Zinc sulfide crystal (ZnS) is an important infrared optical material with growing market demand

Zinc sulfide, chemical formula ZnS, is an inorganic compound that appears as white or slightly yellow crystal powder. It is insoluble in water but soluble in acid. It changes color when exposed to light and is easily oxidized in humid air. Zinc sulfide has a large band gap and can be used as a semiconductor material; adding an activator to emit fluorescence of different colors can be used as a fluorescent material; it has good optical properties in the infrared region and can be used as an infrared transmitting material.

The zinc sulfide preparation process mainly includes solution method, hot press forming method, chemical vapor deposition method, etc. The solution method can prepare zinc sulfide for fluorescent materials; the hot pressing method can prepare zinc sulfide for optical materials; the chemical vapor deposition method combined with a high-pressure single crystal furnace can grow zinc sulfide crystals. Among them, the solution method has the advantages of large output and low cost, and the crystals grown by the chemical vapor deposition method have the advantages of fewer defects.

Zinc sulfide crystal grown by chemical vapor deposition (CVD) is a white solid crystal with relatively stable properties. Zinc sulfide crystal can be used as a detector material. Due to poor transparency, it cannot be used to detect gamma rays, but it has high efficiency in detecting alpha rays and heavy particles; zinc sulfide crystal is doped with silver (Ag), copper (Cu), and manganese (Mn). As an activator, it can emit fluorescence of different colors under light irradiation and can be used to manufacture luminous tubes, fluorescent screens, etc.

Among optical materials, infrared optical materials are more common. The segmented products of infrared optical materials mainly include zinc sulfide crystal, single crystal germanium, gallium arsenide, sapphire, etc. Among them, zinc sulfide crystal is the most common. According to the “China Zinc Sulfide Crystal (ZnS) Industry Market In-depth Research and Development Prospects Forecast Report 2023-2028” released by the Industrial Research CenterIt shows that zinc sulfide crystal has high purity, moderate density, high hardness, uniform refractive index, good consistency, easy processing, low price, good optical performance in the mid-infrared and far-infrared regions, and strong adaptability in harsh environments, so There is huge room for development in the military industry, and its large-diameter products can be used to make infrared detector windows.

From 2018 to 2022, the average annual compound growth rate of my country’s infrared detector market size is approximately 15.6%. After continuous development, the application field of infrared detectors in my country has gradually expanded from military to civilian use. The broadening of the application scope has promoted the increasing number of infrared detector-related enterprises in my country and the continuous improvement of technological levels. The performance gap between the products produced by advanced enterprises and imported products has continued to narrow. The market localization rate continues to increase. Against this background, my country’s demand for infrared optical materials continues to grow, which is beneficial to the development of the zinc sulfide crystal industry.

Industry analysts said that in overseas markets, the main zinc sulfide crystal manufacturers include II-VI Incorporated of the United States, Sydor Optics of the United States, British Crystran, German Hellma, German Korth Kristalle, Russian Crystal techno, etc.; in the Chinese market, the main zinc sulfide crystal manufacturers include Taizhou Ates Optical Materials Co., Ltd., Qinhuangdao Intrinsic Crystal Technology Co., Ltd., etc.