The invention provides process for producing a stable Si or Ge electrode structure comprising cycling a Si or Ge nanowire electrode until a structure of the Si nanowires form a continuous porous network of Si or Ge ligaments.

A method for producing a membrane device includes: forming an insulating film as a first film on a Si substrate; forming a Si film as a second film on the entire surface or a part of the first film; forming an insulating film as a third film on the second film; forming an aperture so as to pass through a part of the third film positioned on the second film and not to pass through the second film; etching a part of the substrate on one side of the first film with a solution that does not etch the first film; and etching a part or all of the second film on the other side of the first film with a gas or a solution that does not etch the first film and has an etching rate for the third film lower than an etching rate for the second film.

A method for producing a membrane device includes: forming an insulating film as a first film on a Si substrate; forming a Si film as a second film on the entire surface or a part of the first film; forming an insulating film as a third film on the second film; forming an aperture so as to pass through a part of the third film positioned on the second film and not to pass through the second film; etching a part of the substrate on one side of the first film with a solution that does not etch the first film; and etching a part or all of the second film on the other side of the first film with a gas or a solution that does not etch the first film and has an etching rate for the third film lower than an etching rate for the second film.

A plate-shaped sample with a cross-section perpendicular to a radial direction of a polycrystalline silicon rod as a principal surface is sampled from a region from a center (r=0) of the polycrystalline silicon rod to R/3. Then, the sample is disposed at a position at which a Bragg reflection from a (111) Miller index plane is detected. In-plane rotation with a rotational angle φ on the sample is performed with a center of the sample as a rotational center such that an X-ray irradiation region defined by a slit performs φ-scanning on the principal surface of the sample to obtain a diffraction chart indicating dependency of a Bragg reflection intensity from the (111) Miller index plane on a rotational angle of the sample. A ratio (S.sub.p/S.sub.t) between an area S.sub.p of a peak part appearing in the diffraction chart and a total area S.sub.t of the diffraction chart is calculated.

A plate-shaped sample with a cross-section perpendicular to a radial direction of a polycrystalline silicon rod as a principal surface is sampled from a region from a center (r=0) of the polycrystalline silicon rod to R/3. Then, the sample is disposed at a position at which a Bragg reflection from a (111) Miller index plane is detected. In-plane rotation with a rotational angle φ on the sample is performed with a center of the sample as a rotational center such that an X-ray irradiation region defined by a slit performs φ-scanning on the principal surface of the sample to obtain a diffraction chart indicating dependency of a Bragg reflection intensity from the (111) Miller index plane on a rotational angle of the sample. A ratio (S.sub.p/S.sub.t) between an area S.sub.p of a peak part appearing in the diffraction chart and a total area S.sub.t of the diffraction chart is calculated.

A method of depositing a silicon film on a recess formed in a surface of a substrate is provided. The substrate is placed on a rotary table in a vacuum vessel, so as to pass through first, second, and third processing regions in the vacuum vessel. An interior of the vacuum vessel is set to a first temperature capable of breaking an Si—H bond. In the first processing region, Si.sub.2H.sub.6 gas having a temperature less than the first temperature is supplied to form an SiH.sub.3 molecular layer on its surface. In the second processing region, a silicon atomic layer is exposed on the surface of the substrate, by breaking the Si—H bond in the SiH.sub.3 molecular layer. In the third processing region, by anisotropic etching, the silicon atomic layer on an upper portion of an inner wall of the recess is selectively removed.

A method of depositing a silicon film on a recess formed in a surface of a substrate is provided. The substrate is placed on a rotary table in a vacuum vessel, so as to pass through first, second, and third processing regions in the vacuum vessel. An interior of the vacuum vessel is set to a first temperature capable of breaking an Si—H bond. In the first processing region, Si.sub.2H.sub.6 gas having a temperature less than the first temperature is supplied to form an SiH.sub.3 molecular layer on its surface. In the second processing region, a silicon atomic layer is exposed on the surface of the substrate, by breaking the Si—H bond in the SiH.sub.3 molecular layer. In the third processing region, by anisotropic etching, the silicon atomic layer on an upper portion of an inner wall of the recess is selectively removed.

Provided are a deposition process monitoring system capable of detecting an internal state of a chamber in a deposition process, and a method of controlling the deposition process and a method of fabricating a semiconductor device using the system. The deposition process monitoring system includes a facility cover configured to define a space for a deposition process, a chamber located in the facility cover, covered with a translucent cover dome, and having a support on which a deposition target is placed, a plurality of lamps disposed in the facility cover, the lamps respectively disposed above and below the chamber, the lamps configured to supply radiant heat energy into the chamber during the deposition process, and a laser sensor disposed outside the chamber, the laser sensor configured to irradiate the cover dome with a laser beam and detect an intensity of the laser beam transmitted through the cover dome, wherein a state of by-products with which the cover dome is coated is determined based on the detected intensity of the laser beam.

Methods of forming memory structures are discussed. Specifically, methods of forming 3D NAND devices are discussed. Some embodiments form memory structures with a metal nitride barrier layer, an α-tungsten layer, and a bulk metal material. The barrier layer comprises a TiXN or TaXN material, where X comprises a metal selected from one or more of aluminum (Al), silicon (Si), tungsten (W), lanthanum (La), yttrium (Yt), strontium (Sr), or magnesium (Mg).

The present invention decreases the impurity concentration of polycrystalline silicon to be produced. An apparatus (1) for producing polycrystalline silicon (S1) includes: a reactor (10) that contains a raw material gas (G1) for silicon deposition; a feed pipe (20) that forms a feed channel for feeding the raw material gas (G1) into the reactor (10), the feed pipe (20) including an inflow port (111) which is formed in the reactor (10) and through which the raw material gas (G1) flows in; and a filter (30) for removing impurities which have mixed in the raw material gas (G1), the filter (30) being provided in the feed channel.