YT-220 Large-Format Synthetic Quartz Tube — High-Purity Fused Silica Furnace Tube (OD φ200–350 mm)
LUMIGLAS® YT-220 is a high-purity large-format synthetic quartz tube produced from 6N-grade fused silica (SiO₂ ≥99.9999%) with all metallic impurities controlled below 0.005 ppm (wt). Designed for semiconductor diffusion furnace outer tubes, oxidation furnace jacket tubes and large-OD sleeve assemblies. Standard OD range φ200–350 mm, wall thickness 6–15 mm, maximum length 1500 mm. Custom dimensions available.
Description
The LUMIGLAS® YT-220 large synthetic quartz tube is a high-purity fused silica furnace tube engineered for semiconductor diffusion furnace outer tubes, oxidation furnace jacket sleeves and large-OD quartz sleeve assemblies. Produced from synthetic fused silica with SiO₂ purity ≥99.9999% (6N grade), the YT-220 controls all ten major metallic impurity elements to below 0.005 ppm (wt) — meeting the ppb-level contamination requirements of production-scale silicon wafer thermal processing.
Unlike natural fused quartz tubes, which carry inherent metallic impurities from the source sand, the YT-220 uses CVD-derived synthetic silica to achieve true 6N purity with ultra-low OH hydroxyl content. In addition, the tube wall is produced to a bubble-free standard — no bubbles are visible to the naked eye — eliminating the stress concentrators that cause premature cracking in large-OD furnace tubes during thermal cycling. Consequently, the YT-220 delivers the purity, dimensional stability and thermal durability required for high-volume semiconductor furnace applications.
Technical Specifications — YT-220 Large Synthetic Quartz Tube
| Parameter | Value / Grade |
|---|---|
| Product Type | High-purity large-format synthetic quartz tube / large diameter fused silica tube |
| Material | Synthetic fused silica — SiO₂ ≥99.9999% (6N grade) |
| OH Content | Ultra-low hydroxyl (low-OH) grade |
| Metallic Impurities | All major elements (Li, Na, K, Mg, Ca, Cu, Al, Cr, Fe, Ti) <0.005 ppm (wt) |
| Max. Service Temperature | ~1200°C continuous service |
| Thermal Expansion | 0.55 × 10⁻⁶ /°C — near-zero thermal expansion |
| OD Range | φ200 – 350 mm |
| Wall Thickness (WT) | 6 – 15 mm (standard); up to 35 mm available |
| Max. Length | ≤1500 mm |
| Bubble Standard | No bubbles visible to the naked eye |
| Material Certificate | Full impurity analysis Certificate of Conformity (CoC), supplied as standard |
Major Metallic Impurity Content — YT-220
All values in ppm (wt). Full impurity analysis Certificate of Conformity (CoC) provided as standard with every order.
| Grade | Li | Na | K | Mg | Ca | Cu | Al | Cr | Fe | Ti |
|---|---|---|---|---|---|---|---|---|---|---|
| YT-220 | <0.001 | <0.005 | <0.002 | <0.001 | <0.003 | <0.001 | <0.003 | <0.001 | <0.001 | <0.001 |
Geometric Specifications & Dimensional Tolerances
OD = outer diameter · WT = wall thickness. Custom dimensions and tighter tolerances available on request — specify OD × WT × Length (mm) when enquiring.
| Grade | OD (mm) | WT (mm) | OD Tol. (mm) | WT Tol. (mm) | Out-of-Round. (mm) | Eccentricity (mm) | CSA Rel. Diff. | Bow (mm/m) | Length (mm) |
|---|---|---|---|---|---|---|---|---|---|
| Large-Format Sleeve Tube |
200–350 | 6–35 | ±1.50 | ±1.00 | ≤0.40 | ≤0.45 | ≤6.0% | ≤0.70 | ≤1500 |
* Custom OD, WT and length outside the standard range available on request. Provide drawing or OD × WT × Length specification when enquiring.
Why Specify YT-220 for Large-OD Diffusion Furnace Applications?
In large-OD semiconductor furnace tubes, two failure mechanisms drive replacement cycles — metallic contamination migration and thermally-induced cracking. Conventional natural fused quartz tubes carry ppb-to-ppm level Na, Al and Fe impurities that migrate into the wafer stack at 900–1100°C process temperatures. Furthermore, bubble inclusions in the tube wall act as stress concentrators, accelerating crack initiation during the rapid thermal ramp cycles typical of production furnaces. The YT-220 addresses both mechanisms: 6N synthetic silica eliminates metallic contamination, while the bubble-free wall standard removes the structural weak points that cause premature tube failure.
6N Purity — SiO₂ ≥99.9999%
Synthetic CVD-grade fused silica eliminates the metallic impurities present in natural quartz sand. All major elements are controlled to <0.005 ppm (wt) — meeting ppb-level requirements for advanced semiconductor furnace applications.
Bubble-Free Wall Standard
No bubbles visible to the naked eye — the YT-220 wall is free of inclusion defects that act as stress concentrators during thermal cycling, delivering longer service life in production furnace environments.
Large OD up to φ350 mm
The YT-220 covers the φ200–350 mm OD range required for horizontal and vertical diffusion furnace outer tubes and jacket sleeves — sizes not available in standard small-format quartz tube product lines.
Ultra-Low OH Content
Ultra-low hydroxyl (low-OH) grade minimises OH-related infrared absorption and reduces hydroxyl diffusion into the process environment — critical for dry oxidation and high-temperature annealing processes.
Typical Applications
- ▸Diffusion furnace outer tubes and jacket sleeves — large-OD outer shell for horizontal and vertical silicon wafer diffusion furnaces, OD φ200–350 mm
- ▸Thermal oxidation furnace outer tubes — protective and structural outer sleeve in dry and wet oxidation furnaces for silicon wafer processing
- ▸LPCVD and CVD furnace jacket tubes — large-diameter outer containment sleeve in low-pressure chemical vapour deposition furnace configurations
- ▸High-temperature annealing and RTP accessories — large-OD quartz sleeve components in rapid thermal processing and annealing furnace systems
- ▸Semiconductor OEM quartz components — custom large-format quartz tube fabrication for semiconductor equipment manufacturers requiring non-standard OD, WT or length specifications
Technical Document & Download
📄 Technical Datasheet — YT-220
Full impurity data, product characteristics, geometric tolerance table and ordering specification.
Frequently Asked Questions
Request a Quote — LUMIGLAS® YT-220 Large Synthetic Quartz Tube
Specify: OD × WT × Length (mm) · Quantity · CoC required · Custom dimensions welcome





