Abstract: A system controls the diameter of both a neck region and a full diameter region of a monocrystalline rod being pulled from molten material held in a crucible. The system uses a video camera viewing light reflected from a meniscus around the rod where the rod emerges from a melt surface of the molten material. The video camera has a zoom lens for enlarging an image of the meniscus during growth of the neck of the rod and for reducing an image of the meniscus during growth of a full diameter body of the rod. A computer controlling a pull rate for the neck growth of the rod is rapidly responsive to a count of total camera pixels illuminated by the image of the meniscus during neck growth.

Abstract: An apparatus for controllably feeding a particulate material, and particularly silicon material into a crucible, comprises a drum mounted for rotation about an axis tilted at an acute angle with reference to the horizontal. At least one cavity, a portion of which is formed in the inner surface of the bottom wall of the drum, extends from about the outer periphery of the bottom wall at its one end towards the center thereof at its other end. At one of its ends, the cavity communicates with an aperture in the bottom wall. A feeding tube having an outlet port supplies the material into the cavity and is so positioned in relation to the drum that the outlet port directs the material into the cavity only when the cavity is in a rotational position in which its end with the aperture is elevated with respect to a horizontal plane above the other end of the same cavity and pours the material into that portion of the receiving cavity which is remote from the aperture.

Abstract: A crystal growing furnace has lift and rotation control apparatus for both a growing crystal and a crucible containing a melt. A transducer and a servo motor are disposed above the furnace having respective shafts connected along a common horizontal axis on opposite sides of a longitudinal light tube wherein the light tube and transducer shaft can be axially positioned by the shaft of the servo motor. The light tube has a lens for focusing at times on a spot on a meniscus in the furnace and at times on the melt, a light sense detector is connected to the light tube for at times generating a servo motor control error signal to drive the servo motor incrementally to an angular position corresponding to growth in the diameter of the meniscus by tracking a spot on the meniscus. The transducer generates an output signal indicative of incremental angular movement in response to growing the crystal for governing the lift and rotation control apparatus.

Abstract: A crystal growing furnace has lift and rotation control apparatus for both a growing crystal and a crucible containing a melt. A transducer and a servo motor are disposed above the furnace having respective shafts connected along a common horizontal axis on opposite sides of a longitudinal light tube wherein the light tube and transducer shaft can be axially positioned by the shaft of the servo motor. The light tube has a lens for focusing at times on a spot on a meniscus in the furnace and at times on the melt, a light sense detector is connected to the light tube for at times generating a servo motor control error signal to drive the servo motor incrementally to an angular position corresponding to growth in the diameter of the meniscus by tracking a spot on the meniscus. The transducer generates an output signal indicative of incremental angular movement in response to growing the crystal for governing the lift and rotation control apparatus.

Abstract: A novel electronic timing apparatus is described which contains means for selecting a preset time interval and means for selecting an actual interval to be timed which is equal to or less than, and also a function of, the preset interval. When the apparatus begins timing an actual interval, a first energy source is activated and a second energy source is deactivated. When timing of the actual interval is completed, the first energy source is deactivated and the second energy source is activated. The appartus is powered by a power supply means which furnishes a regulated direct current to integrated circuits requiring such and furnishes line frequency current to other circuits. It also contains means for generating and shaping periodic pulses from line frequency current to form an electronic time base signal for its operation.