A silicon single crystal manufacturing method in which the distance between the heat shield and the melt level of the melt can be regulated in a high precision. The real image includes at least the circular opening of the heat shield provided in such a way that the heat shield covers a part of the melt level of the silicon melt. The mirror image is a reflected image of the heat shield on the surface of the silicon melt. Based on the distance between the obtained real image and the mirror image, the melt level position of the silicon melt is computed, and the distance between the heat shield and the melt level position is regulated.

A method for calculating a height position of a silicon melt surface at the time of pulling a CZ silicon single crystal is disclosed, including: obtaining a first crystal diameter measured from a fusion ring on a boundary of the silicon melt and the silicon single crystal by using a CCD camera installed at an arbitrary angle relative to the silicon single crystal, and a second crystal diameter measured by using two CCD cameras installed parallel to both ends of a crystal diameter of the silicon single crystal; and calculating the height position of the silicon melt surface in the crucible during pulling of the silicon single crystal from a difference between the first crystal diameter and the second crystal diameter. As a result, a method for enabling further accurately calculating a height position of a silicon melt surface at the time of pulling a silicon single crystal is provided.

The distance between the heat shield and the melt level of the melt can be regulated in a high precision. The real image includes at least the circular opening of the heat shield provided in such a way that the heat shield covers a part of the melt level of the silicon melt. The mirror image is a reflected image of the heat shield on the surface of the silicon melt. Based on the distance between the obtained real image and the mirror image, the melt level position of the silicon melt is computed, and the distance between the heat shield and the melt level position is regulated.

The present disclosure provides a device and method for growing a crystal. A crystal preparation device includes a growth chamber, a heating component, and a filter component. The heating component includes at least one heating unit. The at least one heating unit is located in the growth chamber. The at least one heating unit is an inverted cone structure. An angle between a side surface of the inverted cone structure and an upper surface of the inverted cone structure is within a range of 5-45. The filter component is located in the growth chamber. An inner sidewall of the filter component is connected with the at least one heating unit. A gas phase channel is formed between an outer sidewall of the filter component and an inner sidewall of the growth chamber.

A method for minimizing unwanted ancillary reactions in a vacuum furnace used to process a material, such as growing a crystal. The process is conducted in a furnace chamber environment in which helium is admitted to the furnace chamber at a flow rate to flush out impurities and at a predetermined pressure to achieve thermal stability in a heat zone, to minimize heat flow variations and to minimize temperature gradients in the heat zone. During cooldown helium pressure is used to reduce thermal gradients in order to increase cooldown rates.