JGS1 Quartz Glass for UV Optical and Precision Components

Why Material Choice Decides UV Component Performance

In deep ultraviolet optical systems, the glass substrate is often the limiting factor. Standard optical glasses absorb strongly below 300 nm, reducing throughput and causing thermal lensing. JGS1 quartz glass — a synthetic fused silica with high hydroxyl (OH) content — solves this by offering transmission of ≥90% at 185 nm and exceptional purity, making it the reference material for excimer lasers, semiconductor wafer inspection, and UV spectroscopy. Coating selection then fine-tunes surface reflection, environmental durability, or electrical conductivity, but it can only optimize what the base material delivers. Choosing the right combination from the start avoids costly redesigns.

Available Glass Materials as Labeled Options

Understanding the landscape of optical materials helps procurement teams evaluate whether JGS1 is the right fit or if an alternative meets a different cost-performance point. Common categories include:

• Fused Silica (Synthetic): JGS1 (far UV grade, ~2000 ppm OH), JGS2 (UV/visible grade, lower OH), JGS3 (IR grade, very low OH). Equivalents: Corning 7980, Suprasil 1. JGS1 is optimized for the shortest UV wavelengths.
• Fused Quartz (Natural): Lower purity than synthetic silica; used where UV requirements are less stringent.
• Borosilicate Glass: (e.g., BK7, Borofloat) — cost-effective for visible and near-UV, but cuts off sharply below 300 nm.
• Soda-Lime Glass: Economical for visible-only applications; unsuitable for UV or high-temperature precision.
• Aluminosilicate Glass: Chemically strengthened for scratch-resistant cover windows; limited UV transmission.
• Sapphire: Transmits from 150 nm to 5 µm, extremely hard and chemically inert, but high cost and birefringence can affect polarization-sensitive optics.
• Optical Glass (Specialty): Schott N-BK7, UV-grade fused silica from other manufacturers — each with trade-offs in refractive index homogeneity and spectral range.

Key Properties and Trade-Offs

When comparing these materials for a UV precision component, the following attributes matter:

• Deep UV Transmission: JGS1 delivers ≥90% at 185 nm. JGS2 drops to about 50% at 185 nm but is sufficient above 220 nm. Borosilicate and soda-lime absorb almost completely below 300 nm. Sapphire transmits well to 150 nm but introduces birefringence.
• Thermal Stability: JGS1’s CTE is ~0.55×10⁻⁶/°C, virtually unchanged over wide temperature ranges, enabling near-zero thermal distortion in laser cavities. Borosilicate has higher CTE (~3.3×10⁻⁶), risking figure errors under temperature swings.
• Chemical Resistance: Synthetic fused silica resists most acids except hydrofluoric; it is sensitive to alkaline contaminants, so cleaning protocols matter. Sapphire is superior in harsh chemical environments.
• Hardness & Mechanical Strength: JGS1 is hard (Mohs ~6.5) but brittle. Sapphire is harder (Mohs 9) and more scratch-resistant, often chosen for windows exposed to particle impact.
• Cost Factor: JGS1 is more expensive than JGS2 or borosilicate due to its synthetic process and higher purity. Sapphire is the most costly. For large volumes where deep UV is not required, JGS2 or an aluminosilicate may lower total system cost.

Coating and Surface-Treatment Options

Coatings tailor JGS1’s surface properties without undermining its bulk advantages. Common options for UV components:

• Anti-Reflection (AR) Coatings: Broadband or narrowband (e.g., 193 nm, 248 nm) single- or multi-layer dielectric coatings reduce reflectance from ~4% per surface to <0.5%. High laser-damage threshold designs are critical for excimer applications.
• Mirror Coatings: Dielectric high-reflectors (e.g., >99% at 266 nm) or protected aluminum coatings for UV reflectors. Note: metallic mirrors can absorb some UV energy, raising thermal concerns.
• ITO (Indium Tin Oxide) Coatings: Transparent conductive layers for applications needing EMI shielding or heated windows; they add slight absorption and must be deposited at low temperatures to avoid damaging the substrate.
• Hydrophobic / Oleophobic Coatings: Easy-clean surfaces for medical or field-portable instruments; these can wear over time and may slightly alter transmission.
• Chemical Strengthening: Possible for aluminosilicate but not typically applied to JGS1; however, edge treatments like etching can improve fracture resistance.
• Thermal Tempering: Not standard for fused silica due to its high intrinsic thermal shock resistance, but available for large borosilicate windows.

Trade-offs revolve around wavelength specificity, durability, and additional cost. A narrowband AR coating achieves the highest performance but limits flexibility; a broadband design trades peak transmission for wider usefulness.

Selecting the Right Material and Coating for Your Application

Mapping the combination to the use case ensures performance without over-engineering:

• Deep UV Lasers & Lithography (193 nm, 248 nm): JGS1 with high-damage-threshold AR coatings is standard. JGS2’s lower transmission at these wavelengths leads to unacceptable losses.
• UV Disinfection & Curing (254 nm, 365 nm): JGS2 often suffices with a simple AR coating, reducing cost. For high-fluence curing, JGS1’s thermal stability is beneficial.
• Semiconductor Inspection: JGS1 with ITO coating may combine UV transmission with static dissipation.
• Outdoor UV Sensors: Hydrophobic coating plus UV-grade silica like JGS1 prevents water spotting that would degrade signal.

Regulatory compliance: JGS1 quartz glass is inherently RoHS-compliant (no lead, cadmium, etc.) and typically meets REACH requirements as a non-hazardous article. Suppliers can provide declarations upon request. For medical or food-contact applications, additional extraction testing may be needed, but the base material poses no toxicological risk.

Need a Material Recommendation?

The optimal choice hinges on wavelength, power level, environment, and budget. Our team can analyze your requirements and propose a specific JGS1 grade (or alternative) paired with a suitable coating. Reach out with your target specifications for a technical consultation.

Why JGS1 Quartz Glass Excels in UV Precision Components

JGS1 quartz glass distinguishes itself through exceptional deep-UV transmission — exceeding 90% at 185 nm — combined with thermal resilience and optical homogeneity. Its synthetic origin yields a consistently high hydroxyl content (~2000 ppm), which suppresses absorption bands in the ultraviolet, making it the preferred substrate for UV lithography optics, excimer laser windows, and fluorescence analysis components. When a design demands prolonged UV exposure without solarisation-induced transmission loss, JGS1 delivers stable performance that natural quartz cannot match.

Key Facts About JGS1 Quartz Glass

• Far-ultraviolet transparent: usable from 185 nm through the near-infrared.
• Softening point above 1600°C; continuous service temperature of 1100°C.
• Extremely low thermal expansion (CTE ~5.5×10⁻⁷/°C), akin to Corning 7980.
• Synthetic fused silica with total impurity levels typically below 50 ppm.
• Resistant to most acids, water, and organic solvents.

Specification and Manufacturing Capabilities

Procuring precision JGS1 quartz glass components requires balancing optical, mechanical, and dimensional specifications. The sections below outline the attributes suppliers often quote and the tolerance ranges achievable with proper lapping, polishing, and coating processes.

Dimensional Tolerances and Form Factors

JGS1 can be supplied as round or square 2× 100 mm JGS1 & JGS2 Quartz Glass Sheets, thinner wafers, discs, or complex shapes. Thickness can range from 0.2 mm to over 30 mm. Diameters or edge lengths up to 300 mm are common for cover-glass and window applications. Tight dimensional control — down to ±0.05 mm — is achievable through CNC machining and double-sided lapping. For microfluidic or semiconductor use, custom hole patterns and edge chamfers are also available.

Surface Quality and Polish Options

Surface finish directly impacts UV scatter and transmission. Polished JGS1 typically reaches a surface roughness below 1 nm RMS and flatness better than λ/4 per 25 mm aperture. Scratch-dig specifications of 60-40 or better are standard for UV optics. Double-sided polishing ensures parallelism within 10 arcseconds for interferometric applications. An as-received (flame-polished) finish may suffice for non-imaging components, but lapped and polished surfaces are recommended when stray light must be minimised. For semiconductor applications, Fused Silica Glass Wafers (2–12″, JGS1/JGS2) are available with custom edge profiles and surface finishes.

Typical Lead Times and Order Requirements

Prototype quantities often ship within 2–3 weeks, while larger production batches may require 4–8 weeks depending on complexity and coating cycles. Minimum order quantities depend on the part geometry; small runs for R&D are generally accepted. Volume pricing applies after agreed-upon initial samples. Every order includes material certification, dimensional inspection reports, and, when requested, spectral transmission curves.

Coating and Post-Processing Notes

As discussed earlier, anti-reflection, ITO, and hydrophobic coatings enhance JGS1’s utility in UV systems. These are applied in-house or through qualified partners. AR coatings centred at 248 nm or 193 nm can push transmission above 99% on a single surface. Cleanroom packaging (Class 1000 or better) prevents particle contamination before integration.

Consolidated Overview of JGS1 Quartz Glass Options

Submit Your Specifications for a Quotation

Whether you need a single prototype or a production run, our team can fabricate JGS1 quartz glass parts to your exact specifications. Provide your drawings, desired coatings, and performance criteria for a prompt technical and commercial response.