Tekglas ApS


Technical data and properties of fused silica and fused quartz

  1. Bubbles resp. inclusions with a diameter Ø <= 0,06 mm are not taken into consideration when singularly present.
  2. Shadow method and interferometer were used to striations.
  3. Valid for thermally reshaped material.
  4. Interferometer was used for n determination, whereby a margin area of 10 % of diameter resp. edge length (max. 10 mm) was not taken into consideration.
  5. Lower tolerances available upon request.
  6. Not valid for drawn products.
  7. Lower values with respect to product size and processing available upon request.
  8. Perpendicular to functional direction.

*) By reason of the measurement accuracy maximum values. Real measuring values are smaller. (on inquiry)

Quartz glass SQ, Silux
Technical Glass
Further to SiO2 are impurities of 0.27 – 38 ppm
Multi-component mixture with trace elements
Applications for the semi-conductor, medical and biotech industries
Quartz glass SQ
Optical Glass BK 7
160 – 4000 nm
290 -2800 nm
UV and IR optics, resistant to radio active rays, excimer laser proo
Quartz glass SILUX
Technical Glass Borosilicate Glass
Wafer boats, process chambers for high temperature applications for the semiconductor industry
Quartz glass SQ
Optical Glass BK 7
160 – 4000 nm
290 -2800 nm
UV and IR optics, resistant to radio active rays, excimer laser proo

The combination of high purity, outstanding transmission and high temperature ratings, make the development of innovative products possible at SICO.

Examples are:

  • Components used in the automotive industry (specifically for partially transparent engines), for the research and development of combustion processes.
  • Development of quartz glass moulds for the production foam-aluminum (used as “crash zones” in the automotive industry.
  • Various products for the semiconductor industry: wafer boats, process chambers, as well as mounting and supporting elements in numerous dimensions.

SILUX® – glasses are produced by flame fusing chemically and physically pre-treated and selected natural quartz powder. Grades SILUX®4 and SILUX®5 differ with regard to the content of bubbles and inclusions.

SILUX®4 has insignificant content of bubbles and inclusions. Predominantly used for optical components without high demands on optical quality for example windows, as material for rods used for support parts, or protective devices in the semiconductor technology.

SILUX®5 has low content of bubbles and inclusions. This glass is mainly used for high temperature applications.

Out of this quartz we manufacture boats, tubes and process chambers or whatever the customer needs. Just order what you need at our office.

Fused silica and fused quartz are used to manufacture components widely used in the optical and semiconductor industry. 

Mostly the terms fused silica and fused quartz are not clearly distinguished. Fused silica is synthetic amorphous silicon dioxide of high purity. In our case it is produced by pyrolysis of silicontetrachloride (SiCl4) in a hydrogen-oxygen flame.

The raw material of fused quartz is a mineralogical product mined from the earth as natural quartz or from quartzite sand. It is then manufactured by fusing powdered crystal in a hydrogen-oxygen flame and selected to different qualities.

SICO supplies both types of quartz glass.
Fused silica grades SQ0 / SQ1 / SQ2
Fused quartz grades SILUX®4 and SILUX®5

SQ glasses are synthetic quartz glasses produced from high purity SiCl4 by the flame pyrolysis method. These glasses are free of bubbles and inclusions and distinguish to other glasses by good transmission in UV and visible spectral range. The sorts SQ0 – SQ2 are different regarding to homogeneity, laminas, inclusions and transmission in the deep UV range.

SQ0 is distinguished by high homogeneity. This means it is free of laminas and striae in all spatial directions (3-dimension free of laminas). Chiefly used in reproducing optics, for example as prisms and lenses of different shapes. SQ0 has an excellent resistance to high-energy radiation.

SQ1 is homogeneous in one spatial direction, this means that weak laminas may occur vertical to the functional direction. SQ1 is resistant to excimer-laser beams, free of fluorescence, free of bubbles and inclusions. Main use in reproducing optics, microelectronics (substrates, lenses) high-temperature environments and laser technique.

SQ2 is obtained by reshaping SQ1 glass thermal treatment. SQ2 has insignificant reduction of transmission in deep UV range. Primarily used for tubes and rods in microelectronics, for making glass-blowing products and for components with low demands on transmission in deep UV range.

SQ3 is synthetic fused silica of lower quality grade then SQ2. All typical parameter correspond to SQ2 grade, except homogeneity, laminas, striae and alteration of refraction.

SQ1 layer thicknesses 1 and 10 mm

Typical total transmission at 185nm with layer thickness of 10 mm =g > 80%.
Upon request measuring curves for the VUV-wavelength of 140nm are available. 


SQ2: Transmission for > 250nm identical to SQ0 and SQ1. Minimum internal transmission values for < 250nm indicated below.


SQ3: Transmission for > 250nm identical to SQ2.

SILUX® layer thickness 1 and 10mm