Quick answer: 8 Inch (200 mm) Alkali-Free Glass Wafers covers Alkali-Free Glass (CTE 3.2 x 10^-6 /K, 350 nm – 2.0 um); 200 mm format, TTV <4 um. Prototypes ship in 5-10 working days.
A wafer is a specification bundle, not just a disc. 8 inch (200 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 | 200 mm |
| Thickness | 0.7 – 1.1 mm |
| TTV | <4 um |
| Flat / notch | SEMI notch |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Design guidance
Before sending the RFQ, check these against your drawing:
- 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.
What the process holds
Beyond this page, Alkali-Free Glass routinely runs through edge grinding, cnc machining, dicing, grinding in our shop – most real parts combine two or three of these steps.
Who orders this
Orders for 8 inch (200 mm) alkali-free glass wafers cluster in ccd inspection equipment (CCD cover plates, reference grids, stage glass); industrial displays (touch covers, gauge windows, printed bezels); 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.
Engineers scoping this work usually also review alkali-free display glass, alkali-free glass wafers, holes and edges design guide.
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.
Specifications on this page were last reviewed by our engineering team in October 2026.