A vertical tube furnace is a hot-wall heating device with vertically arranged tubes. Its structural design centers around a vertical tube, typically made of annealed quartz. Surrounded by a multi-zone heater (typically divided into three or four zones), the furnace maintains uniform temperature distribution through convection and radiation. Gas enters the furnace tube from the front (near the door), flows through a vertically positioned sample boat, and then is exhausted through a vacuum system or exhaust system, creating a closed or controlled atmosphere for the reaction.

The vertical layout offers key advantages:

The sample boat can be stably positioned within the furnace tube by gravity or mechanical means, reducing the uneven thermal gradients encountered with horizontal placement.

The vertical structure facilitates integration with automated loading and unloading systems, making it particularly suitable for mass production.

The sealed bottom of the furnace tube facilitates high vacuum or inert atmosphere control, minimizing the risk of gas leaks.

Core Performance Advantages

Heat Field Uniformity: The vertical layout reduces the interference of gas convection on temperature distribution. Combined with multi-zone heating technology, the axial temperature difference within the furnace tube can be controlled within ±3°C, making it suitable for temperature-sensitive processes such as thin film deposition and crystal growth.

Process Compatibility: Compatible with semiconductor processes such as LPCVD (low-pressure chemical vapor deposition) and oxidation diffusion, it is particularly suitable for applications requiring vertical substrate placement (such as batch processing of silicon wafers and ceramic substrates).

Improved Safety: The furnace door of the vertical furnace tube is typically located at the top or bottom, avoiding direct exposure to high-temperature areas during operation and reducing the risk of burns. Furthermore, the vertical structure facilitates the integration of safety devices such as over-temperature alarms and gas leak detection.

Typical Applications:

Semiconductor Manufacturing:

In integrated circuit production, it is used for oxidation and doping processes in silicon wafers. For example, by introducing oxygen and chlorine gases, uniform silicon dioxide thin films are grown on the surface of silicon wafers within the vertical furnace tube, with film thickness uniformity controlled within ±2%.

New Material Research and Development:

It is suitable for the high-temperature synthesis of nanomaterials (such as carbon nanotubes and two-dimensional materials). Vertical furnace tubes provide a stable temperature environment and gas flow conditions, promoting directional growth of materials on the substrate surface.

Ceramics and Powder Metallurgy
Used for sintering ceramic powders or heat treating metal powders, the vertical layout facilitates continuous feeding and improves production efficiency. For example, in the preparation of magnetic materials, the controlled atmosphere sintering of vertical furnace tubes can reduce material oxidation and improve magnetic properties.