High pure graphite generally refers to the amount of carbon in the 99.99% above the stone ink, in the organization structure can be divided into three kinds of coarse grain structure, fine particle structure and ultrafine particles structure, high pure graphite is used in a large number of single crystal silicon furnace. The base material for integrated circuit is mainly silicon single crystal chip, the silicon single crystal growth process is mainly uses the Czochralski (CZ), and other methods of magnetic Czochralski method (MCZ), regional (Fz) method and double crucible pulling method, Czochralski silicon accounted for about 80% of the total amount of silicon single crystal for the global electronics industry, Czochralski silicon furnace graphite piece is a consumable by high pure graphite material processing into Czochralski silicon furnace heating system. In 2005 China needs to use graphite about 800 t in the single crystal furnace.
Another important purpose of high pure graphite is processed into various kinds of crucible, used in the production of precious metals, rare metals or high purity metals, non-metallic materials. The graphite electrode is also a kind of high purity graphite, which can be used for the analysis of the spectra of all the elements except carbon. Impurities of finished product should be not more than 6 * 10 in spectrum analysis in preparation of standard sample and catch impurities set required spectral pure carbon powder or spectral pure graphite toner by chemical method and. These two kinds of high purity materials of impurity content requirements are in 6 * 10; in some uses, the need to contain carbon content up to 99.9995%, total ash content of less than 5 * 10. There are three kinds of molding methods of high purity graphite, such as extrusion molding, molding, and so on.
