AF 32® eco

The alkali-free AF 32® eco is both environmentally friendly and technically impressive, with high transmission levels and excellent dielectric properties. With tight geometric tolerances and a CTE similar to that of a silicon wafer, this unique glass has a wide array of advantages for a large number of industries.

The eco-friendly answer to high technical demands

Alkali-free with a low CTE

One of the eco-friendly characteristics of AF 32® eco is its alkali-free composition, making it highly suitable for semiconductor systems. With a similar CTE to a silicon wafer, it can be used as a high-quality wafer-thin glass cover or substrate for silicon chips in semiconductors and MEMS devices.

Wide thickness range, tight geometrical tolerance

AF 32® eco is available in a wide variety of thicknesses, from an extremely thin 30 µm up to 0.5 mm. Whatever thickness you require, the total thickness variation (TTV) factor remains tightly controlled, at just ≤ 5 µm to 15 µm.

Outstanding transmission levels

Light transmission achieved by AF 32® eco glass is consistently strong both in the visible range and at higher wavelengths up to near-infrared. It achieves an exceptional luminous transmittance level of 91.9 %, but after AR coating, transmission can reach 97-99 %.

Excellent dielectric properties

The low dielectric loss of AF 32® eco allows applications at very high frequencies. The thermal expansion (CTE) is matched to silicon and allows co-processing with silicon wafers. This allows for example to realize SAW and BAW filter in the GHz range with low insertion loss.

Material properties

Optical properties

Chart showing the optical properties of SCHOTT AF 32® eco


Thermal properties

Chart showing the thermal properties of SCHOTT AF 32® eco


Mechanical properties

Chart showing the mechanical properties of SCHOTT AF 32® eco


Transmittance values

Chart showing the transmittance values of SCHOTT AF 32® eco


Spectral transmittance (250 - 3150 nm)

Chart showing the spectral transmittance (250 - 3150 nm) of SCHOTT AF 32® eco


Spectral transmittance (250 - 450 nm)

Chart showing the spectral transmittance (250 - 500 nm) of SCHOTT AF 32® eco


Electrical properties

Chart showing the electrical properties of SCHOTT AF 32® eco


Chemical properties

Chart showing the chemical properties of SCHOTT AF 32® eco

AF 32® eco products

SCHOTT AF 32® eco is available as:

  • Sheets
  • Cut-to-size substrates
  • Unpolished substrates and wafers

To find out more, please see the related products on the overview page.

Want to know more? Let’s talk

Whether you need more information, samples, a quote, or advice for a project, we would be delighted to talk to you.

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