Quartz Glass vs Ordinary Glass: Understanding the Differences for Precision Applications
Glass is a staple in modern industry, but when it comes to high-performance applications like semiconductor manufacturing, optical systems, UV sterilization, and high-temperature labs, quartz glass stands out. This article will explore the key differences between quartz glass and ordinary glass, focusing on their microstructure, thermal properties, chemical resistance, and optical performance, helping you choose the best material for your needs.
1. What Is Quartz Glass vs Ordinary Glass?
Quartz Glass (Fused Silica):
Quartz glass, or fused silica, is a non-crystalline material made primarily of silicon dioxide (SiO₂). It's manufactured by melting high-purity quartz or synthetic silica at temperatures of around 2000°C. The result is a glass with exceptional purity (≥99.99% SiO₂), free from metal oxides and contaminants.
Ordinary Glass (Soda-Lime and Borosilicate):
Ordinary glass, such as soda-lime glass, is made by melting a mixture of silica sand, sodium carbonate, and lime at around 1400°C. Borosilicate glass, which offers better thermal resistance, is made by adding boron trioxide to silica, but still contains metal oxides.
2. Microstructure: Why Purity Matters
Quartz glass has a highly uniform atomic structure, formed entirely of interconnected SiO₂ tetrahedra. This gives it exceptional strength, resistance to chemicals, and low defect levels.
Ordinary glass, on the other hand, contains metal oxides that introduce structural irregularities. These impurities cause higher thermal expansion and reduced chemical durability. In sensitive environments like semiconductor fabs, this can lead to contamination.
Key takeaway: Quartz glass's pure microstructure makes it essential for ultra-clean and high-precision industrial applications.
3. Thermal Properties: High Resistance to Heat
Melting & Softening Points:
| Material | Melting Point (°C) | Softening Point (°C) |
|---|---|---|
| Quartz Glass | ~1700 | ~1700 |
| Borosilicate | ~820 | ~820-860 |
| Soda-Lime Glass | ~1400 | ~720-750 |
Quartz glass can withstand much higher temperatures than ordinary glass, making it ideal for applications involving extreme heat, such as furnaces and reactors operating above 1200°C.
Thermal Expansion:
| Material | Thermal Expansion Coefficient (× 10⁻⁶ /°C) |
|---|---|
| Quartz Glass | ~0.5 |
| Borosilicate | ~3.3 |
| Soda-Lime Glass | ~9 |
Quartz glass's ultra-low thermal expansion ensures stability during rapid heating or cooling, preventing cracking or warping — crucial for applications like semiconductor diffusion furnaces and laser optics.
4. Chemical Resistance: Durability in Harsh Environments
Quartz glass excels in chemical resistance, withstanding strong acids and bases like hydrochloric acid (HCl) and hydrofluoric acid (HF) without degrading. It doesn't release metal ions, making it ideal for sensitive processes in semiconductor manufacturing and clean environments.
Ordinary glass types, especially soda-lime, corrode easily under similar conditions. This compromises their durability and the purity of the processes they're involved in.
Key takeaway: Quartz glass is the material of choice for high-purity applications like acid cleaning tanks and chemical etching chambers.
5. Optical Properties: Clarity and UV Transmission
Quartz glass offers excellent transparency, transmitting over 90% of UV light, along with visible and infrared light. In contrast, ordinary glasses absorb UV light and degrade over time.
| Property | Quartz Glass | Borosilicate Glass | Soda-Lime Glass |
|---|---|---|---|
| UV Transmission | >90% (down to 170nm) | ~50% (below 300nm) | Very low |
| Visible Clarity | High | Moderate | Moderate |
| IR Transmission | Excellent | Fair | Poor |
Quartz glass's high UV transparency is critical for applications like photolithography, UV curing lamps, and sterilization systems.
6. Common Industrial Applications
Quartz Glass:
- Semiconductor processing: Furnace tubes, wafer boats, etching tanks
- Optical devices: Lenses, prisms, UV windows
- UV lamps and sterilizers
- High-temperature labware and crucibles
- Aerospace and scientific instrumentation
Ordinary Glass:
- Household glassware, windows, bottles
- Moderate-temperature laboratory equipment
- Light bulbs, general optical uses without UV requirements
7. Cost Considerations: Is Quartz Glass Worth the Investment?
Quartz glass can be 3-5 times more expensive than borosilicate or soda-lime glass. However, its long-term durability, thermal performance, and chemical purity make it a cost-effective choice for critical applications.
Using quartz glass can reduce:
- Equipment downtime due to failure
- Contamination risks and defects
- Frequent maintenance and replacements
For high-tech industries, including semiconductors, solar cell manufacturing, and optics, quartz glass delivers unmatched ROI despite the higher upfront cost.
8. Frequently Asked Questions (FAQ)
Q1: Can quartz glass be used in place of ordinary glass in ovens?
- Quartz glass is ideal for ovens that operate above 1200°C. For lower-temperature ovens, borosilicate glass is often sufficient and more cost-effective.
Q2: Why doesn't quartz glass yellow over time?
- Quartz glass does not contain metal oxide additives, which are responsible for UV-induced discoloration. It maintains its clarity even under intense UV exposure.
Q3: Can quartz glass crack from thermal shock?
- Quartz glass has excellent thermal shock resistance, but sudden extreme cooling can still cause damage.
Q4: Is quartz glass environmentally safe?
- Yes. Quartz glass is chemically inert and does not leach harmful substances during use or disposal.
9. Conclusion: Choosing Between Quartz Glass and Ordinary Glass
For applications that require high heat resistance, chemical purity, and optical clarity, quartz glass is the superior material. Ordinary glass is suitable for general use, but falls short in high-precision, high-temperature environments.
At FG Quartz, we specialize in custom quartz glass solutions tailored to your industry needs — from semiconductor wafer carriers to UV sterilization tubes and high-temperature labware. Our products meet strict quality standards, ensuring smooth and efficient processes.
Contact FG Quartz for Expert Quartz Glass Solutions:
📧 Email: fgquartz@outlook.com
🌐 Website: www.fgquartz.com
