MENU

Silicon wafer enterprises grab the "crucible", and the photovoltaic industry chain highlights the "new bottleneck"

02/03/2023


Silicon wafer enterprises grab the "crucible", and the photovoltaic industry

chain highlights the "new bottleneck"

At present, the "bottleneck" in the photovoltaic industry chain is shifting from silicon materials to other links.

On February 23, according to the Silicon Industry Branch of the China Nonferrous Metals Industry Association, the silicon wafer end has fallen into a phased shortage, and the main reason for the restriction of its production is that the supply of quartz crucibles (and quartz sand) has been in short supply. The situation has largely affected the production capacity of specialized silicon wafer companies, causing some companies to be unable to operate at full capacity in the short term.

It is reported that, except for a few leading (silicon wafer) companies, most specialized companies report that quartz crucibles limit the output of crystal pulling. The main reason is that the production expansion progress of two overseas quartz sand suppliers is not as fast as expected, and the inner layer of the crucible must use imported quartz sand. Purchase quantity.

As of February 23, the mainstream prices of the national high-purity quartz sand market are as follows: the price of high-purity quartz sand for 4N5-grade photovoltaic quartz crucibles in Shandong is 50,000-70,000 yuan/ton, and the price of 4N5-grade photovoltaic quartz crucibles in Jiangsu is high The price of pure quartz sand is 50,000-70,000 yuan/ton. The price of quartz crucible high-purity quartz sand for photovoltaic use of Quartz Co., Ltd. is 90,000 to 100,000 yuan/ton for the outer layer of sand, 100,000 to 110,000 yuan/ton for the middle layer of sand, and 110,000 to 120,000 yuan/ton for the inner layer of sand . At the same time, the price of imported sand exceeded 140,000 yuan/ton.

The trend of large-scale silicon wafers is clear, and the size upgrades are accelerating. Under the trend of large size, the quality requirements of large-size quartz crucibles for high-purity sand will also increase accordingly.

On the one hand, the larger the size of the quartz crucible, the larger the contact area between the inner surface of the crucible and the silicon liquid, and thus higher requirements for the quality stability and consistency of the sand in the inner layer of the crucible. Otherwise, the crystallization of silicon (whole rod rate , crystallization rate, heating time, direct processing cost, etc.) and the quality of monocrystalline silicon (perforated sheet, black chip, etc.) will have a certain negative impact.

For example, the consistency of high-purity quartz sand determines the stability of the crystal pulling process route. If the reserves of a quartz ore are not very large, or the quality of the ore varies greatly, the purity of the produced quartz sand, gas-liquid inclusions, etc. It is difficult to form a consistent quality, and then a certain area of the inner surface of the quartz crucible used for production may be the first to devitrify or cause the crucible to break. Therefore, the larger the size of the crucible, the higher the risk of the inner surface, so the higher the quality requirements for the quartz sand.

Similarly, in the process of using large-sized quartz crucibles to hold molten silicon liquid and pulling crystals, the more silicon liquid that needs to be melted per unit time, the greater the heating power of the thermal field required, thus improving the high-temperature resistance of high-purity sand. Make higher demands. In addition, in an environment with a higher temperature, the crystallization speed of impurities will be accelerated, thereby affecting the crystal pulling efficiency. Therefore, the large-sized crucible also puts forward higher requirements on the high-temperature resistance, purity, and strength of the quartz sand as a whole.

Therefore, large-sized quartz crucibles have higher requirements on the quality of high-purity quartz sand, such as purity, gas-liquid inclusions, particle size distribution, and consistency. The scarcity of high-quality quartz sand will also affect the production cost of downstream silicon wafer companies. and quality differences.

The scarcity of high-quality quartz sand may restrict the production of large-size quartz crucibles. In terms of the product quality of raw material high-purity quartz sand, Unimin/TQC is currently the first echelon with the best product quality, and high-purity sand is mainly used in the inner layer of crucibles; while Quartz shares benefit from its own purification technology progress and reserves Good-quality ore sources have become the second echelon, and gradually become the first choice for domestic alternatives to inner and middle sands; other small domestic enterprises are the third echelon, and the quality of quartz sand is inferior and the outer layer is the main one, and the price is also low.

Considering that if the expansion progress of overseas Unimin and TQC is not as expected, the gap in the inner sand layer will be further enlarged in 2023, or the production quality of large-sized quartz crucibles in 2023 may be restricted to a certain extent. The quality of large-sized crucibles produced by high-purity quartz sand may affect the production cost of silicon wafer enterprises in various ways.

High-purity sand has a major impact on downstream secondary costs and product quality. In order to ensure their own cost and quality leadership, downstream companies will most likely increase their competition for high-quality quartz sand.

It is reported that at present, more than 70% of the quartz sand is locked by leading silicon wafer enterprises in the form of locking quantity and price, and the proportion of imported high-purity quartz sand that is actually circulated in the market is only about 30%, which has led to a rise in the price of domestic quartz sand. , At present, the price of a domestic leading quartz sand is as high as 149 yuan per kilogram.

Due to the foreseeable shortage of quartz sand and quartz crucibles in the future, leading monocrystalline companies will start hoarding high-purity quartz sand from the first half of 2021, and most monocrystalline silicon wafer companies will also start hoarding high-purity quartz sand and monocrystalline crucibles from 2022. This further exacerbates the shortage of high-purity quartz sand and single crystal crucibles. It is said that the periodical shortage of quartz crucibles has caused some enterprises to be unable to produce at full capacity in the short term, and has also caused a shortage of silicon wafers in the current photovoltaic market, resulting in a slight increase in the price of silicon wafers.


OTHER NEWS

INQUIRY

Name is required!

Mail address required!

Mail address must be valid!

Click it

Message field is empty!

BackBack to Top