High UV transmission round clear fused quartz disc

The core material of fused quartz disc is amorphous silica, which does not have the piezoelectric effect. However, its excellent optical properties (high light transmittance, wide light transmission band), extremely low coefficient of thermal expansion, high chemical stability and heat resistance make it widely used in optics, semiconductors, optical communications and other fields.

 The core of the manufacturing process of clear fused quartz disc is to melt quartz sand raw materials at high temperatures to form a homogeneous glass body, followed by hot forming and cold working.

Phase One: Raw material preparation and melting

This is the foundation of the entire process, determining the purity and basic properties of the material.

1. Quartz glass plate Raw material selection and processing

• Raw materials: High-purity natural quartz sand or synthetic silicon powder is used. For optical-grade applications, extremely high purity is required, and the total metal impurity content usually needs to be less than a few parts per million (ppm).
• Processing: The raw materials need to be purified through physical and chemical methods such as flotation, magnetic separation, and acid washing to remove impurities such as metal ions and dust.

2. Melting

• Objective: To convert crystalline quartz sand (SiO₂) into amorphous fused quartz glass.
• Methods: There are mainly two types
• Electric melting method:

In an electric furnace protected by vacuum or inert gas (such as argon), a temperature exceeding 2000°C is provided by an arc generated by electrodes or a graphite heater.

This method can produce fused quartz with extremely low hydroxyl (OH⁻) content, which is suitable for applications in the ultraviolet band

• Flame fusion Method:

Quartz sand powder is sprayed onto the target through a hydrogen-oxygen flame or an oxygen-hydrogen flame, and then deposited layer by layer by cladding.

The fused quartz produced by this method usually contains a relatively high OH content, is suitable for the infrared band, and can be used to manufacture large-sized blanks.

3. Forming and annealing

• Objective: To shape molten quartz glass into the required initial form (such as block, rod, plate) and eliminate internal stress.
• Process: The molten quartz glass liquid is injected into the mold or a "blank" of a specific shape is formed by controlling the cooling process. Subsequently, the blank is sent into the annealing furnace and slowly passes through a precisely controlled temperature range (for example, from above 1100°C to below 800°C). This process can minimize and homogenize internal thermal stress to the greatest extent, preventing cracking or deformation during subsequent processing or use.

Advantages of quartz disc:

• Exceptional Optical Properties:

• High Transmission:Quartz disc Offers very high transmission across a broad spectral range, from deep ultraviolet (UV) to near infrared (NIR).
• Low fluorescence: Quartz disc has inherently low background fluorescence, which is critical for sensitive optical measurements.

• Outstanding Thermal Stability:

• Extremely Low Thermal Expansion Coefficient: Highly resistant to thermal shock and deformation under rapid temperature changes.
• High Softening Point: Quartz disc can withstand very high operating temperatures. Quartz plate can resist 1100 degree for long time and the short time working temperature is 1200 degree.

• Excellent Chemical Purity and Resistance:

• Inertness: Highly resistant to corrosion by most acids, salts, and metals. In addition to hydrofluoric acid, quartz glass almost does not react with other acids for chemical treatment, and its acid resistance is 30 times that of its acid resistance ceramic and stainless steel 150 times.

• Excellent electrical insulation performance:

The resistance value of quartz disc is equivalent to 10,000 times that of ordinary glass. It is an excellent electrical insulating material and maintains good electrical properties even at high temperatures ‌

• High Purity: Quartz disc can be produced with extremely low levels of impurities, preventing contamination in sensitive processes.
• Superior Electrical Insulation: Quartz disc possesses high dielectric strength and low dielectric loss.
• High Laser Damage Threshold: Quartz disc can withstand high-power laser beams without being damaged, making it ideal for laser applications.

Main Application Fields:

• Optics and Photonics:

• Lenses, Windows, and Prisms: Used in UV lithography equipment, high-power laser systems, telescopes, and spectroscopic instruments.
• Optical Fibers: The core material for high-purity optical fibers used in telecommunications and data transmission.

• Semiconductor Manufacturing:

• Wafer Carriers & Process Tubes: Used as crucibles, diffusion tubes, and wafer boats in high-temperature processes for growing silicon crystals and fabricating chips due to its purity and thermal stability.

• Lighting:

• High-Intensity Discharge (HID) Lamps: Used as the envelope material for mercury, metal halide, and xenon arc lamps because it can withstand high temperatures and UV radiation.

• Laboratory Equipment:

• Cuvettes & Labware: Used for UV-Vis spectroscopy and in applications requiring chemical inertness and thermal shock resistance.

Technical Data of Clear Quartz disc