Etching Fused Silica

Etching Fused Silica: Fused Silica, CTE 0.55 x 10^-6 /K; depth control +/-1 um. No MOQ, prototypes in 5-10 days, DFM review with every RFQ.

Technical Guide July 17, 2026 Updated July 17, 2026

Quick answer: Etching Fused Silica covers Fused Silica (CTE 0.55 x 10^-6 /K, 185 nm – 2.5 um); Etching to depth control +/-1 um. Prototypes ship in 5-10 working days.

etching fused silica is a materials problem before it is a machining problem. Fused Silica has near-zero thermal expansion and a Knoop hardness of 500 kg/mm2, so the etching recipe – feeds, coolant, tooling – differs from what works on ordinary float glass. The line runs buffered HF wet benches and masked lithography line and holds depth control +/-1 um.

Key parameters

Material Fused Silica (JGS1 (UV), JGS2 (standard), JGS3 (IR))
Thermal expansion (CTE) 0.55 x 10^-6 /K
Service temperature 1,100 C continuous
Transmission range 185 nm – 2.5 um
Density 2.20 g/cm3
Knoop hardness 500 kg/mm2
Refractive index 1.458 @ 587 nm
Stock thickness 0.10 – 50 mm
Maximum blank size 450 x 450 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

Design guidance

The shop-floor rules that matter here:

  • Material note: its hardness and brittleness demand diamond tooling and controlled feeds.
  • 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.

Capabilities and limits

The core strength of Etching is microchannels, cavities and frosted textures without mechanical stress. The honest limit: isotropic undercut roughly equals depth, so masks are compensated at layout time. Both belong on the drawing before quoting, not after.

One material, many routes: on Fused Silica we also quote drilling, edge grinding, grinding, lapping, and multi-step drawings are the norm rather than the exception.

Where these parts end up

Orders for etching fused silica cluster in scientific instruments (reference flats, cells, prism mounts, stage inserts); mems devices (cap wafers, TGV substrates, motion-sensor lids); ccd inspection equipment (CCD cover plates, reference grids, stage glass). Background reading on the underlying material science: RP Photonics: fused silica.

Dimensions still moving? Configure this part live in the 3D builder below, or open the full custom glass machining 3D builder to start from a blank canvas.

Useful companion pages: CNC machining capability, material selection guide, optical glass options.

Buyer questions, answered

What tolerances are achievable on Fused Silica parts?

Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Its hardness and brittleness demand diamond tooling and controlled feeds.

What thickness range do you stock for Fused Silica?

Standard stock spans 0.10 – 50 mm, with blanks up to 450 x 450 mm. Other formats are sourced per order.

How does Fused Silica behave under heat?

CTE is 0.55 x 10^-6 /K and continuous service reaches 1,100 C continuous, which is what drives its use where near-zero thermal expansion 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.

Specifications on this page were last reviewed by our engineering team in July 2026.

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