Growth of Semiconductor Single Crystals from Vapor Phase

Abstract

Growth of single crystals from the vapor phase is considered to be an important method to obtain stoichiometric crystalline materials from inexpensive and readily available raw materials. Elements or compounds which are relatively volatile can be grown from vapor phase. Most II–VI, I–III–VI2, and III–N compounds are high-melting-point materials which may be grown as single crystals by careful use of vapor phase. The chemical vapor transport (CVT) method has been widely used as an advantageous method to grow single crystals of different compounds at temperatures lower than their melting points. This method is quite useful for the growth of II–VI and I–III–VI2 compounds, which generally have high melting point and large dissociation pressure at the melting point. In addition, they undergo solid-state phase transition during cooling or heating processes, which makes the growth of these compounds by some other methods, such as from the melt, difficult. In addition, the low growth temperature involved reduces defects produced by thermal strain, pollution from the crucible, and the cost of the growth equipment. II–VI compound semiconductors cover a very broad range of electronic and optical properties due to the large range of their energy gaps. These materials in the form of bulk single crystals or thin films are used in light emitters, detectors, linear and nonlinear optical devices, semiconductor electronics, and other devices. The development of growth technology for II–VI compound semiconductors from the vapor phase with the necessary theoretical background is important. I–III–VI2 chalcopyrite compounds are of technological interest since they show promise for application in areas of visible and infrared light-emitting diodes, infrared detectors, optical parametric oscillators, upconverters, far-infrared generation, and solar energy conversion.