Unmounted chips, dice and wafers
Semiconductor devices (for example, diodes, transistors, semiconductor-based transducers); photosensitive semiconductor devices, including photovoltaic cells whether or not assembled in modules or made up into panels; light-emitting diodes (LED), whether or not assembled with other light-emitting diodes (LED); mounted piezo-electric crystals; parts thereof: > Thyristors, diacs and triacs, other than photosensitive devices > Unmounted chips, dice and wafers
Duty Rate (from China)
Effective with respect to entries on or after January 1, 2025, articles the product of China, as provided for in subdivision (f) of U.S. note 31 to this subchapter
Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Products classified under HTS 8541.30.00.40
Silicon Carbide Thyristor Wafer
Unmounted silicon carbide wafers designed for fabricating high-power thyristors used in industrial motor controls and power grids. These wafers meet the subheading criteria for thyristor chips under 8541.30.00.40 as they are unmounted semiconductor dice in wafer form prior to dicing. They enable high-voltage switching applications due to their superior thermal management.
Gallium Nitride Diac Wafer
Unmounted GaN wafers for diac production, used in high-frequency switching circuits and surge protection devices. Classified under 8541.30.00.40 as unmounted semiconductor wafers specifically for diac devices which are bidirectional trigger thyristors. Their wide bandgap properties enable efficient operation in power electronics.
1200V Silicon Triac Die
Unmounted silicon dice rated at 1200V for triac fabrication, essential for AC motor controls and lighting dimmers. These individual semiconductor chips qualify under 8541.30.00.40 as unmounted triac dice before packaging. Triacs provide bidirectional switching for household appliances.
High-Power Thyristor Wafer (4-inch)
4-inch unmounted silicon wafers for manufacturing high-power thyristors used in HVDC transmission systems. Specifically classified under 8541.30.00.40 due to thyristor-specific epitaxial layers and doping. These enable megawatt-scale power control applications.
SiC Triac Chip (Unmounted)
Individual unmounted silicon carbide chips for triac devices operating at 600V-1200V in EV power electronics. Falls under 8541.30.00.40 as unmounted triac semiconductor dice with bidirectional gate control structure. Superior to silicon in high-temperature performance.
Industrial Diac Wafer (6-inch)
6-inch silicon wafers engineered for diac production in industrial dimming and timing circuits. Classified specifically under 8541.30.00.40 for unmounted diac wafers with symmetrical breakover voltage characteristics. Supports precise AC phase control applications.
800A Thyristor Dice Sheet
Pre-diced sheet of 800A-rated thyristor dice on tape for high-current traction applications. Each unmounted die qualifies under 8541.30.00.40 as thyristor semiconductor chips. Used in railway and marine propulsion systems.
Fast-Recovery Triac Wafer
Unmounted wafers optimized for fast turn-off triacs used in SMPS and inverters. Specifically under 8541.30.00.40 due to triac gate structure and recovery time specs <1μs. Enables high-frequency AC switching.
Phase-Control Thyristor Chip
Unmounted 16A phase-control thyristor chips for lighting and heating applications. Classified under 8541.30.00.40 as discrete thyristor dice with integral phase angle control. Common in TRIAC-alternative single-quadrant applications.
High-Temperature Diac Die
Unmounted diac dice rated for 175°C operation in automotive ignition systems. Falls under 8541.30.00.40 as semiconductor wafers for diac devices with high-temperature junction specs. Critical for engine timing circuits.