Abstract: In a regeneration method of the present invention, a member, to the surface of which silicon or the like adheres, is subjected to a heat treatment for at least two hours in an inert gas atmosphere at a pressure of 2.67 kPa or less so that the surface of the member is at a temperature at which SiOx and/or silicon metal adhering to the surface starts to sublimate or higher but less than a temperature at which the member starts thermal deformation and/or thermal alteration, thereby removing silicon or the like adhering to the surface of the member by means of sublimation.

Abstract: This invention provides a single-crystal manufacturing device which can perform the lifting of single crystals at a high speed, allowing single crystals with uniform qualities along their axes can be obtained.The method for manufacturing single crystals according to this invention are achieved by using a single-crystal manufacturing device provided with a combination of a heat shield plate 1 and an after-cooler 21. The heat shield plate 1, the thickness of the lower portion of which is 2-6 times that of a conventional heat shield plate, surrounds the single crystal 7 being lifted. The after-cooler 21 covers the top surface of the rim 1a of the heat shield plate 1 and encompasses the single crystal 7 being lifted. The amount of cooling water supplied to the after-cooler 21 is slowly increased until the time the single crystal is lifted to a preset length, and then the amount of cooling water is kept constant.

Abstract: An apparatus and a method for fabricating a single-crystal semiconductor by means of CZ method are provided for improving the quality control through the modification of thermal cycle of a pulled single-crystal semiconductor. The apparatus includes a ring after heater which is capable of elevation. The method decreases a temperature gradient to smaller than 20.degree. C./cm, and preferably under 15.degree. C./cm, when the pulled single-crystal semiconductor is cooled from 1200.degree. C. to 1000.degree. C. The after heater therefore heats the single-crystal semiconductor where there is a temperature of 100-300.degree. C. lower than the range of 1200-1000.degree. C. A thermal shelter is provided to retain a temperature gradient of larger than 20.degree. C./cm when the single-crystal semiconductor is within the temperature range between the melting point and 1250.degree. C. The after heater and the shelter can be raised to an upper portion when polysilicon blocks are charged and a twisting step is carried out.

Abstract: An apparatus and a method for fabricating a single-crystal semiconductor by means of a CZ method are provided for improving the quality through modification of the thermal cycle of a pulled single-crystal semiconductor. The apparatus includes a ring-shaped after heater which is capable of elevation. The method decreases the temperature gradient to smaller than 20.degree. C./cm, and preferably under 15.degree. C./cm, when the pulled single-crystal semiconductor is cooled from 1200.degree. C. to 1000.degree. C. The after heater therefore heats the single-crystal semiconductor where there is a temperature of 100.degree.-300.degree. C. lower than the range of 1200.degree.-1000.degree. C. A thermal baffle (or shield) is provided to retain a temperature gradient of larger than 20.degree. C./cm when the single-crystal semiconductor is within the temperature range between the melting point and 1250.degree. C.

Abstract: In the manufacture of a single crystal using a semiconductor single-crystal pulling apparatus equipped with a radiation screen, the time of passage of the single crystal through the high-temperature region of 1050.degree. C. and above is made to be long and the time of passage of the single crystal through the temperature region of about 900.degree. C.-500.degree. C. is made to be short. The semiconductor single-crystal pulling apparatus is so constructed that a radiation screen comprises an upper screen of 3-layer construction consisting of a heat-insulating member made of graphite or ceramics fiber clad with outer members made of graphite and a lower screen 3 of single-layer construction made of graphite, quartz or fine ceramics. Radiant heat from the molten liquid heats the lower part of single crystal as it passes through lower screen, thereby prolonging its period of passage through the high-temperature region.