Fused Silica Glass

Very low coefficient of thermal expansion (approximately 0.5 × 10⁻⁶ /°C)

Material	Fused Silica Glass
Density	2.20 g/cm³
Roughness	Ra0.002μm
Maximum size	ф500*50mm

Introduction

Fused Silica Glass is widely used in high-tech fields such as semiconductors, optics, and scientific research due to its excellent physical and chemical properties. It is composed of amorphous materials of high-purity silicon dioxide SiO₂ (>99.9%), which does not contain other oxides and avoids impurities. At the same time, Fused Silica has strong resistance to acids, alkalis and most corrosive substances, and is suitable for extreme chemical environments. The following is a detailed introduction to its characteristics and applications.

Fused Silica Glass Advantages

✅ High purity >99.9% SiO₂

✅ Extremely low thermal expansion coefficient (0.5 × 10⁻⁶ /°C) and strong thermal shock resistance

✅ High resistivity

✅ Strong resistance to chemicals

✅ High transmittance from deep ultraviolet to infrared (175 nm ~ 2500 nm), suitable for optical applications

✅ High mechanical strength, precision polishable surface

Application

✅ Photolithography masks, photolithography machine lenses, wafer carriers, heat treatment boats, cavity windows

✅ Ultraviolet lenses, laser windows, reflector substrates

✅ Infrared/ultraviolet windows, high-speed aircraft windows

✅ Quartz cuvettes, laser cavity lenses

✅ Optical path components for spectrometers and chromatographs

✅ High-temperature gas sensor windows

✅ Microstructure devices, optical trap structures, vacuum cavity windows

✅ Interferometers, gyroscope substrates

Fused Silica Glass Properties

Material Properties

Property	Unit	Fused Silica Glass
Density	g/cm³	2.2
Bending Strength	MPa	80
Compressive Strength	MPa	1100
Elastic Modulus	GPa	220
Poisson’s Ratio	–	0.17
Young’s Modulus	GPa	72

Thermal Properties

Property	Unit	Fused Silica Glass
Thermal Conductivity	W/m·K	1.38
Melting Point	°C	1730
Maximum Operating Temperature	°C	1200
Linear Expansion Coefficient	10⁻⁶/K	0.55

Electrical Properties

Property	Unit	Fused Silica Glass
Dielectric Constant	1 MHz	3.75
Breakdown Voltage	V/cm	400
Dielectric Loss	1 MHz	< 0.0004
Resistivity	Ω·cm	> 10¹⁸

Fused Silica Glass Machining

Fused Silica Glass Manufacturer

High-Purity Fused Silica Glass Manufacturer & Precision Machining Expert
We are a professional manufacturer of high-purity fused silica glass, offering integrated services from material supply to precision CNC machining. With advanced 3-axis, 4-axis, and 5-axis machining capabilities, we produce custom components with ultra-tight tolerances (±0.001 mm), optical-grade polishing (up to 1/20λ), and complex geometries.

Our fused silica parts are widely used in semiconductors, optics, aerospace, analytical instruments, and scientific research. Backed by ISO 9001 and ISO 14001 certifications, we ensure stable quality, fast delivery, and technical support tailored to your critical applications.

FAQ

Is fused silica the same as quartz glass?

No.
Fused silica refers to amorphous SiO₂. Quartz is crystalline.
They behave differently under heat and stress.

What Is JGS1 Fused Silica?

JGS1 Fused Silica is a UV-grade optical quartz material characterized by high purity, excellent UV transmittance (185–2500 nm), and superior thermal stability. It is one of the three grades defined by China’s GB/T 31447.1 standard for optical fused silica (JGS1, JGS2, JGS3).

JGS1: UV-grade, best for deep-UV and precision optics.
JGS2: Standard optical grade for visible–IR.
JGS3: IR-grade, ideal for thermal or infrared applications.

Click to view our full guide to JGS1 Fused Silica

Applications of Fused Silica Glass in Semiconductor Devices

Lithography & Direct Writing, Exposure windows, mask holders
Photoresist Coating & Developing、Quartz coating covers
Wet Process Equipment, Wafer carriers and boats
Dry Etching Equipment, Quartz chamber liners, Electrode covers
Thin Film Deposition (CVD, PECVD, ALD), Chamber liners
For more semiconductor applications, please check this article (In 3 Minutes: The Complete Applications of Fused QuartzGlass in Semiconductor Equipment)

Our Fused Quartz Parts Machining Service

High-Precision Capabilities:
Complex shapes: tolerances up to ±0.01 mm
Cylindrical/shaft components: tolerances up to ±0.001 mm
Surface flatness: up to 0.001 mm
Optical flatness: up to 1/20λ (depending on wavelength)
Micro-holes: diameters as small as 0.1 mm (tolerance ±0.01 mm)
Surface roughness: Ra 0.01 μm for structural parts, Ra 0.002 μm for optical components
Surface Treatment: Polishing, optical coating

Our Fused Quartz Parts Machining Service

High-Precision Capabilities:
Complex shapes: tolerances up to ±0.01 mm
Cylindrical/shaft components: tolerances up to ±0.001 mm
Surface flatness: up to 0.001 mm
Optical flatness: up to 1/20λ (depending on wavelength)
Micro-holes: diameters as small as 0.1 mm (tolerance ±0.01 mm)
Surface roughness: Ra 0.01 μm for structural parts, Ra 0.002 μm for optical components
Surface Treatment: Polishing, optical coating

Is fused silica difficult to machine?

Yes.
It requires diamond tooling, controlled feeds, and experience.
Poor machining causes micro-cracks that reduce lifetime.