The tubular PECVD furnace (plasma enhanced chemical vapor deposition tubular furnace) is a commonly used equipment in the manufacturing of photovoltaic cells. Its core function is to deposit silicon nitride (SiNx) anti reflection films on the surface of crystalline silicon solar cells through plasma assisted chemical vapor deposition technology. Let's take a detailed look at the applications of tubular PECVD electric furnaces used in the photovoltaic industry below!

Tube type PECVD electric furnace (click on the image to view product details)

1. Core function: Efficient deposition of high-performance thin films
The tubular PECVD furnace (plasma enhanced chemical vapor deposition tubular furnace) is a commonly used equipment in the manufacturing of photovoltaic cells. Its core function is to deposit silicon nitride (SiNx) anti reflection films on the surface of crystalline silicon solar cells through plasma assisted chemical vapor deposition technology. This film enhances battery performance through the following mechanisms:
Optical optimization: By adjusting the thickness and refractive index of SiNx thin film, utilizing the principle of light interference to reduce surface reflection, more light enters the interior of the battery, and the photoelectric conversion efficiency is improved by 1% -2%.
Surface passivation: The hydrogen element in SiNx can passivate lattice defects (such as dislocations and dangling bonds) on the silicon surface, reduce carrier recombination, and increase open circuit voltage and short-circuit current.
Mechanical protection: The film serves as an encapsulation layer to prevent contamination or mechanical damage to the silicon wafer during subsequent processes.

2. Technical advantages: low temperature, high efficiency, precise control
Low temperature sedimentation process
PECVD technology uses plasma to excite reactive gases, reducing the deposition temperature to 400-500 ℃ (traditional CVD requires above 800 ℃), avoiding thermal damage to silicon wafers and substrate materials at high temperatures, especially suitable for the manufacturing of thin and flexible batteries.
High sedimentation rate and uniformity
Radio frequency glow technology: By generating high-density plasma through high-frequency electric fields (such as 13.56MHz), the reaction rate is greatly improved, and the deposition rate can reach 10-50nm/min.
Uniformity control: Adopting multi-point RF feeding, uniform gas path distribution, and intelligent temperature control system to ensure film thickness uniformity of ≤± 5%, meeting the needs of large-scale production.
Material diversity
It can deposit various dielectric films such as SiO ₂, Si ∝ N ₄, Al ₂ O ∝, etc., expanding the design space of battery structures (such as stacked batteries and back passivated batteries).
Environmental Protection and Energy Conservation
Low temperature technology reduces energy consumption while avoiding the emission of harmful substances at high temperatures, which is in line with the trend of green manufacturing in the photovoltaic industry.

3. Equipment structure and key parameters
typical configuration
Heating system: single temperature zone or multi temperature zone resistance furnace, with a maximum temperature of 1200 ℃ and a temperature control accuracy of ± 1 ℃.
Vacuum system: a combination of molecular pump and mechanical pump, with a maximum vacuum degree of ≤ 10 ⁻ Pa, meeting the requirements of high-purity thin film deposition.
RF power supply: supports precise control of plasma density.
Gas system: Multi channel mass flow meter (MFC), supporting 1-6 gas mixtures.
process control
Temperature curve programming: supports temperature rise and fall programs of more than 30 segments, adapting to the process requirements of different film materials.
Pressure control: Positive pressure range -100kPa to 100kPa, supporting low-pressure to atmospheric pressure process switching.
Intelligent monitoring: equipped with functions such as overheating alarm, overcurrent protection, and disconnection prompt to ensure stable operation of the equipment.

4. Application scenarios and market trends
Mainstream applications
PERC cell: By depositing a backside Al ₂ O ∝/SiNx laminated film, the dual functions of backside passivation and anti reflection are achieved.
TOPCon battery: Utilizing PECVD deposition of tunneling oxide layer (SiO ₂) and doped polycrystalline silicon layer to construct efficient carrier transport channels.
HJT battery: Deposition of intrinsic amorphous silicon (i-a-Si: H) at the interface of amorphous silicon/crystalline silicon heterojunction to optimize the density of interface defect states.

Rotating and tilting tubular PECVD electric furnace (click on the image to view product details)

5. Summary: Industry value of tubular PECVD electric furnace
The tubular PECVD electric furnace has become a widely used equipment in photovoltaic cell manufacturing due to its core advantages of low temperature, high efficiency, precision, and environmental protection. With the increasing market share of N-type batteries (TOPCon, HJT), their requirements for film quality will further promote the development of PECVD technology towards high uniformity, high deposition rate, and low defect density. In the future, equipment manufacturers need to continue innovating to meet the long-term demand for cost reduction and efficiency improvement in the photovoltaic industry.Click to learn more PECVD devices! Or click on online customer service to learn more about product information!