One Material. Every Critical Industry.
High-purity fused silica is one of the most versatile engineering materials in modern industry. From the diffusion furnace tube that dopes a silicon wafer to the crucible that grows the crystal, from the UV cuvette in a spectrophotometer to the heater envelope in a car-body curing oven — quartz glass enables processes that no other affordable material can. FGQuartz has manufactured these components since 2005.
Semiconductor
Diffusion tubes · wafer boats · CVD
Optical
Optical quartz glassUV windows · lenses · laser optics
Laboratory
Crucibles · cuvettes · ICP torches
Fiber Optic
MCVD tubes · VAD rods · OVD
Solar & PV
CZ crucibles · DS casting · cell lines
High-Temp
IR heaters · furnace tubes · probes
Est. 2005
Lianyungang, Jiangsu
40+ Countries
Global export network
6 Major Industries
Full application coverage
Full Custom
From prototype to production
Quartz Glass Across Every Critical Sector
Each industry that depends on quartz glass places a distinct set of demands on the material — different purity levels, different geometries, different thermal and chemical environments. FGQuartz has dedicated engineering knowledge for each of the six major application industries it serves.
Silicon Wafer Processing
From the diffusion tube that forms the p-n junction to the wafer boat that carries silicon through a 900°C furnace, quartz glass defines the purity envelope of front-end semiconductor manufacturing. Metallic contamination from process components directly degrades transistor performance — making quartz glass purity a device yield variable, not merely a quality preference.
- Diffusion & process tubes (LPCVD, CVD, oxidation)
- Wafer boats & carriers — 100 mm to 300 mm
- Gas injectors & injector rings
- Quartz flanges, liners & endcaps
- Wet process tanks for HF / SC1 / SC2
- Custom CNC-machined quartzware
Laser Systems & UV Optics
Fused silica transmits from 150 nm in the deep ultraviolet through to 3.5 µm in the near-infrared — a spectral breadth no other optical glass matches. Combined with near-zero birefringence, high laser damage threshold, and low fluorescence background, it is the default optical material for UV lithography, excimer laser systems, spectroscopy instruments, telescope mirror substrates, and scientific optical instruments of all kinds.
- UV & optical windows (JGS1 / JGS2 grade)
- Plano-convex, plano-concave & cylindrical lenses
- Prisms — right-angle, equilateral, Dove, Porro
- Mirror blanks & etalon substrates
- UV cuvettes & spectroscopy flow cells
- UV lamp envelopes & excimer lamp tubes
Research & Analytical Chemistry
Laboratory quartz glass is chosen wherever standard borosilicate fails — above 500°C, below 300 nm, or where the ultra-low boron and alkali blank of fused silica is required for trace element analysis. From the crucible ignited in a 1000°C muffle furnace to the ICP torch sustaining a 6000 K argon plasma, quartz glass is the material enabling the clean analytical results that laboratories depend on.
- Quartz crucibles — low-form & tall-form with lids
- Combustion & evaporation boats
- Beakers, flasks & round-bottom flasks
- ICP plasma torch assemblies — all major platforms
- Sub-boiling acid distillation stills
- Tube furnace liners & reaction tubes
Preform Manufacturing & Draw
Every optical fiber begins as a fused silica preform, and the substrate tubes, reaction vessels, and deposition mandrels used to build that preform must be made from the same high-purity glass as the fiber itself. Hydroxyl content, geometric uniformity, and metallic purity of the substrate tube translate directly into the fiber’s transmission loss, polarisation mode dispersion, and cut-off wavelength. FGQuartz serves MCVD, VAD, and OVD preform producers across all fiber types.
- MCVD substrate tubes — matched to lathe OD
- VAD reaction tubes & low-OH starting rods
- OVD mandrels & deposition chamber parts
- Overclad & jacketing tubes
- Fluorine-doped depressed-cladding tubes
- PCF capillary tubes & PM fiber jacket tubes
Silicon Growth & Cell Fabrication
From the quartz crucible holding 400 kg of molten silicon in a Czochralski puller to the diffusion tube doping solar cell emitters at 900°C, quartz glass is the defining consumable of the entire photovoltaic manufacturing chain. Transition metal contamination from quartz components creates recombination centres that directly reduce solar cell efficiency — making purity grade selection a manufacturing yield decision for every GW-scale solar cell line.
- CZ crucibles 12″ to 32″ — single-pull & CF-CZ
- DS crucibles G5 / G6 / G7 / G8
- Phosphorus diffusion tubes (POCl₃ / PH₃)
- Wafer boats M10 (182 mm) & G12 (210 mm)
- PECVD bell jars & LPCVD process tubes
- Siemens CVD bell jars & electrode sleeves
Heating, Furnaces & Thermal Processing
When industrial processes demand temperatures above 500°C — beyond the range of borosilicate glass and most engineering polymers — quartz takes over. Operating continuously at 1200°C and briefly to 1300°C, with near-zero thermal expansion that survives rapid cycling, and chemical resistance to most industrial process gases, fused silica is the practical choice across industrial heating, furnace, chemical processing, and plasma applications worldwide.
- Infrared heater tubes & envelopes (SW / MW)
- Industrial process tubes & furnace liners
- Thermocouple protection tubes (single & double bore)
- High-temperature sight glasses & observation windows
- Combustion chamber liners & muffle inserts
- Electrical insulators & HV feed-throughs
The Six Properties That Make Quartz Glass Irreplaceable
No single alternative material simultaneously provides all six of these properties. The combination is what places fused silica at the centre of modern high-technology manufacturing.
Continuous service to 1200°C and short-term excursions to 1300°C — beyond borosilicate, most ceramics, and engineering metals. The softening point of fused silica is above the melting point of aluminium.
A coefficient of thermal expansion orders of magnitude lower than other glass types or metals means fused silica resists thermal shock, maintaining dimensional stability through the rapid heating and cooling cycles of industrial and laboratory processes.
Transmission from 150 nm in the deep ultraviolet through 3.5 µm in the near-infrared — enabling UV photochemistry, infrared heating, pyrometric temperature measurement, and optical spectroscopy across the same material.
Resistant to nearly all mineral acids, oxidants, halogens, and process gases at elevated temperatures. Does not leach boron, alkali metals, or transition metals into the process environment — critical for trace element analysis and contamination-sensitive manufacturing.
High-purity fused silica achieves SiO₂ content above 99.99%, with transition metal impurities at sub-ppm levels. Semiconductor wafer processing, solar silicon growth, and analytical chemistry all depend on quartz components that do not contaminate the silicon crystal or analytical sample with metallic impurities.
Fused silica maintains its electrical insulation characteristics at temperatures where most polymer insulators would melt or become conductive. This property is essential for plasma reactor electrode holders, high-voltage vacuum feed-throughs, and furnace heating element supports.
Founded in 2005 in Lianyungang, Jiangsu Province, FGQuartz has spent two decades manufacturing exclusively from fused silica and high-purity quartz glass — building the accumulated process knowledge that allows the engineering team to advise on material selection, not just supply a catalogue part.
Semiconductor, optical, laboratory, fiber optic, solar photovoltaic, and high-temperature industrial — FGQuartz’s production facility and engineering team cover all six major application categories of high-purity quartz glass under one roof at Lianyungang.
FGQuartz ships to customers in more than eighty countries across North America, Europe, Asia-Pacific, the Middle East, and beyond. Direct export from Lianyungang port reaches most global destinations by sea freight; express airfreight covers urgent orders with three to five business day transit times to major industrial markets.
No minimum order is imposed on custom components. Research groups evaluating a new process design, OEM engineers qualifying a component for a new instrument, and production buyers trialling a new supplier can all order prototype quantities of a single piece without surcharges or extended lead times.
Which Quartz Products Serve Which Industries
Many quartz glass products are used across multiple industries. This reference shows the primary and secondary application of FGQuartz’s core product families across the six industries served.
| Product Family | Semiconductor | Optical | Laboratory | Fiber Optic | Solar PV | High-Temp |
|---|---|---|---|---|---|---|
| Quartz Tubes & Process Tubes | ● | ✓ | ● | ● | ● | ● |
| Quartz Crucibles | ✓ | — | ● | — | ● | ✓ |
| Wafer Boats & Carriers | ● | — | — | ✓ | ● | ✓ |
| Windows & Optical Elements | ✓ | ● | ✓ | ✓ | ✓ | — |
| Cuvettes & Flow Cells | — | ● | ● | — | — | ✓ |
| Lenses, Prisms & Mirrors | ✓ | ● | — | ✓ | ✓ | — |
| Preform Substrate Tubes | ✓ | — | — | ● | — | — |
| Gas Injectors & Manifolds | ● | — | — | ✓ | ✓ | ● |
| Thermocouple Protection Tubes | ✓ | — | ✓ | — | ✓ | ● |
| Wet Process Tanks | ● | — | ● | — | ● | — |
| UV Lamp Envelopes | — | ● | ✓ | — | — | ● |
| Furnace Liners (clear & opaque) | ● | — | ● | ● | ● | ● |
| ICP Torch Assemblies | — | — | ● | — | — | ✓ |
| Custom CNC Components | ● | ● | ● | ● | ● | ● |
● Core application · ✓ Secondary application · — Not typically used
Understanding Quartz Glass Across All Applications
The same fundamental material properties that make fused silica useful in semiconductor diffusion furnaces also make it useful in infrared heaters and optical spectroscopy — but different applications emphasise different aspects of those properties. Understanding these relationships helps in selecting the right grade and form for each use.
Why the Same Material Serves Such Different Industries
It may seem surprising that the same fused silica material appears in a semiconductor diffusion furnace, a UV spectrophotometer, an optical fiber preform lathe, and an automotive paint-curing oven. The connection is the unique combination of properties that fused silica offers: no other affordable material simultaneously provides extreme thermal stability, near-zero thermal expansion, UV-to-infrared transparency, chemical inertness, and electrical insulation at high temperatures. Different industries exploit different subsets of these properties — semiconductor manufacturing primarily needs purity and thermal stability; optical applications need UV transparency and low birefringence; industrial heating needs thermal stability and infrared transparency — but the underlying material is the same across all of them.
How Purity Grade Requirements Differ by Application
Not all quartz glass applications require the same level of purity, and selecting a higher grade than necessary adds cost without benefit. Optical applications requiring deep-UV transmission — excimer laser optics, UV spectroscopy, germicidal UV lamps — need synthetic high-OH (JGS1) fused silica because only this grade transmits efficiently below 250 nm. Semiconductor and solar applications require high-purity natural fused silica (JGS2 equivalent) for low metallic contamination without the OH-related near-infrared absorption that would be irrelevant in these applications. Industrial heating applications can often use commercial-grade quartz where the purity requirements are less stringent. FGQuartz stocks and manufactures across all these grades and advises customers on the appropriate selection for each application.
The Clear vs. Opaque Grade Choice Across Industries
Clear fused silica and opaque quartz are variants of the same base material — silicon dioxide — but opaque quartz is processed to contain microscopic voids that scatter infrared radiation rather than transmitting it. This gives opaque quartz very different thermal behaviour: low emissivity, thermal insulation, and opacity to infrared. In semiconductor manufacturing, clear process tubes allow pyrometric temperature sensing; opaque furnace liners provide thermal insulation. In industrial heating, clear heater envelopes transmit infrared from the element to the workpiece; opaque reflector shields direct that infrared in the desired direction. In laboratory furnaces, clear tubes allow visual inspection of the sample; opaque liners reduce heat loss from the furnace body. The choice between grades is not a quality decision — it is a functional specification decision that depends on whether you need the glass to transmit or block infrared.
Devitrification: The Shared Failure Mode Across All High-Temperature Applications
Whether a quartz component is a semiconductor diffusion tube, a solar furnace liner, a laboratory muffle insert, or an industrial infrared heater envelope, all high-temperature quartz glass components share the same primary failure mechanism: devitrification. This is the crystallisation of the amorphous fused silica surface into cristobalite, occurring above approximately 1050°C, accelerated dramatically by alkali metal contamination from the process environment or from handling without gloves. Devitrified quartz is structurally weaker, generates particles, and indicates that the component should be replaced. Managing devitrification risk through operating temperature choice, surface cleanliness practices, and timely replacement is the most important maintenance consideration that spans all high-temperature quartz applications regardless of industry.
Why China-Based Manufacturing Does Not Mean Compromised Quality
The assumption that Chinese-manufactured quartz glass components are necessarily lower quality than those from Japanese or European suppliers reflects historical market conditions that no longer apply to specialist manufacturers like FGQuartz. The raw material — high-purity quartz sand and synthetic silica precursors — is an internationally traded commodity available at the same specification globally. The manufacturing processes — arc fusion, CNC grinding, oxy-hydrogen flame forming — use equipment and techniques that are fully transferable regardless of geography. The purity verification tools — ICP-MS analysis — are standard laboratory instruments. What differentiates quality is the process knowledge, quality discipline, and testing rigour of the individual manufacturer, not the country in which they operate. FGQuartz competes on these factors, not on a price-for-quality trade-off.
When to Choose a Custom Component vs. a Standard Catalogue Part
Standard catalogue quartz components — tubes in common diameters, crucibles in standard volumes, cuvettes in standard path lengths — exist because the most common applications converge on a small set of frequently used dimensions. For these applications, catalogue items are faster, cheaper, and lower-risk than custom fabrication. Custom components are appropriate when: the required dimensions fall outside the standard range; the component has geometric features (ports, flanges, specific end configurations, complex curvature) that cannot be achieved with standard tube and rod stock; or when the application is a novel design where no standard exists yet. FGQuartz produces both standard and custom items from the same facility, with no surcharge on custom orders beyond the additional fabrication time required.