# Crystal-growth components

Graphite heaters, crucibles, shields and supports for silicon and SiC crystal growth.

Family: Semiconductor applications

## Description
The **place** is a Czochralski puller or an SiC growth furnace. The **application** is the set of graphite hot-zone parts: heaters, crucibles or supports, shields and shaped pieces.

These parts are not heat-treatment liners and not hot-pressing dies. Selection follows purity and the thermal geometry of the growth tool, not the hardening of metal parts.

ESGRAF machines components to drawing from high-purity isostatic or extruded graphite. When chamber insulation is required, [carbon felts](/en/materials/felts-foils-packing-others/soft) and [CFC panels](/en/materials/felts-foils-packing-others/cfc-panels) are also reviewed. State equipment type, temperature, atmosphere and drawing to quote.

## Processes
- Czochralski silicon growth
- SiC growth by PVT
- Hot-zone heating and shielding

## Challenges
- Crystal contamination from graphite impurities
- Heater failure from geometry or atmosphere
- Loss of thermal uniformity when replacing parts

## Advantages
- High-purity grades for vacuum
- Heaters, shields and supports machined to drawing
- Geometry copied from a used part

## Limitations
- Oxidation in air at high temperature
- Grade resistivity must match the heater electrical design
- A heat-treatment furnace grade does not replace a high-purity grade without review

- [Applications](https://esgraf.com/en/applications)
- [Alternate](https://esgraf.com/aplicaciones/semiconductores-crecimiento-cristal)