What is sapphire crystal and its application

                                                 What is sapphire crystal and its application

Sapphire crystal is aluminum oxide crystal, which is used to produce sapphire substrate

The application of sapphire crystal is the application of sapphire. As long as we know its performance, we can know where it is applied.

Sapphire crystal is hexagonal lattice structure, and many characteristics are determined by its crystal orientation. Through epitaxial crystal film growth, different crystal orientations will present different lattice and match the target material.

--Sapphire crystal has certain birefringence characteristics, and special crystal axis is used in some optical fields, such as polarized substrate:

--C-section sapphire substrate is used to grow III-V and II-VI group deposition films, such as gallium nitride, which can produce blue LED products, laser diodes and infrared detector applications.

--Type A substrates produce uniform permittivity/dielectric and are highly insulated for use in hybrid microelectronics. High temperature superconductors can be produced by A-type substrate long crystals.

--The epitaxial long crystals of silicon materials with different deposition grown on R-type substrate are used in microelectronic integrated circuits. Sapphire, due to its high capacitance, is a good choice for zui with mixed substrates, such as in microwave integrated circuits. In addition, high-speed integrated circuits and pressure sensors can be formed in the process of epitaxial silicon growth. R-type substrate growth can also be used in the fabrication of mound, other superconducting components, high resistance resistors, and gallium arsenide.

--Type M, A, R can grow non-polar or semi polar gallium nitride. As a commercial product, sapphire still needs a lot of research to improve the quality of GaN epitaxial materials. Purity:

--Sapphire crystal is a kind of insulating material, and its semiconductor characteristics are changed by doping substances and impurities. Therefore, most of the purity control is not due to the strict control of the substrate materials (silicon material, gallium arsenide, indium phosphide...), but to the change of its optical properties (color, photoconductive range) by some trace dopants, which is important for applications in some fields (optical, military).

--Because the purity of sapphire crystal has a strong impact on the electrical properties and cross contamination of metal surfaces when applied to CMOS (complementary metal oxide semiconductor), it is also important in the application of SoS (silicon on sapphire large-scale integrated circuit). It has not been proved that the purity of sapphire has an impact on the application of LED, and SoS manufacturers attribute its characteristics to the sapphire substrate. Guide mold method (edge fixing film feeding method): heating/melting → → → → placing seed crystal/pulling crystal → → → → cutting

--2 meters long, 100 mm wide ribbon or 9 * 26, 12 * 20 feet Large sapphire plate -- tubular sapphire more than 65 feet long, or other shapes

--Sapphire crystals are stretched into different crystal orientations through different substrates (A, R, C, others) and are mainly used in industrial and machinery manufacturing -- the growth rate in inert gas (nitrogen, argon) is 1-5 cm/h

--Different crystals can start to grow at the same time (sometimes more than 20 kinds)

---Pictures are for reference only