C30B30/04

Semiconductor device, silicon wafer and method of manufacturing a silicon wafer

A method of manufacturing a silicon wafer is provided that includes extracting an n-type silicon ingot over an extraction time period from the a silicon melt comprising n-type dopants; adding p-type dopants to the silicon melt over at least part of the extraction time period, thereby compensating an n-type doping in the n-type silicon ingot by 10% to 80%; slicing the silicon ingot; forming hydrogen related donors in the silicon wafer by irradiating the silicon wafer with protons; and annealing the silicon wafer subsequent to the forming of the hydrogen related donors in the silicon wafer.

Modular space tether

A tether for joining objects in space by centripetal force has a modular architecture. The modular architecture facilitates the deployment of the tether by facilitating its transport into space as unassembled modular components and its assembly in situ, after the components have been transported. The modular architecture also facilitates it repair, modification, and disassembly in situ. More particularly, the modular tether has design features that enable its assembly, repair, modification, and/or disassembly in situ while the modular tether remains under tension, i.e., while the modular tether continues to perform its function of joining two or more objects by the application of centripetal force. The modular architecture also enables new tether modalities, e.g., a tensile strength modality, a winch modality, a tension monitoring modality, a repair state modality, a situational awareness modality, and a temperature control modality.

Modular space tether

A tether for joining objects in space by centripetal force has a modular architecture. The modular architecture facilitates the deployment of the tether by facilitating its transport into space as unassembled modular components and its assembly in situ, after the components have been transported. The modular architecture also facilitates it repair, modification, and disassembly in situ. More particularly, the modular tether has design features that enable its assembly, repair, modification, and/or disassembly in situ while the modular tether remains under tension, i.e., while the modular tether continues to perform its function of joining two or more objects by the application of centripetal force. The modular architecture also enables new tether modalities, e.g., a tensile strength modality, a winch modality, a tension monitoring modality, a repair state modality, a situational awareness modality, and a temperature control modality.

EPITAXIAL SILICON WAFER
20200020817 · 2020-01-16 · ·

A method of manufacturing an epitaxial silicon wafer that includes growing a silicon single crystal ingot doped with a boron concentration of 2.710.sup.17 atoms/cm.sup.3 or more and 1.310.sup.19 atoms/cm.sup.3 or less by the CZ method; producing a silicon substrate by processing the silicon single crystal ingot; and forming an epitaxial layer on a surface of the silicon substrate. During growing of the silicon single crystal ingot, the pull-up conditions of the silicon single crystal ingot are controlled so that the boron concentration Y (atoms/cm.sup.3) and an initial oxygen concentration X (10.sup.17 atoms/cm.sup.3) satisfy the expression X4.310.sup.19Y+16.3.

Method of estimating convection pattern of silicon melt, method of estimating oxygen concentration of silicon single crystal, method of manufacturing silicon single crystal, and raising device of silicon single crystal

A convection pattern estimation method of a silicon melt includes: applying a horizontal magnetic field of 0.2 tesla or more to a silicon melt in a rotating quartz crucible with use of a pair of magnetic bodies disposed across the quartz crucible; before a seed crystal is dipped into the silicon melt to which the horizontal magnetic field is applied; measuring temperatures at a first and second measurement points positioned on a first imaginary line that passes through a center of a surface of the silicon melt and is not in parallel with a central magnetic field line of the horizontal magnetic field as viewed vertically from above; and estimating a direction of a convection flow in a plane in the silicon melt orthogonal to the direction in which the horizontal magnetic field is applied on a basis of the measured temperatures of the first and second measurement points.

Method of estimating convection pattern of silicon melt, method of estimating oxygen concentration of silicon single crystal, method of manufacturing silicon single crystal, and raising device of silicon single crystal

A convection pattern estimation method of a silicon melt includes: applying a horizontal magnetic field of 0.2 tesla or more to a silicon melt in a rotating quartz crucible with use of a pair of magnetic bodies disposed across the quartz crucible; before a seed crystal is dipped into the silicon melt to which the horizontal magnetic field is applied; measuring temperatures at a first and second measurement points positioned on a first imaginary line that passes through a center of a surface of the silicon melt and is not in parallel with a central magnetic field line of the horizontal magnetic field as viewed vertically from above; and estimating a direction of a convection flow in a plane in the silicon melt orthogonal to the direction in which the horizontal magnetic field is applied on a basis of the measured temperatures of the first and second measurement points.

Methods for producing low oxygen silicon ingots

An method for producing a silicon ingot includes melting polycrystalline silicon in a crucible enclosed in a vacuum chamber to form a melt, generating a cusped magnetic field within the vacuum chamber, dipping a seed crystal into the melt, withdrawing the seed crystal from the melt to pull a single crystal that forms the silicon ingot, wherein the silicon ingot has a diameter greater than about 150 millimeters (mm), and simultaneously regulating a plurality of process parameters such that the silicon ingot has an oxygen concentration less than about 5 parts per million atoms (ppma). The plurality of process parameters include a wall temperature of the crucible, a transport of silicon monoxide (SiO) from the crucible to the single crystal, and an evaporation rate of SiO from the melt.

Methods for producing low oxygen silicon ingots

An method for producing a silicon ingot includes melting polycrystalline silicon in a crucible enclosed in a vacuum chamber to form a melt, generating a cusped magnetic field within the vacuum chamber, dipping a seed crystal into the melt, withdrawing the seed crystal from the melt to pull a single crystal that forms the silicon ingot, wherein the silicon ingot has a diameter greater than about 150 millimeters (mm), and simultaneously regulating a plurality of process parameters such that the silicon ingot has an oxygen concentration less than about 5 parts per million atoms (ppma). The plurality of process parameters include a wall temperature of the crucible, a transport of silicon monoxide (SiO) from the crucible to the single crystal, and an evaporation rate of SiO from the melt.

PERMANENT MAGNET AND METHOD OF MAKING PERMANENT MAGNET
20190385789 · 2019-12-19 ·

A method includes mixing first and second alloys to form a mixture, pressing the mixture within a first magnetic field to form a magnet having anisotropic particles of the first alloy aligned with a magnetic moment of the magnet, and heat treating the magnet within a second magnetic field to form elongated grains from the second alloy and align the elongated grains with the moment.

PERMANENT MAGNET AND METHOD OF MAKING PERMANENT MAGNET
20190385789 · 2019-12-19 ·

A method includes mixing first and second alloys to form a mixture, pressing the mixture within a first magnetic field to form a magnet having anisotropic particles of the first alloy aligned with a magnetic moment of the magnet, and heat treating the magnet within a second magnetic field to form elongated grains from the second alloy and align the elongated grains with the moment.