Seh America, Inc.

Aaron L LaBrie

Kenneth C Ivey

Aaron W Johnson

Masahiko Baba

Randall Spradlin

A crystal pulling apparatus is disclosed which employs the Czochralski method. The crystal pulling apparatus is operated while a containing a crucible of molten material, while maintaining the growing chamber under a controlled pressure of less than atmospheric. In the event of a vacuum pump unexpectedly ceasing operation, power to the heater is terminated, thus allowing the molten material to solidify. In such an event, a second vacuum pump can readily be attached to the growing chamber thus restoring pressure control, and allowing power to the heater to be restored.

Auxillary vacuum apparatus and method for crystal growth

A high pressure gas cleaning purge cleaning silicon oxide dust deposits from inside a dry vacuum pump while installed on a crystal grower. The high pressure gas cleaning purge is performed before or after each crystal is grown. The high pressure gas flow is injected into the inlet of the dry vacuum pump and repeatedly turned on and off to create differing turbulent flow patterns within the pump. The differing turbulent flow patterns effectively remove substantial quantities of the silicon oxide dust deposited in the pump during crystal growing.

High pressure gas cleaning purge of a dry process vacuum pump

A high pressure gas cleaning purge cleans silicon oxide dust deposits from inside a dry vacuum pump while installed on a crystal grower. The high pressure gas cleaning purge is performed before or after each crystal is grown. The high pressure gas flow is injected into the inlet of the dry vacuum pump and repeatedly turned on and off to create differing turbulent flow patterns within the pump. The differing turbulent flow patterns effectively remove substantial quantities of the silicon oxide dust deposited in the pump during crystal growing.

An apparatus for weighing single crystals during Czochralski crystal growing processes includes a pivotal elongated member such as a beam, a contact element and a load sensor. The load sensor can be mounted to at least one of the elongated member and a support surface of a crystal growing vessel. The beam is attached to a lift for pulling single crystals from a melt. During crystal growing, the weight of the grown crystal causes increased loading along the elongated member such that the contact element exerts an increasing force on the load sensor. The contact element and load sensor have respective contact surfaces which are shaped such that the force exerted on the load sensor corresponds substantially to the weight of grown single crystal. Typically, at least one of the contact surfaces is a rolling surface.

Apparatus for weighing crystals during Czochralski crystal growing

A method and apparatus for measuring and controlling the diameter of a silicon single crystal ingot grown by the Czochralski technique using dual optical cameras focused on diametrically opposed edges of the meniscus of the growing crystal to measure the actual crystal diameter. The crystal growth parameters can be adjusted in response to the measured diameter to maintain a constant, desired diameter. The method and apparatus of the invention provide a continuous accurate measurement of the crystal diameter and avoid unnecessary adjustments to the crystal growth conditions resulting from diameter measurement errors due to the effects of crystal orbit, melt level changes and camera angle variations.

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Vancouver, WA, United States of America

Aaron L LaBrie