Electronic-grade polyacrylic acid (PAA): a “nanoscale cleaner” for chip manufacturing”

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Electronic-grade polyacrylic acid (PAA): A \"nanoscale cleaner\" in chip manufacturing I. Product definition 1. Electronic-grade polyacrylic acid (PAA) is an aqueous dispersant obtained through the homopolymerization of acrylic acid as a monomer; it exhibits strong resistance to redeposition during processes such as grinding, polishing, and cleaning, and thus serves as a key material for semiconductor cleaning. What sets it apart from industrial-grade PAA is its extreme purity and customized molecular structure; it is a high-purity product suitable as a cleaning agent in the electronics industry. 2. Physical properties: It appears as a colorless to pale yellow transparent liquid, with a solid content of ≥15.0%. Its metal ion content is extremely low; it can be customized to the ppb level to meet the requirements for nanoscale cleanliness. 3. Core performance: Its molecular chain contains a large number of carboxyl functional groups, granting it excellent chelating capabilities; it can form stable complexes with metal ions. During semiconductor cleaning, it effectively disperses polishing particles, captures metal ions, and prevents the reattachment of contaminants through three mechanisms: electrostatic repulsion, steric hindrance, and chelation. It is a key functional additive that ensures an atomically clean surface on wafers. II. Application Areas 1. Semiconductor grinding: Used to remove the residual grinding particles and contaminants on the wafer surface after chemical mechanical polishing. 2. Semiconductor polishing: Used as a dispersant in the polishing process to improve the uniformity of the polishing solution and the efficiency of cleaning. 3. Semiconductor cleaning: Used for cleaning in key steps such as after wet etching and after resist removal, to minimize cross-contamination between different manufacturing processes. 4. Emerging application areas: Used for cleaning in fields such as advanced packaging (e.g., 2.5D/3D), Micro LED, and silicon carbide power semiconductors. III. Production Process and Technical Sources 1. The industrial production of electronic-grade PAA mainly relies on the solution polymerization method. Polymerization is carried out in an aqueous solution at 60–100°C, using acrylic acid as the monomer and persulfate as the initiator. It is usually carried out in a continuous reaction system with static mixers in series, and through multiple stages of treatment using ultrafiltration, nanofiltration, and ion exchange resins to remove residual monomers, oligomers, and metal ions; once the standards are met, it is filled in an electron-grade clean environment. The entire production process imposes extremely strict requirements on the purity of raw materials, water quality, reaction temperature, and subsequent purification steps. 2. The technology comes primarily from German BASF and Japanese East Asia Synthesis; these companies hold the core patents for high-purity polymerization and precise purification, thus monopolizing the high-end market. In China, companies such as Taihe Technology have independently developed technologies for continuous polymerization, online purification, and precise control of molecular weight, achieving product purity on par with international standards ； IV. Major Manufacturers and Production Capacities 1. International Manufacturers (1) BASF in Germany: Production capacity of around 1,200 tons per year. (2) East Asia Synthesis in Japan: Production capacity of around 800 tons per year. (3) Dow Chemical in the United States: Production capacity of around 500 tons per year. 2. Domestic Manufacturers (1) Taihe Technology: A leading domestic manufacturer; its current production capacity for electronic-grade PAA is 300 tons per year, with plans to increase this to 800 tons per year by 2027. (2) Shandong Luguang Chemical and Jiangsu Sanmu Group: Each have a production capacity of 100–200 tons per year. (3) There are many other manufacturers of polyacrylic acid (PAA), including those producing industrial-grade PAA or PAA used as battery binders; such companies include Huitian New Materials, Satellite Chemical, and Blue Sea Blackstone. Among them, Satellite Chemical is the leader in China’s production capacity for acrylic acid and its downstream products, while Huitian New Materials holds a significant advantage in the adhesive industry. Although PAA used as a binder for battery negative electrodes and PAA used for cleaning electronic-grade semiconductors have different requirements in terms of purity, molecular weight, and other parameters, there are technical similarities between them.