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: > Other semiconductor devices: > Other > 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 8541.59.00.40
Silicon Carbide Power MOSFET Wafer
A 6-inch silicon carbide (SiC) wafer containing unmounted chips designed for high-voltage power MOSFET transistors used in electric vehicles and renewable energy inverters. Classified under HTS 8541.59.00.40 as unmounted semiconductor wafers for power semiconductor devices. These wafers undergo dicing into individual dice post-import for die attach in power modules.
Gallium Nitride RF Transistor Die
Unmounted GaN high-electron-mobility transistor (HEMT) dice on 4-inch wafers for 5G base stations and radar systems, featuring 50V breakdown voltage. Falls under HTS 8541.59.00.40 as unmounted semiconductor dice for RF power amplification devices. Imported for die bonding onto RF modules.
8-Inch Silicon CMOS Sensor Wafer
300mm silicon wafer with unseparated CMOS image sensor chips for industrial machine vision cameras, featuring 12MP resolution per die. HTS 8541.59.00.40 applies to photosensitive semiconductor wafers not yet diced. Used in automation and surveillance equipment.
IGBT Silicon Die on Wafer
200mm silicon wafer containing unmounted insulated-gate bipolar transistor (IGBT) chips rated 1200V/200A for industrial motor drives and UPS systems. Classified as unmounted semiconductor dice under HTS 8541.59.00.40. Post-import processing includes wire bonding and encapsulation.
Schottky Barrier Diode Wafer
150mm silicon wafer with unmounted Schottky diode chips for high-frequency power rectification in switch-mode power supplies, 600V/10A rating. HTS 8541.59.00.40 covers these unseparated semiconductor wafers. Low forward voltage drop enables efficient DC-DC conversion.
SiC MOSFET Test Wafer
4-inch silicon carbide test wafer with process control monitor (PCM) structures and unmounted MOSFET dice for automotive traction inverters. Classified under HTS 8541.59.00.40 as semiconductor device wafers. Used for yield monitoring and process qualification.
GaAs HBT MMIC Wafer
100mm gallium arsenide wafer with heterojunction bipolar transistor monolithic microwave integrated circuit chips for satellite communications, operating 2-18 GHz. HTS 8541.59.00.40 for unmounted semiconductor wafers containing MMIC devices. High linearity for L-band transponders.
MEMS Pressure Sensor Wafer
200mm silicon wafer with unmounted micro-electro-mechanical systems (MEMS) capacitive pressure sensor dice for automotive tire pressure monitoring systems (TPMS). HTS 8541.59.00.40 applies to semiconductor-based transducer wafers. Each die measures 0-50 psi with integrated signal conditioning.
VCSEL Array Wafer
6-inch GaAs wafer containing vertical-cavity surface-emitting laser diode arrays with 940nm wavelength for 3D facial recognition in smartphones. Classified under HTS 8541.59.00.40 as unmounted light-emitting diode (LED) wafers. 8x8 emitter arrays per die.
Power SiC Diode Wafer
150mm SiC wafer with merged p-n Schottky diode chips rated 1700V/50A for photovoltaic inverters and traction systems. HTS 8541.59.00.40 for unmounted power semiconductor wafers. Ultra-low reverse recovery enables high switching frequencies.