Single Czochralski method

TJItrahigh (99.999 + %) purity tellurium is prepared by zone refining in a hydrogen or inert-gas atmosphere. Single crystals of tellurium, tellurium alloys, and metal teUurides are grown by the Bridgman and Czochralski methods (see Semiconductors). 

The Czochralski Method has remained the most frequently employed method for obtaining single crystals. The seemingly formidable complexities involved have been conquered by the use of computer-control of the crystal-growing Parameters. One such system, available commercially, is shown in 6.4.12. (on the next page). 

Fig. 10. Pulling of a single crystal of UNi from the levitated melt by the Czochralski method...

Figure 2.1. Various forms exhibited by crystals, (a) Polyhedral crystals (b) hopper crystal (c) dendritic crystal (snow crystal, photographed by the late T. Kobayashi) (d) step pattern observed on a hematite crystal (0001) face (e) internal texture of a single crystal (diamond-cut stone, X-ray topograph taken by T.Yasuda) (f) synthetic single crystal boule. Si grown by the Czochralski method (g) synthetic corundum grown by the Verneuil method.

Lithium tantalate is a single-crystal material that is produced in quantity by the Czochralski method (see Section 3.11) for piezoelectric applications and is therefore readily available. It is stable in a hard vacuum to temperatures that allow outgassing procedures. It is insensitive to humidity. It is widely used where precise measurements are to be made. 

Strontium barium niobate is a single-crystal material with the tungsten bronze type of structure which is made by the Czochralski method but has yet to find a major use. It has relaxor characteristics of the type shown in Fig. 7.1 which give it a high pyroelectric coefficient and detectivity, but its high permittivity lowers the figure of merit l. ... 

A very important industrial crystallization process, which is the most common method used for the production of high-purity oriented single-crystalline semiconductor ingots, is the Czochralski method (Czochralski, 1918), named... 

To prepare single-crystal silicon ingots suitable for use as materials in semiconductors, the Czochralski method is used [8]. Polycrystalline silicon is melted in a crucible at 1400-1500°C under an argon atmosphere. Tiny... 

Single crystal Si formation by Czochralski method or zone refining... 

Single crystal silicon is one of the important fundamental materials for the modern photovoltaic industry. The Czochralski method of growing single crystal silicon is affected by the thermocapillary convection. Temperature and concentration gradients at the free surface of the melt give rise to surface tension-driven Marangoni flow, which can lead to crystal defects, if it is sufficiently large. 

Starting materials with alumina contents near the stoichiometry of 2 1 mullite may be completely melted above 1,960°C and then cooled to about 1,890°C without crystallizing. At the latter temperature (in the shifted solid solution region), infrared-transparent mullite single crystals could be grown by the Czochralski method [32],... 

Whereas the Czochralski method requires rather elaborate equipment to obtain single crystals of good quality, the Bridgeman (Stockbarger) method uses a fairly simple apparatus. This is shown in the following diagram ... 

Nd-doped CLNGG single crystals and ceramics have been studied and compared [174]. Single crystals of RE -doped CLNGG (RE = Nd, Yb) were grown by using the Czochralski method with Tmeit of 1548 °C) from the congruent melt... 

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