Loading patent…
AssigneeShin-Etsu Handotai Co., Ltd.
InventorsIzumi Fusegawa, Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta
Estimating the term…
In a method manufacturing a silicon single crystal 8 according to an MCZ method, a flow rate of an inert gas flowing in a growth furnace 1 during growth of the silicon single crystal 8 and/or a pressure in the growth furnace 1 is altered according to a pulling amount of the silicon single crystal 8 to adjust an interstitial oxygen concentration therein. By altering a flow rate of an inert gas flowing in the growth furnace or a pressure therein, an amount of oxygen evaporating as an oxide from a surface of a silicon melt 10 in the vicinity of a crystal growth interface can be easily adjusted, and thereby, an oxygen amount included in the silicon melt 10 can be controlled with ease.
A manufacturing method for a silicon single crystal from a silicon melt contained in a crucible in a silicon single crystal growth furnace by a CZ method in which not only is a MCZ method (a magnetic field applied pulling method) performing single crystal pulling under application of a magnetic field adopted, but also a flow rate of an inert gas flowing in the growth furnace during growth of the silicon single crystal and/or a pressure in the growth furnace is altered according to a pulling amount of the silicon single crystal to adjust an interstitial oxygen concentration therein.
A silicon single crystal of 200 mm or more in diameter grown using a CZ method pulling the single crystal from a silicon melt having a variation in interstitial oxygen concentration at a center of a crystal growth axis along a crystal growth axis direction confined within ±0.2×1017 atoms/cm3 of the average thereof.
Dependencies are inferred from the claim text.