Monocrystalline and polycrystalline introduction and differences

Although from the current situation, to make solar power have a large market, accepted by the majority of consumer, it must improve the photoelectric conversion efficiency of solar cells, reduce production costs. From the current development of the international solar cell can be seen that its development trend was monocrystalline silicon, polycrystalline silicon, ribbon silicon, thin film materials (including microcrystalline silicon thin film, compound base film and dye film).

The daily seen solids can be divided into two major categories of non-crystal and crystal, the internal atomic arrangement of non-crystalline material without a certain rule, when fracturing, the fracture is random, such as plastic and glass, but the substance called crystal, its appearance represent natural regular polyhedron, with a clear edge and flat, the atoms are in accordance with certain rules arranged together neatly, so that when broken off it also according to a certain plane, such as salt, crystal and so on .

According to metal powder supplier, some crystals are composed of many small grains, if the arrangement between grains without rules, this crystal called polycrystalline crystal, such as copper and iron. But there are also have a crystal that it itself is a complete large grain, this crystal called single crystal, such as crystal and diamond.

Monocrystalline cells have good cell conversion efficiency, good stability, but the cost is higher. Polycrystalline silicon with low cost, conversion efficiency slightly lower than monocrystalline silicon solar cells, a variety of defects in materials, such as grain boundaries, dislocations, micro defects and impurities of carbon and oxygen in the material, as well as the contamination transition metal in the process. Monocrystalline silicon can be used for diode, rectifier level, circuit level and the production and deep process manufacturing of solar cell grade monocrystalline products, its subsequent product integrated circuits and semiconductor separation devices have been widely used in various fields, in the military electronic equipment also occupies an important position.

In the photovoltaic technology and micro semiconductor inverter technology rapid development today, solar cells produced by using monocrystalline silicon can be directly turned solar energy into light energy, achieve a move towards green energy revolution. Now, the international solar photovoltaic power plant has reached a theory mature stage, is translating to the practical application stage, the utilization of solar monocrystalline silicon will be spread to all over the world, the market demand is self-evident.

Monocrystalline silicon products including round rods, sheets and square rods, sheets, suitable for a variety of semiconductor, electronics production, its products quality inspected through the current world's most advanced testing equipment, reached the world advanced level. Uses: It is a raw material for manufacturing semiconductor silicon devices, used for producing power rectifiers, power transistors, diodes, switching devices.

Polysilicon is the direct feedstock to produce monocrystalline silicon, is the electronic information base material of contemporary artificial intelligence, automatic control, information processing, photoelectric conversion and other semiconductor devices, referred to as "the cornerstone of microelectronics building". Polysilicon is a form of elemental silicon. Obtain by dry silicon powder and dry hydrogen chloride gas chloridized under certain conditions, then by condensation, distillation, reduction. When molten elemental silicon solidified in cold conditions, the silicon atoms are in a form of diamond crystal arranged to a plurality of nuclei, if these nuclei grow into crystal orientation different grains, then these grains combined with each other, and crystallize into polysilicon. Polysilicon can be used for the material of preparing single crystal silicon, the differences between polycrystalline and monocrystalline was mainly in the physical properties.

Source:http://www.mhcmp.com