PVT Silicon Carbide Crystal Furnace

Our company's PVT crystal furnace is an important equipment for growing crystals such as silicon carbide, mainly used for the growth of large-size single-crystal silicon carbide. This crystal furnace uses the physical vapor transport (PVT) method to optimize the relevant growth process parameters or equipment structure through simulation.

The PVT crystal furnace has many technical features, including precise control of furnace pressure, crucible movement and rotation, seed crystal position, and temperature field distribution. It uses advanced control technology, dynamic sealing technology, special structural design, and high-temperature infrared measurement technology to ensure accurate temperature control and small error. In addition, the PVT crystal furnace can also optimize the thermal field through simulation to improve the efficiency and quality of crystal growth.

Purchase Information:

If you are interested in our PVT silicon carbide crystal furnace, please contact us for more information and quotation.

Tel: 86 159 3625 3205

Email: zerlinda@zztainuo.com

Contact person: Zerlinda

WeChat: 86 159 3625 3205

Specifications

Main accessories：

Application

• Power electronics

• Aerospace

• Biomedical materials

• Perovskite photovoltaic materials

•        Semiconductor materials

•        Nuclear energy

Application case "Growing silicon carbide single crystals through PVT crystal furnace"

The experimental steps for growing silicon carbide (SiC) single crystals in the PVT method (physical vapor transport method) usually include the following stages:

1. Preparation stage

Raw material preparation: Select high-purity silicon carbide powder as the source material to ensure the purity of the finished crystal. The source material is usually placed in a graphite crucible.

Seed crystal preparation: Select high-quality SiC seed crystals that meet the growth direction requirements. The seed crystals should have a smooth surface and no impurities or cracks.

Equipment inspection: Ensure that all systems of the PVT crystal growth furnace (heating, temperature control, vacuum control, etc.) are working properly. The furnace chamber should be thoroughly cleaned to avoid impurities affecting the crystal quality.

2. Furnace loading

Place the seed crystal and silicon carbide source material in the appropriate positions of the graphite crucible respectively. The seed crystal is usually placed on the top of the crucible, while the silicon carbide source material is placed at the bottom of the crucible.

After the crucible is loaded, it is placed in the cavity of the crystal growth furnace, and ensure that the cavity is well sealed to prevent air leakage.

3. Vacuuming and gas replacement

Close the furnace door and start the vacuum pump to evacuate the furnace chamber to a low pressure (usually between a few millibars and tens of millibars).

Inert gas (such as argon) can be introduced as needed to stabilize the furnace environment and prevent material oxidation.

4. Heating and stabilizing temperature

Gradually increase the temperature to between 2000°C and 2400°C, which is suitable for the sublimation and gas phase transport of SiC. During the temperature rise process, the temperature gradient should be stable (such as the upper temperature is slightly higher than the lower temperature to promote gas phase transport).

The temperature difference is usually set between 20°C and 100°C to ensure that the material evaporates from the source area and deposits on the seed crystal surface. The high temperature end is responsible for the sublimation of the silicon carbide source, and the low temperature end is the seed crystal area.

5. Crystal growth process

Under appropriate temperature and pressure conditions, silicon carbide begins to move in the gas phase and deposits on the surface of the seed crystal. Depending on the set growth rate and crystal size, the growth process usually lasts for several days to weeks.

Maintain a stable temperature gradient and vacuum state to ensure that silicon carbide in the gas phase is smoothly and evenly deposited on the seed crystal to generate a single crystal structure.

6. Cooling process

When the growth reaches the predetermined thickness or time, the temperature in the furnace is gradually reduced. In order to avoid cracks or internal stress in the crystal, it is usually cooled slowly (usually in a gradient).

Before the furnace temperature drops to a safe temperature (such as below 200°C), it is not advisable to open the furnace quickly to prevent thermal shock from damaging the crystal.

7. Take out the crystal

After the temperature in the furnace drops to room temperature, open the furnace door and carefully take out the graphite crucible.

Take out the SiC single crystal from the crucible. If there is slight adhesion, it can be carefully removed by mechanical separation to protect the crystal surface from damage.

8. Subsequent processing and quality inspection

The removed SiC single crystal is subjected to subsequent processing, such as cutting and polishing, to obtain wafers that meet the requirements.

Use X-ray diffraction (XRD), Raman spectroscopy analysis and other means to detect the quality and purity of the crystal, and evaluate the integrity of the crystal structure.

Through strict experimental step control and precise parameter setting, the PVT method can grow high-quality silicon carbide single crystals. This method is widely used in the production of SiC crystals required for power semiconductors and other high-demand electronic devices.