Quick answer: Etching Borosilicate Glass covers Borosilicate Glass (CTE 3.3 x 10^-6 /K, 360 nm – 2.0 um); Etching to depth control +/-1 um. Prototypes ship in 5-10 working days.
The combination of Borosilicate Glass and Etching comes up constantly in RFQs for a reason – the material offers thermal shock resistance, and Etching is the right way to get accurate geometry into it. Expect depth control +/-1 um and isotropic smooth walls.
The numbers
| Material | Borosilicate Glass (3.3 expansion group per ISO 3585) |
|---|---|
| Thermal expansion (CTE) | 3.3 x 10^-6 /K |
| Service temperature | 450 C continuous |
| Transmission range | 360 nm – 2.0 um |
| Density | 2.23 g/cm3 |
| Knoop hardness | 480 kg/mm2 |
| Refractive index | 1.473 @ 587 nm |
| Stock thickness | 0.50 – 30 mm |
| Maximum blank size | 600 x 400 mm |
| Process | Etching |
| Working tolerance | depth control +/-1 um |
| Minimum feature | 10 um channel width (masked HF) |
| Surface finish | isotropic smooth walls |
| Thickness window | 0.1 – 5 mm |
| Edge condition | stress-relief etch available |
| 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: sheet stock carries more thickness variation than float wafer stock, so lapping is often the first step.
- Process boundary: isotropic undercut roughly equals depth, so masks are compensated at layout time.
- 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
Etching earns its place through microchannels, cavities and frosted textures without mechanical stress. Its boundary condition – isotropic undercut roughly equals depth, so masks are compensated at layout time – is the first thing our DFM review checks.
Beyond this page, Borosilicate Glass routinely runs through ultrasonic machining, double-side polishing, polishing, grinding in our shop – most real parts combine two or three of these steps.
Application context
etching borosilicate glass shows up across medical diagnostics (flow cells, slides, microplate bottoms, cuvette windows); scientific instruments (reference flats, cells, prism mounts, stage inserts); laboratory instruments (cuvettes, sight glasses, stir-cell windows). Background reading on the underlying material science: ISO 3585 borosilicate glass 3.3.
The fastest route to a quote is geometry: use the 3D configurator below, or the site-wide custom glass machining 3D builder for fully custom parts.
Engineers scoping this work usually also review glass sandblasting, material selection guide, high-temperature quartz windows.
Frequently asked questions
What tolerances are achievable on Borosilicate Glass parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Sheet stock carries more thickness variation than float wafer stock, so lapping is often the first step.
What thickness range do you stock for Borosilicate Glass?
Standard stock spans 0.50 – 30 mm, with blanks up to 600 x 400 mm. Other formats are sourced per order.
How does Borosilicate Glass behave under heat?
CTE is 3.3 x 10^-6 /K and continuous service reaches 450 C continuous, which is what drives its use where chemical durability matters.
What accuracy does etching hold?
Depth control +/-1 um with minimum features of 10 um channel width (masked HF). Isotropic undercut roughly equals depth, so masks are compensated at layout time.
What equipment runs the etching work?
Buffered HF wet benches and masked lithography line.
Specifications on this page were last reviewed by our engineering team in July 2026.