초록 ▼

Methods and apparatus for manufacturing silica crucibles 9 containing few, if any, white point defects. The white point defects are reduced by decreasing the amount of silica vapor condensing on electrodes 4,5,6 used in the manufacturing process. The silica vapor condensation is decreased by providi

Methods and apparatus for manufacturing silica crucibles 9 containing few, if any, white point defects. The white point defects are reduced by decreasing the amount of silica vapor condensing on electrodes 4,5,6 used in the manufacturing process. The silica vapor condensation is decreased by providing a flow of a protective or non-reactive gas or gas mixture through protective devices 11,12,13, over portions of the electrodes where the silica vapor would otherwise condense.

대표청구항 ▼

[ We claim:] [1.] A method for making at least one silica crucible, comprising:providing a crucible substrate;providing a plurality of electrodes having an arc or plasma discharge therebetween;melting silica particles by introducing them through the arc or plasma discharge toward the crucible substr

[ We claim:] [1.] A method for making at least one silica crucible, comprising:providing a crucible substrate;providing a plurality of electrodes having an arc or plasma discharge therebetween;melting silica particles by introducing them through the arc or plasma discharge toward the crucible substrate;protecting a portion of the electrodes proximate the crucible substrate from silica vapor condensation; andcooling the crucible to its final form.