Uncoated Glass Products
Uncoated Glass Products
NEXTERION® Future in your hands

BOROFLOAT® 33 (NEXTERION® Glass B)
BOROFLOAT® 33 is a borosilicate glass produced with a microfloat process by melting the purest raw materials. It is one of the basic materials for the NEXTERION® coated and uncoated substrates.
The manufacturing process used for this glass type results in a pristine, fire-polished surface that can be used without any additional polishing. BOROFLOAT® 33 is a highly chemically resistant material with excellent transmission, low fluorescence, exceptional flatness and tight geometric properties.
Manufactured using standardized processes and running a stringent quality control system, BOROFLOAT® 33 is the perfect material to be used for coated substrates. The uncoated type of this glass is available exclusively cleanroom cleaned (ISO class 5) and will be offered in standard and custom formats.
- Chemical and Thermal Stability
BOROFLOAT® 33 glass exhibits excellent chemical stability and durability. The glass provides an inert support for biomolecule immobilization and hybridization, and does not leach alkali ions over time.
A particularly low coefficient of thermal expansion is what makes BOROFLOAT® glass remarkably resistant to high temperature levels. The glass is proven to stand up to high and fluctuating temperatures.
- Fluorescence
The extremely low fluorescence of the glass offers exceptionally low background signals for all fluorescence detection methods, thereby maximizing the signal-to-background ratios.
- Flatness
Exceptional flatness, tight thickness tolerances.
- Roughness
≤1 nm RMS (typical)
- Cleaning
All NEXTERION® substrates are cleaned using an automated ultrasonic cleaning line using multiple wash steps of varying pH levels, rinse steps and a final drying stage.
- Packaging
After cleaning, the substrates will be either coated or, in the case of uncleaned substrates, packed up in plastic storage boxes which are sealed in air-tight laminated foil pouches under inert atmosphere in an ISO class 5 (Class 100) clean room. The glass can be used without any additional cleaning step.

D263® Family
The D263® family are borosilicate glasses produced with a down draw process by melting the purest raw materials. Different technical properties may be offered. D263® is the basic material for NEXTERION® coated and uncoated coverslips.
The manufacturing process used for this glass types results in two pristine, fire-polished surface that can be used without any additional polishing. All D263® glasses are highly chemically resistant materials with excellent transmission, low fluorescence, exceptional flatness and tight geometric properties.
D263® is manufactured using standardized processes and running a stringent quality control system. The uncoated type of this glass is available exclusively cleanroom cleaned (ISO class 5) and will be offered in standard and custom formats.
- Chemical and Thermal Stability
D263® glass exhibits excellent chemical stability and durability. The glass provides an inert support for biomolecule immobilization and hybridization, and does not leach alkali ions over time.
A low coefficient of thermal expansion makes D263® glass remarkably resistant to high temperature levels. The glass is proven to stand up to high and fluctuating temperatures.
- Fluorescence
The low fluorescence of the glass offers exceptionally low background signals for all fluorescence detection methods, thereby maximizing the signal-to-background ratios.
- Flatness
Exceptional flatness, tight thickness variation.
- Roughness
≤1 nm RMS
- Cleaning
All NEXTERION® substrates are cleaned using an automated ultrasonic cleaning line using multiple wash steps of varying pH levels, rinse steps and final drying stage.
- Packaging
After cleaning, the substrates will be either coated or, in the case of uncleaned substrates, packed up in plastic storage boxes which are sealed in air-tight laminated foil pouches under inert atmosphere in an ISO class 5 (Class 100) clean room. The glass may be used without any additional cleaning steps.
Customized Material
The manufacture of special technical glass is one of the SCHOTT group’s core competencies. SCHOTT produces an extremely wide range of technical glass types, including borosilicate and optical glass. The standard materials NEXTERION® uses are Borofloat®33 and the D263® family. Both materials can be used for most of the applications in life science and diagnostic industry.
If your special application requires a very special substrate material (e.g. fused silica), we would be pleased to discuss your requirements. The SCHOTT group produces several hundred different types of glass, which means that the range of glass thicknesses available is very wide, ranging from 30 µm up to 254 mm depending on the glass type.