Preparation of Highly Pure Germanium Polycrystals
Germanium (Ge) is a chemical element which belongs to the family of semiconductors, due to its conductivity and electrical properties. It has several industrial and technological applications, mainly related to its electrical properties, which make the demand for the highest purity materials of this element considerable. Due to its physical and chemical properties, germanium is a difficult material to be purified and processed simultaneously, which makes the production of highly pure germanium polycrystalline materials a challenging task.
In recent years, the development of various processes, mainly by physical and chemical methods, has allowed obtaining a complete purification of the germanium with an increase in its quality and purity. This purification process is essential for industrial and technological purposes, where materials are highly required to have a high level of purity and properties.
Polycrystalline material of germanium (Ge) is frequently used in many areas, mainly in optoelectronics, high-performance integrated circuits, detectors, and solid-state lasers. Its production involves a number of steps, including the purification of the raw materials to remove impurities; the preparation of the precursor addition to act as a catalyst; the production of the polycrystalline material in an appropriate vessel with the necessary thermochemical conditions; and finally the extraction of highly pure germanium polycrystals.
The purification of the raw germanium can be achieved by a number of methods, such as chemical leaching, thermal decomposition, or chemical vapor-phase deposition. Once the raw material is sufficiently pure, it is then subjected to a thermal treatment in an appropriate melting furnace, which allows the homogeneous mixture of the precursor and germanium. The temperature is then brought to a certain temperature in order to allow the precipitation of the germanium crystallites in a polycrystalline form.
Once the polycrystalline material is obtained, it must be extracted in order to separate the highly pure germanium polycrystals from the precursor elements. This can be achieved by a number of methods, such as chemical leaching or thermal treatment, which allow this separation. After this, the material can be packed in hermetically sealed containers, in order to prevent any contamination, and is ready for the industrial application.
The production of highly pure germanium polycrystals is still a challenge, due to the difficulties in obtaining high purity and homogeneous polycrystalline materials. Nonetheless, it has been possible to increase the quality and purity of germanium polycrystals by the development of various processes, in order to obtain high quality polycrystalline materials with a maintained purity. This highly purified polycrystalline material is now being used in a variety of industrial and technological purposes, where its electrical and optical properties are necessary for the development of optoelectronic and microelectronic devices.
