Product Knowledge · 2024-01-10 · 7 min read
Introduction to Quartz Glass
Fused quartz glass (also called fused silica) is manufactured by melting high-purity silicon dioxide (SiO₂) at extremely high temperatures. With a purity of >99.9% SiO₂, it offers performance characteristics far beyond conventional borosilicate glass.
Key Advantages
Extreme Temperature Resistance
Quartz glass can withstand continuous operating temperatures up to 1100°C, with short-term exposure to 1300°C. This makes it indispensable in applications where borosilicate glass would fail.
Ultra-Low Thermal Expansion
With a coefficient of thermal expansion of only 0.55 × 10⁻⁶/K (compared to 3.3 for borosilicate), quartz glass is virtually immune to thermal shock. It can be heated to 1000°C and plunged into cold water without cracking.
UV Transparency
Unlike borosilicate glass, fused quartz transmits UV light with >85% transmission at 200nm wavelength. This makes it essential for:
- UV sterilization systems
- UV curing processes
- Spectroscopy and analytical instruments
- Semiconductor photolithography
Chemical Purity
The extremely high purity of fused quartz (>99.9% SiO₂) makes it ideal for semiconductor manufacturing, where even trace contamination can ruin entire production batches.
Applications
Semiconductor Manufacturing
Quartz tubes are used as process tubes in diffusion furnaces, oxidation furnaces, and LPCVD systems for semiconductor wafer processing.
Chemical Processing
High-temperature reactors, distillation columns, and heat exchangers in the chemical industry use quartz tubes where corrosive media at high temperatures are present.
Laboratory Equipment
Quartz tubes are standard equipment in analytical laboratories for combustion analysis, thermal analysis, and high-temperature experiments.
Quartz vs. Borosilicate Comparison
| Property | Quartz | Borosilicate 3.3 |
|---|---|---|
| Max Temperature | 1100°C | 500°C |
| CTE (×10⁻⁶/K) | 0.55 | 3.3 |
| UV Transmission | Excellent | Poor |
| Purity | >99.9% SiO₂ | ~80% SiO₂ |
| Cost | High | Moderate |
Conclusion
Quartz glass tubes represent the pinnacle of glass technology for demanding industrial and scientific applications. While more expensive than borosilicate glass, their superior performance in extreme conditions makes them the only viable choice for many critical applications.