3818.00.00.20 - Polycrystalline silicon wafers, doped

This HTS classification covers polycrystalline silicon wafers that have been intentionally treated with impurities, a process known as doping. Doping is essential for altering the electrical conductivity of silicon, making it suitable for use in electronic components. These wafers are typically manufactured in disc or similar shapes and are a foundational material for the semiconductor industry.

This specific category is distinguished from its siblings by the material composition. While 3818.00.00.10 covers doped gallium arsenide wafers and 3818.00.00.30 pertains to doped silicon carbide wafers, this classification is exclusively for doped polycrystalline silicon. The "Other" category, 3818.00.00.95, serves as a residual for any other doped chemical elements or compounds in similar forms not otherwise specified.

As this is a leaf node within the HTS database, there are no further subcategories. Therefore, classification into 3818.00.00.20 relies on the precise material (polycrystalline silicon) and its condition (doped) in the specified forms (discs, wafers, or similar). Exclusions would generally be undoped silicon wafers or silicon in other forms not suitable for electronic applications.