Disclosed herein are chlorodisazanes; silicon-heteroatom compounds synthesized therefrom; devices containing the silicon-heteroatom compounds; methods of making the chlorodisilazanes, the silicon-heteroatom compounds, and the devices; and uses of the chlorodisilazanes, silicon-heteroatom compounds, and devices.

Disclosed herein are chlorodisazanes; silicon-heteroatom compounds synthesized therefrom; devices containing the silicon-heteroatom compounds; methods of making the chlorodisilazanes, the silicon-heteroatom compounds, and the devices; and uses of the chlorodisilazanes, silicon-heteroatom compounds, and devices.

A method and chemical delivery system are provided for low temperature atomic layer deposition. Thus, methods of forming nitrogen-containing thin films by atomic layer deposition using a substantially water free hydrazine gas and plasma treatment are provided.

A method and chemical delivery system are provided for low temperature atomic layer deposition. Thus, methods of forming nitrogen-containing thin films by atomic layer deposition using a substantially water free hydrazine gas and plasma treatment are provided.

Provided is a method for preparing silicon nitride powder for manufacturing a substrate. The method for preparing silicon nitride powder for manufacturing a substrate, according to an embodiment of the present invention, comprises the steps of: preparing mixed raw material powder comprising metallic silicon powder and crystalline phase control powder; preparing the mixed raw material powder into granules having a predetermined particle size; nitrifying the granules at a predetermined temperature ranging from 1,200-1,500? C. while nitrogen gas is applied to the granules at a predetermined pressure; and pulverizing the nitrified granules. According to the method, it is easy to realize powder having an ? crystal phase at a desired level, and when this is realized as a substrate, a substrate having compact density can be manufactured.

Methods, systems, and components suitable for carbothermal reduction processes are disclosed. Exemplary systems include a reactor, such as hybrid solarthermal-electric reactor, a solar thermal reactor, an electric reactor, or a reactor heated by gas combustion, a pellet source, a gas reactant source, and a vacuum source. The reactor can operate as a moving bed or pseudo moving bed reactor.

A silicon nitride powder having a specific surface area of 4.0 to 9.0 m.sup.2/g, a phase proportion of less than 40 mass %, and an oxygen content of 0.20 to 0.95 mass %, wherein a frequency distribution curve obtained by measuring a volume-based particle size distribution by a laser diffraction scattering method has two peaks, peak tops of the peaks are present respectively at 0.4 to 0.7 m and 1.5 to 3.0 m, a ratio of frequencies of the peak tops ((frequency of the peak top in a particle diameter range of 0.4 to 0.7 m)/(frequency of the peak top in a particle diameter range of 1.5 to 3.0 m)) is 0.5 to 1.5, and a ratio D50/D.sub.BET (m/m) of a median diameter D50 (m) determined by the measurement of particle size distribution to a specific surface area-equivalent diameter D.sub.BET (m) calculated from the specific surface area is 3.5 or more.

A silicon nitride powder having a specific surface area of 4.0 to 9.0 m.sup.2/g, a phase proportion of less than 40 mass %, and an oxygen content of 0.20 to 0.95 mass %, wherein a frequency distribution curve obtained by measuring a volume-based particle size distribution by a laser diffraction scattering method has two peaks, peak tops of the peaks are present respectively at 0.4 to 0.7 m and 1.5 to 3.0 m, a ratio of frequencies of the peak tops ((frequency of the peak top in a particle diameter range of 0.4 to 0.7 m)/(frequency of the peak top in a particle diameter range of 1.5 to 3.0 m)) is 0.5 to 1.5, and a ratio D50/D.sub.BET (m/m) of a median diameter D50 (m) determined by the measurement of particle size distribution to a specific surface area-equivalent diameter D.sub.BET (m) calculated from the specific surface area is 3.5 or more.

Provided are a method for producing a ceramic sintered body having improved light emission intensity, a ceramic sintered body, and a light emitting device. The method for producing a ceramic sintered body comprises preparing a molded body that contains a nitride fluorescent material having a composition containing: at least one alkaline earth metal element M.sup.1 selected from the group consisting of Ba, Sr, Ca, and Mg; at least one metal element M.sup.2 selected from the group consisting of Eu, Ce, Tb, and Mn; Si; and N, wherein a total molar ratio of the alkaline earth metal element M.sup.1 and the metal element M.sup.2 in 1 mol of the composition is 2, a molar ratio of the metal element M.sup.2 is a product of 2 and a parameter y and wherein y is in a range of 0.001 or more and less than 0.5, a molar ratio of Si is 5, and a molar ratio of N is 8, and wherein the nitride fluorescent material has a crystallite size, as calculated by X-ray diffraction measurement using the Halder-Wagner method, of 550 ? or less, and calcining the molded body at a temperature in a range of 1,600? C. or more and 2,200? C. or less to obtain a sintered body.

A method of etching is described. The method includes providing a substrate having a first material containing silicon nitride and a second material that is different from the first material, forming a first chemical mixture by plasma-excitation of a first process gas containing H and optionally a noble gas, and exposing the first material on the substrate to the first chemical mixture. Thereafter, the method includes forming a second chemical mixture by plasma-excitation of a second process gas containing N, F, O, and optionally a noble element, and exposing the first material on the substrate to the second plasma-excited process gas to selectively etch the first material relative to the second material.