Double-Side Polishing Borofloat 33 Wafers: Borofloat 33 (CTE 3.25 x 10^-6 /K, 350 nm – 2.0 um); Double-Side Polishing to TTV under 3 um. Single-piece prototypes to production volumes, quoted from your drawing.
Ask any process engineer what makes borofloat 33 difficult and the answer is specific: float tin side must be tracked when parts see coating or bonding steps. Our double-side polishing line is tooled around exactly that – planetary double-side polishers with carrier plates – holding TTV under 3 um on parts from 0.1 – 10 mm thick.
Specification envelope
| Material | Borofloat 33 (SCHOTT float production, wafer grade) |
|---|---|
| Thermal expansion (CTE) | 3.25 x 10^-6 /K |
| Service temperature | 450 C continuous |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.23 g/cm3 |
| Knoop hardness | 480 kg/mm2 |
| Refractive index | 1.471 @ 587 nm |
| Stock thickness | 0.70 – 25.4 mm |
| Maximum blank size | 500 x 500 mm |
| Process | Double-Side Polishing |
| Working tolerance | TTV under 3 um |
| Minimum feature | Ra below 0.5 nm both faces |
| Surface finish | 60/40 to 20/10 both faces |
| Thickness window | 0.1 – 10 mm |
| Edge condition | edge-rounded before DSP |
| Wafer formats | 2", 3", 4", 6", 8" and 12" with SEMI flats or notch |
| TTV | under 3 – 5 um by format |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Manufacturing capability
The core strength of Double-Side Polishing is wafer-grade parallelism and sub-nanometer roughness on both faces simultaneously. The honest limit: parts must be round or near-round; strongly asymmetric outlines wedge in the carriers. Both belong on the drawing before quoting, not after.
One material, many routes: on Borofloat 33 we also quote edge grinding, laser cutting, etching, sandblasting, and multi-step drawings are the norm rather than the exception.
DFM notes from the shop floor
Before sending the RFQ, check these against your drawing:
- Material note: float tin side must be tracked when parts see coating or bonding steps.
- Process boundary: parts must be round or near-round; strongly asymmetric outlines wedge in the carriers.
- 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.
Typical applications
Orders for double-side polishing borofloat 33 wafers cluster in microfluidic devices (chips, manifolds, via plates, bonded stacks); led packaging (groove covers, phosphor carriers, package windows); machine vision (camera windows, ring-light diffusers, calibration plates). Background reading on the underlying material science: SCHOTT BOROFLOAT product page.
Dimensions still moving? Configure this part live in the 3D + 2D builder below, or open the full custom glass machining 3D + 2D builder to start from a blank canvas.
Useful companion pages: 4 inch Borofloat wafers, wafer dicing process, custom microfluidic chip.
Buyer questions, answered
What equipment runs the double-side polishing work?
Planetary double-side polishers with carrier plates.
Is there a minimum order for double-side polishing borofloat 33 wafers?
No. Single prototypes are accepted, and pricing steps down at 10, 100 and 1,000 pieces.
How fast can prototypes ship?
Machined prototypes ship in 5 – 10 working days. Coated or bonded parts add 1 – 2 weeks depending on queue slots.
What files do you need for a quote?
A dimensioned PDF plus DXF or STEP geometry. If only a sketch exists, our drawing review service formalizes it before quoting.
Do parts ship with inspection data?
Dimensional reports, surface certificates and material certs per melt are available; specify the level on the RFQ.
Specifications on this page were last reviewed by our engineering team in September 2026.