Phosphorus oxychloride SOLAR GRADE (POCl₃)

The production of semiconductors using POCl₃ is carried out during the process of doping silicon, that is, introducing phosphorus atoms into the structure of silicon, which changes its electrical properties, increasing n-type conductivity. The popularity of phosphorus oxychloride in the n-type emitter production is attributed to its low cost, good stability, relative simplicity of the process, good control, homogeneity, and its high efficiency. It has replaced, for example, solid P₂O₅ in this process.

POCl₃ SOLAR GRADE is also used in the manufacture of optical fibres. The introduction of a controlled amount of the dopant into the structure of the glass allows it to change its optical properties (e.g., light transmission in a specific spectral range). In addition, the deposition of a phosphorus layer on the glass surface can be used to change optical properties such as reflection, transmission, or absorption of light.

POCl₃ SOLAR GRADE is sold in specialised bubblers (1 L), which are prepared for direct use in the production of the aforementioned semiconductors, allowing the product to be used quickly, conveniently, and safely, thereby minimising-costs and the risk of product deterioration. The bubblers offered can be used in both diffusion atmosphere and low-pressure furnaces. 

The product is also available in 20 L pressure vessels made of stainless steel, lined with an inner coating of thermoplastic fluoropolymer - ETFE and a dip tube made of PFA. Supplied in 20 L tanks, POCl₃ Solar Grade allows for much more efficient operation in the production of solar photovoltaic panels, among others, by reducing the frequency of 1 L bubblers exchanges, thus eliminating furnace downtime, which in turn has a positive effect on the stability of the production process itself by reducing temperature fluctuations. In addition, the reduced number of 1 L bubblers exchanges brings environmental and financial benefits, through lower POCl₃ losses, reduced transport and logistics costs, no need to store smaller unit packs, and less frequent handling, resulting in lower costs and increased operational safety.

Physical and chemical properties:

Phosphorus oxychloride (POCl₃) is a colourless liquid with a pungent, very distinctive odour. It hydrolyses very easily which is accompanied by the release of fumes, and its products are phosphoric acid and hydrogen chloride.

The phosphorus oxychloride reacts very violently with water. Due to the high exothermicity of the process and the resulting release of large quantities of suffocating hydrogen chloride, transport, and storage should be in tightly sealed containers protected from moisture or flooding. 

The product is highly corrosive, which affects the type of packaging in which it should be stored and transported. The packaging should be made of a suitable material, preferably a certain quality of steel, Teflon, or glass. It is very important to use personal protective equipment when working with phosphorus oxychloride, as it causes burns when it comes into contact with the skin. The product should be protected from both excessively high temperatures (due to the high vapour pressure of the substance), and excessively low temperatures (as it starts to solidify at temperatures below 1°C).