A method for ion-assisted etching a stack of alternating silicon oxide and silicon nitride layers in an etch chamber is provided. An etch gas comprising a fluorine component, helium, and a fluorohydrocarbon or hydrocarbon is flowed into the etch chamber. The gas is formed into an in-situ plasma in the etch chamber. A bias of about 10 to about 100 volts is provided to accelerate helium ions to the stack and activate a surface of the stack to form an activated surface for ion-assisted etching, wherein the in-situ plasma etches the activated surface of the stack.

A silicon nitride substrate including silicon nitride crystal grains and a grain boundary phase and having a thermal conductivity of 50 W/m.Math.K or more, wherein, in a sectional structure of the silicon nitride substrate, a ratio (T2/T1) of a total length T2 of the grain boundary phase in a thickness direction with respect to a thickness T1 of the silicon nitride substrate is 0.01 to 0.30, and a variation from a dielectric strength mean value when measured by a four-terminal method in which electrodes are brought into contact with a front and a rear surfaces of the substrate is 20% or less. The dielectric strength mean value of the silicon nitride substrate can be 15 kV/mm or more. According to above structure, there can be obtained a silicon nitride substrate and a silicon nitride circuit board using the substrate in which variation in the dielectric strength is decreased.

A silicon nitride substrate including silicon nitride crystal grains and a grain boundary phase and having a thermal conductivity of 50 W/m.Math.K or more, wherein, in a sectional structure of the silicon nitride substrate, a ratio (T2/T1) of a total length T2 of the grain boundary phase in a thickness direction with respect to a thickness T1 of the silicon nitride substrate is 0.01 to 0.30, and a variation from a dielectric strength mean value when measured by a four-terminal method in which electrodes are brought into contact with a front and a rear surfaces of the substrate is 20% or less. The dielectric strength mean value of the silicon nitride substrate can be 15 kV/mm or more. According to above structure, there can be obtained a silicon nitride substrate and a silicon nitride circuit board using the substrate in which variation in the dielectric strength is decreased.

A method for ion-assisted etching a stack of alternating silicon oxide and silicon nitride layers in an etch chamber is provided. An etch gas comprising a fluorine component, helium, and a fluorohydrocarbon or hydrocarbon is flowed into the etch chamber. The gas is formed into an in-situ plasma in the etch chamber. A bias of about 10 to about 100 volts is provided to accelerate helium ions to the stack and activate a surface of the stack to form an activated surface for ion-assisted etching, wherein the in-situ plasma etches the activated surface of the stack.

A silicon chalcogenate precursor comprising the chemical formula of Si(XR.sup.1).sub.nR.sup.2.sub.4-n, where X is sulfur, selenium, or tellurium, R.sup.1 is hydrogen, an alkyl group, a substituted alkyl group, an alkoxide group, a substituted alkoxide group, an amide group, a substituted amide group, an amine group, a substituted amine group, or a halogen group, each R.sup.2 is independently hydrogen, an alkyl group, a substituted alkyl group, an alkoxide group, a substituted alkoxide group, an amide group, a substituted amide group, an amine group, a substituted amine group, or a halogen group, and n is 1, 2, 3, or 4. Methods of forming the silicon chalcogenate precursor, methods of forming silicon nitride, and methods of forming a semiconductor structure are also disclosed.

A silicon chalcogenate precursor comprising the chemical formula of Si(XR.sup.1).sub.nR.sup.2.sub.4-n, where X is sulfur, selenium, or tellurium, R.sup.1 is hydrogen, an alkyl group, a substituted alkyl group, an alkoxide group, a substituted alkoxide group, an amide group, a substituted amide group, an amine group, a substituted amine group, or a halogen group, each R.sup.2 is independently hydrogen, an alkyl group, a substituted alkyl group, an alkoxide group, a substituted alkoxide group, an amide group, a substituted amide group, an amine group, a substituted amine group, or a halogen group, and n is 1, 2, 3, or 4. Methods of forming the silicon chalcogenate precursor, methods of forming silicon nitride, and methods of forming a semiconductor structure are also disclosed.

Provided are a novel amino-silyl amine compound and a manufacturing method of a dielectric film containing SiN bond using the same. Since the amino-silyl amine compound according to the present invention, which is a thermally stable and highly volatile compound, may be treated at room temperature and used as a liquid state compound at room temperature and pressure, the present invention provides a manufacturing method of a high purity dielectric film containing a SiN bond even at a low temperature and plasma condition by using atomic layer deposition (PEALD).

Provided are a novel amino-silyl amine compound and a manufacturing method of a dielectric film containing SiN bond using the same. Since the amino-silyl amine compound according to the present invention, which is a thermally stable and highly volatile compound, may be treated at room temperature and used as a liquid state compound at room temperature and pressure, the present invention provides a manufacturing method of a high purity dielectric film containing a SiN bond even at a low temperature and plasma condition by using atomic layer deposition (PEALD).

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.

A system for chemical transformation of 3D state materials is disclosed wherein, a reaction group having a main body arranged to shape a reaction chamber in which a component configured to support a sample of 3D state arranged to be chemically transform is expected. The system further includes an oven arranged to heat the reaction chamber and a GAS supply group arranged to release a first gas in the reaction chamber and/or a casing component, inside the main body, which has a chemical agent suitable for releasing a second gas into the reaction chamber. The main body has at least two turbines arranged to converge into the reaction chamber, the first and/or the second gas on the samples. The invention relates also to a method for chemical transformation of 3D state materials.