“zone refining”的概念、定义、翻译、参考文献-科学参考

zone refining

Physics

A technique used to reduce the level of impurities in certain metals, alloys, semiconductors, and other materials. It is based on the observation that the solubility of an impurity may be different in the liquid and solid phases of a material. To take advantage of this observation, a narrow molten zone is moved along the length of a specimen of the material, with the result that the impurities are segregated at one end of the bar and the pure material at the other. In general, if the impurities lower the melting point of the material they are moved in the same direction as the molten zone moves, and vice versa.

Chemistry

A technique used to reduce the level of impurities in certain metals, alloys, semiconductors, and other materials. It is based on the observation that the solubility of an impurity may be different in the liquid and solid phases of a material. To take advantage of this observation, a narrow molten zone is moved along the length of a specimen of the material, with the result that the impurities are segregated at one end of the bar and the pure material at the other. In general, if the impurities lower the melting point of the material they are moved in the same direction as the molten zone moves, and vice versa.

Chemical Engineering

A process used to reduce the impurities in certain metals, alloys, and semiconductors. It relies on the solubility of an impurity being different in the liquid and solid phases. The process involves a narrow molten zone being progressively moved along (p. 421) the length of a specimen of the material such that the impurities are segregated at one end of the ingot and pure material at the other. Where the impurities have a lower melting point than the material being purified, the impurities travel with the moving zone, and vice versa.

Zone refining was developed by American materials scientist William Gardner Pfann (1917–82) as a method of preparing high-purity materials for the manufacture of transistors. Its early use was for purifying germanium, but it can be extended to any solute–solvent system having an appreciable concentration difference between the solid and liquid phases at equilibrium. It is also known as the float zone process used in semi-conductor materials processing.

Electronics and Electrical Engineering

A method of redistributing impurities within a solid material, such as a semiconductor, by melting parts of the material and causing the molten zones to move along the sample. Impurities travel along the sample in a direction determined by their effect on the freezing point of the material. If the impurity depresses the freezing point it will travel in the same direction as the molten zone; if it raises the freezing point it will travel in the opposite direction. Zone levelling is the use of zone refining in order to distribute impurities evenly throughout the bulk of the material. Zone purification is the application of zone refining in order to reduce the concentration of an impurity in a material.
In zone refining the sample of the material is moved slowly past a heater so that the molten zone effectively moves along the length of the bar. Melting is achieved by induction heating, electron bombardment, or the heating effect of a current through a resistance coil. Zone purification carried out using a large number of heaters can reduce the impurity concentration to about one part in 10¹⁰.

Geology and Earth Sciences

1. In metallurgy, the small-scale production of high-purity metals using the principle that an impure melt will deposit pure crystals on solidifying. A rod of the specimen is melted over a very narrow region at one end, and then the molten region is transferred along the rod by means of a moving furnace. Impurities collect in the molten zone and are swept to one end of the metal.
2. In geology, the same mechanism has been invoked whereby incompatible trace elements are partitioned into an advancing partial melt.

单词	zone refining
释义	zone refining Physics A technique used to reduce the level of impurities in certain metals, alloys, semiconductors, and other materials. It is based on the observation that the solubility of an impurity may be different in the liquid and solid phases of a material. To take advantage of this observation, a narrow molten zone is moved along the length of a specimen of the material, with the result that the impurities are segregated at one end of the bar and the pure material at the other. In general, if the impurities lower the melting point of the material they are moved in the same direction as the molten zone moves, and vice versa. Chemistry A technique used to reduce the level of impurities in certain metals, alloys, semiconductors, and other materials. It is based on the observation that the solubility of an impurity may be different in the liquid and solid phases of a material. To take advantage of this observation, a narrow molten zone is moved along the length of a specimen of the material, with the result that the impurities are segregated at one end of the bar and the pure material at the other. In general, if the impurities lower the melting point of the material they are moved in the same direction as the molten zone moves, and vice versa. Chemical Engineering A process used to reduce the impurities in certain metals, alloys, and semiconductors. It relies on the solubility of an impurity being different in the liquid and solid phases. The process involves a narrow molten zone being progressively moved along (p. 421) the length of a specimen of the material such that the impurities are segregated at one end of the ingot and pure material at the other. Where the impurities have a lower melting point than the material being purified, the impurities travel with the moving zone, and vice versa. Zone refining was developed by American materials scientist William Gardner Pfann (1917–82) as a method of preparing high-purity materials for the manufacture of transistors. Its early use was for purifying germanium, but it can be extended to any solute–solvent system having an appreciable concentration difference between the solid and liquid phases at equilibrium. It is also known as the float zone process used in semi-conductor materials processing. Electronics and Electrical Engineering A method of redistributing impurities within a solid material, such as a semiconductor, by melting parts of the material and causing the molten zones to move along the sample. Impurities travel along the sample in a direction determined by their effect on the freezing point of the material. If the impurity depresses the freezing point it will travel in the same direction as the molten zone; if it raises the freezing point it will travel in the opposite direction. Zone levelling is the use of zone refining in order to distribute impurities evenly throughout the bulk of the material. Zone purification is the application of zone refining in order to reduce the concentration of an impurity in a material. In zone refining the sample of the material is moved slowly past a heater so that the molten zone effectively moves along the length of the bar. Melting is achieved by induction heating, electron bombardment, or the heating effect of a current through a resistance coil. Zone purification carried out using a large number of heaters can reduce the impurity concentration to about one part in 10¹⁰. Geology and Earth Sciences 1. In metallurgy, the small-scale production of high-purity metals using the principle that an impure melt will deposit pure crystals on solidifying. A rod of the specimen is melted over a very narrow region at one end, and then the molten region is transferred along the rod by means of a moving furnace. Impurities collect in the molten zone and are swept to one end of the metal. 2. In geology, the same mechanism has been invoked whereby incompatible trace elements are partitioned into an advancing partial melt.
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