The full portfolio material for semiconductor applications

A selection of large tubes and hollows as used for semiconductor applications

Brand Overview

Heraeus Conamic manufactures fused quartz and silica products by utilizing different fusion technologies. The material grades and available dimensions are each optimized for their final application.

The electrically fused quartz products are the benchmark for high thermal stability while maintaining superior purity and material homogeneity. Whereas the synthetic fused silica products can offer outstanding synthetic grade chemical purity. Both product ranges are available in full portfolio by geometry and size united under the Heraeus Conamic brand HSQ®.

HSQ® Product Portfolio

In the following you will find an overview of the different HSQ® material grades that Heraeus Conamic can provide, each highlighted by the relevant features in this application segment.

Material Grade

Production Type



HSQ® 100



High thermal stability, cost-efficient solution due to single step electrical fusion process, high chemical purity

HSQ® 300


Semiconductor, solar and industrial

High thermal stability, very high chemical purity, low bubble and inclusion content

HSQ® 330 (S)


High- and super-high purity semiconductor

High thermal stability, very high chemical purity especially with tighter limits for alkaline and metal contaminations, low bubble and inclusion content

HSQ® 400


Industrial, solar, semiconductor

Very high thermal stability due to chemical stabilization layer, high chemical purity, low bubble and inclusion content

HSQ® 700


Semiconductor, industrial

High thermal stability, very high chemical purity especially low concentration of alkaline metals, low bubble and inclusion content

HSQ® 900


Leading edge semiconductor applications

Outstanding synthetic grade chemical purity, almost bubble and inclusion free, available in different geometries



Leading edge semiconductor applications

Outstanding synthetic grade chemical purity, most elements below detection limit, available in different geometries

Fusion Methods of HSQ®


The electric fusion is the most commonly used melting process for manufacturing quartz glass. The name is derived from the method of heating up the material, in this case: an electric current is heating a resistive heater, hence the name "Electrical Fusion".

The benefits of Electrical Fusion is the lower OH-content, compared to other fusion methods. Typical values are in the range of <30ppm. As the OH-content is directly influencing the maximum possible working temperature for the fused quartz, Electrical Fused quartz is especially suitable for high temperature applications.

Electrical Fusion can be used in both – continuous fusion or batch/boule fusion and therefore offer a large variety of geometries, shapes and dimensions.


The main difference between so-called natural quartz material and synthetic quartz material, is the used raw material. While natural quartz is produced from quartz sand minded in a quartz mine, synthetic quartz is using chemical gases as raw material. Such chemical gas containing a silicon source will be put into reaction with oxygen forming pure silicon dioxide. The purity achievable by this manufacturing procedure is magnitudes higher compared to natural quartz.

Synthetic fused quartz (sometimes also called fused silica) is the ideal choice for most demanding applications in which purity of the process environment is of the essence.

Our synthetic fused silica materials are available in the same portfolio of shape, geometry and dimensions as our electrical fused material.

Benefits of HSQ®

  • Addressing key material challenges

    • Highest thermal stability (electrically fused quartz)
    • Outstanding synthetic grade purity (synthetic fused silica)
    • Low levels of inclusions and bubbles
  • Providing consistency for centuries

    • In-house material purification
    • > 100 years of experience
    • Full portfolio in shape and size

Fields of Applications

  • Process tubes for single and batch processes
  • Top plates for outer tubes
  • Boats for batch furnaces


  • Brochure: Clear Fused Silica for Semiconductor Manufacturing

  • Data Sheet: HSQ®-T