solid phase reaction process; the crystal has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, belongs to the orthorhombic system, and has a space group of Pna2.sub.1 and the following unit cell parameters: a=7.615(3) , b=11.207(4) , c=6.604(3) , Z=4, V=563.6 .sup.3. The nonlinear optical crystal can be obtained by the method of the present invention. The present invention provides uses of the nonlinear optical crystal in producing harmonic light and a deep-ultraviolet frequency-multiplied light below 200 nm; and in making a frequency multiplication generator, a frequency up or down converter or an optical parametric oscillator.

A compound ammonium fluoroborate, a nonlinear optical crystal of ammonium fluoroborate, and a preparation method and use thereof; the compound has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, and is prepared by a solid phase reaction process; the crystal has the chemical formula of NH.sub.4B.sub.4O.sub.6F with a molecular weight of 176.28, belongs to the orthorhombic system, and has a space group of Pna2.sub.1 and the following unit cell parameters: a=7.615(3) , b=11.207(4) , c=6.604(3) , Z=4, V=563.6 .sup.3. The nonlinear optical crystal can be obtained by the method of the present invention. The present invention provides uses of the nonlinear optical crystal in producing harmonic light and a deep-ultraviolet frequency-multiplied light below 200 nm; and in making a frequency multiplication generator, a frequency up or down converter or an optical parametric oscillator.