12 Inch (300 mm) Alkali-Free Glass Wafers: Alkali-Free Glass (CTE 3.2 x 10^-6 /K, 350 nm – 2.0 um); 300 mm format, TTV <5 um. Single-piece prototypes to production volumes, quoted from your drawing.
A wafer is a specification bundle, not just a disc. 12 inch (300 mm) alkali-free glass wafers here mean AF32 / EAGLE-class display glass material with certified CTE of 3.2 x 10^-6 /K, TTV controlled per format, and edges profiled for handler compatibility.
The numbers
| Material | Alkali-Free Glass (AF32 / EAGLE-class display glass) |
|---|---|
| Thermal expansion (CTE) | 3.2 x 10^-6 /K |
| Service temperature | 600 C (Tg 717 C) |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.43 g/cm3 |
| Knoop hardness | 590 kg/mm2 |
| Refractive index | 1.51 @ 587 nm |
| Stock thickness | 0.10 – 1.1 mm |
| Maximum blank size | 400 x 300 mm |
| Diameter / format | 300 mm |
| Thickness | 0.7 – 1.1 mm |
| TTV | <5 um |
| Flat / notch | SEMI notch |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
DFM notes from the shop floor
Three items decide most of the cost and lead time on this work:
- Material note: thin sheets below 0.3 mm demand carrier-supported handling through every step.
- Specify flat or notch orientation relative to your device layout – regrinding orientation later scraps the wafer.
- Over-specification is the quiet budget killer: a 20/10 scratch-dig face costs roughly three times an 80/50 face, so grade each surface individually.
The full rules live in our tolerance design guide and holes and edges design guide.
Manufacturing capability
One material, many routes: on Alkali-Free Glass we also quote laser cutting, grinding, edge grinding, dicing, and multi-step drawings are the norm rather than the exception.
Typical applications
12 inch (300 mm) alkali-free glass wafers shows up across oled packaging (cover lids, frit-seal frames, fill-port plates); mems devices (cap wafers, TGV substrates, motion-sensor lids). Background reading on the underlying material science: SCHOTT AF 32 eco.
The fastest route to a quote is geometry: use the 3D builder below, draw a dimensioned 2D drawing from it, or open the site-wide custom glass machining 3D + 2D builder for fully custom parts.
Related reading on this site: alkali-free display glass, alkali-free glass wafers, custom FTO glass.
Buyer questions, answered
Do parts ship with inspection data?
Dimensional reports, surface certificates and material certs per melt are available; specify the level on the RFQ.
What tolerances are achievable on Alkali-Free Glass parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Thin sheets below 0.3 mm demand carrier-supported handling through every step.
What thickness range do you stock for Alkali-Free Glass?
Standard stock spans 0.10 – 1.1 mm, with blanks up to 400 x 300 mm. Other formats are sourced per order.
How does Alkali-Free Glass behave under heat?
CTE is 3.2 x 10^-6 /K and continuous service reaches 600 C (Tg 717 C), which is what drives its use where no alkali ion migration into TFT or sensor layers matters.
Is there a minimum order for 12 inch (300 mm) alkali-free glass wafers?
No. Single prototypes are accepted, and pricing steps down at 10, 100 and 1,000 pieces.
Specifications on this page were last reviewed by our engineering team in October 2026.