Electronic Grade Cerium Ammonium Nitrate

Rare Earth Nitrates

1. Basic Product Overview

Electronic Grade Cerium Ammonium Nitrate, often referred to as Electronic Grade CAN, is a high-purity variant of cerium(IV)-ammonium nitrate with the chemical formula (NH₄)₂Ce(NO₃)₆, specifically engineered to meet the stringent requirements of the electronics industry. Unlike reagent grade or technical grade CAN, this grade prioritizes ultra-low levels of trace contaminants, as even minute impurities can disrupt the performance and reliability of electronic components. With a typical purity of ≥99.99% —and in some advanced formulations reaching 99.999% or higher—Electronic Grade CAN is free from harmful trace elements such as heavy metals (e.g., lead, cadmium, mercury), transition metals (e.g., iron, copper, nickel), and anions (e.g., chloride, sulfate, phosphate) that could cause defects in semiconductor manufacturing, thin-film deposition, or other precision electronic processes.

At standard temperature and pressure (STP), Electronic Grade CAN retains the bright orange-red crystalline solid appearance of other CAN grades, often milled into fine, uniform powder to ensure consistent dispersion in processing solutions. Its distinct color, derived from the cerium(IV) ion (Ce⁴⁺), remains a useful visual identifier, but the key differentiator lies in its impurity profile: rigorous purification processes reduce trace metal concentrations to parts per billion (ppb) levels, making it suitable for applications where material purity directly impacts device functionality, such as in the production of semiconductors, optoelectronic components, and advanced electronic materials.

2. Physical and Chemical Properties

The physical and chemical properties of Electronic Grade CAN build on those of standard CAN but are refined to eliminate variability caused by impurities, ensuring consistent performance in precision electronic applications.

Physical Properties

In terms of physical appearance, Electronic Grade CAN presents as a bright orange-red crystalline solid, typically processed into a fine, homogeneous powder with a controlled particle size distribution—often ranging from 50 to 150 mesh—to facilitate easy dissolution in high-purity solvents (e.g., ultra-pure water, electronic-grade acetonitrile). Its molecular weight remains 548.22 g/mol, consistent with other CAN grades, but it exhibits enhanced solubility characteristics in ultra-pure water: at 20°C, it dissolves at a rate of approximately 141 g per 100 mL of ultra-pure water, with no visible undissolved particles or residue, a critical trait for preparing contamination-free process solutions. The bulk density of its powdered form is tightly controlled at 1.87 ± 0.02 g/cm³ to ensure uniform handling and dosing in manufacturing processes. Additionally, Electronic Grade CAN has moderate hygroscopicity, but unlike lower-grade variants, it is processed with minimal residual moisture (typically<0.1%) to="" prevent="" clumping="" and="" maintain="" purity="" during="" exposure="" high="" humidity="">50%) can still cause clumping, which is why strict storage conditions are required.

Chemical Properties

The defining chemical trait of Electronic Grade CAN is its strong oxidizing ability, attributed to the Ce⁴⁺ ion (standard reduction potential: Ce⁴⁺/Ce³⁺ = +1.61 V in 1 M electronic-grade nitric acid), identical to other CAN grades. However, its chemical behavior is distinguished by exceptional stability and consistency, as impurities that could interfere with redox reactions (e.g., trace Fe²⁺, which might prematurely reduce Ce⁴⁺) are nearly absent.

Key chemical behaviors of Electronic Grade CAN include acid dependence, redox reactivity, and thermal decomposition—all optimized for electronic applications. For acid dependence, it is stable only in acidic solutions with a pH below 2, and it is typically prepared in electronic-grade dilute nitric acid (HNO₃) to maintain stability and avoid hydrolysis of Ce⁴⁺ into insoluble cerium(IV) hydroxides (e.g., CeO₂·nH₂O). This is crucial in electronic processes, where even small amounts of precipitate could contaminate wafers or thin films. In terms of redox reactions, its reaction with reducing agents (e.g., high-purity alcohols, semiconductor-grade metal ions) is highly predictable, with a sharp color change from orange-red to colorless as Ce⁴⁺ is reduced to Ce³⁺. This predictability is essential for processes like selective etching, where precise control of oxidation reactions is required. Regarding thermal decomposition, Electronic Grade CAN decomposes progressively at temperatures above 107°C, following the same pathway as other grades: initial decomposition releases high-purity ammonium nitrate (NH₄NO₃) fumes, followed by cerium(III) nitrate [Ce(NO₃)₃] and nitrogen oxides (NOₓ) at >200°C, and finally cerium oxide (CeO₂) above 300°C. The resulting CeO₂ is of ultra-high purity (>99.99%), making it suitable for use as a dielectric material or catalyst in electronic devices.

3. Manufacturing Process

The manufacturing process of Electronic Grade CAN is far more rigorous than that of reagent or technical grade, with additional purification steps to achieve ultra-low impurity levels. It still begins with rare earth ore processing but incorporates advanced separation and purification technologies to meet electronic industry standards.

Step 1: Ore Digestion and Initial Purification

The process starts with high-purity monazite or bastnäsite ore—selected for low initial levels of radioactive thorium (Th) and heavy metals. The ore is crushed into fine particles and treated with electronic-grade concentrated sulfuric acid (H₂SO₄) at 200–300°C in a contamination-controlled environment. This digestion step converts insoluble Rare Earth Oxides into soluble Rare Earth Sulfates (e.g., Ce₂(SO₄)₃), while impurities like silica (SiO₂) and thorium are removed as precipitates via high-speed centrifugation and ultra-filtration (using 0.1 μm membranes) to ensure complete separation.

Step 2: Cerium Oxidation and Pre-Purification

The resulting rare earth sulfate solution is adjusted to neutral pH using electronic-grade ammonium hydroxide (NH₄OH), causing Rare Earth Hydroxides to precipitate. The precipitate is dissolved in electronic-grade nitric acid to form a mixed rare earth nitrate solution, which then undergoes solvent extraction using high-purity extractants (e.g., tributyl phosphate) to separate cerium from other rare earth elements (e.g., lanthanum, neodymium). This step reduces non-cerium rare earth impurities to<10 ppb. Next, Ce³⁺ is oxidized to Ce⁴⁺ using electronic-grade hydrogen peroxide (H₂O₂) under acidic conditions—chlorine gas is avoided here to prevent chloride contamination—and the solution is filtered again to remove any oxidation byproducts.

Step 3: Ultra-Purification via Ion Exchange and Crystallization

This is the most critical step for achieving electronic-grade purity. The oxidized cerium nitrate solution is passed through a series of ion exchange resins (e.g., chelating resins) tailored to remove trace metal ions (e.g., Fe, Cu, Ni, Pb) to ppb levels. The solution is then concentrated under vacuum at low temperatures (40–50°C) to avoid thermal degradation and impurities from atmospheric exposure. Ammonium nitrate (NH₄NO₃) of electronic grade is added to the concentrated solution, initiating crystallization of (NH₄)₂Ce(NO₃)₆. The crystals are grown slowly in a controlled environment to minimize inclusion of impurities, then separated via vacuum filtration and washed repeatedly with ultra-pure cold water (1–5°C) to remove residual ammonium nitrate and any surface contaminants.

Step 4: Drying, Milling, and Quality Control

The wet CAN crystals are dried in a Class 100 cleanroom (to prevent airborne contamination) at 40–60°C under low humidity (<20%) until residual moisture is <0.1%. The dried crystals are milled into a fine powder with a controlled particle size distribution, then subjected to rigorous quality control testing—including inductively coupled plasma mass spectrometry (ICP-MS) for trace metal analysis, ion chromatography for anion detection, and moisture analysis—to confirm purity meets ≥99.99% standards. Finally, the product is packaged in ultra-clean, airtight containers (e.g., polyethylene bottles lined with Teflon) in a Class 1000 cleanroom to prevent post-manufacturing contamination.

4. Key Applications in Electronics Industry

Electronic Grade CAN’s ultra-high purity and consistent oxidizing properties make it irreplaceable in critical electronic manufacturing processes, where even minor impurities can lead to device failure.

4.1 Semiconductor Wafer Etching

One of the primary applications of Electronic Grade CAN is in the selective etching of semiconductor wafers (e.g., silicon, gallium arsenide). In acidic solutions, CAN oxidizes the surface layer of the wafer to form a thin oxide film (e.g., SiO₂ on silicon), which is then dissolved by a etchant (e.g., hydrofluoric acid). The precision of this oxidation process—enabled by CAN’s consistent reactivity and low impurities—ensures uniform etching of microstructures (e.g., trenches, vias) with dimensions as small as a few nanometers, a key requirement for advanced microchips (e.g., 7 nm and smaller process nodes). Unlike other oxidizers, CAN does not leave metal residues on the wafer surface, eliminating the need for additional cleaning steps that could damage delicate structures.

4.2 Thin-Film Deposition Precursors

Electronic Grade CAN is used as a precursor for the deposition of ultra-pure cerium oxide (CeO₂) thin films via techniques like chemical vapor deposition (CVD) and atomic layer deposition (ALD). When heated to high temperatures (300–500°C) in a vacuum chamber, CAN decomposes into pure CeO₂, nitrogen oxides, and water vapor—with no residual impurities. These CeO₂ films serve as dielectric layers in dynamic random-access memory (DRAM) devices, barrier layers in copper interconnects (to prevent copper diffusion into silicon), and catalyst supports in fuel cells for portable electronics. The high purity of CAN ensures the CeO₂ films have uniform thickness, low defect density, and excellent electrical properties, critical for device performance.

4.3 Electronic Material Synthesis

In the synthesis of advanced electronic materials, Electronic Grade CAN acts as a oxidizing agent for preparing high-purity ceramics and composites. For example, it is used to oxidize metal organic precursors into ceramic powders (e.g., cerium-zirconium oxides) used in thermal barrier coatings for high-power electronic devices. It also facilitates the synthesis of conductive polymers (e.g., polyaniline) for flexible electronics, where its controlled oxidizing power ensures the polymer has consistent conductivity and mechanical stability. Additionally, CAN is used in the production of quantum dots (e.g., cerium-doped quantum dots) for display technologies, where its purity prevents quenching of the quantum dot’s optical properties.

4.4 Cleaning and Surface Treatment of Electronic Components

Electronic Grade CAN is employed in the cleaning and surface treatment of electronic components, such as printed circuit boards (PCBs) and connectors. It oxidizes organic contaminants (e.g., residual flux, oils) on component surfaces, converting them into soluble byproducts that can be easily rinsed away with ultra-pure water. It also removes thin layers of tarnish (e.g., copper oxide) from metal contacts, improving electrical conductivity and reducing contact resistance. Unlike harsh cleaning agents (e.g., strong acids), CAN operates under mild conditions (room temperature, neutral to acidic pH) and does not corrode delicate components, making it ideal for sensitive electronics.

5. Safety and Handling in Electronic Manufacturing

While Electronic Grade CAN shares similar hazards with other CAN grades, its use in cleanroom environments and electronic manufacturing requires additional safety protocols to protect both workers and the integrity of the product.

Hazards

Electronic Grade CAN poses three primary hazards relevant to electronic manufacturing. First, its oxidizing property: it can accelerate the combustion of flammable materials common in electronics facilities (e.g., organic solvents like acetone, isopropyl alcohol used for cleaning), and large-scale mixing with these solvents may cause exothermic reactions or spontaneous ignition. Second, toxicity: inhalation of its fine powder (common during handling in cleanrooms) can irritate the respiratory tract, and skin contact may cause chemical irritation—though its ultra-purity means it lacks the heavy metal toxins that exacerbate toxicity in lower grades. Third, thermal hazard: decomposition at high temperatures releases toxic NOₓ fumes, which can damage sensitive electronic equipment and pose respiratory risks to workers in confined cleanroom spaces.

Safe Handling Guidelines

Safe handling of Electronic Grade CAN in electronic manufacturing requires adherence to strict protocols, tailored to cleanroom environments. First, personal protective equipment (PPE) must be cleanroom-compatible: this includes nitrile gloves (low-linting, chemical-resistant), safety goggles (anti-fog, compatible with cleanroom suits), a disposable cleanroom lab coat, and a N95 or higher particulate respirator (to prevent inhalation of powder). All PPE must be donned and doffed in designated airlocks to avoid cross-contamination. Second, storage must be in a dedicated cleanroom cabinet—cool (15–25°C), dry (<20% humidity), and away from flammable solvents and reducing agents. The airtight containers must be opened only in a Class 100 laminar flow hood to prevent airborne contamination of the product and the cleanroom. Third, handling: all transfers (e.g., weighing, dissolving) must be done in a laminar flow hood using cleanroom-compatible tools (e.g., Teflon spatulas, quartz beakers) that have been pre-cleaned with ultra-pure water and electronic-grade solvents. Dust generation must be minimized—slow pouring and gentle mixing are recommended—to avoid powder dispersion. Fourth, spill response: in case of a dry spill, the powder must be swept up with a cleanroom-compatible broom and dustpan, then disposed of in a labeled hazardous waste container designated for electronic-grade chemicals. For liquid spills, the solution must be neutralized with electronic-grade sodium bisulfite (to reduce Ce⁴⁺) before cleaning with ultra-pure water, and the area must be tested for residual contamination using ICP-MS to ensure no trace of CAN remains. Fifth, first aid: in case of skin or eye contact, rinse with ultra-pure water for 15 minutes (to avoid introducing impurities to the injury site), and seek medical attention if irritation persists. If inhaled, move the worker to a clean air area and provide oxygen if needed, then consult a medical professional familiar with electronic chemical exposure.

6. Storage and Shelf Life in Electronic Applications

Storage of Electronic Grade CAN is more stringent than other grades, as even minor degradation or contamination can render it unsuitable for electronic use.

Storage Conditions

Optimal storage requires a Class 1000 cleanroom environment with temperature controlled between 15–25°C and relative humidity<20%. The product must be stored in its original airtight, ultra-clean container—opened only in a Class 100 laminar flow hood—to prevent moisture absorption and airborne contamination. It must be kept separate from other chemicals, especially flammable solvents and reducing agents, to avoid accidental reactions. Additionally, the container should be labeled with the manufacturing date, batch number, and expiration date for traceability—a critical requirement in electronics manufacturing, where batch-to-batch consistency is mandatory.

Shelf Life

When stored under ideal cleanroom conditions, Electronic Grade CAN has a shelf life of 1–1.5 years—shorter than reagent grade (2–3 years) due to the higher sensitivity to subtle degradation. Expiration is determined not just by oxidizing activity, but also by impurity levels: over time, even in proper storage, trace impurities may increase slightly (e.g., due to slow leaching from the container), and residual moisture may rise. Before use, expired or near-expired CAN must undergo re-testing—including ICP-MS for impurities, redox titration for oxidizing activity, and moisture analysis—to confirm it still meets electronic-grade standards. If it fails any test, it cannot be used in electronic processes and must be disposed of as hazardous waste in compliance with local regulations for electronic chemicals.

Descriptive:  WNX employs advanced automated production technology and uses high-quality raw materials to produce high-qualityElectronic Grade Cerium Ammonium Nitrate.

Key Features:

High Purity:Electronic Grade Cerium Ammonium Nitrate contains no impurities from rare earth elements (such as iron, calcium, sodium), and the impurity content is low.

Good Solubility:Electronic Grade Cerium Ammonium Nitrate can dissolve rapidly in water and strong acids.

Consistency: The strict batch management in the production of Electronic Grade Cerium Ammonium Nitrate ensures stable quality for industrial large-scale production.

Chemical industry catalysts: Electronic-grade cerium ammonium nitrate, as a powerful single-electron oxidant, is used in organic synthesis to catalyze reactions such as olefin polymerization and the selective oxidation of alcohols to ketones or aldehydes. It is also a key precursor material for preparing cerium-zirconium composite oxides in the production of automotive exhaust purification ternary catalysts.

Pond Phosphorus Remover: Due to its chemical properties, ammonium cerium nitrate can remove phosphates in water by forming a precipitate with phosphate ions, which helps alleviate the problem of eutrophication.

Batteries and energy materials: High-purity ammonium cerium nitrate is an essential raw material for synthesizing cerium-zirconium composite oxides. These materials, as oxygen storage components, are widely used in automotive exhaust three-way catalysts and solid oxide fuel cells (SOFCs), helping to enhance energy conversion efficiency and material stability.

Chemical synthesis intermediates: As a high-purity cerium source, electronic-grade ammonium cerium nitrate is the basic raw material for synthesizing other electronic-grade cerium compounds (such as high-purity cerium oxide). More importantly, it is the core component for preparing chromium etching solutions. These etching solutions are used for precise etching of the chromium metal layer in the manufacturing of liquid crystal displays (LCDs), integrated circuits, and printed circuit boards (PCBs).

1.Neutral labels/packaging (jumbo bag of 1.000kg each net),Two bags per pallet.

2.Vacuum-sealed, then wrapped in air cushion bags, and finally packed into iron drums.

Drum: Steel drums (open-top, 45L capacity, dimensions: φ365mm × 460mm / inner diameter × outer height).

Weight per Drum: 50 kg

Palletization: 18 drums per pallet (total 900 kg/pallet).

Transport Class: Maritime transportation / Air transportatio

Custom packaging available upon request