Materials
Quartz glass melted with various kinds of pure natural quartz
Construction Feature Of Quartz Glass
Pure quartz glass is composed of a single silica (SiO₂) component, and the Si-O bonds in quartz glass are arranged in a short-range ordered and long-range disordered state.Due to the strong and stable bond energy of the Si-O bond, quartz glass has a high softening temperature, excellent spectral transmittance,Very low coefficient of thermal expansion and conductivity, very high chemical stability, radiation resistance and long working life features under extreme conditions.
Optical property
Quartz glass has a range of excellent optical properties. Compared with ordinary glass, high-purity quartz glass has good transmittance in an extremely wide spectrum from the far ultraviolet (160nm) to the far infrared (5μm), which is not available in general optical glass. The excellent spectral transmittance and optical uniformity make quartz glass widely used in semiconductor lithography and precision optical devices.In addition, quartz glass has good radiation resistance, the quartz glass with radiation resistant has been widely used as a window material for spacecraft, protective covers for key components of the space laboratory.
Mechanical property
Quartz glass is similar with ordinary glass, they are brittle and hard material. same as like the ordinary glass, the strength parameters of quartz glass are affected by many factors.Including surface state, geometry and test method. The compressive strength of transparent quartz glass is generally 490~1960MPa,The tensile strength is 50~70MPa, the bending strength is 66~108MPa, and the torsional strength is about 30MPa.
Electrical properties
Quartz glass is an excellent electrical insulating material. Compared with ordinary glass, quartz glass has a higher resistivity, and the resistivity of quartz glass at room temperature is as high as 1.8×1019Ω∙cm. In addition, quartz glass has a higher breakdown voltage (about 20 times that of ordinary glass) and a lower dielectric loss.The resistivity of quartz glass decreased slightly with the increase of temperature, and the resistivity of opaque quartz glass was lower than that of transparent quartz glass.
Thermal property
Because the quartz glass is almost all the strong Si-O bond, its softening temperature is very high, and the long-term working temperature can reach 1000℃.In addition, the thermal expansion coefficient of quartz glass is the lowest among common industrial glass, and its linear expansion coefficient can reach 5×10-7/℃. Specially treated quartz glass can even achieve zero expansion. Quartz glass also has very good thermal shock resistance,Even if it repeatedly experiences a large temperature difference in a short period of time, it will not crack. These excellent thermal properties make quartz glass irreplaceable in high temperature and extreme working environments.
High purity quartz glass can be used in chip manufacturing in the semiconductor industry,Auxiliary materials for optical fiber manufacturing, observation Windows for industrial high-temperature furnaces, high-power electric light sources, and the surface of the space shuttle as a thermal insulation layer.The extremely low coefficient of thermal expansion also allows quartz glass to be used in precision instruments and lens materials for large astronomical telescopes.
Chemical properties
Quartz glass has very good chemical stability. Unlike other commercial glass, quartz glass is chemically stable to water, Therefore, it can be used in water distillers that require very high purity of water. Quartz glass has excellent acid and salt resistance, Therefore, it can be used in water distillers that require very high purity of water. Quartz glass has excellent acid and salt resistance, Except hydrofluoric acid, phosphoric acid and basic salt solutions, it does not react with most acids and salt solutions. Compared to acid and salt solutions, Quartz glass has poor alkaline resistance and reacts with alkali solutions at high temperatures. In addition, quartz glass and most oxides,Metals, nonmetals, and gases do not react at normal temperatures. The extremely high purity and good chemical stability make quartz glass suitable for use in environments with high production conditions in semiconductor manufacturing.
Other properties
Permeability: The structure of quartz glass is very relaxed, and even at high temperatures it allows ions of certain gases to diffuse through the network.The diffusion of sodium ions is the fastest. This performance of quartz glass is particularly important for users, for example, when quartz glass is used as a high-temperature container or diffusion tube in the semiconductor industry, due to the high purity of the semiconductor material, the refractory material in contact with quartz glass as a furnace lining must be pre-processed by high temperature and cleaning, removing alkaline impurities of potassium and sodium, and then can be put into quartz glass for use.
Application Of Quartz Glass
As an important material, quartz glass is widely used in optical communication, aerospace, electric light source, semiconductor, optical new technology.
1. Optical communication field: quartz glass is an auxiliary material for the production of optical fiber prefabricated rods and optical fiber drawing, mainly serving the base station interconnection market, and the arrival of the 5G era has brought huge market demand for optical fiber.
2. New light aspect: high pressure mercury lamp, xenon lamp, tungsten iodide lamp, thallium iodide lamp, infrared lamp and germicidal lamp.
3. Semiconductor aspect: Quartz glass is an indispensable material in the production process of semiconductor materials and devices, such as the Grown germanium, Crucible of silicon single crystal, furnace core tube and bell jar...etc.
4. In the field of new technology: with its excellent performance of sound, light and electricity, ultrasonic delay line on radar, infrared tracking direction finding, Prism, lens of infrared photography, communication, spectrograph, spectrophotometer, reflecting window of large astronomical telescope, high temperature operation window, Reactors, radioactive installations; Rockets, Nose cone of missiles , nozzles and radome, Radio insulation parts for artificial satellites; thermobalance, vacuum adsorption device, precision casting...etc.
Quartz glass is also used in chemical industry, metallurgy, electrical, scientific research and other aspects. In the chemical industry, can do high temperature acid resistant gas combustion,Cooling and ventilation devices; Storage device; Preparation of distilled water, hydrochloric acid, nitric acid, sulfuric acid, etc., and other physical and chemical experiments.In high temperature operation, it can be used as electric furnace core tube and gas combustion radiator. In optics, quartz glass and quartz glass wool can be used as rocket nozzles,Spacecraft heat shield and observation window, in a word, with the development of modern science and technology, quartz glass has been more widely used in various fields.
Application Areas Of Quartz Glass
With excellent physical and chemical properties, quartz glass is widely used in high temperature, clean, corrosion resistance, light transmission, filtering and other specific high-tech product production process environment, is an indispensable important material in semiconductor, aerospace, optical communication fields.
Semiconductor field
Semiconductor quartz glass products account for 68% of the quartz glass products market, and the semiconductor field is the largest application field in the quartz glass downstream market. Quartz glass materials and products are widely used in semiconductor chip manufacturing process, and are required to carry devices and cavity consumables for semiconductor etching, diffusion, oxidation processes.
Optical communication field
Quartz rods are the main raw material for optical fiber manufacturing. More than 95% of the prefabricated fiber bars are divided into high-purity quartz glass, and a lot of quartz glass materials are consumed in the production process of fiber bar making and wire drawing, such as holding rods and quartz cups.
Optics filed
Synthetic quartz glass material is used as lens, prism, TFT-LCD HD display and IC light mask substrate material in the high-end optical field.
Quartz glass products are key consumables and raw materials in various fields, restricting the production of products in the downstream industry, and there is no alternative product at present, so the demand for quartz glass is long-term. In the downstream industries, especially the accelerated development of semiconductor and photovoltaic industries, the prosperity of the quartz glass industry will continue to increase.
| Flame fused Quartz | Electric Fused Quartz | Opaque Quartz | Synthetic Quartz | ||
| Mechanical Properties | Density（g/cm3） | 2.2 | 2.2 | 1.95-2.15 | 2.2 |
| Young's Modulus（Gpa） | 74 | 74 | 74 | 74 | |
| Poisson's Ratio | 0.17 | 0.17 | 0.17 | ||
| Bending St reng th（MPa） | 65-95 | 65-95 | 42-68 | 65-95 | |
| Compressive St reng th（MPa） | 1100 | 1100 | 1100 | ||
| Tensile St reng th（MPa） | 50 | 50 | 50 | ||
| Torsional St reng th（MPa） | 30 | 30 | 30 | ||
| Mohs Hardness（MPa） | 6-7 | 6-7 | 6-7 | ||
| Bubble Diameter（pm） | <100 | ||||
| Electrical Properties | Dielectric Constant（10GHz） | 3.74 | 3.74 | 3.74 | 3.74 |
| Loss Factor（10GHz） | 0.0002 | 0.0002 | 0.0002 | 0.0002 | |
| Dielec trie St reng th（V/m） | 3.7X107 | 3.7X107 | 3.7X107 | 3.7X107 | |
| Resistivity（20°C）（Q・cm） | >1X1016 | >1X1016 | >1X1016 | >1X1016 | |
| Resistivity（1000℃）（Q •cm） | >1X106 | >1X106 | >1X106 | >1X106 | |
| Thermal Properties | Softening point（C） | 1670 | 1710 | 1670 | 1600 |
| Annealing point（C） | 1150 | 1215 | 1150 | 1100 | |
| St rain Point（C） | 1070 | 1150 | 1070 | 1000 | |
| Thermal Conductivity（W/M・K） | 1.38 | 1.38 | 1.24 | 1.38 | |
| Specific Heat（20℃）（J/KG・K） | 749 | 749 | 749 | 790 | |
| Expansion Coefficient（X10-7/K） | a：25C~200C 6.4 | a：25C~100C 5.7 | a：25C~200C 6.4 | a：25C~200C 6.4 | |