Copper Alloy RF Window for Wafer Polisher Vacuum Chamber from China

Vacuum-tight copper alloy RF window for microwave coupling in wafer polishers and lappers (heading 8426). Enables plasma-assisted polishing for flat semiconductor wafer surfaces. 8431.49.90.92 for copper parts of semiconductor processing equipment.

Duty Rate — China → United States

35%

Rate breakdown

9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0125%Except as provided in headings 9903.88.05, 9903.88.06, 9903.88.07, 9903.88.08, 9903.88.10, 9903.88.11, 9903.88.14, 9903.88.19, 9903.88.50, 9903.88.52, 9903.88.58, 9903.88.60, 9903.88.62, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(a) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(b) [to this subchapter]

Import Tips

RF transmission specs and vacuum rating docs confirm semiconductor-specific design

Label as 'not for general lab use' to prevent 8419 reclassification