Growing Single Crystals

Books about crystal-growing procedures are available.  

It is difficult to assess the relative merits of the different methods used for growing crystals on account of the following factors  

The choice of the shape of the crystal (cylinder, disc, thin layer) depends on the techniques which will be used. (Thin layers are necessary for resistance measurements of the surface layer during electrochemical adsorption, while some optical measurements require large surface areas.) 

An incidental advantage, which can be useful for electrochemists, is the perfect surface found on crystals grown from the vapor or from electrolytic solutions. 

What is possible for one metal might be impossible for another. 

---

In this Chapter, we intend to investigate mechanisms of particle growth. We will, in the next chapter, address the methods used to form (grow) single crystals and how they have been utilized. Certain properties of particles, including measurement of size, wiU be discussed later in this chapter. But first, we need to define exactly what we mean by a particle. 

One method we might use is to cool the melt to incipient nuclei-formatlon. toss in the seed-crystal, and allow the melt to freeze into a single crystal. This is the KYROPOULOS method which we will discuss in detail later. Alas, this method only works for a few systems, notably alkali halides (cubic) and the like. We find that we can use a seed-crystal to grow single crystals, but only if we use it under carefully defined conditions. A modified K5rropoulos method has been used for many years to form single-crystal sapphire up to 13.0 inches in dieimeter. Plates cut from such crystals are used as windows and substrates for all sorts of integrated circuits, as well as watch "crystals". 

The major components needed to grow single crystals by this method are ... 

With the introduction of this method and with further improvements in classical ways of growing single crystals, the studies on individual single-crystal faces expanded rapidly. Many hundred papers relating to such electrodes have been published since the 1970s. 

Figure Plasma reactor for growing single crystals of refractory metals, alloys and high melting point carbides.

Vemeuil A process for growing single crystals of refractory compounds. The powdered material is dropped through an oxy-hydrogen flame and the product, consisting of microscopic molten droplets, is collected on a seed crystal. As the liquid mass reaches a cooler zone it crystallizes in the form of a single crystal known as a boule. Invented by A. V. L. Vemeuil at the Museum of Natural History, Paris, who made synthetic rabies and sapphires in this way. 

Single crystals of H-aggregates were prepared from four compounds with the relation m-n=2. The crystallization of these compounds was very difficult and took several months to grow single crystals suitable for X-ray analysis. Various solvents were examined for crystallization. Among them, single crystals were obtained from the mixture of ethanol and... 

Methods Used to Grow Single Crystals of Actinide Metals... 

Considerable effort has been expended in growing single crystals of compositions in the solid solution, with particular emphasis on the superconducting composition. A variety of methods have been employed, all flux type, as the solid solution members are not congruently melting. There have been a few detailed reports on growth of single crystals from melts in the... 

---